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1.
Nanotechnology ; 35(32)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38710174

RESUMEN

Topological crystalline insulators (TCIs) are interesting for their topological surface states, which hold great promise for scattering-free transport channels and fault-tolerant quantum computing. A promising TCI is SnTe. However, Sn-vacancies form in SnTe, causing a high hole density, hindering topological transport from the surface being measured. This issue could be relieved by using nanowires with a high surface-to-volume ratio. Furthermore, SnTe can be alloyed with Pb reducing the Sn-vacancies while maintaining its topological phase. Here we present the catalyst-free growth of monocrystalline PbSnTe in molecular beam epitaxy. By the addition of a pre-deposition stage before the growth, we have control over the nucleation phase and thereby increase the nanowire yield. This facilitates tuning the nanowire aspect ratio by a factor of four by varying the growth parameters. These results allow us to grow specific morphologies for future transport experiments to probe the topological surface states in a Pb1-xSnxTe-based platform.

2.
Radiother Oncol ; 186: 109761, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37348607

RESUMEN

PURPOSE: To quantify the difference in accuracy of adapt-to-position (ATP), adapt-to-rotation (ATR) and adapt-to-shape (ATS) workflows used in MRI-guided online adaptive radiotherapy for prostate carcinoma (PCa) by evaluating the margins required to accommodate intra-fraction motion of the clinical target volumes for prostate (CTVpros), prostate including seminal vesicles (CTVpros + sv) and gross tumor volume (GTV). MATERIALS AND METHODS: Clinical delineations of the CTVpros, CTVpros + sv and GTV of 24 patients with intermediate- and high-risk PCa, treated using ATS on a 1.5 T MR-Linac, were used for analysis. Delineations were available pre- and during beam-on. To simulate ATP and ATR workflows, we automatically generated the structures associated with these workflows using rigid transformations from the planning-MRI to the daily online MRIs. Clinical GTVs were analyzed as ATR GTVs and only ATP GTVs were simulated. Planning target volumes (PTVs) were generated with isotropic margins ranging 0.0-5.0 mm. The volumetric overlap was calculated between these PTVs and their corresponding clinical delineation on the MRI acquired during beam-on and averaged over all treatment fractions. RESULTS: The PTV margin required to cover > 95% of the CTVpros was equal (2.5 mm) for all workflows. For the CTVpros + sv, this margin increased to 5.0, 4.0 and 3.5 mm in the ATP, ATR and ATS workflow, respectively. GTV coverage improved from ATP to ATR for margins up to 4.0 mm. CONCLUSION: ATP, ATR and ATS workflows ensure equal coverage of the CTVpros for the current clinical margins. For the CTVpros + sv, ATS showed optimal performance. GTV coverage improves by additional adaptations to prostate rotations.


Asunto(s)
Neoplasias de la Próstata , Planificación de la Radioterapia Asistida por Computador , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/patología , Próstata/patología , Imagen por Resonancia Magnética , Adenosina Trifosfato , Dosificación Radioterapéutica
3.
Chemosphere ; 311(Pt 2): 137127, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36334744

RESUMEN

Petroleum refinery effluents (PRE) are wastewaters from industries associated with oil refining. Within Europe, PREs are regulated through local discharge permits and receive substantial treatment before emission. After treatment, PREs can still contain low levels of various pollutants potentially toxic to organisms. Earlier work, including whole-effluent toxicity assessments, has shown that the toxicity of permitted PREs is often limited. However, the extent to which PREs contribute to chemical pollution already present in the receiving environment is unknown. Therefore, our study aimed to assess the contribution of PREs to mixture toxic pressure in the environment, using the multi-substance potentially affected fraction of species (msPAF) as an indicator. Based on measured chemical concentrations, compiled species sensitivity distributions (SSD) and a mechanistic solubility model, msPAF levels were estimated for undiluted effluents at discharge points and diluted effluents downstream in receiving waters. Median msPAF-chronic and msPAF-acute levels of PREs at discharge points were 74% (P50) and 40% (P95), respectively. The calculated msPAF levels were reduced substantially to <5% downstream for most effluents (82%), indicating low to negligible toxicity of PREs in receiving environments beyond the initial mixing zone. Regardless of differences in endpoints and locations, hydrocarbons (mainly total petroleum hydrocarbons) and inorganics (mainly ammonia) explained at least 85% of the mixture toxic pressure. The msPAF levels of PREs were on average 2.5-4.5 orders of magnitude lower than msPAF levels derived from background pollution levels, suggesting that PREs were minor contributors to the toxic pressure in the environment. This study presents a generic methodology for quantifying the potential toxic pressure of PREs in the environment, identifying hotspots where more effective wastewater treatment could be needed. We explicitly discuss the uncertainties for further refinement and development of the method.


