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1.
J Biophotonics ; : e202300491, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664987

RESUMEN

As a rapidly growing field, biophotonics demonstrates an increasingly higher demand for interdisciplinary professionals and requires the implementation of a structured approach to educational and outreach activities focused on appropriate curriculum, and teaching and learning for audiences with diverse technical backgrounds and learning styles. Our study shows the main findings upon applying this approach to biophotonics workshops delivered 2 consecutive years while updating and improving learning outcomes, teaching strategies, workshop content based on student and teacher feedback. We provided resources for a variety of lecture-based, experimental, computer simulation activities. Quality of subject matter, teaching, and overall learning was rated as "Very good" or "Good" by 88%, 76%, and 82% of students in average, respectively. Application of our teaching strategies and materials during short- and long-term workshops/courses could potentially increase the interest in pursuing careers in the biophotonics field and related areas, leading to standardized approaches in designing education and outreach events across centers.

3.
FASEB J ; 38(1): e23358, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38050671

RESUMEN

MicroRNA (miRNA)-mediated mRNA regulation directs many homeostatic and pathological processes, but how miRNAs coordinate aberrant esophageal inflammation during eosinophilic esophagitis (EoE) is poorly understood. Here, we report a deregulatory axis where microRNA-155 (miR-155) regulates epithelial barrier dysfunction by selectively constraining tight junction CLDN7 (claudin-7). MiR-155 is elevated in the esophageal epithelium of biopsies from patients with active EoE and in cell culture models. MiR-155 localization using in situ hybridization (ISH) in patient biopsies and intra-epithelial compartmentalization of miR-155 show expression predominantly within the basal epithelia. Epithelial miR-155 activity was evident through diminished target gene expression in 3D organotypic cultures, particularly in relatively undifferentiated basal cell states. Mechanistically, generation of a novel cell line with enhanced epithelial miR-155 stable overexpression induced a functionally deficient epithelial barrier in 3D air-liquid interface epithelial cultures measured by transepithelial electrical resistance (TEER). Histological assessment of 3D esophageal organoid cultures overexpressing miR-155 showed notable dilated intra-epithelial spaces. Unbiased RNA-sequencing analysis and immunofluorescence determined a defect in epithelial barrier tight junctions and revealed a selective reduction in the expression of critical esophageal tight junction molecule, claudin-7. Together, our data reveal a previously unappreciated role for miR-155 in mediating epithelial barrier dysfunction in esophageal inflammation.


Asunto(s)
Claudinas , Esofagitis Eosinofílica , MicroARNs , Humanos , Claudinas/genética , Esofagitis Eosinofílica/genética , Esofagitis Eosinofílica/metabolismo , Esofagitis Eosinofílica/patología , Células Epiteliales/metabolismo , Hipoxia/metabolismo , Inflamación/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Uniones Estrechas/metabolismo
4.
Sci Adv ; 9(45): eadi1428, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37948525

RESUMEN

The direct manipulation of spins via light may provide a path toward ultrafast energy-efficient devices. However, distinguishing the microscopic processes that can occur during ultrafast laser excitation in magnetic alloys is challenging. Here, we study the Heusler compound Co2MnGa, a material that exhibits very strong light-induced spin transfers across the entire M-edge. By combining the element specificity of extreme ultraviolet high-harmonic probes with time-dependent density functional theory, we disentangle the competition between three ultrafast light-induced processes that occur in Co2MnGa: same-site Co-Co spin transfer, intersite Co-Mn spin transfer, and ultrafast spin flips mediated by spin-orbit coupling. By measuring the dynamic magnetic asymmetry across the entire M-edges of the two magnetic sublattices involved, we uncover the relative dominance of these processes at different probe energy regions and times during the laser pulse. Our combined approach enables a comprehensive microscopic interpretation of laser-induced magnetization dynamics on time scales shorter than 100 femtoseconds.

