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BACKGROUND: The purinergic P2X7 receptor (P2X7R) plays an important role in the crosstalk between pancreatic stellate cells (PSCs) and cancer cells, thus promoting progression of pancreatic ductal adenocarcinoma (PDAC). Single nucleotide polymorphisms (SNPs) in the P2X7R have been reported for several cancers, but have not been explored in PDAC. MATERIALS AND METHODS: Blood samples from PDAC patients and controls were genotyped for 11 non-synonymous SNPs in P2X7R and a risk analysis was performed. Relevant P2X7R-SNP GFP variants were expressed in PSCs and cancer cells and their function was assayed in the following tests. Responses in Ca2+ were studied with Fura-2 and dye uptake with YO-PRO-1. Cell migration was monitored by fluorescence microscopy. Released cytokines were measured with MSD assay. RESULTS: Risk analysis showed that two SNPs 474G>A and 853G>A (rs28360447, rs7958316), that lead to the Gly150Arg and Arg276His variants, had a significant but opposite risk association with PDAC development, protecting against and predisposing to the disease, respectively. In vitro experiments performed on cancer cells and PSCs expressing the Gly150Arg variant showed reduced intracellular Ca2+ response, fluorescent dye uptake, and cell migration, while the Arg276His variant reduced dye uptake but displayed WT-like Ca2+ responses. As predicted, P2X7R was involved in cytokine release (IL-6, IL-1ß, IL-8, TNF-α), but the P2X7R inhibitors displayed varied effects. CONCLUSION: In conclusion, we provide evidence for the P2X7R SNPs association with PDAC and propose that they could be considered as potential biomarkers.
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BACKGROUND: Acute or new-onset atrial fibrillation (NOAF) is the most common cardiac arrhythmia in critically ill adult patients, and observational data suggests that NOAF is associated to adverse outcomes. METHODS: We prepared this guideline according to the Grading of Recommendations Assessment, Development and Evaluation methodology. We posed the following clinical questions: (1) what is the better first-line pharmacological agent for the treatment of NOAF in critically ill adult patients?, (2) should we use direct current (DC) cardioversion in critically ill adult patients with NOAF and hemodynamic instability caused by atrial fibrillation?, (3) should we use anticoagulant therapy in critically ill adult patients with NOAF?, and (4) should critically ill adult patients with NOAF receive follow-up after discharge from hospital? We assessed patient-important outcomes, including mortality, thromboembolic events, and adverse events. Patients and relatives were part of the guideline panel. RESULTS: The quantity and quality of evidence on the management of NOAF in critically ill adults was very limited, and we did not identify any relevant direct or indirect evidence from randomized clinical trials for the prespecified PICO questions. We were able to propose one weak recommendation against routine use of therapeutic dose anticoagulant therapy, and one best practice statement for routine follow-up by a cardiologist after hospital discharge. We were not able to propose any recommendations on the better first-line pharmacological agent or whether to use DC cardioversion in critically ill patients with hemodynamic instability induced by NOAF. An electronic version of this guideline in layered and interactive format is available in MAGIC: https://app.magicapp.org/#/guideline/7197. CONCLUSIONS: The body of evidence on the management of NOAF in critically ill adults is very limited and not informed by direct evidence from randomized clinical trials. Practice variation appears considerable.
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Fibrilación Atrial , Adulto , Humanos , Anticoagulantes/uso terapéutico , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Enfermedad Crítica/terapia , Alta del Paciente , Factores de RiesgoRESUMEN
Ionotropic glutamate receptors (iGluRs) are responsible for fast synaptic transmission throughout the vertebrate nervous system. Conformational changes of the transmembrane domain (TMD) underlying ion channel activation and desensitization remain poorly understood. Here, we explored the dynamics of the TMD of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type iGluRs using genetically encoded unnatural amino acid (UAA) photocross-linkers, p-benzoyl-l-phenylalanine (BzF) and p-azido-l-phenylalanine (AzF). We introduced these UAAs at sites throughout the TMD of the GluA2 receptor and characterized the mutants in patch-clamp recordings, exposing them to glutamate and ultraviolet (UV) light. This approach revealed a range of optical effects on the activity of mutant receptors. We found evidence for an interaction between the Pre-M1 and the M4 TMD helix during desensitization. Photoactivation at F579AzF, a residue behind the selectivity filter in the M2 segment, had extraordinarily broad effects on gating and desensitization. This observation suggests coupling to other parts of the receptor and like in other tetrameric ion channels, selectivity filter gating.