Asunto(s)
Contaminantes Ambientales , Petróleo , Contaminantes Químicos del Agua , Petróleo/toxicidad , Contaminación Ambiental , Aguas Residuales , Hidrocarburos , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
4.
Ann Rheum Dis ; 81(5): 644-652, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35144926

RESUMEN

OBJECTIVE: To comparatively analyse the aberrant affinity maturation of the antinuclear and rheumatoid factor (RF) B cell repertoires in blood and tissues of patients with Sjögren's syndrome (SjS) using an integrated omics workflow. METHODS: Peptide sequencing of anti-Ro60, anti-Ro52, anti-La and RF was combined with B cell repertoire analysis at the DNA, RNA and single cell level in blood B cell subsets, affected salivary gland and extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT) of patients with SjS. RESULTS: Affected tissues contained anti-Ro60, anti-Ro52, anti-La and RF clones as a small part of a polyclonal infiltrate. Anti-Ro60, anti-La and anti-Ro52 clones outnumbered RF clones. MALT lymphoma tissues contained monoclonal RF expansions. Autoreactive clones were not selected from a restricted repertoire in a circulating B cell subset. The antinuclear antibody (ANA) repertoires displayed similar antigen-dependent and immunoglobulin (Ig) G1-directed affinity maturation. RF clones displayed antigen-dependent, IgM-directed and more B cell receptor integrity-dependent affinity maturation. This coincided with extensive intra-clonal diversification in RF-derived lymphomas. Regeneration of clinical disease manifestations after rituximab coincided with large RF clones, which not necessarily belonged to the lymphoma clone, that displayed continuous affinity maturation and intra-clonal diversification. CONCLUSION: The ANA and RF repertoires in patients with SjS display tissue-restricted, antigen-dependent and divergent affinity maturation. Affinity maturation of RF clones deviates further during RF clone derived lymphomagenesis and during regeneration of the autoreactive repertoire after temporary disruption by rituximab. These data give insight into the molecular mechanisms of autoreactive inflammation in SjS, assist MALT lymphoma diagnosis and allow tracking its response to rituximab.


Asunto(s)
Linfoma de Células B de la Zona Marginal , Proteogenómica , Síndrome de Sjögren , Linfocitos B/inmunología , Linfocitos B/metabolismo , Humanos , Inmunoglobulina G/inmunología , Factor Reumatoide/metabolismo , Rituximab/uso terapéutico , Síndrome de Sjögren/inmunología
5.
Integr Environ Assess Manag ; 17(5): 1025-1036, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33615680

RESUMEN

Assessment and management of effluent discharges are key to avoiding environmental deterioration. Often compliance with discharge regulations and permits is based on a limited set of chemical parameters, while information on whole effluent hazardous properties (toxicity, bioaccumulation potential, persistence) and environmental risks is lacking. The need to collect those data and to become more effective in quickly identifying high-risk activities, without extensive laboratory testing, has led to the development of screening tools to complement information on chemical composition. A simple, Tier 1 screening "toolbox" is proposed which is comprised of solid-phase microextraction with gas chromatographic (SPME-GC) analysis, the in-vitro ecotoxicity assay Microtox, and a simple weathering assay. When combined with dilution modeling, screening-level risk assessments can be performed, providing additional lines of evidence to support a weight of evidence type of analysis. Application of the toolbox enables prioritization of discharges that may be deemed to require higher tier assessment. The toolbox was trialed on a number of produced water samples collected from offshore oil and gas facilities and effluents from petroleum processing and manufacturing sites. In contrast to what has been reported for petroleum products, results showed only moderate correlation between bioavailable hydrocarbons (bHCs) and toxicity, which might be related to the possible presence of toxic contaminants from other chemical classes or to methodological issues such as suboptimal conditions during transport. The methods employed were quick, inexpensive, and simple to conduct. They require relatively small volumes of sample, which is especially advantageous when evaluating discharges from remote offshore facilities. The toolbox adds valuable information on whole effluent properties to existing data, for example, on chemical composition, which can improve understanding of which discharges are more likely to pose a risk to the environment and so require further investigation or risk management. Integr Environ Assess Manag 2021;17:1025-1036. © 2021 Shell International B.V. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Asunto(s)
Petróleo , Contaminantes Químicos del Agua , Ecotoxicología , Monitoreo del Ambiente , Hidrocarburos , Industria del Petróleo y Gas , Medición de Riesgo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
6.
Chemosphere ; 263: 128081, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33297080

