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1.
BMC Med Inform Decis Mak ; 22(1): 112, 2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35477495

RESUMEN

BACKGROUND: Wearables, as small portable computer systems worn on the body, can track user fitness and health data, which can be used to customize health insurance contributions individually. In particular, insured individuals with a healthy lifestyle can receive a reduction of their contributions to be paid. However, this potential is hardly used in practice. OBJECTIVE: This study aims to identify which barrier factors impede the usage of wearables for assessing individual risk scores for health insurances, despite its technological feasibility, and to rank these barriers according to their relevance. METHODS: To reach these goals, we conduct a ranking-type Delphi study with the following three stages. First, we collected possible barrier factors from a panel of 16 experts and consolidated them to a list of 11 barrier categories. Second, the panel was asked to rank them regarding their relevance. Third, to enhance the panel consensus, the ranking was revealed to the experts, who were then asked to re-rank the barriers. RESULTS: The results suggest that regulation is the most important barrier. Other relevant barriers are false or inaccurate measurements and application errors caused by the users. Additionally, insurers could lack the required technological competence to use the wearable data appropriately. CONCLUSION: A wider use of wearables and health apps could be achieved through regulatory modifications, especially regarding privacy issues. Even after assuring stricter regulations, users' privacy concerns could partly remain, if the data exchange between wearables manufacturers, health app providers, and health insurers does not become more transparent.


Asunto(s)
Seguro de Salud , Dispositivos Electrónicos Vestibles , Ejercicio Físico , Humanos , Privacidad
2.
Wiley Interdiscip Rev RNA ; : e1724, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35298877

RESUMEN

The RNA-binding protein Quaking (QKI) has emerged as a potent regulator of cellular differentiation in developmental and pathological processes. The QKI gene is itself alternatively spliced to produce three major isoforms, QKI-5, QKI-6, and QKI-7, that possess very distinct functions. Here, we highlight roles of the different QKI isoforms in neuronal, vascular, muscle, and monocyte cell differentiation, and during epithelial-mesenchymal transition in cancer progression. QKI isoforms control cell differentiation through regulating alternative splicing, mRNA stability and translation, with activities in gene transcription now also becoming evident. These diverse functions of the QKI isoforms contribute to their broad influences on RNA metabolism and cellular differentiation. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Processing > Splicing Regulation/Alternative Splicing RNA in Disease and Development > RNA in Development.

3.
EClinicalMedicine ; 38: 101028, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34308321

RESUMEN

BACKGROUND: The negative impact of continued school closures during the height of the COVID-19 pandemic warrants the establishment of cost-effective strategies for surveillance and screening to safely reopen and monitor for potential in-school transmission. Here, we present a novel approach to increase the availability of repetitive and routine COVID-19 testing that may ultimately reduce the overall viral burden in the community. METHODS: We implemented a testing program using the SalivaClear࣪ pooled surveillance method that included students, faculty and staff from K-12 schools (student age range 5-18 years) and universities (student age range >18 years) across the country (Mirimus Clinical Labs, Brooklyn, NY). The data analysis was performed using descriptive statistics, kappa agreement, and outlier detection analysis. FINDINGS: From August 27, 2020 until January 13, 2021, 253,406 saliva specimens were self-collected from students, faculty and staff from 93 K-12 schools and 18 universities. Pool sizes of up to 24 samples were tested over a 20-week period. Pooled testing did not significantly alter the sensitivity of the molecular assay in terms of both qualitative (100% detection rate on both pooled and individual samples) and quantitative (comparable cycle threshold (Ct) values between pooled and individual samples) measures. The detection of SARS-CoV-2 in saliva was comparable to the nasopharyngeal swab. Pooling samples substantially reduced the costs associated with PCR testing and allowed schools to rapidly assess transmission and adjust prevention protocols as necessary. In one instance, in-school transmission of the virus was determined within the main office and led to review and revision of heating, ventilating and air-conditioning systems. INTERPRETATION: By establishing low-cost, weekly testing of students and faculty, pooled saliva analysis for the presence of SARS-CoV-2 enabled schools to determine whether transmission had occurred, make data-driven decisions, and adjust safety protocols. We provide strong evidence that pooled testing may be a fundamental component to the reopening of schools by minimizing the risk of in-school transmission among students and faculty. FUNDING: Skoll Foundation generously provided funding to Mobilizing Foundation and Mirimus for these studies.