6.
World J Gastrointest Endosc ; 15(5): 368-375, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37274556

RESUMEN

Rectal neuroendocrine tumours represent a rare colorectal tumour with a 10 fold increased prevalence due to incidental detection in the era of colorectal screening. Patient outcomes with early diagnosis are excellent. However endoscopic recognition of this lesion is variable and misdiagnosis can result in suboptimal endoscopic resection with subsequent uncertainty in relation to optimal long-term management. Endoscopic techniques have shown particular utility in managing this under-recognized neuroendocrine tumour.

7.
Mar Drugs ; 21(6)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37367662

RESUMEN

The effects of the consumption of an extract of the brown seaweed Ascophyllum nodosum (BSW) on postprandial glucose and insulin responses to white bread were investigated in an acute, randomized, double-blind, three-arm, crossover, controlled trial in healthy, normoglycemic subjects. Sixteen subjects were administered either control white bread (50 g total digestible carbohydrates) or white bread with 500 mg or 1000 mg of BSW extract. Biochemical parameters were measured in venous blood over 3 h. Significant inter-individual variation in the glycaemic response to white bread was observed. Analysis of the responses of all subjects to either 500 mg or 1000 mg of BSW extract versus control revealed no significant effects of treatments. The variation in response to the control was used to classify individuals into glycaemic responders and non-responders. In the sub-cohort of 10 subjects with peak glucose levels after white bread above 1 mmol/L, we observed a significant decrease in maximum levels of plasma glucose after the intervention meal with 1000 mg of extract compared with the control. No adverse effects were reported. Further work is warranted to define all factors that determine "responders" to the effects of brown seaweed extracts and identify the cohort that would benefit the most from their consumption.


Asunto(s)
Algas Marinas , Humanos , Glucemia , Voluntarios Sanos , Control Glucémico , Glucosa , Insulina , Carbohidratos de la Dieta , Verduras , Método Doble Ciego
8.
Molecules ; 28(7)2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-37049704

RESUMEN

Selenium methionine (SeMet) is an essential micronutrient required for normal body function and is associated with additional health benefits. However, oral administration of SeMet can be challenging due to its purported narrow therapeutic index, low oral bioavailability, and high susceptibility to oxidation. To address these issues, SeMet was entrapped in zein-coated nanoparticles made from chitosan using an ionic gelation formulation. The high stability of both the SeMet and selenomethionine nanoparticles (SeMet-NPs) was established using cultured human intestinal and liver epithelial cells, rat liver homogenates, and rat intestinal homogenates and lumen washes. Minimal cytotoxicity to Caco-2 and HepG2 cells was observed for SeMet and SeMet-NPs. Antioxidant properties of SeMet were revealed using a Reactive Oxygen Species (ROS) assay, based on the observation of a concentration-dependent reduction in the build-up of peroxides, hydroxides and hydroxyl radicals in Caco-2 cells exposed to SeMet (6.25-100 µM). The basal apparent permeability coefficient (Papp) of SeMet across isolated rat jejunal mucosae mounted in Ussing chambers was low, but the Papp was increased when presented in NP. SeMet had minimal effects on the electrogenic ion secretion of rat jejunal and colonic mucosae in Ussing chambers. Intra-jejunal injections of SeMet-NPs to rats yielded increased plasma levels of SeMet after 3 h for the SeMet-NPs compared to free SeMet. Overall, there is potential to further develop SeMet-NPs for oral supplementation due to the increased intestinal permeability, versus free SeMet, and the low potential for toxicity.


Asunto(s)
Nanopartículas , Selenio , Ratas , Humanos , Animales , Selenometionina/farmacología , Células CACO-2 , Antioxidantes/farmacología , Suplementos Dietéticos
9.
Rev Sci Instrum ; 94(3): 033001, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37012828

RESUMEN

High harmonic generation (HHG) makes it possible to measure spin and charge dynamics in materials on femtosecond to attosecond timescales. However, the extreme nonlinear nature of the high harmonic process means that intensity fluctuations can limit measurement sensitivity. Here we present a noise-canceled, tabletop high harmonic beamline for time-resolved reflection mode spectroscopy of magnetic materials. We use a reference spectrometer to independently normalize the intensity fluctuations of each harmonic order and eliminate long term drift, allowing us to make spectroscopic measurements near the shot noise limit. These improvements allow us to significantly reduce the integration time required for high signal-to-noise (SNR) measurements of element-specific spin dynamics. Looking forward, improvements in the HHG flux, optical coatings, and grating design can further reduce the acquisition time for high SNR measurements by 1-2 orders of magnitude, enabling dramatically improved sensitivity to spin, charge, and phonon dynamics in magnetic materials.