RESUMEN

Distribution and elimination of petroleum products can be predicted in aerobic wastewater treatment plants (WWTPs) using models such as multimedia fate model SimpleTreat. An advantage of the SimpleTreat model is that it only requires a few basic properties of a chemical in wastewater to calculate partitioning, biodegradation and ultimately emissions to air, surface water and produced sludge. The SimpleTreat model structure reflects a WWTP scheme. However, refinery WWTPs typically incorporate more advanced treatment processes such as dissolved air flotation (DAF), a process that clarifies wastewaters by the removal of suspended matter such as oil or solids. The objective of this work was to develop a WWTP removal model that includes DAF treatment. To understand how including a DAF in the model affects the predicted concentrations of petroleum constituents in effluent, we replaced the primary sedimentation module in SimpleTreat with a module simulating DAF. Subsequently, we compared results from the WWTP-DAF model with results obtained with the original SimpleTreat model for a library of over 1500 representative hydrocarbon constituents. The increased air-water exchange in a WWTP-DAF unit resulted in higher predicted removal of volatile constituents. Predicted removal with DAF was on average 17% larger than removal with primary sedimentation. We compared modelled results with measured removal data from the literature, which supported that this model refinement continues to improve the technical basis of assessment of petroleum products.


Asunto(s)
Petróleo , Aguas del Alcantarillado , Biodegradación Ambiental , Hidrocarburos , Eliminación de Residuos Líquidos , Aguas Residuales
7.
Minerva Anestesiol ; 86(9): 930-938, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32538578

RESUMEN

BACKGROUND: The incidence of delirium following open abdominal aortic aneurysm (AAA) surgery is significant, with incidence rates ranging from 12% to 33%. However, it remains unclear on what level of care a delirium develops in AAA patients. The aim of this study was to investigate the incidence of delirium in the ICU and on the surgical ward after AAA surgery. METHODS: A single-center retrospective cohort study was conducted that included all patients treated electively for an open AAA repair and patients who underwent emergency treatment for a ruptured AAA between 2013 and 2018. The diagnosis of delirium was verified by a psychiatrist or geriatrician using the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) criteria. The incidence of delirium was calculated. Cox proportional hazards regression analyses were used to analyze 6- and 12-month survival. RESULTS: A total of 135 patients were included, 46 patients (34%) had a delirium during admission. Of these, 30 patients (65%) developed a delirium in the ICU and 16 patients (35%) on the surgical ward. There was no significant difference in six months and twelve months mortality between the ICU and ward delirium groups (HR=1.64, 95% CI: 0.33-8.13, and HR=1.12, 95% CI: 0.28-4.47, respectively). CONCLUSIONS: Delirium frequently occurs in patients who undergo AAA surgery. This study demonstrated that patients on the surgical ward remain at risk of developing a delirium after ICU dismissal. Patients with ICU delirium differ in clinical characteristics and outcomes from patients with a delirium on the surgical ward.


Asunto(s)
Aneurisma de la Aorta Abdominal , Delirio , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/cirugía , Delirio/epidemiología , Delirio/etiología , Tratamiento de Urgencia , Humanos , Unidades de Cuidados Intensivos , Estudios Retrospectivos , Factores de Riesgo
8.
Eur J Nucl Med Mol Imaging ; 47(4): 798-806, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31399801

RESUMEN

PURPOSE: As an alternative to technetium-99m-macroaggregated albumin (99mTc-MAA), a scout dose of holmium-166 (166Ho) microspheres can be used prior to 166Ho-radioembolization. The use of identical particles for pre-treatment and treatment procedures may improve the predictive value of pre-treatment analysis of distribution. The aim of this study was to analyze the agreement between 166Ho-scout and 166Ho-therapeutic dose in comparison with the agreement between 99mTc-MAA and 166Ho-therapeutic dose. METHODS: Two separate scout dose procedures were performed (99mTc-MAA and 166Ho-scout) before treatment in 53 patients. First, qualitative assessment was performed by two blinded nuclear medicine physicians who visually rated the agreement between the 99mTc-MAA, 166Ho-scout, and 166Ho-therapeutic dose SPECT-scans (i.e., all performed in the same patient) on a 5-point scale. Second, agreement was measured quantitatively by delineating lesions and normal liver on FDG-PET/CT. These volumes of interest (VOIs) were co-registered to the SPECT/CT images. The predicted absorbed doses (based on 99mTc-MAA and 166Ho-scout) were compared with the actual absorbed dose on post-treatment SPECT. RESULTS: A total of 23 procedures (71 lesions, 22 patients) were included for analysis. In the qualitative analysis, 166Ho-scout was superior with a median score of 4 vs. 2.5 for 99mTc-MAA (p < 0.001). The quantitative analysis showed significantly narrower 95%-limits of agreement for 166Ho-scout in comparison with 99mTc-MAA when evaluating lesion absorbed dose (- 90.3 and 105.3 Gy vs. - 164.1 and 197.0 Gy, respectively). Evaluation of normal liver absorbed dose did not show difference in agreement between both scout doses and 166Ho-therapeutic dose (- 2.9 and 5.5 Gy vs - 3.6 and 4.1 Gy for 99mTc-MAA and 166Ho-scout, respectively). CONCLUSIONS: In this study, 166Ho-scout was shown to have a superior predictive value for intrahepatic distribution in comparison with 99mTc-MAA.