4.
Acta Neuropathol Commun ; 8(1): 194, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33203474

RESUMEN

Sanfilippo syndrome is an untreatable form of childhood-onset dementia. Whilst several therapeutic strategies are being evaluated in human clinical trials including i.v. delivery of AAV9-based gene therapy, an urgent unmet need is the availability of non-invasive, quantitative measures of neurodegeneration. We hypothesise that as part of the central nervous system, the retina may provide a window through which to 'visualise' degenerative lesions in brain and amelioration of them following treatment. This is reliant on the age of onset and the rate of disease progression being equivalent in retina and brain. For the first time we have assessed in parallel, the nature, age of onset and rate of retinal and brain degeneration in a mouse model of Sanfilippo syndrome. Significant accumulation of heparan sulphate and expansion of the endo/lysosomal system was observed in both retina and brain pre-symptomatically (by 3 weeks of age). Robust and early activation of micro- and macroglia was also observed in both tissues. There was substantial thinning of retina and loss of rod and cone photoreceptors by ~ 12 weeks of age, a time at which cognitive symptoms are noted. Intravenous delivery of a clinically relevant AAV9-human sulphamidase vector to neonatal mice prevented disease lesion appearance in retina and most areas of brain when assessed 6 weeks later. Collectively, the findings highlight the previously unrecognised early and significant involvement of retina in the Sanfilippo disease process, lesions that are preventable by neonatal treatment with AAV9-sulphamidase. Critically, our data demonstrate for the first time that the advancement of retinal disease parallels that occurring in brain in Sanfilippo syndrome, thus retina may provide an easily accessible neural tissue via which brain disease development and its amelioration with treatment can be monitored.


Asunto(s)
Encéfalo/patología , Mucopolisacaridosis III/patología , Enfermedades Neurodegenerativas/patología , Retina/patología , Degeneración Retiniana/patología , Animales , Enfermedades Asintomáticas , Modelos Animales de Enfermedad , Endosomas/patología , Terapia Genética , Heparitina Sulfato/metabolismo , Humanos , Hidrolasas/genética , Lisosomas/patología , Ratones , Microglía/patología , Mucopolisacaridosis III/genética , Mucopolisacaridosis III/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Células Fotorreceptoras Retinianas Conos/patología , Degeneración Retiniana/metabolismo , Células Fotorreceptoras Retinianas Bastones/patología
5.
J Neuropathol Exp Neurol ; 79(10): 1084-1092, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32743645

RESUMEN

We created an excitotoxic striatal lesion model of Huntington disease (HD) in sheep, using the N-methyl-d-aspartate receptor agonist, quinolinic acid (QA). Sixteen sheep received a bolus infusion of QA (75 µL, 180 mM) or saline, first into the left and then (4 weeks later) into the right striatum. Magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI) of the striata were performed. Metabolite concentrations and fractional anisotropy (FA) were measured at baseline, acutely (1 week after each surgery) and chronically (5 weeks or greater after the surgeries). There was a significant decrease in the neuronal marker N-acetylaspartate (NAA) and in FA in acutely lesioned striata of the QA-lesioned sheep, followed by a recovery of NAA and FA in the chronically lesioned striata. NAA level changes indicate acute death and/or impairment of neurons immediately after surgery, with recovery of reversibly impaired neurons over time. The change in FA values of the QA-lesioned striata is consistent with acute structural disruption, followed by re-organization and glial cell infiltration with time. Our study demonstrates that MRS and DTI changes in QA-sheep are consistent with HD-like pathology shown in other model species and that the MR investigations can be performed in sheep using a clinically relevant human 3T MRI scanner.