10.
Nat Nanotechnol ; 18(3): 227-232, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36690739

RESUMEN

Topological magnetic monopoles (TMMs), also known as hedgehogs or Bloch points, are three-dimensional (3D) non-local spin textures that are robust to thermal and quantum fluctuations due to the topology protection1-4. Although TMMs have been observed in skyrmion lattices1,5, spinor Bose-Einstein condensates6,7, chiral magnets8, vortex rings2,9 and vortex cores10, it has been difficult to directly measure the 3D magnetization vector field of TMMs and probe their interactions at the nanoscale. Here we report the creation of 138 stable TMMs at the specific sites of a ferromagnetic meta-lattice at room temperature. We further develop soft X-ray vector ptycho-tomography to determine the magnetization vector and emergent magnetic field of the TMMs with a 3D spatial resolution of 10 nm. This spatial resolution is comparable to the magnetic exchange length of transition metals11, enabling us to probe monopole-monopole interactions. We find that the TMM and anti-TMM pairs are separated by 18.3 ± 1.6 nm, while the TMM and TMM, and anti-TMM and anti-TMM pairs are stabilized at comparatively longer distances of 36.1 ± 2.4 nm and 43.1 ± 2.0 nm, respectively. We also observe virtual TMMs created by magnetic voids in the meta-lattice. This work demonstrates that ferromagnetic meta-lattices could be used as a platform to create and investigate the interactions and dynamics of TMMs. Furthermore, we expect that soft X-ray vector ptycho-tomography can be broadly applied to quantitatively image 3D vector fields in magnetic and anisotropic materials at the nanoscale.

11.
Sci Rep ; 12(1): 19734, 2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36396677

RESUMEN

Methods to probe and understand the dynamic response of materials following impulsive excitation are important for many fields, from materials and energy sciences to chemical and neuroscience. To design more efficient nano, energy, and quantum devices, new methods are needed to uncover the dominant excitations and reaction pathways. In this work, we implement a newly-developed superlet transform-a super-resolution time-frequency analytical method-to analyze and extract phonon dynamics in a laser-excited two-dimensional (2D) quantum material. This quasi-2D system, 1T-TaSe2, supports both equilibrium and metastable light-induced charge density wave (CDW) phases mediated by strongly coupled phonons. We compare the effectiveness of the superlet transform to standard time-frequency techniques. We find that the superlet transform is superior in both time and frequency resolution, and use it to observe and validate novel physics. In particular, we show fluence-dependent changes in the coupled dynamics of three phonon modes that are similar in frequency, including the CDW amplitude mode, that clearly demonstrate a change in the dominant charge-phonon couplings. More interestingly, the frequencies of the three phonon modes, including the strongly-coupled CDW amplitude mode, remain time- and fluence-independent, which is unusual compared to previously investigated materials. Our study opens a new avenue for capturing the coherent evolution and couplings of strongly-coupled materials and quantum systems.

12.
Int J Mol Sci ; 23(19)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36232463

RESUMEN

Isoleucine-Proline-Proline (IPP) and Leucine-Lysine-Proline (LKP) are food-derived tripeptides whose antihypertensive functions have been demonstrated in hypertensive rat models. However, peptides display low oral bioavailability due to poor intestinal epithelial permeability and instability. IPP and LKP were formulated into nanoparticles (NP) using chitosan (CL113) via ionotropic gelation and then coated with zein. Following addition of zein, a high encapsulation efficiency (EE) (>80%) was obtained for the NP. In simulated gastric fluid (SGF), 20% cumulative release of the peptides was achieved after 2 h, whereas in simulated intestinal fluid (SIF), ~90% cumulative release was observed after 6 h. Higher colloidal stability (39−41 mV) was observed for the coated NP compared to uncoated ones (30−35 mV). In vitro cytotoxicity studies showed no reduction in cellular viability of human intestinal epithelial Caco-2 and HepG2 liver cells upon exposure to NP and NP components. Administration of NP encapsulating IPP and LKP by oral gavage to spontaneously hypertensive rats (SHR) attenuated systolic blood pressure (SBP) for 8 h. This suggests that the NP provide appropriate release to achieve prolonged hypotensive effects in vivo. In conclusion, chitosan-zein nanoparticles (CZ NP) have potential as oral delivery system for the encapsulation of IPP and LKP.