Asunto(s)
Embolización Terapéutica , Neoplasias Hepáticas , Albúminas , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Microesferas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único , Radioisótopos de Itrio
9.
Eur J Vasc Endovasc Surg ; 59(4): 598-605, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31870693

RESUMEN

OBJECTIVE: Delirium is associated with adverse outcomes, such as increased mortality and prolonged hospital stay. Information on the risk factors for delirium in elderly patients with critical limb ischaemia (CLI) is scarce. The aim of this study was to analyse the incidence of delirium and to identify risk factors for delirium in elderly patients undergoing surgical or endovascular treatment. METHODS: A retrospective cohort study was conducted including patients aged ≥ 65 years undergoing surgical or endovascular treatment for CLI between January 2013 and June 2018. Delirium was scored using the DOSS (Delirium Observation Screening Scale) and the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) criteria. Risk factors for delirium were analysed using logistic regression. The discriminative ability of the model was calculated using the area under the receiver operating characteristics (AUROC) curve. RESULTS: In total, 392 patients were included, of which 70 (17.9%) developed delirium. Factors associated with an increased risk of delirium were: age, odds ratio (OR) 1.05 (95% confidence interval (CI) 1.0-1.1), history of femoral endarterectomy, OR 4.7 (95% CI 1.5-15), physical impairment, OR 2.2 (95% CI 1.1-4.5), history of delirium, OR 2.7 (95% CI 1.4-5.3), general anaesthesia, OR 2.6 (95% CI 1.2-5.7) and pre-operative anaemia, OR 5.9 (95% CI 2.3-15). The AUROC was .82 (95% CI 0.76-0.87, p < .001). Delirium was associated with more respiratory, renal and surgical complications, as well as a prolonged hospital stay and a more frequent discharge to a nursing home. CONCLUSION: Delirium occurs frequently in patients with critical limb ischaemia undergoing any type of invasive treatment. This study identified multiple risk factors for delirium that may be helpful to delineate patients susceptible to its development.


Asunto(s)
Delirio , Extremidades/cirugía , Isquemia/cirugía , Complicaciones Posoperatorias/epidemiología , Anciano , Anciano de 80 o más Años , Endarterectomía/efectos adversos , Femenino , Humanos , Incidencia , Tiempo de Internación/estadística & datos numéricos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
10.
J Vasc Surg ; 71(6): 2065-2072.e2, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31711729

RESUMEN

OBJECTIVE: To aid physicians in the process of shared decision-making, many predictive models for critical limb ischemia (CLI) have been constructed. However, none of these models is in widespread use. Predicting survival outcomes for a specific individual may be used to guide treatment selection. The aim of this study was to construct a 6-month survival-predicting model representative of elderly patients with CLI undergoing surgical or endovascular treatment. METHODS: An observational cohort study including all patients with CLI aged ≥65 years who underwent surgical or endovascular treatment of CLI between January 2013 and June 2018 was conducted. The model to predict survival at 6 months was based on a multivariable Cox proportional hazards regression model and a penalized likelihood method. The performance of the model was judged by means of the area under the receiver operating characteristic curve. RESULTS: In total, 449 patients were included in the study population. The median age was 76 years (range, 65-97 years), and 52.8% of the population was male. Surgical treatment was performed in 303 patients (67.5%), and 146 underwent endovascular treatment (32.5%). The estimated 30-day survival was 92.7% (standard error [SE], 1.2%); 6-month survival, 80% (SE, 1.9%); and 12-month survival, 71% (SE, 2.1%). Variables with the strongest association with 6-month mortality were age, living in a nursing home, physical impairment, and American Society of Anesthesiologists class. The area under the receiver operating characteristic curve of the 6-month mortality model was 0.81 (95% confidence interval, 0.76-0.85; P < .001). CONCLUSIONS: A prediction model constructed for 6-month mortality of elderly patients undergoing surgical or endovascular treatment of CLI showed that age, living in a nursing home, physical impairment, and American Society of Anesthesiologists class have the highest association with an increase in mortality. These factors may be used to identify patients at risk for mortality in shared decision-making.