Asunto(s)
Modelos Animales de Enfermedad , Enfermedad de Huntington/inducido químicamente , Enfermedad de Huntington/metabolismo , Enfermedad de Huntington/patología , Ácido Quinolínico/toxicidad , Animales , Anisotropía , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/patología , Imagen de Difusión Tensora/métodos , Espectroscopía de Resonancia Magnética/métodos , Masculino , Ovinos , Oveja Doméstica
6.
Mol Ther Methods Clin Dev ; 17: 174-187, 2020 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-31909089

RESUMEN

Patients with mucopolysaccharidosis type IIIA (MPS IIIA) lack the lysosomal enzyme sulfamidase (SGSH), which is responsible for the degradation of heparan sulfate (HS). Build-up of undegraded HS results in severe progressive neurodegeneration for which there is currently no treatment. The ability of the vector adeno-associated virus (AAV)rh.10-CAG-SGSH (LYS-SAF302) to correct disease pathology was evaluated in a mouse model for MPS IIIA. LYS-SAF302 was administered to 5-week-old MPS IIIA mice at three different doses (8.6E+08, 4.1E+10, and 9.0E+10 vector genomes [vg]/animal) injected into the caudate putamen/striatum and thalamus. LYS-SAF302 was able to dose-dependently correct or significantly reduce HS storage, secondary accumulation of GM2 and GM3 gangliosides, ubiquitin-reactive axonal spheroid lesions, lysosomal expansion, and neuroinflammation at 12 weeks and 25 weeks post-dosing. To study SGSH distribution in the brain of large animals, LYS-SAF302 was injected into the subcortical white matter of dogs (1.0E+12 or 2.0E+12 vg/animal) and cynomolgus monkeys (7.2E+11 vg/animal). Increases of SGSH enzyme activity of at least 20% above endogenous levels were detected in 78% (dogs 4 weeks after injection) and 97% (monkeys 6 weeks after injection) of the total brain volume. Taken together, these data validate intraparenchymal AAV administration as a promising method to achieve widespread enzyme distribution and correction of disease pathology in MPS IIIA.

7.
EMBO J ; 37(13)2018 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-29871889

RESUMEN

Members of the miR-200 family are critical gatekeepers of the epithelial state, restraining expression of pro-mesenchymal genes that drive epithelial-mesenchymal transition (EMT) and contribute to metastatic cancer progression. Here, we show that miR-200c and another epithelial-enriched miRNA, miR-375, exert widespread control of alternative splicing in cancer cells by suppressing the RNA-binding protein Quaking (QKI). During EMT, QKI-5 directly binds to and regulates hundreds of alternative splicing targets and exerts pleiotropic effects, such as increasing cell migration and invasion and restraining tumour growth, without appreciably affecting mRNA levels. QKI-5 is both necessary and sufficient to direct EMT-associated alternative splicing changes, and this splicing signature is broadly conserved across many epithelial-derived cancer types. Importantly, several actin cytoskeleton-associated genes are directly targeted by both QKI and miR-200c, revealing coordinated control of alternative splicing and mRNA abundance during EMT These findings demonstrate the existence of a miR-200/miR-375/QKI axis that impacts cancer-associated epithelial cell plasticity through widespread control of alternative splicing.


Asunto(s)
Empalme Alternativo/fisiología , Plasticidad de la Célula/fisiología , Transición Epitelial-Mesenquimal/fisiología , MicroARNs/fisiología , Proteínas de Unión al ARN/fisiología , Animales , Línea Celular Tumoral , Movimiento Celular , Perros , Humanos , Células de Riñón Canino Madin Darby , Ratones SCID
8.
J Air Waste Manag Assoc ; 68(8): 763-800, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29364776