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Aminoácidos/metabolismo , Receptores AMPA/metabolismo , Aminoácidos/química , Azidas/metabolismo , Benzofenonas/metabolismo , Humanos , Mutagénesis , Fenilalanina/análogos & derivados , Fenilalanina/metabolismo , Dominios Proteicos , Receptor Cross-Talk , Receptores AMPA/química , Receptores de Glutamato/metabolismo , Relación Estructura-Actividad , Rayos UltravioletaRESUMEN
Involvement of the internal female reproductive organs by diffuse large B-cell lymphoma (DLBCL) is uncommon, and there are sparse data describing the outcomes of such cases. In total, 678 female patients with DLBCL staged with positron emission tomography/computed tomography and treated with rituximab-containing chemotherapy were identified from databases in Denmark, Great Britain, Australia, and Canada. Overall, 27/678 (4%) had internal reproductive organ involvement: uterus (n = 14), ovaries (n = 10) or both (n = 3). In multivariate analysis, women with uterine DLBCL experienced inferior progression-free survival and overall survival compared to those without reproductive organ involvement, whereas ovarian DLBCL was not predictive of outcome. Secondary central nervous system (CNS) involvement (SCNS) occurred in 7/17 (41%) women with uterine DLBCL (two patients with concomitant ovarian DLBCL) and 0/10 women with ovarian DLBCL without concomitant uterine involvement. In multivariate analysis adjusted for other risk factors for SCNS, uterine involvement by DLBCL remained strongly associated with SCNS (Hazard ratio 14·13, 95% confidence interval 5·09-39·25, P < 0·001). Because involvement of the uterus by DLBCL appears to be associated with a high risk of SCNS, those patients should be considered for CNS staging and prophylaxis. However, more studies are needed to determine whether the increased risk of secondary CNS involvement also applies to women with localized reproductive organ DLBCL.
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Linfoma de Células B Grandes Difuso/patología , Neoplasias Uterinas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Sistema Nervioso Central/mortalidad , Neoplasias del Sistema Nervioso Central/secundario , Bases de Datos Factuales , Supervivencia sin Enfermedad , Femenino , Humanos , Linfoma de Células B Grandes Difuso/mortalidad , Persona de Mediana Edad , Neoplasias Ováricas/complicaciones , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Pronóstico , Estudios Retrospectivos , Rituximab/uso terapéutico , Tasa de Supervivencia , Neoplasias Uterinas/complicaciones , Neoplasias Uterinas/mortalidad , Neoplasias Uterinas/patología , Adulto JovenRESUMEN
The α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) are glutamate-gated cation channels that mediate fast excitatory synaptic transmission in the central nervous system. AMPARs are tetramers formed by homo- or heteromeric assembly of GluA1-4 subunits to produce multiple subtypes with varying biophysical properties. Polyamine toxins such as joro spider toxins, philanthotoxins (PhTXs), and argiotoxins are use-dependent ion channel blockers of AMPARs widely employed as highly potent antagonists of GluA2-lacking receptor subtypes. In addition to this use, recent findings have indicated that a philanthotoxin analog, PhTX-74, can distinguish among GluA2-containing AMPAR subtypes in the presence of the prototypical transmembrane AMPAR regulatory protein γ-2 (or stargazin). Thus, PhTX-74 may be of potential use in studies of the neurobiological role of GluA2-containing subtypes. We have evaluated the pharmacological profile of PhTX-74 and related polyamine toxins at homo- and heteromeric AMPARs in the presence and absence of γ-2. Determination of IC(50) values for inhibition of glutamate-evoked currents from Xenopus oocytes expressing recombinant homo- or heteromeric combinations of GluA1, GluA2, and GluA3 in the presence of γ-2 shows that PhTX-74 inhibits homomeric GluA1 and GluA3 receptors nonselectively, with IC(50) values in the nanomolar range (252-356 nM), and heteromeric GluA1/A2 and GluA2/A3 receptors nonselectively, with IC(50) values in the micromolar range (22 µM). Thus, in contrast to earlier findings, we find that PhTX-74 cannot pharmacologically discriminate between GluA2-containing AMPAR subtypes.