Asunto(s)
Quitosano , Nanopartículas , Zeína , Administración Oral , Animales , Antihipertensivos/farmacología , Células CACO-2 , Portadores de Fármacos , Humanos , Leucina , Lisina , Oligopéptidos , Tamaño de la Partícula , Péptidos , Prolina , Ratas , Ratas Endogámicas SHR
13.
Pain Ther ; 11(2): 701-712, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35471625

RESUMEN

INTRODUCTION: As 5-HT1B receptor agonists, triptans produce vasoconstriction and have cardiovascular contraindications and precautions. Lasmiditan, a selective 5-HT1F receptor agonist, has a low affinity for 5-HT1B receptors, does not cause vasoconstriction, and is free of cardiovascular contraindications and precautions. The objective of this post hoc analysis was to evaluate the efficacy and safety of lasmiditan in patients with and without at least one triptan contraindication. METHODS: Patient subgroups, with and without triptan contraindications, were analyzed from pooled patient data from four randomized, double-blind, placebo-controlled clinical trials (SAMURAI, SPARTAN, CENTURION, and MONONOFU). Patients experiencing a single migraine attack of moderate or severe intensity were treated with lasmiditan 50 mg (SPARTAN and MONONOFU only), 100 mg, 200 mg, or placebo, and efficacy data were recorded in an electronic diary. RESULTS: Of 5704 patients, 207 (3.6%) patients had at least one contraindication to triptans. Overall subgroup analysis revealed that the effects of lasmiditan on pain freedom, pain relief, freedom from most bothersome symptom, disability freedom, and Patient Global Impression of Change at 2 h post-dose did not differ in patient groups with and without triptan contraindications. These outcomes generally showed a similar benefit pattern for lasmiditan in both subgroups, with all results being statistically significant in patients without contraindications, and pain relief being statistically significant in patients with contraindications. The safety and tolerability profiles of patients with triptan versus without triptan contraindications were similar, including dizziness in 18.3 to 22.8% and somnolence in 7.9 to 9.9% of patients at the highest dose of lasmiditan. CONCLUSIONS: In pooled analyses from four trials, patients with and without triptan contraindications did not differ in their patterns of lasmiditan efficacy. Lasmiditan may be a treatment option in patients with contraindications to triptans. TRIAL REGISTRATION NUMBERS: SAMURAI, NCT:02439320; SPARTAN, NCT:02605174; CENTURION, NCT:03670810; and MONONOFU, NCT:03962738.

14.
Res Social Adm Pharm ; 18(3): 2392-2402, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33903064

RESUMEN

BACKGROUND: Older adults with cancer often require multiple medications (polypharmacy) comprising cancer-specific treatments, supportive care medications (e.g. analgesics), and medications for pre-existing health conditions. Increasing numbers of medications may increase risks of potentially inappropriate prescribing and non-adherence. OBJECTIVE: To provide an overview of evaluations of interventions aimed at optimising medication prescribing and/or adherence in older adults with cancer. METHODS: A systematic scoping review was undertaken. Four databases (PubMed, EMBASE, CINAHL, PsycINFO) were searched using relevant search terms (e.g. cancer, older adults). Eligible studies evaluated interventions seeking to improve medication prescribing and/or adherence in older adults (≥65 years) with cancer using a comparative evaluation. All outcomes for studies that met inclusion criteria were included in the review. Extracted data were collated using tables and accompanying narrative descriptive summaries. The review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. RESULTS: Nine studies met inclusion criteria comprising five randomised controlled trials (RCTs) and four before-and-after study designs. Studies were primarily conducted in oncology clinics, ranging from single study sites to 109 oncology clinics. Sample sizes ranged between 33 and 4844 patients. Interventions most commonly involved patient education (n = 6) delivered by pharmacists or nurses. Three studies reported on prescribing-related outcomes and seven studies reported on adherence-related outcomes, using different terminology and assessment methods. Prescribing-related outcomes focused on medication appropriateness (using Beers criteria) and drug-related problems including drug interactions. Adherence-related outcomes included assessments of self-reported medication adherence and calculation of patients' medication possession ratio. CONCLUSIONS: This scoping review highlights a lack of robust evaluations of interventions aimed at optimising medication prescribing and adherence in older adults with cancer. Future research should improve rigour during intervention development, evaluation and reporting in order to generate findings that could inform future practice.