Asunto(s)
Reglas de Decisión Clínica , Procedimientos Endovasculares/mortalidad , Isquemia/terapia , Enfermedad Arterial Periférica/terapia , Procedimientos Quirúrgicos Vasculares/mortalidad , Factores de Edad , Anciano , Anciano de 80 o más Años , Enfermedad Crítica , Procedimientos Endovasculares/efectos adversos , Femenino , Estado de Salud , Hogares para Ancianos , Humanos , Isquemia/diagnóstico , Isquemia/mortalidad , Masculino , Casas de Salud , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/mortalidad , Valor Predictivo de las Pruebas , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos
11.
Mar Environ Res ; 144: 250-254, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30686565

RESUMEN

With the level of industrial activities increasing in Arctic areas it is crucial to assure that dedicated oil spill response capabilities and strategies are available for deployment in this region. To further build on existing research and improve technologies and methodologies for Arctic oil spill response, nine oil and gas companies established the Arctic Response Technology Joint Industry Program (ART-JIP) in 2012 with the goal to advance Arctic oil spill response strategies and equipment as well as to increase understanding of potential impacts of oil on the Arctic marine environment. As part of the environmental effects research program of the ART-JIP a comprehensive review of the environmental impacts arising from both the oil spill itself and the countermeasures activities was executed. A number of research activities were identified to improve the knowledge base for using a Net Environmental Benefit Analysis (NEBA) in the Arctic. As a follow-up of the review modelling-, laboratory- and field studies were conducted. The data collected from the review and the additional studies have been organized in an information tool to support tool Arctic NEBA. Results from the studies have improved the understanding of what happens to oil once frozen into ice, how the microbe communities are reacting to oil in ice and what the exposure potential and effects are on the marine organisms that live in association with the ice. This output from the ART-JIP will help managing oil spill impacts and will assist in the definition of a response strategy that minimizes effects to the environment.


Asunto(s)
Monitoreo del Ambiente , Contaminación por Petróleo/efectos adversos , Regiones Árticas , Biodegradación Ambiental , Clima , Ecotoxicología , Ambiente , Hielo , Industrias
12.
Eur J Cardiothorac Surg ; 55(6): 1225-1227, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30312383

RESUMEN

A secondary aortoduodenal fistula is a rare but a severe late complication after prosthetic abdominal aortic surgery. Currently, there is little consensus regarding the right treatment due to high mortality and morbidity rates. We report the case of a haemodynamically unstable patient with haematemesis on the basis of a secondary aortoduodenal fistula. He was successfully treated by staged stent graft placement followed by surgical graft excision and autogenous deep vein reconstruction. In haemodynamically unstable patients or in patients where open repair is not feasible in the acute setting of secondary aortoduodenal fistula, we advocate the use of a 2-staged endovascular and surgical approach to improve short- and long-term outcomes.


Asunto(s)
Enfermedades de la Aorta/cirugía , Implantación de Prótesis Vascular/métodos , Enfermedades Duodenales/cirugía , Procedimientos Endovasculares/métodos , Fístula Intestinal/cirugía , Stents , Fístula Vascular/cirugía , Anciano , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/cirugía , Enfermedades de la Aorta/diagnóstico , Aortografía , Enfermedades Duodenales/diagnóstico , Humanos , Fístula Intestinal/diagnóstico , Fístula Intestinal/etiología , Masculino , Reoperación , Fístula Vascular/diagnóstico , Fístula Vascular/etiología
13.
Rheumatology (Oxford) ; 58(3): 536-546, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30508140

