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3.
Sci Robot ; 7(63): eabk2119, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35108023

RESUMEN

Soft robotics greatly benefits from nature as a source of inspiration, introducing innate means of safe interaction between robotic appliances and living organisms. In contrast, the materials involved are often nonbiodegradable or stem from nonrenewable resources, contributing to an ever-growing environmental footprint. Furthermore, conventional manufacturing methods, such as mold casting, are not suitable for replicating or imitating the complexity of nature's creations. Consequently, the inclusion of sustainability concepts alongside the development of new fabrication procedures is required. We report a customized 3D-printing process based on fused deposition modeling, printing a fully biodegradable gelatin-based hydrogel (biogel) ink into dimensionally stable, complex objects. This process enables fast and cost-effective prototyping of resilient, soft robotic applications from gels that stretch to six times their original length, as well as an accessible recycling procedure with zero waste. We present printed pneumatic actuators performing omnidirectional movement at fast response times (less than a second), featuring integrated 3D-printed stretchable waveguides, capable of both proprio- and exteroception. These soft devices are endowed with dynamic real-time control capable of automated search-and-wipe routines to detect and remove obstacles. They can be reprinted several times or disposed of hazard-free at the end of their lifetime, potentially unlocking a sustainable future for soft robotics.


Asunto(s)
Hidrogeles , Impresión Tridimensional , Robótica/métodos , Materiales Biocompatibles , Materiales Biomiméticos , Diseño de Equipo , Gelatina , Humanos , Tinta , Fenómenos Ópticos , Impresión Tridimensional/instrumentación , Robótica/instrumentación , Resistencia a la Tracción
4.
Nat Commun ; 11(1): 2126, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32358532

RESUMEN

Many inland waters exhibit complete or partial desiccation, or have vanished due to global change, exposing sediments to the atmosphere. Yet, data on carbon dioxide (CO2) emissions from these sediments are too scarce to upscale emissions for global estimates or to understand their fundamental drivers. Here, we present the results of a global survey covering 196 dry inland waters across diverse ecosystem types and climate zones. We show that their CO2 emissions share fundamental drivers and constitute a substantial fraction of the carbon cycled by inland waters. CO2 emissions were consistent across ecosystem types and climate zones, with local characteristics explaining much of the variability. Accounting for such emissions increases global estimates of carbon emissions from inland waters by 6% (~0.12 Pg C y-1). Our results indicate that emissions from dry inland waters represent a significant and likely increasing component of the inland waters carbon cycle.

5.
Curr Oncol ; 26(6): e766-e772, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31896947

RESUMEN

Introduction: Retroperitoneal sarcoma (rps) encompasses a heterogeneous group of malignancies with a high recurrence rate after resection. Neoadjuvant radiotherapy (nrt) is often used in the hope of sterilizing margins and decreasing local recurrence after excision. We set out to compare local recurrence-free survival (lrfs) and overall survival (os) in patients treated with or without nrt before resection. Methods: Patients diagnosed with rps from February 1990 to October 2014 were identified in the Alberta Cancer Registry. Patients with complete gross resection of rps and no distant disease were included. Patient, tumour, treatment, and outcomes data were abstracted in a primary chart review. Baseline characteristics were compared using the Wilcoxon nonparametric test for continuous data and the Fisher exact test for dichotomous and categorical data. Survival was analyzed using Kaplan-Meier curves with log-rank test. Cox regression was performed to control for age, sex, tumour size, tumour grade, date of diagnosis, multivisceral resection, and intraoperative rupture. Results: Resection alone was performed in 62 patients, and resection after nrt, in 40. Use of nrt was associated with multivisceral resection and negative microscopic margins. On univariate analysis, nrt was associated with superior median lrfs (89.3 months vs. 28.4 months, p = 0.04) and os (119.4 months vs. 75.9 months, p = 0.04). On multivariate analysis, nrt, younger age, and lower tumour grade predicted improved lrfs and os; sex, tumour size, date of diagnosis, multivisceral resection, and tumour rupture did not. Conclusions: In this population-based study, nrt was associated with superior lrfs and os on both univariate and multivariate analysis. When feasible, nrt should be considered until a randomized controlled trial is completed.