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Fenoles/farmacología , Poliaminas/farmacología , Receptores AMPA/antagonistas & inhibidores , Animales , Sitios de Unión , Calcio/metabolismo , Subunidades de Proteína , Receptores AMPA/química , Receptores AMPA/clasificación , Receptores AMPA/fisiología , XenopusRESUMEN
The α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) are glutamate-gated cation channels mediating the majority of fast excitatory synaptic transmission in the central nervous system (CNS). Polyamine toxins derived from spiders and wasps are use- and voltage-dependent channel blockers of Ca(2+)-permeable AMPARs. Recent studies have suggested that AMPAR block by polyamine toxins is modulated by auxiliary subunits from the class of transmembrane AMPAR regulatory proteins (TARPs), which may have implications for their use as tool compounds in native systems. We have explored the effect of the TARP γ-2 (also known as stargazin) on the inhibitory potency of three structurally different polyamine toxins at Ca(2+)-permeable homomeric GluA1 AMPARs expressed in oocytes. We find that polyamine toxin IC50 is differentially affected by presence of stargazin depending on the efficacy of the agonists used to activate GluA1. Co-assembly of GluA1 receptors with stargazin increases the potency of the polyamine toxins when activated by the weak partial agonist kainate, but has no effect in presence of full-agonist L-glutamate (Glu) and partial agonist (RS)-willardiine.
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Canales de Calcio/fisiología , Poliaminas/farmacología , Receptores AMPA/antagonistas & inhibidores , Animales , Secuencia de Bases , Clonación Molecular , Cartilla de ADN , Modelos Moleculares , Estructura Molecular , Reacción en Cadena de la Polimerasa , Receptores AMPA/agonistas , Receptores AMPA/química , XenopusRESUMEN
Newly designed micro-solid phase extraction cartridges are now available, reflecting the increasing shift towards laboratory automation, especially in the clean-up step for the analysis of pesticide residues in food and feed. In the present study, the introduction of different sorbents on the newly designed PAL µSPE CTC cartridges was investigated for the removal of matrix interferents and the recovery of pesticides. Eight cartridges containing different sorbent combinations and different amounts were used including EMR-lipid (not activated), Z-sep, chitin, C18, PSA, and GCB. The evaluation of co-extractive removal for each cartridge showed that the optimal choice for removing fatty acids was the cartridges containing PSA and Z-sep as clean-up sorbents. However, the presence of C18 and EMR-lipid was still required for the removal of sterols and tocopherols. Two grams of sample, fish feed (FF) and rapeseed cake (RSC) were extracted using QuEChERS citrate buffer, followed by a freeze-out step. The recoveries and repeatability of QuEChERS using µ-SPE clean-up were evaluated for 216 pesticide residues (112 compounds analyzed by GC-MS/MS and 143 compounds by LC-MS/MS, from which 39 compounds were analyzed using both techniques). The best results, with recovery between 70 and 120% and RSD <20%, were achieved when FF samples were cleaned-up with 15 mg EMR-lipid and 20 mg MgSO4. This was achieved for 94% of GC-amenable compounds and 86% of LC-amenable compounds. In the case of RSC, the best results were seen when samples were cleaned-up with the cartridge containing only 20 mg Z-sep and 20 mg MgSO4. This was achieved for 88% of GC-amenable compounds and 90% of LC-amenable compounds. Although these cartridges yielded optimal results in terms of recovery, their use could require more instrument maintenance, especially for GC-MS/MS, due to the lower removal of co-extractives.