RESUMEN

OBJECTIVE: To investigate the role of AXL, a member of the anti-inflammatory TYRO3, AXL MER (TAM) receptor family, in arthritis. METHODS: KRN serum transfer arthritis was induced in Axl-/- and wild-type mice. Knee and ankle joints were scored macro- and microscopically. Synovial gene and protein expression of Axl was determined in naïve and TGF-ß1-overexpressing joints. AXL expression was determined in M1-like or M2-like macrophages and RA synovium. Human macrophages, fibroblasts and synovial micromasses were stimulated with TGF-ß1 or the AXL inhibitor R428. RESULTS: Ankle joints of Axl-/- mice showed exacerbated arthritis pathology, whereas no effect of Axl gene deletion was observed on gonarthritis pathology. To explain this spatial difference, we examined the synovium of naïve mice. In contrast to the knee, the ankle synovial cells prominently expressed AXL. Moreover, the M2-like macrophage phenotype was the dominant cell type in the naïve ankle joint. Human M2-like macrophages expressed higher levels of AXL and blocking AXL increased their inflammatory response. In the murine ankle synovium, gene expression of Tgfb1 was increased and Tgb1 correlated with Axl. Moreover, TGFB1 and AXL expression also correlated in human RA synovium. In human macrophages and synovial micromasses, TGF-ß1 enhanced AXL expression. Moreover, TGF-ß1 overexpression in naïve murine knee joints induced synovial AXL expression. CONCLUSION: Differences in synovial AXL expression are in accordance with the observation that AXL dampens arthritis in ankle, but not in knee joints. We provide evidence that the local differences in AXL expression could be due to TGF-ß1, and suggest similar pathways operate in RA synovium.


Asunto(s)
Artritis Experimental/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Membrana Sinovial/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Articulación del Tobillo/metabolismo , Artritis Experimental/genética , Fibroblastos/metabolismo , Humanos , Articulación de la Rodilla/metabolismo , Macrófagos/metabolismo , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Tirosina Quinasa del Receptor Axl
14.
ALTEX ; 36(1): 18-28, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30303512

RESUMEN

Therapeutic agents that are used by patients with rheumatic and musculoskeletal diseases were originally developed and tested in animal models, and although retrospective studies show a limited predictive value, it could be explained by the fact that there are no good in vitro alternatives. In this study, we developed a 3-dimensional synovial membrane model made of either human primary synovial cell suspensions or a mix of primary fibroblast-like synoviocytes and CD14+ mononuclear cells. We analyzed the composition of the mature micromasses by immunohistochemical staining and flow cytometry and show that the outer surface forms a lining layer consisting out of fibroblast-like and macrophage-like cells, reflecting the in vivo naïve synovial membrane. To recreate the affected synovial membrane in rheumatoid arthritis (RA), the micromasses were exposed to the pro-inflammatory cytokine Tumor Necrosis Factor Alpha (TNF-α). This led to increased pro-inflammatory cytokine expression and production and to hyperplasia of the membrane. To recreate the synovial membrane in osteoarthritis (OA), the micromasses were exposed to Transforming Growth Factor Beta (TGF-ß). This led to fibrosis-like changes of the membrane, including increased Alpha Smooth Muscle Actin and increased expression of fibrosis-related genes PLOD2 and COL1A1. Interestingly, the macrophages in the micromass showed phenotypic plasticity as prolonged TNF-α or TGF-ß stimulation strongly reduced the occurrence of Cluster of Differentiation 163-positive M2-like macrophages. We showed the plasticity of the micromasses as a synovial model for studying RA and OA pathology and propose that the synovial lining micromass system can be a good alternative for testing drugs.


Asunto(s)
Fibroblastos/fisiología , Leucocitos Mononucleares/fisiología , Membrana Sinovial/patología , Andamios del Tejido , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Imagenología Tridimensional , Inflamación/inducido químicamente , Inflamación/metabolismo , Receptores de Lipopolisacáridos/metabolismo
15.
PeerJ ; 6: e4771, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29868252

RESUMEN

OBJECTIVE: Tumor necrosis factor-inducible gene 6 (TSG-6) has anti-inflammatory and chondroprotective effects in mouse models of inflammatory arthritis. Because cartilage damage and inflammation are also observed in osteoarthritis (OA), we determined the effect of viral overexpression of TSG-6 in experimental osteoarthritis. METHODS: Bone marrow-derived cells were differentiated to multinucleated osteoclasts in the presence of recombinant TSG-6 or after transduction with a lentiviral TSG-6 expression vector. Multi-nucleated osteoclasts were analyzed after tartrate resistant acid phosphatase staining and resorption activity was determined on dentin slices. Collagenase-induced osteoarthritis (CIOA) was induced in C57BL/6 mice after intra-articular injection of an adenoviral TSG-6 or control luciferase expression vector. Inflammation-related protease activity was measured using bioluminescent Prosense probes. After a second adenovirus injection, cartilage damage was assessed in histological sections stained with Safranin-O. Ectopic bone formation was scored in X-ray images of the affected knees. RESULTS: TSG-6 did not inhibit the formation of multi-nucleated osteoclasts, but caused a significant reduction in the resorption activity on dentin slices. Adenoviral TSG-6 gene therapy in CIOA could not reduce the cartilage damage compared to the luciferase control virus and no significant difference in inflammation-related protease activity was noted between the TSG-6 and control treated group. Instead, X-ray analysis and histological analysis revealed the presence of ectopic bone formation in the TSG-6 treated group. CONCLUSION: Gene therapy based on the expression of TSG-6 could not provide cartilage protection in experimental osteoarthritis, but instead resulted in increased ectopic bone formation.