Asunto(s)
Neoplasias Retroperitoneales/radioterapia , Neoplasias Retroperitoneales/cirugía , Sarcoma/radioterapia , Sarcoma/cirugía , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Clasificación del Tumor , Neoplasias Retroperitoneales/mortalidad , Neoplasias Retroperitoneales/patología , Sarcoma/mortalidad , Sarcoma/patología , Carga Tumoral
6.
Public Health ; 155: 62-68, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29306625

RESUMEN

OBJECTIVES: This study investigates morbidity and mortality suffered by divers in the USA and Canada. STUDY DESIGN: Prospectively recruited probability-weighted sample for estimating the national burden of injury and a weighted retrospective survey for estimating exposure. METHODS: The National Electronic Surveillance System and Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) were searched for scuba diving injuries. The Divers Alert Network diving fatality database was searched for deaths, and Sports and Fitness Industry Association estimates for diving were obtained from annual surveys. RESULTS: In the USA, there were an estimated 1394 emergency department (ED) presentations annually for scuba-related injuries. The majority (80%) were treated and/or released. There were an estimated 306 million dives made by the US residents 2006-2015 and concurrently 563 recreational diving deaths, a fatality rate of 0.18 per 105 dives and 1.8 per 105 diver-years. There were 658 diving deaths in the US 2006-2015 and 13,943 ED presentations for scuba injuries, giving a ratio of 47 diving deaths in the USA for every 1000 ED presentations. There were 98 cases of scuba-related injuries identified in the CHIRPP data. The prevalence of scuba-related injuries for patients aged 3-17 years was 1.5 per 105 cases, and the prevalence of scuba-related injuries to patients 18-62 years was 16.5 per 105 cases. DISCUSSION: In Canada and the USA, only one out of every 10,000 ED presentations is due to a scuba-related injury. That there are 47 deaths for every 1000 ED presentations for scuba injuries speaks to the relatively unforgiving environment in which scuba diving takes place. For 1.8 deaths per million recreational dives, mortality in scuba diving is nonetheless relatively low.


Asunto(s)
Buceo/lesiones , Recreación , Heridas y Lesiones/epidemiología , Adolescente , Adulto , Canadá/epidemiología , Niño , Preescolar , Bases de Datos Factuales , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Estados Unidos/epidemiología , Heridas y Lesiones/mortalidad , Adulto Joven
7.
Clin Exp Allergy ; 47(5): 693-703, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27770477

RESUMEN

BACKGROUND: Allergen-specific immunotherapy (AIT) with birch pollen generates Bet v 1-specific immunoglobulin (Ig)G4 which blocks IgE-mediated hypersensitivity mechanisms. Whether IgG4 specific for Bet v 1a competes with IgE for identical epitopes or whether novel epitope specificities of IgG4 antibodies are developed is under debate. OBJECTIVE: We sought to analyze the epitope specificities of IgE and IgG4 antibodies from sera of patients who received AIT. METHODS: 15 sera of patients (13/15 received AIT) with Bet v 1a-specific IgE and IgG4 were analyzed. The structural arrangements of recombinant (r)Bet v 1a and rBet v 1a_11x , modified in five potential epitopes, were analyzed by circular dichroism and nuclear magnetic resonance spectroscopy. IgE binding to Bet v 1 was assessed by ELISA and mediator release assays. Competitive binding of monoclonal antibodies specific for Bet v 1a and serum IgE/IgG4 to rBet v 1a and serum antibody binding to a non-allergenic Bet v 1-type model protein presenting an individual epitope for IgE was analyzed in ELISA and western blot. RESULTS: rBet v 1a_11x had a Bet v 1a - similar secondary and tertiary structure. Monomeric dispersion of rBet v 1a_11x was concentration and buffer-dependent. Up to 1500-fold increase in the EC50 for IgE-mediated mediator release induced by rBet v 1a_11x was determined. The reduction of IgE and IgG4 binding to rBet v 1a_11x was comparable in 67% (10/15) of sera. Bet v 1a-specific monoclonal antibodies inhibited binding of serum IgE and IgG4 to 66.1% and 64.9%, respectively. Serum IgE and IgG4 bound specifically to an individual epitope presented by our model protein in 33% (5/15) of sera. CONCLUSION AND CLINICAL RELEVANCE: Patients receiving AIT develop Bet v 1a-specific IgG4 which competes with IgE for partly identical or largely overlapping epitopes. The similarities of epitopes for IgE and IgG4 might stimulate the development of epitope-specific diagnostics and therapeutics.