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Alimentación Animal , Residuos de Plaguicidas , Microextracción en Fase Sólida , Residuos de Plaguicidas/análisis , Microextracción en Fase Sólida/métodos , Alimentación Animal/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Contaminación de Alimentos/análisis , Extracción en Fase Sólida/métodos , AnimalesRESUMEN
Numerous studies worldwide have evaluated pesticide residues detected in urine. This review serves as a contribution to this field by presenting an overview of scientific research studies published from 2001 to 2023, including details of study characteristics and research scope. Encompassing 72 papers, the review further delves into addressing key challenges in study design and method used such as sampling and analytical approaches, results adjustments, risk assessment, estimations, and results evaluation. The review explores urinary concentrations and detection frequency of metabolites of organophosphates and pyrethroids, as well as herbicides such as 2,4-D and glyphosate and their metabolites, across various studies. The association of the results with demographic and lifestyle variables were explored. While farmers generally have higher pesticide exposure, adopting organic farming practices can reduce the levels of pesticides detected in their urine. Residence close to agricultural areas has shown high exposure in some cases. Dietary exposure is especially high among people adopting a conventionally grown plant-rich dietary pattern. A higher detection level and frequency of detection are generally found in females and children compared to males. The implications of transitioning to organic and sustainable plant-rich diets for reducing pesticide exposure and potential health benefits for both adults and children require further investigation.
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Residuos de Plaguicidas , Residuos de Plaguicidas/orina , Humanos , Femenino , Exposición a Riesgos Ambientales , Masculino , Organofosfatos/orina , Organofosfatos/metabolismo , Piretrinas/orinaRESUMEN
In order to assess compliance with maximum residue levels in foods and evaluate the exposure of the Danish population to pesticides, a comprehensive monitoring programme was conducted. The work from 2012-2017 involved testing pesticide residues in fruits, vegetables, cereals, animal product and processed commodities. The sampling strategy, mainly based on exposure calculations and previous findings, involved the collection of 13,492 samples primarily from fresh conventional and organic produces on the Danish market. The origin of the samples varied, with 34% being of Danish origin and 67% originating from EU and non-EU countries. The results revealed that residues in conventionally grown produce were detected in 54% of the fruit and vegetable samples, and 30% of the cereal samples. Additionally, residues above the maximum residue limits were found in 1.8% of these samples, most frequently in fruits. As previous years, more residues were found in samples of foreign origin compared to samples of Danish origin. Compared to earlier findings more than 40 pesticides were detected for the first time and including boscalid, imidacloprid, thiacloprid, etofenprox, and spinosad, all detected more than 100 times. The data shows that detection of PFAS pesticides has increased dramatically, from 24 in 2006 to 412 in 2022.
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Contaminación de Alimentos , Residuos de Plaguicidas , Verduras , Residuos de Plaguicidas/análisis , Dinamarca , Contaminación de Alimentos/análisis , Verduras/química , Frutas/química , Humanos , Plaguicidas/análisisRESUMEN
BACKGROUND: This study examines how shield-triggered autoinjectors (AIs), for subcutaneous drug delivery, affect injection depth. It focuses on shield size and applied force, parameters that could potentially lead to inadvertent intramuscular (IM) injections due to tissue compression. METHOD: A blinded ex-vivo study was performed to assess the impact of shield size and applied force on injection depth. Shields of 15, 20, and 30 mm diameters and forces from 2 to 10 N were investigated. The study involved 55 injections in three Landrace, Yorkshire, and Duroc (LYD) pigs, with injection depths measured with computed tomography (CT). An in-vivo study, involving 20 injections in three LYD pigs, controlled the findings, using fluoroscopy (FS) videos for depth measurement. RESULTS: The CT study revealed that smaller shield sizes significantly increased injection depth. With a 15 mm diameter shield, 10 N applied force, and 5 mm needle protrusion, the injection depth exceeded the needle length by over 3 mm. Injection depth increased with higher applied forces until a plateau was reached around 8 N. Both applied force and size were significant factors for injection depth (analysis of variance [ANOVA], P < .05) in the CT study. The FS study confirmed the ex-vivo findings in an in-vivo setting. CONCLUSIONS: The study demonstrates that shield size has a greater impact on injection depth than the applied force. While conducted in porcine tissue, the study provides useful insights into the relative effects of shield size and applied force. Further investigations in humans are needed to confirm the predicted injection depths for AIs.