16.
Energy Fuels ; 32(1): 822-838, 2018 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-29910533

RESUMEN

Since its discovery, the flameless combustion (FC) regime has been a promising alternative to reduce pollutant emissions of gas turbine engines. This combustion mode is characterized by well-distributed reaction zones, which potentially decreases temperature gradients, acoustic oscillations, and NO x emissions. Its attainment within gas turbine engines has proved to be challenging because previous design attempts faced limitations related to operational range and combustion efficiency. Along with an aircraft conceptual design, the AHEAD project proposed a novel hybrid engine. One of the key features of the proposed hybrid engine is the use of two combustion chambers, with the second combustor operating in the FC mode. This novel configuration would allow the facilitation of the attainment of the FC regime. The conceptual design was adapted to a laboratory scale combustor that was tested at elevated temperature and atmospheric pressure. In the current work, the emission behavior of this scaled combustor is analyzed using computational fluid dynamics (CFD) and chemical reactor network (CRN). The CFD was able to provide information with the flow field in the combustor, while the CRN was used to model and predict emissions. The CRN approach allowed the analysis of the NO x formation pathways, indicating that the prompt NO x was the dominant pathway in the combustor. The combustor design can be improved by modifying the mixing between fuel and oxidizer as well as the split between combustion and dilution air.

17.
Front Immunol ; 9: 742, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29706963

RESUMEN

Objective: Rheumatoid arthritis (RA) is a chronic and progressive joint disease. It appears that anti-inflammatory feedback mechanisms that could restrain joint inflammation and restore homeostasis are insufficient to perform this control. In this study, we investigated the contribution of the MER tyrosine kinase-mediated anti-inflammatory response on arthritis and whether targeting MER could be a valid approach to treat RA. Methods: KRN serum transfer arthritis (KRN STA) was induced in either Mertk-deficient mice or in mice that adenovirally overexpressed Pros1. Human synovial micromasses were treated with MER-specific antibodies or PROS1. Collagen-induced arthritis (CIA) mice were treated with MER-specific agonistic antibodies or by viral overexpression of Pros1. Results: Mertk-/- mice showed exacerbated arthritis pathology, whereas Pros1 overexpression diminished joint pathology in KRN STA. Human synovial micromasses challenged with MER-specific antibodies enhanced the secretion of inflammatory cytokines, whereas stimulating MER with PROS1 reduced the secretion of these cytokines, confirming the protective role of MER. Next, we treated CIA mice with MER-specific agonistic antibodies, and this unexpectedly resulted in exacerbated arthritis pathology. This was associated with increased numbers of apoptotic cells in their knee joints and higher serum levels of interleukin (IL)-16C, a cytokine released by secondary necrotic neutrophils. Apoptotic cell numbers and IL-16C levels were enhanced during arthritis in Mertk-/- mice and reduced in Pros1-overexpressing mice. Conclusion: MER plays a protective role during joint inflammation and activating MER by its ligand PROS1 ameliorates disease. Treatment of mice with MER receptor agonistic antibodies is deleterious due to its counterproductive effect of blocking efferocytosis in the arthritic joint.


Asunto(s)
Artritis Experimental/inmunología , Artritis Reumatoide/inmunología , Proteínas Portadoras/fisiología , Tirosina Quinasa c-Mer/fisiología , Animales , Artritis Experimental/patología , Artritis Reumatoide/patología , Proteínas de Unión al Calcio , Línea Celular , Citocinas/inmunología , Modelos Animales de Enfermedad , Femenino , Humanos , Articulación de la Rodilla/inmunología , Articulación de la Rodilla/patología , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Noqueados , Membrana Sinovial/inmunología
18.
Mar Environ Res ; 127: 11-23, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28041674

RESUMEN

The aim of this paper is to bridge gaps between biomarker and whole organism responses related to oil based offshore discharges. These biomarker bridges will facilitate acceptance criteria for biomarker data linked to environmental risk assessment and translate biomarker results to higher order effects. Biomarker based species sensitivity distributions (SSDbiomarkers) have been constructed for relevant groups of biomarkers based on laboratory data from oil exposures. SSD curves express the fraction of species responding to different types of biomarkers. They have been connected to SSDs for whole organism responses (WORs) constructed in order to relate the SSDbiomarkers to animal fitness parameters that are commonly used in environmental risk assessment. The resulting SSD curves show that biomarkers and WORs can be linked through their potentially affected fraction of species (PAF) distributions, enhancing the capability to monitor field parameters with better correlation to impact and risk assessment criteria and providing improved chemical/biological integration.