Asunto(s)
Antígenos de Plantas/inmunología , Desensibilización Inmunológica , Epítopos/inmunología , Inmunoglobulina E , Inmunoglobulina G , Rinitis Alérgica Estacional , Animales , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Masculino , Ratones , Rinitis Alérgica Estacional/sangre , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica Estacional/terapia
8.
Clin Exp Allergy ; 46(11): 1484-1497, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27533495

RESUMEN

BACKGROUND: Birch pollen-related soya allergy is mediated by Gly m 4. Conformational IgE epitopes of Gly m 4 are unknown. OBJECTIVE: To identify the IgE epitope profile of Gly m 4 in subjects with birch pollen-related soya allergy utilizing an epitope library presented by Gly m 4-type model proteins. METHODS: Sera from patients with (n = 26) and without (n = 19) allergy to soya as determined by oral provocation tests were studied. Specific IgE (Bet v 1/Gly m 4) was determined by ImmunoCAP. A library of 59 non-allergenic Gly m 4-type model proteins harbouring individual and multiple putative epitopes for IgE was tested in IgE binding assays. Primary, secondary and tertiary protein structures were assessed by mass spectrometry, circular dichroism and nuclear magnetic resonance spectroscopy. RESULTS: All subjects were sensitized to Gly m 4 and Bet v 1. Allergen-specific serum IgE levels ranged from 0.94 to > 100 kUA /L. The avidities of serum IgE were 5.06 ng (allergic) and 1.8 ng (tolerant) as determined by EC50 for IgE binding to Gly m 4. 96% (46/48) of the protein variants bound IgE. Model proteins had Gly m 4-type conformation and individual IgE binding clustered in six major surface areas. Gly m 4-specific IgE binding could be inhibited to up to 80% by model proteins harbouring individual IgE binding sites in an epitope-wise equimolar fashion. Receiver operating curve analysis revealed an area under fitted curve of up to 0.88 for model proteins and 0.66 for Gly m 4. CONCLUSION AND CLINICAL RELEVANCE: Serum levels and avidity of Gly m 4-specific IgE do not correlate with clinical reactivity to soya. Six IgE-binding areas, represented by 23 amino acids, account for more than 80% of total IgE binding capacity of Gly m 4. Model proteins may be used for epitope-resolved diagnosis to differentiate birch-soya allergy from clinical tolerance.


Asunto(s)
Antígenos de Plantas/inmunología , Mapeo Epitopo , Epítopos de Linfocito B/química , Epítopos de Linfocito B/inmunología , Inmunoglobulina E/inmunología , Modelos Moleculares , Conformación Proteica , Secuencia de Aminoácidos , Especificidad de Anticuerpos/inmunología , Antígenos de Plantas/química , Antígenos de Plantas/genética , Betula/inmunología , Reacciones Cruzadas/inmunología , Mapeo Epitopo/métodos , Variación Genética , Humanos , Hipersensibilidad/inmunología , Tolerancia Inmunológica , Inmunoglobulina G/inmunología , Polen/inmunología , Unión Proteica/inmunología , Curva ROC , Proteínas Recombinantes
9.
Water Res ; 100: 126-136, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27183208

RESUMEN

Pharmaceuticals are designed to improve human and animal health, but may also be a threat to freshwater ecosystems, particularly after receiving urban or wastewater treatment plant (WWTP) effluents. Knowledge on the fate and attenuation of pharmaceuticals in engineered and natural ecosystems is rather fragmented, and comparable methods are needed to facilitate the comprehension of those processes amongst systems. In this study the dynamics of 8 pharmaceuticals (acetaminophen, sulfapyridine, sulfamethoxazole, carbamazepine, venlafaxine, ibuprofen, diclofenac, diazepam) and 11 of their transformation products were investigated in a WWTP and the associated receiving river ecosystem. During 3 days, concentrations of these compounds were quantified at the influents, effluents, and wastage of the WWTP, and at different distances downstream the effluent at the river. Attenuation (net balance between removal and release from and to the water column) was estimated in both engineered and natural systems using a comparable model-based approach by considering different uncertainty sources (e.g. chemical analysis, sampling, and flow measurements). Results showed that pharmaceuticals load reduction was higher in the WWTP, but attenuation efficiencies (as half-life times) were higher in the river. In particular, the load of only 5 out of the 19 pharmaceuticals was reduced by more than 90% at the WWTP, while the rest were only partially or non-attenuated (or released) and discharged into the receiving river. At the river, only the load of ibuprofen was reduced by more than 50% (out of the 6 parent compounds present in the river), while partial and non-attenuation (or release) was observed for some of their transformation products. Linkages in the routing of some pharmaceuticals (venlafaxine, carbamazepine, ibuprofen and diclofenac) and their corresponding transformation products were also identified at both WWTP and river. Finally, the followed procedure showed that dynamic attenuation in the coupled WWTP-river system could be successfully predicted with simple first order attenuation kinetics for most modeled compounds.