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BACKGROUND: Left atrial appendage occlusion (LAAO) is performed increasingly, but long-term follow-up imaging data are lacking. AIMS: The aim of this study was to evaluate the safety and durability of the Amplatzer Amulet device >4 years after LAAO. METHODS: This was a prospective observational cohort study including 52 patients implanted with the Amplatzer Amulet device at Aarhus University Hospital, Denmark. A >4-year follow-up cardiac computed tomography (CT) scan after LAAO was performed and compared with the results from the 2-month and 12-month scans. The primary outcome was left atrial appendage (LAA) sealing based on distal LAA contrast patency and peridevice leakage (PDL), stratified into complete occlusion (grade 0 [G0]) and grade 1-3 leakage (G1-3), respectively. Secondary outcomes were low- and high-grade hypoattenuated thickening (HAT), device-related thrombosis (DRT) and device durability. RESULTS: The median (interquartile range [IQR]) follow-up time from LAAO to the latest CT scan was 5.8 years (4.5; 6.3). At 2-month (n=52), 12-month (n=27) and >4-year CT follow-ups (n=52), rates of both complete occlusion (33%, 37%, 35%) and G2 leaks (52%, 52%, 48%) remained stable. Rates of G1 leaks varied (14%, 4%, 6%) and G3 leaks rose (2%, 7%, 12%) from earliest to latest follow-up. The median left atrial (LA) volume increased from 127 mL (96; 176) to 144 mL (108; 182) and 147 mL (107; 193). No DRT was found. The structural device integrity was preserved. CONCLUSIONS: This study indicates a stable LAA sealing status throughout the follow-up period, emphasising the importance of the procedural result in avoiding PDL. Few patients displayed PDL progression, which might partly be related to LA remodelling with increasing volume. The long-term device durability appears excellent. Larger studies are warranted to confirm these findings.
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Apéndice Atrial , Fibrilación Atrial , Dispositivo Oclusor Septal , Tomografía Computarizada por Rayos X , Humanos , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/cirugía , Apéndice Atrial/fisiopatología , Masculino , Femenino , Anciano , Fibrilación Atrial/cirugía , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/diagnóstico por imagen , Estudios Prospectivos , Anciano de 80 o más Años , Resultado del Tratamiento , Estudios de Seguimiento , Persona de Mediana Edad , Cateterismo Cardíaco/métodos , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentaciónRESUMEN
Sustainable beer production requires a comprehensive assessment of potential hazards such as pesticides in both the finished product and waste streams, as these streams can be used to create high-value by-products. This study presents the tracking of 13 fungicides (azoxystrobin, boscalid, epoxiconazole, fenpropidin, fenpropimorph, fluquiconazole, flutriafol, fluxapyroxad, kresoxym-methyl, spiroxamine, propiconazole, prothioconazole-desthio, and tebuconazole), two insecticides (chlorpyrifos-methyl and deltamethrin), one herbicide (glyphosate), and one growth regulator (mepiquat) through the beer brewing process. Field-treated rye, wheat, and barley samples containing pesticide residues were used as adjunct during brewing. Samples of the beer as well as the by-products (spent grain, spent hops, trub and spent yeast) were collected and extracted with a modified QuEChERS method for pesticide residues analysis using GC-MS/MS and LC-MS/MS. Results show that an average of 58% of pesticide residues are retrieved in the by-products with the highest fraction (53%) recovered in the spent grain, 4% in trub, 1% in spent hops, no residues detected in spent yeast and 9% in the beer. This is consistent with these nonpolar pesticides tending to remain adsorbed to the spent grain during brewing. Glyphosate and mepiquat, the most polar pesticides included in this study, showed a different behavior, with the largest fraction (>80%) being retrieved in sweet wort and transferred to the beer. Processing factors were generated for each pesticide from the adjunct to the beer and to the four by-products.