RESUMEN

Poor air quality is still a threat for human health in many parts of the world. In order to assess measures for emission reductions and improved air quality, three-dimensional atmospheric chemistry transport modeling systems are used in numerous research institutions and public authorities. These models need accurate emission data in appropriate spatial and temporal resolution as input. This paper reviews the most widely used emission inventories on global and regional scales and looks into the methods used to make the inventory data model ready. Shortcomings of using standard temporal profiles for each emission sector are discussed, and new methods to improve the spatiotemporal distribution of the emissions are presented. These methods are often neither top-down nor bottom-up approaches but can be seen as hybrid methods that use detailed information about the emission process to derive spatially varying temporal emission profiles. These profiles are subsequently used to distribute bulk emissions such as national totals on appropriate grids. The wide area of natural emissions is also summarized, and the calculation methods are described. Almost all types of natural emissions depend on meteorological information, which is why they are highly variable in time and space and frequently calculated within the chemistry transport models themselves. The paper closes with an outlook for new ways to improve model ready emission data, for example, by using external databases about road traffic flow or satellite data to determine actual land use or leaf area. In a world where emission patterns change rapidly, it seems appropriate to use new types of statistical and observational data to create detailed emission data sets and keep emission inventories up-to-date. IMPLICATIONS: Emission data are probably the most important input for chemistry transport model (CTM) systems. They need to be provided in high spatial and temporal resolution and on a grid that is in agreement with the CTM grid. Simple methods to distribute the emissions in time and space need to be replaced by sophisticated emission models in order to improve the CTM results. New methods, e.g., for ammonia emissions, provide grid cell-dependent temporal profiles. In the future, large data fields from traffic observations or satellite observations could be used for more detailed emission data.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Modelos Teóricos , Contaminantes Atmosféricos/química , Humanos
9.
Semin Cell Dev Biol ; 75: 50-60, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28789987

RESUMEN

Interconversions between epithelial and mesenchymal states, often referred to as epithelial mesenchymal transition (EMT) and its reverse MET, play important roles in embryonic development and are recapitulated in various adult pathologies including cancer progression. These conversions are regulated by complex transcriptional and post-transcriptional mechanisms including programs of alternative splicing which are orchestrated by specific splicing factors. This review will focus on the latest developments in our understanding of the splicing factors regulating epithelial mesenchymal plasticity associated with cancer progression and the induction of pluripotency, including potential roles for circular RNAs (circRNAs) which have been recently implicated in these processes.


Asunto(s)
Empalme Alternativo , Transición Epitelial-Mesenquimal/genética , Regulación de la Expresión Génica , ARN/genética , Animales , Humanos , Modelos Genéticos , Isoformas de ARN/genética , Precursores del ARN/genética , Precursores del ARN/metabolismo , ARN Circular , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
10.
EMBO J ; 35(4): 402-13, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26783364

RESUMEN

The Bcl-2 family proteins Bax and Bak are essential for the execution of many apoptotic programs. During apoptosis, Bax translocates to the mitochondria and mediates the permeabilization of the outer membrane, thereby facilitating the release of pro-apoptotic proteins. Yet the mechanistic details of the Bax-induced membrane permeabilization have so far remained elusive. Here, we demonstrate that activated Bax molecules, besides forming large and compact clusters, also assemble, potentially with other proteins including Bak, into ring-like structures in the mitochondrial outer membrane. STED nanoscopy indicates that the area enclosed by a Bax ring is devoid of mitochondrial outer membrane proteins such as Tom20, Tom22, and Sam50. This strongly supports the view that the Bax rings surround an opening required for mitochondrial outer membrane permeabilization (MOMP). Even though these Bax assemblies may be necessary for MOMP, we demonstrate that at least in Drp1 knockdown cells, these assemblies are not sufficient for full cytochrome c release. Together, our super-resolution data provide direct evidence in support of large Bax-delineated pores in the mitochondrial outer membrane as being crucial for Bax-mediated MOMP in cells.


Asunto(s)
Apoptosis , Mitocondrias/enzimología , Membranas Mitocondriales/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Multimerización de Proteína , Proteína X Asociada a bcl-2/metabolismo , Línea Celular , Citocromos c/metabolismo , Humanos , Microscopía Fluorescente , Mitocondrias/fisiología , Membranas Mitocondriales/fisiología , Permeabilidad
11.
Laryngoscope ; 126(7): E255-60, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26403138