Asunto(s)
Ríos/química , Aguas Residuales/química , Animales , Ecosistema , Monitoreo del Ambiente , Humanos , Preparaciones Farmacéuticas , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua
12.
Allergy ; 68(11): 1377-86, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24053565

RESUMEN

BACKGROUND: IgE antibodies specific for the major birch pollen allergen frequently cross-react with Bet v 1 homologous food proteins, for example Cor a 1 in hazelnut and Mal d 1 in apple. Specific immunotherapy with birch pollen (BP-SIT) induces IgG4 antibodies that inhibit IgE binding to Bet v 1. However, information on cross-reactivity of BP-SIT-induced Bet v 1-specific IgG4 antibodies with food allergens is limited. In this study, we investigated the kinetics of production, cross-reactivity, and IgE-blocking activity of Bet v 1-specific IgG4 antibodies emerging during conventional BP-SIT and whether IgG4-epitopes overlapped with IgE epitopes. METHODS: IgE and IgG4 levels specific for Bet v 1, Mal d 1, and Cor a 1 were determined in 42 birch pollen-allergic patients before and during BP-SIT. Inhibition of IgE binding was studied by IgE-facilitated antigen-binding assays and basophil activation tests. Furthermore, inhibition of IgE-mediated activation of food allergen-reactive Bet v 1-specific T-cell lines was assessed. Competitive immunoscreening of phage-displayed peptides was applied to select mimotopes recognized by IgE and IgG4 antibodies, respectively. The resulting mimotopes were mapped on the surface of the 3D structure of the allergens using a computer-based algorithm. RESULTS: BP-SIT significantly increased Bet v 1- and food allergen-reactive IgG4 antibodies. In parallel, allergen-specific IgE levels decreased significantly. Sera containing food allergen-reactive IgG4 antibodies inhibited IgE binding, basophil activation, and IgE-mediated food allergen-induced T-cell proliferation. Predicted IgE and IgG4 epitopes on all allergens showed high overlap. CONCLUSION: Our results indicate that BP-SIT may induce Bet v 1-specific IgG4 antibodies that cross-react with related food allergens and inhibit IgE binding by epitope competition.


Asunto(s)
Alérgenos/inmunología , Especificidad de Anticuerpos/inmunología , Antígenos de Plantas/inmunología , Betula/inmunología , Desensibilización Inmunológica/métodos , Hipersensibilidad a los Alimentos/inmunología , Inmunoglobulina G/biosíntesis , Polen/inmunología , Adolescente , Adulto , Anticuerpos Bloqueadores/efectos de los fármacos , Antígenos de Plantas/administración & dosificación , Antígenos de Plantas/metabolismo , Línea Celular , Niño , Reacciones Cruzadas/inmunología , Humanos , Inmunoglobulina E/biosíntesis , Inmunoglobulina E/metabolismo , Inmunoglobulina G/metabolismo , Persona de Mediana Edad , Adulto Joven
14.
Phys Rev Lett ; 108(3): 035001, 2012 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-22400749

RESUMEN

Beam-driven plasma wakefield acceleration using low-ionization-threshold gas such as Li is combined with laser-controlled electron injection via ionization of high-ionization-threshold gas such as He. The He electrons are released with low transverse momentum in the focus of the copropagating, nonrelativistic-intensity laser pulse directly inside the accelerating or focusing phase of the Li blowout. This concept paves the way for the generation of sub-µm-size, ultralow-emittance, highly tunable electron bunches, thus enabling a flexible new class of an advanced free electron laser capable high-field accelerator.