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Residuos de Plaguicidas , Plaguicidas , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem , Cromatografía Liquida , Cerveza/análisis , Saccharomyces cerevisiae , Plaguicidas/análisis , GlifosatoRESUMEN
Aim: Postmortem Computed Tomography (PMCT) is gradually introduced at forensic institutes. Image reconstruction software can increase diagnostic potential in CT by increasing distinction between structures and reduction of artifacts. The aim of this study was to develop and evaluate novel image reconstruction parameters for postmortem conditions, to increase image quality and diagnostic potential of CT scans. Method: Twenty PMCT scans of deceased hereof two in severe decay were subjected to four reconstruction techniques: a standard reconstruction algorithm, the detail reconstruction algorithm and two novel algorithms based on the standard algorithm, but with different Hounsfield settings. Image quality was evaluated by visual grading analysis (VGA) by four forensic radiologist observers. Results: The VGA did not prove that any of the reconstruction techniques were superior to the others. For standard and detail, the two pre-defined reconstruction algorithms, VGA scores were indiscernible and were superior to the equally indiscernible Hounsfield reconstructions on parameters translated into Sharpness and Low Contrast Resolution. The two alternative Hounsfield settings were superior with respect to Noise and Artifacts/Beam Hardening. Conclusion: The study elucidates the possiblity for multiple reconstructions specialized for PMCT conditions, to accommodate the special conditions when working with the deceased. Despite the lack of clear improvements in the tested reconstructions, this study provides an insight into some of the possibilities of improving PMCT quality using reconstruction techniques.
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Acute pulmonary embolism (PE) is a potentially life-threatening condition that causes abrupt obstruction of the pulmonary arteries, leading to acute right heart failure. Novel diagnostic methods and catheter-directed therapies are being developed rapidly, and there is an obvious need for a realistic PE animal model that can be used for pathophysiological evaluation and preclinical testing. This protocol introduces a porcine model employing large autologous pulmonary emboli. Instrumentations are performed with minimally invasive techniques, creating a close-chest model that enables the investigation of various treatment options with high reproducibility. Three hours after drawing blood to create autologous emboli ex vivo, the induction of PE caused an immediate increase in the mean pulmonary arterial pressure (17 ± 3 mmHg to 33 ± 6 mmHg, p < 0.0001) and heart rate (50 ± 9 beats·min-1 to 63 ± 6 beats·min-1, p < 0.0003) accompanied by a decreased cardiac output (5.0 ± 0.8 L/min to 4.5 ± 0.9 L/min, p < 0.037) compared to baseline. The CT pulmonary angiography revealed multiple emboli, and the pulmonary obstruction percentage was increased compared to baseline (0% [0-0] to 57.1% [38.8-63.3], p < 0.0001). In the acute phase, the phenotype is comparable to intermediate-risk PE. The model represents a realistic and well-characterized phenotype of intermediate-risk PE and creates an opportunity to test novel diagnostic methods, interventional and pharmaceutical treatments, and hands-on training for healthcare workers in interventional procedures.
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Modelos Animales de Enfermedad , Embolia Pulmonar , Animales , Embolia Pulmonar/diagnóstico por imagen , Porcinos , Enfermedad Aguda , Angiografía por Tomografía Computarizada/métodosRESUMEN
BACKGROUND: Stomach-related disorders impose medical challenges and are associated with significant social and economic costs. The field of biomechanics is promising for understanding tissue behavior and for development of medical treatments and surgical interventions. In gastroenterology, animal models are often used when studies on humans are not possible. Often large animal models with similar anatomical characteristics (size and shape) are preferred. However, it is uncertain if stomachs from humans and large animals have similar mechanical properties. The aim of the present study is to characterize and compare hyper- and viscoelastic properties of porcine and human gastric tissue using tension and radial compression tests. METHODS: Hyperelastic and viscoelastic properties were quantified from quasi-static ramp tests and stress relaxation tests. Tension in two directions and radial compression experiments were done on intact stomach wall samples as well as on separated mucosa and muscularis layer samples from porcine and human fundus, corpus and antrum. RESULTS AND CONCLUSIONS: Similar hyper- and viscoelastic constitutive models can be used to describe porcine and human gastric tissue. In total, 19 constitutive parameters were compared and results showed significant variations between species. For example, for intact circumferential samples from antrum, the stiffness (a) and relaxation (τ1) were greater for human samples than for porcine samples (p < 0.0001). The constitutive parameters were condition-, region- and layer-dependent and no distinct pattern hereof between species was found. This indicates that different parameters must be used to describe the specific situation. The present work provides insight into porcine and human gastric radial compressive and tensile hyper- and viscoelastic properties, strengthening the inter-species relation of the biomechanical properties. Constitutive relations were established that may aid development and translation of diagnostic or therapeutic devices with computational models.