RESUMEN

OBJECTIVES/HYPOTHESIS: To assess the safety and feasibility of using ß-tricalcium phosphate grafts in airway reconstruction in rabbits. STUDY DESIGN: Interventional animal study. METHODS: Ten New Zealand White rabbits underwent division of the anterior cricoid cartilage with interposition of a graft sculpted from ß-tricalcium phosphate blocks. Grafts were secured with sutures or were self-retaining. Rabbit larynges were harvested according to the following schedule: one at 1 week, one at 3 months, and two each at 2 weeks, 4 weeks, 6 months, and 1 year after graft implantation. Specimens were evaluated grossly for overall graft incorporation. Sections through the graft substance were prepared for histology. All sections were reviewed by a pathologist for evidence of vascular ingrowth, granulation tissue, inflammation, epithelialization, and graft resorption. RESULTS: There were no major postoperative complications. Gross examination revealed persistent widening of the airway at the level of graft placement. Histologic evaluation of the larynges showed growth of new blood vessels within all specimens and absence of significant granulation tissue near the airway lumen. The graft was at least partially covered by an epithelium in seven of the 10 specimens. Evidence of graft resorption was present as early as 4 weeks after implantation, with replacement of the graft substance by fibrous tissue, fatty tissue, bone, or cartilage. CONCLUSIONS: ß-tricalcium phosphate grafts can be used safely in airway reconstruction procedures in rabbits. Further research is necessary to demonstrate its safety in human airway reconstruction in addition to further clarifying the processes of graft resorption and integration. LEVEL OF EVIDENCE: NA Laryngoscope, 126:E255-E260, 2016.


Asunto(s)
Manejo de la Vía Aérea/instrumentación , Fosfatos de Calcio , Implantes Experimentales , Procedimientos Quirúrgicos Reconstructivos/instrumentación , Manejo de la Vía Aérea/métodos , Animales , Cartílago Cricoides/cirugía , Estudios de Factibilidad , Laringe/cirugía , Masculino , Proyectos Piloto , Conejos , Procedimientos Quirúrgicos Reconstructivos/métodos , Resultado del Tratamiento
12.
Arch Toxicol ; 90(11): 2745-2761, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26525392

RESUMEN

Predictive test systems to assess the mode of action of chemical carcinogens are urgently required. Within the present study, we applied the Fluidigm dynamic array on the BioMark™ HD System for quantitative high-throughput RT-qPCR analysis of 95 genes and 96 samples in parallel, selecting genes crucial for maintaining genomic stability, including stress response as well as DNA repair, cell cycle control, apoptosis and mitotic signaling. The specificity of each individually designed sequence-specific primer pair and their respective target amplicons were evaluated via melting curve analysis as part of qPCR and size verification via agarose gel electrophoresis. For each gene, calibration curves displayed high efficiencies and correlation coefficients in the identified linear dynamic range as well as low intra-assay variations. Data were processed via Fluidigm real-time PCR analysis and GenEx software, and results were depicted as relative gene expression according to the ΔΔC q method. Subsequently, gene expression analyses were conducted in cadmium-treated adenocarcinoma A549 and epithelial bronchial BEAS-2B cells. They revealed distinct dose- and time-dependent and also cell-type-specific gene expression patterns, including the induction of genes coding for metallothioneins, the oxidative stress response, cell cycle control, mitotic signaling and apoptosis. Interestingly, while genes coding for the DNA damage response were induced, distinct DNA repair genes were down-regulated at the transcriptional level. Thus, this approach provided a comprehensive overview on the interaction by cadmium with distinct signaling pathways, also reflecting molecular modes of action in cadmium-induced carcinogenicity. Therefore, the test system appears to be a promising tool for toxicological risk assessment.


Asunto(s)
Adenocarcinoma Bronquioloalveolar/inducido químicamente , Cadmio/toxicidad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Inestabilidad Genómica/efectos de los fármacos , Neoplasias Pulmonares/inducido químicamente , Mutágenos/toxicidad , Mucosa Respiratoria/efectos de los fármacos , Células A549 , Adenocarcinoma Bronquioloalveolar/metabolismo , Adenocarcinoma Bronquioloalveolar/patología , Proteínas Reguladoras de la Apoptosis/agonistas , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Calibración , Línea Celular , Perfilación de la Expresión Génica , Ensayos Analíticos de Alto Rendimiento , Humanos , Cinética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
Magn Reson Med ; 75(3): 1086-99, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25845973