Asunto(s)
Prescripciones de Medicamentos , Neoplasias , Anciano , Humanos , Prescripción Inadecuada/prevención & control , Cumplimiento de la Medicación , Neoplasias/tratamiento farmacológico , Polifarmacia , Lista de Medicamentos Potencialmente Inapropiados
15.
Int J Mol Sci ; 22(9)2021 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-34065111

RESUMEN

Dysregulated protease activity has long been implicated in the pathogenesis of chronic lung diseases and especially in conditions that display mucus obstruction, such as chronic obstructive pulmonary disease, cystic fibrosis, and non-cystic fibrosis bronchiectasis. However, our appreciation of the roles of proteases in various aspects of such diseases continues to grow. Patients with muco-obstructive lung disease experience progressive spirals of inflammation, mucostasis, airway infection and lung function decline. Some therapies exist for the treatment of these symptoms, but they are unable to halt disease progression and patients may benefit from novel adjunct therapies. In this review, we highlight how proteases act as multifunctional enzymes that are vital for normal airway homeostasis but, when their activity becomes immoderate, also directly contribute to airway dysfunction, and impair the processes that could resolve disease. We focus on how proteases regulate the state of mucus at the airway surface, impair mucociliary clearance and ultimately, promote mucostasis. We discuss how, in parallel, proteases are able to promote an inflammatory environment in the airways by mediating proinflammatory signalling, compromising host defence mechanisms and perpetuating their own proteolytic activity causing structural lung damage. Finally, we discuss some possible reasons for the clinical inefficacy of protease inhibitors to date and propose that, especially in a combination therapy approach, proteases represent attractive therapeutic targets for muco-obstructive lung diseases.


Asunto(s)
Inmunidad Mucosa , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/metabolismo , Moco/metabolismo , Péptido Hidrolasas/metabolismo , Animales , Enfermedad Crónica , Cilios/inmunología , Cilios/metabolismo , Susceptibilidad a Enfermedades , Humanos , Transporte Iónico , Enfermedades Pulmonares/diagnóstico , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Transducción de Señal
16.
J Nutr Sci ; 10: e5, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33889388

RESUMEN

Type II diabetes is considered the most common metabolic disorder in the developed world and currently affects about one in ten globally. A therapeutic target for the management of type II diabetes is the inhibition of α- glucosidase, an essential enzyme located at the brush border of the small intestinal epithelium. The inhibition of α-glucosidase results in reduced digestion of carbohydrates and a decrease in postprandial blood glucose. Although pharmaceutical synthetic inhibitors are available, these are usually associated with significant gastrointestinal side effects. In the present study, the impact of inhibitors derived from edible brown algae is being investigated and compared for their effect on glycaemic control. Carbohydrate- and polyphenolic-enriched extracts derived from Ascophyllum nodosum, Fucus vesiculosus and Undaria pinnatifida were characterised and screened for their inhibitory effects on maltase and sucrase enzymes. Furthermore, enzyme kinetics and the mechanism of inhibition of maltase and sucrase were determined using linear and nonlinear regression methods. All tested extracts showed a dose-dependent inhibitory effect of α-glucosidase with IC50 values ranging from 0⋅26 to 0⋅47 mg/ml for maltase; however, the only extract that was able to inhibit sucrase activity was A. nodosum, with an IC50 value of 0⋅83 mg/ml. The present study demonstrates the mechanisms in which different brown seaweed extracts with varying composition and molecular weight distribution differentially inhibit α-glucosidase activities. The data highlight that all brown seaweed extracts are not equal in the inhibition of carbohydrate digestive enzymes involved in postprandial glycaemia.