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Estómago , Humanos , Porcinos , Animales , Elasticidad , Estrés Mecánico , Modelos Animales , Fenómenos BiomecánicosRESUMEN
BACKGROUND: Thinner and shorter needles for subcutaneous administration are continuously developed. Previous studies have shown that a thinner needle causes fewer occurrences of painful needle insertions and that a shorter needle decreases the occurrence of painful intramuscular injections. However, little is known about local drug delivery in relation to needle length and thickness. This study aimed to compare deposition depth and backflow from three hypodermic needles of 3 mm 34G (0.19 mm), 5 mm 32G (0.23 mm), and 8 mm 30G (0.30 mm) in length and thickness. METHODS: Ex vivo experiments were carried out on pigs, in neck tissue comparable to human skin at typical injection sites. Six pigs were included and a total of 72 randomized injections were given, i.e. 24 subcutaneous injections given with each needle type. Accordingly, 400 µL was injected including 70% NovoRapid(®) (Novo Nordisk A/S, Bagsvµrd, Denmark) and 30% Xenetix(®) (Guerbet, Villepinte, France) contrast including 1 mg/mL Alcian blue. Surgical biopsies of injection sites were sampled and computer topographic (CT)-scanned in 3D to assess deposition and local distribution. Biopsies were prepared and stained to evaluate deposition in comparison to the CT-scanning findings. The backflow of each injection was collected with filter paper. The blue stains of filter paper were digitized and volume estimated by software calculation vs. control staining. RESULTS: CT-scanning (n = 57) and histology (n = 10) showed that, regardless of injection depth, the bulk of the injection was in the subcutaneous tissue and did not propagate from subcutis into dermis. With the 8 mm 30G needle all injections apart from one intramuscular injection were located in the subcutaneous layer. The volume depositions peaked in 4-5 mm depth for the 3 mm 34G needle, in 5-6 mm depth for the 5 mm 32G needle, and in 9-10 mm depth for the 8 mm 30G needle. In general, injection depositions evaluated by histology and CT-scans compared well for the individual biopsies. The amount of backflow (n = 69) from the 3 mm 34G needle was smaller (P < 0.05) as compared to the 5 mm 32G and the 8 mm 30G needles. Analysis showed a correlation between backflow and the needle's outer dimension with the needle diameter being the pivotal parameter. Furthermore, CT-scanning and histology confirmed that local propagation of the injection and final distribution followed a route of less mechanical resistance as determined by connective tissue barriers preset in the site of injection. CONCLUSION: Needles as short as 3 mm efficiently delivered injections into the subcutaneous target. The amount of backflow was smaller with thinner needles. Local distribution was variable and determined by mechanical barriers preset in the tissue. CT-scans and histology were concordant.
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Medios de Contraste/administración & dosificación , Medios de Contraste/farmacocinética , Inyecciones Subcutáneas/instrumentación , Agujas/clasificación , Absorción Cutánea/fisiología , Piel/metabolismo , Tomografía Computarizada por Rayos X/métodos , Animales , Diseño de Equipo , Análisis de Falla de Equipo , Inyecciones Subcutáneas/métodos , Reología , Piel/patología , Porcinos , Distribución TisularRESUMEN
Upon the European commission's request in 2013, Denmark initiated a survey of the levels of chlorate and perchlorate in agriculture products from the Danish market over a period of 4 years from 2014 to 2017. The results of the survey were used to guide decision making with a view to setting maximum levels for intra-Union trade in 2013 and reviewing and updating the levels from 2020. The results of the Danish survey and the employed analytical method are documented in this paper. In addition to the 89 domestic samples, 30 samples of foreign origin were analysed for chlorate and perchlorate, together with ten samples of baby food and seven samples of infant formula collected from the Danish market. Samples were extracted using the Quick Polar Pesticides extraction method (QuPPe) and analysed on a triple quadrupole LC-MS/MS system. The levels of both chlorate and perchlorate detected in samples originating from Denmark were lower than the current MRLs except for a single sample of lettuce. Moreover, the percentage of foreign samples that were positive for chlorate and perchlorate residues was higher than the percentage of domestic samples. The reason for the generally low levels and low frequency of chlorate and perchlorate in Danish products is most likely linked to the fact that the water supply in Denmark is 100% unchlorinated ground water. The present study shows that residues of perchlorate and chlorate are found in Danish food products at a relatively low frequency and that the levels found are below the EU's MRLs implemented in 2020.