Asunto(s)
Organismos Acuáticos/fisiología , Biomarcadores , Monitoreo del Ambiente/métodos , Contaminación por Petróleo/estadística & datos numéricos , Petróleo/análisis , Medición de Riesgo , Especificidad de la Especie
19.
PLoS One ; 11(11): e0167076, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27870898

RESUMEN

Osteoarthritis (OA) is a degenerative joint disease affecting cartilage and is the most common form of arthritis worldwide. One third of OA patients have severe synovitis and less than 10% have no evidence of synovitis. Moreover, synovitis is predictive for more severe disease progression. This offers a target for therapy but more research on the pathophysiological processes in the synovial tissue of these patients is needed. Functional studies performed with synovial tissue will be more approachable when this material, that becomes available by joint replacement surgery, can be stored for later use. We set out to determine the consequences of slow-freezing of human OA synovial tissue. Therefore, we validated a method that can be applied in every routine laboratory and performed a comparative study of five cryoprotective agent (CPA) solutions. To determine possible deleterious cryopreservation-thaw effects on viability, the synovial tissue architecture, metabolic activity, RNA quality, expression of cryopreservation associated stress genes, and expression of OA characteristic disease genes was studied. Furthermore, the biological activity of the cryopreserved tissue was determined by measuring cytokine secretion induced by the TLR ligands lipopolysaccharides and Pam3Cys. Compared to non frozen synovium, no difference in cell and tissue morphology could be identified in the conditions using the CS10, standard and CryoSFM CPA solution for cryopreservation. However, we observed significantly lower preservation of tissue morphology with the Biofreeze and CS2 media. The other viability assays showed trends in the same direction but were not sensitive enough to detect significant differences between conditions. In all assays tested a clearly lower viability was detected in the condition in which synovium was frozen without CPA solution. This detailed analysis showed that OA synovial tissue explants can be cryopreserved while maintaining the morphology, viability and phenotypical response after thawing, offering enhanced opportunities for human in vitro studies.


Asunto(s)
Criopreservación/métodos , Osteoartritis , Membrana Sinovial , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Osteoartritis/metabolismo , Osteoartritis/patología , Membrana Sinovial/metabolismo , Membrana Sinovial/patología
20.
Arthritis Res Ther ; 18: 186, 2016 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-27519904

RESUMEN

BACKGROUND: Gene therapy has the potential to provide long-term production of therapeutic proteins in the joints of osteoarthritis (OA) patients. The objective of this study was to analyse the therapeutic potential of disease-inducible expression of anti-inflammatory interleukin-10 (IL-10) in the three-dimensional micromass model of the human synovial membrane. METHODS: Synovial tissue samples from OA patients were digested and the cells were mixed with Matrigel to obtain 3D micromasses. The CXCL10 promoter combined with the firefly luciferase reporter in a lentiviral vector was used to determine the response of the CXCL10 promoter to tumour necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß) and lipopolysaccharide (LPS). The effects of recombinant IL-10 on gene expression were determined by quantitative PCR. The production of IL-10 from the CXCL10p-IL10 vector and the effects on pro-inflammatory cytokine production were assessed by multiplex ELISA. RESULTS: Micromasses made from whole synovial membrane cell suspensions form a distinct surface composition containing macrophage and fibroblast-like synoviocytes thus mimicking the synovial lining. This lining can be transduced by lentiviruses and allow CXCL-10 promoter-regulated transgene expression. Adequate amounts of IL-10 transgene were produced after stimulation with pro-inflammatory factors able to reduce the production of synovial IL-1ß and IL-6. CONCLUSIONS: Synovial micromasses are a suitable model to test disease-regulated gene therapy approaches and the CXCL10p-IL10 vector might be a good candidate to decrease the inflammatory response implicated in the pathogenesis of OA.


Asunto(s)
Terapia Genética/métodos , Interleucina-10/biosíntesis , Osteoartritis/inmunología , Membrana Sinovial/inmunología , Técnicas de Cultivo de Tejidos/métodos , Quimiocina CXCL10/genética , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Vectores Genéticos , Humanos , Interleucina-10/inmunología , Lentivirus , Masculino , Microscopía Confocal , Osteoartritis/metabolismo , Regiones Promotoras Genéticas , Reacción en Cadena en Tiempo Real de la Polimerasa , Membrana Sinovial/metabolismo
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