Asunto(s)
Glucemia , Phaeophyceae , Extractos Vegetales , Algas Marinas , Metabolismo de los Hidratos de Carbono , Diabetes Mellitus Tipo 2 , Dieta , Inhibidores de Glicósido Hidrolasas/farmacología , Humanos , Extractos Vegetales/farmacología , Sacarasa/antagonistas & inhibidores , alfa-Glucosidasas
17.
Front Med (Lausanne) ; 7: 589553, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33195353

RESUMEN

Acute respiratory distress syndrome (ARDS) is associated with increased morbidity and mortality in the elderly population (≥65 years of age). Additionally, age is widely reported as a risk factor for the development of ARDS. However, the underlying pathophysiological mechanisms behind the increased risk of developing, and increased severity of, ARDS in the elderly population are not fully understood. This is compounded by the significant heterogeneity observed in patients with ARDS. With an aging population worldwide, a better understanding of these mechanisms could facilitate the development of therapies to improve outcomes in this population. In this review, the current clinical evidence of age as a risk factor and prognostic indicator in ARDS and the potential underlying mechanisms that may contribute to these factors are outlined. In addition, research on age-dependent treatment options and biomarkers, as well as future prospects for targeting these underlying mechanisms, are discussed.

18.
Front Immunol ; 11: 2182, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32983184

RESUMEN

Helminths (worms) are one of the most successful organisms in nature given their ability to infect millions of humans and animals worldwide. Their success can be attributed to their ability to modulate the host immune response for their own benefit by releasing excretory-secretory (ES) products. Accordingly, ES products have been lauded as a potential source of immunomodulators/biotherapeutics for an array of inflammatory diseases. However, there is a significant lack of knowledge regarding the specific interactions between these products and cells of the immune response. Many different compounds have been identified within the helminth "secretome," including antioxidants, proteases, mucin-like peptides, as well as helminth defense molecules (HDMs), each with unique influences on the host inflammatory response. HDMs are a conserved group of proteins initially discovered in the secretome of the liver fluke, Fasciola hepatica. HDMs interact with cell membranes without cytotoxic effects and do not exert antimicrobial activity, suggesting that these peptides evolved specifically for immunomodulatory purposes. A peptide generated from the HDM sequence, termed FhHDM-1, has shown extensive anti-inflammatory abilities in clinically relevant models of diseases such as diabetes, multiple sclerosis, asthma, and acute lung injury, offering hope for the development of a new class of therapeutics. In this review, the current knowledge of host immunomodulation by a range of F. hepatica ES products, particularly FhHDM-1, will be discussed. Immune regulators, including HDMs, have been identified from other helminths and will also be outlined to broaden our understanding of the variety of effects these potent molecules exert on immune cells.


Asunto(s)
Fasciola hepatica/inmunología , Fascioliasis/inmunología , Proteínas del Helminto/inmunología , Interacciones Huésped-Patógeno/inmunología , Evasión Inmune/inmunología , Animales , Antígenos Helmínticos/inmunología , Secuencia Conservada , Fascioliasis/veterinaria , Humanos , Inmunidad , Inmunomodulación , Ratones , Proteínas Citotóxicas Formadoras de Poros/inmunología , Especificidad de la Especie
19.
Sci Total Environ ; 690: 1-6, 2019 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-31299565