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Cloratos , Espectrometría de Masas en Tándem , Cloratos/análisis , Cromatografía Liquida/métodos , Dinamarca , Humanos , Fórmulas Infantiles/análisis , Percloratos/análisis , Espectrometría de Masas en Tándem/métodosRESUMEN
BACKGROUND AND PURPOSE: P2X receptors are trimeric ligand-gated ion channels that open a cation-selective pore in response to ATP binding to their large extracellular domain. The seven known P2X subtypes can assemble as homotrimeric or heterotrimeric complexes and contribute to numerous physiological functions, including nociception, inflammation and hearing. The overall structure of P2X receptors is well established, but little is known about the range and prevalence of human genetic variations and the functional implications of specific domains. EXPERIMENTAL APPROACH: Here, we examine the impact of P2X2 receptor inter-subunit interface missense variants identified in the human population or by structural predictions. We test both single and double mutants through electrophysiological and biochemical approaches. KEY RESULTS: We demonstrate that predicted extracellular domain inter-subunit interfaces display a higher-than-expected density of missense variations and that the majority of mutations that disrupt putative inter-subunit interactions result in channels with higher apparent ATP affinity. Lastly, we show that double mutants at the subunit interface show significant energetic coupling, especially if located in close proximity. CONCLUSION AND IMPLICATIONS: We provide the first structural mapping of the mutational distribution across the human population in a ligand-gated ion channel and show that the density of missense mutations is constrained between protein domains, indicating evolutionary selection at the domain level. Our data may indicate that, unlike other ligand-gated ion channels, P2X2 receptors have evolved an intrinsically high threshold for activation, possibly to allow for additional modulation or as a cellular protection mechanism against overstimulation.
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Activación del Canal Iónico , Mutación Missense , Receptores Purinérgicos P2X2 , Adenosina Trifosfato/metabolismo , Humanos , Mutación , Receptores Purinérgicos P2X2/genéticaRESUMEN
The cumulative chronic dietary exposure for the Danish population were assessed using Danish food monitoring data for the period 2012-2017 and Danish food consumption data for the consumer groups children (age 1-2, age 4-6 and age 7-14 years), adults age 15-75, high consumers and consumers eating Danish produced fruit and vegetables whenever possible. Levels below the Limit of Reporting (LOR) were set to ½ LOR with correction. For risk assessment of the cumulative chronic dietary exposure we used the Hazard Index (HI) method where the Hazard Quotient (HQ) was calculated for each pesticide and summed up to a HI. The HI was calculated to be below 1 for all consumer groups; i.e. 0.36 for children age 4-6 years and 0.13 for adults, indicating that the cumulative chronic dietary pesticide exposure is unlikely to constitute a health risk for Danish consumers, even for high consumers eating 600 g or more of fruit and vegetables each day. By eating Danish produced commodities whenever possible, the HI was reduced by a factor of one third for both children and adults. 25 different commodities contributed to about 90% of the HI and to 84% of the exposure.
Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Adolescente , Adulto , Anciano , Niño , Preescolar , Dinamarca , Contaminación de Alimentos/análisis , Humanos , Lactante , Persona de Mediana Edad , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Plaguicidas/toxicidad , Medición de Riesgo , Verduras , Adulto JovenRESUMEN
Oral administration provides a simple and non-invasive approach for drug delivery. However, due to poor absorption and swift enzymatic degradation in the gastrointestinal tract, a wide range of molecules must be parenterally injected to attain required doses and pharmacokinetics. Here we present an orally dosed liquid auto-injector capable of delivering up to 4-mg doses of a bioavailable drug with the rapid pharmacokinetics of an injection, reaching an absolute bioavailability of up to 80% and a maximum plasma drug concentration within 30 min after dosing. This approach improves dosing efficiencies and pharmacokinetics an order of magnitude over our previously designed injector capsules and up to two orders of magnitude over clinically available and preclinical chemical permeation enhancement technologies. We administered the capsules to swine for delivery of clinically relevant doses of four commonly injected medications, including adalimumab, a GLP-1 analog, recombinant human insulin and epinephrine. These multi-day dosing experiments and oral administration in awake animal models support the translational potential of the system.