17.
Ann Surg Oncol ; 15(3): 833-42, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18163174

RESUMEN

BACKGROUND: Lumpectomy followed by radiation is standard treatment for early breast cancer. Recently, the use of partial breast intraoperative radiation (IORT) has been developed, and patients selected for IORT should not have positive margins. This study's purpose was to identify factors predicting negative margins after lumpectomy. METHODS: Patient age, preoperative investigations, surgery, final pathology, and margin status were examined using a prospective database between 1999 and 2005. Univariate and multivariate logistic regression analysis were performed to identify patient and tumor factors predicting an increased rate of negative margins. The results were used to generate a patient selection algorithm. RESULTS: The rate of positive margins at first resection was 17% in 730 lumpectomies (708 patients). Multivariate analysis revealed that older age (P = .0006), smaller tumor size (P < .0025), type of surgery (OR = 3.4 for ultrasound vs mammogram-guided wire localization, P = .003), and having a core needle biopsy (CNB) with preoperative cancer diagnosis (P < .0001) were predictive for having a negative margin. Patients older than age 50 with a preoperative CNB showing invasive cancer less that 3 cm that can be localized under ultrasound had a negative margin rate of 98% (n = 178). These patients would be ideal for consideration of IORT. CONCLUSIONS: Negative margin rates after lumpectomy are predicted by age, tumor size, preoperative investigations, and localization technique. These variables can be used to select patients for IORT with a 2.2% chance of positive margins.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Mastectomía Segmentaria , Radioterapia Adyuvante , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/terapia , Carcinoma Ductal de Mama/terapia , Carcinoma Intraductal no Infiltrante/terapia , Bases de Datos como Asunto , Femenino , Humanos , Periodo Intraoperatorio , Persona de Mediana Edad , Estudios Prospectivos
20.
Oncogene ; 25(37): 5145-54, 2006 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-16636678

RESUMEN

We and others have demonstrated already that TRAIL (TNF-related apoptosis-inducing ligand) is a very promising candidate for molecular targeted anticancer therapy, especially when combined with ionizing radiation or other DNA-damaging agents. Agonist monoclonal antibodies that activate and are specific for the death signaling TRAIL receptors are an alternative method to stimulate the programmed cell death pathway. Phase 1 clinical trials have subsequently been conducted and shown a very good tolerability of these antibodies. In order to assess the efficacy of TRAIL receptor stimulation to induce cell death by this alternate method, we studied the combination of the agonistic-TRAIL receptor antibodies HGS-ETR1 and HGS-ETR2 with radiation in vitro and in vivo. Induction of apoptosis after combined treatment with TRAIL receptor antibodies HGS-ETR1 and/or HGS-ETR2 (0.01, 0.1, 1.0 mg/ml) and irradiation with 2, 5 or 10 Gy was determined by fluorescence microscopy and Western blot analysis of caspase-8 and PARP. The colorectal tumour cell lines Colo 205, HCT 116 and HCT-15 were used for in vitro experiments. Growth delay experiments were performed with combined treatment with fractionated irradiation (days 1-5 and 3 Gy single dose/day) and the receptor antibodies (intraperitonially, three different concentrations, application on days 1, 4 and 8) on Colo 205 xenograft-bearing NMRI (nu/nu) nude mice. HGS-ETR1 and HGS-ETR2 induced apoptotic cell death in a dose-dependent fashion and significantly increased cell death in combination with irradiation in vitro when compared to either irradiation or antibody treatment alone. The efficacy of the combined treatment seems to be at least partially Bax-dependent. Similar to the results from cell culture experiments, in vivo experiments demonstrated a dose-dependent delay in tumour growth after combined treatment. In vivo, in the Colo205 xenograft model, HGS-ETR2 revealed a higher activity than HGS-ETR1. This is the first study to demonstrate significant efficacy of combined treatment with the monoclonal agonistic TRAIL receptor antibodies HGS-ETR1 and HGS-ETR2 and ionising radiation in in vitro and in vivo models. We postulate that HGS-ETR1 and HGS-ETR2 will be very promising new agents in the field of molecular targeted multi-modality anticancer therapy.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Proteínas Reguladoras de la Apoptosis/inmunología , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/radioterapia , Glicoproteínas de Membrana/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Anticuerpos Monoclonales/uso terapéutico , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/uso terapéutico , División Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Humanos , Cinética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/uso terapéutico , Ligando Inductor de Apoptosis Relacionado con TNF , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/uso terapéutico
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