RESUMEN

The rapid dissemination of carbapenemase-producing Enterobacterales (CPE) is a major public health concern. The role that the aquatic environment plays in this dissemination is underexplored. This study aimed to examine seawater as a reservoir for CPE. Seawater sampling took place at a bathing site throughout the 2017 bathing season. Each 30 L sample (n = 6) was filtered using the CapE filtration system. Wastewater samples (200 mL) (pre-treatment (n = 3) and post-treatment (n = 3)) were obtained from a nearby secondary wastewater treatment plant, during the same time period. All samples were examined for CPE. Whole genome sequencing of confirmed CPE was carried out using Illumina sequencing. Isolate genomes were hosted in corresponding BIGSdb databases and analyses were performed using multiple web-based tools. CPE was detected in 2/6 seawater samples. It was not detected in any wastewater samples. OXA-48-like-producing ST131 Escherichia coli (Ec_BM707) was isolated from a seawater sample collected in May 2017 and OXA-48-like-producing ST101 Klebsiella pneumoniae (Kp_BM758) was isolated from a seawater sample collected in August 2017. The genomes of the environmental isolates were compared to a collection of previously described Irish clinical OXA-48-like-producing Enterobacterales (n = 105). Ec_BM707 and Kp_BM758 harboured blaOXA-48 on similar mobile genetic elements to those identified in the clinical collection (pOXA-48 fragment in Ec_BM707 and IncL(pOXA-48) plasmid in Kp_BM758). Genetic similarities were observed between Ec_BM707 and several of the clinical ST131 E. coli, with allele matches at up to 98.2% of 2513 core genome multilocus sequence type (cgMLST) loci. In contrast, Kp_BM758 and the 34 clinical K. pneumoniae were genetically distant. The source of the CPE at this site was not identified. The detection of OXA-48-like-producing ST131 E. coli and OXA-48-like-producing ST101 K. pneumoniae in Irish recreational water is a concern. The potential for contamination of the aquatic environment to contribute to dissemination of CPE in Europe warrants further study.


Asunto(s)
Enterobacteriaceae/fisiología , Microbiología del Agua , Enterobacteriaceae/aislamiento & purificación , Monitoreo del Ambiente , Recreación , beta-Lactamasas/metabolismo
20.
Food Res Int ; 120: 295-304, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31000242

RESUMEN

Selenoamino acids (SeAAs) have been shown to possess antioxidant and anticancer properties. However, their bioaccessibility is low and they may be toxic above the recommended nutritional intake level, thus improved targeted oral delivery methods are desirable. In this work, the SeAAs, Methylselenocysteine (MSC) and selenocystine (SeCys2) were encapsulated into nanoparticles (NPs) using the mucoadhesive polymer chitosan (Cs), via ionotropic gelation with tripolyphosphate (TPP) and the NPs produced were then coated with zein (a maize derived prolamine rich protein). NPs with optimized physicochemical properties for oral delivery were obtained at a 6: 1 ratio of Cs:TPP, with a 1:0.75 mass ratio of Cs:zein coating (diameter ~260 nm, polydispersivity index ~0.2, zeta potential >30 mV). Scanning Electron Microscopy (SEM) analysis showed that spheroidal, well distributed particles were obtained. Encapsulation Efficiencies of 80.7% and 78.9% were achieved, respectively, for MSC and SeCys2 loaded NPs. Cytotoxicity studies of MSC loaded NPs showed no decrease in cellular viability in either Caco-2 (intestine) or HepG2 (liver) cells after 4 and 72 h exposures. For SeCys2 loaded NPs, although no cytotoxicity was observed in Caco-2 cells after 4 h, a significant reduction in cytotoxicity was observed, compared to pure SeCys2, across all test concentrations in HepG2 after 72 h exposure. Accelerated thermal stability testing of both loaded NPs indicated good stability under normal storage conditions. Lastly, after 6 h exposure to simulated gastrointestinal tract environments, the sustained release profile of the formulation showed that 62 ±â€¯8% and 69 ±â€¯4% of MSC and SeCys2, had been released from the NPs respectively.


Asunto(s)
Anticarcinógenos/análisis , Antivirales/análisis , Cistina/análisis , Suplementos Dietéticos , Compuestos de Organoselenio/análisis , Selenocisteína/análisis , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Cistina/análogos & derivados , Geles/química , Células Hep G2 , Humanos , Microscopía Electrónica de Rastreo , Nanopartículas/química , Tamaño de la Partícula , Polifosfatos/análisis , Selenocisteína/análogos & derivados , Zeína/química
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