RESUMEN

PURPOSE: Phase-constrained parallel MRI approaches have the potential for significantly improving the image quality of accelerated MRI scans. The purpose of this study was to investigate the properties of two different phase-constrained parallel MRI formulations, namely the standard phase-constrained approach and the virtual conjugate coil (VCC) concept utilizing conjugate k-space symmetry. METHODS: Both formulations were combined with image-domain algorithms (SENSE) and a mathematical analysis was performed. Furthermore, the VCC concept was combined with k-space algorithms (GRAPPA and ESPIRiT) for image reconstruction. In vivo experiments were conducted to illustrate analogies and differences between the individual methods. Furthermore, a simple method of improving the signal-to-noise ratio by modifying the sampling scheme was implemented. RESULTS: For SENSE, the VCC concept was mathematically equivalent to the standard phase-constrained formulation and therefore yielded identical results. In conjunction with k-space algorithms, the VCC concept provided more robust results when only a limited amount of calibration data were available. Additionally, VCC-GRAPPA reconstructed images provided spatial phase information with full resolution. CONCLUSIONS: Although both phase-constrained parallel MRI formulations are very similar conceptually, there exist important differences between image-domain and k-space domain reconstructions regarding the calibration robustness and the availability of high-resolution phase information.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Procesamiento de Señales Asistido por Computador , Imagen por Resonancia Magnética/instrumentación
14.
J Am Coll Radiol ; 12(8): 876-83, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26123738

RESUMEN

PURPOSE: Training in cardiovascular MR (CMR) is an important topic in times of growing acceptance of the method for accurate diagnosis and management of cardiovascular disease. However, off-site training is becoming less acceptable with increasing cost and time pressures. We introduce a novel CMR network, capable of providing, remotely, part of CMR training and continuous expert support. By providing a technical and operational blueprint, we want to share our experience in building teaching networks. METHODS: Conceptual, technical, and content-related characteristics of our teaching methods are introduced. A total of 97 participants in traditional fellowship CMR teaching and novel module-based network teaching were surveyed to assess their CMR performance. RESULTS: The number of hospitals in our CMR network increased from five in 2009 to 14 in 2014. A total of 79% of network hospitals conducted >100 CMR scans annually. Among these network hospitals are four small institutions (<400 beds), and five medium-sized hospitals (400-1,000 beds). Network teaching reduced off-site training to only five weeks. The time to the first independently conducted CMR scans was one week, with network teaching, but >1 month for 32% of participants in traditional CMR teaching. The CMR network enables experts from distant locations to supervise and control CMR scans in a distant hospital, in real time. CONCLUSIONS: CMR networks provide an efficient teaching platform with a minimum of off-site time for trainees. Real-time remote supervision and scan control capabilities support the decentralization of CMR expertise and enables even small and rurally located institutions to offer high-quality CMR scans.


Asunto(s)
Cardiología/educación , Enfermedades Cardiovasculares/diagnóstico , Instrucción por Computador/métodos , Internet/organización & administración , Imagen por Resonancia Cinemagnética , Radiología/educación , Curriculum , Alemania , Estudios Multicéntricos como Asunto , Proyectos Piloto
15.
Ann Otol Rhinol Laryngol ; 124(10): 803-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25944597

RESUMEN

OBJECTIVE: While generally well tolerated for the treatment of severe laryngomalacia, bilateral supraglottoplasty has potential complications including supraglottic stenosis and aspiration. We report a more conservative staged supraglottoplasty in infants with severe laryngomalacia. METHODS: A retrospective review was performed of our patients who underwent staged supraglottoplasty from June 2007 to June 2012. Fifteen infants were identified and scored based on stridor, retractions, oxygen saturation, and feeding quality. Outcomes were compared with those reported in the literature for conventional bilateral supraglottoplasty. RESULTS: Seventy-three percent had significant improvement or resolution of stridor following the first stage of surgery and 100% in those undergoing a second stage. Twelve patients (80%) had mild to no retractions following one procedure and 100% had resolution after a second surgery. All 6 patients with recurrent preoperative desaturations had resolution after the first stage of surgery. Of the 11 infants who had preoperative moderate-severe feeding problems, 9 of them (82%) had resolution after one surgery and the remaining 2 had resolution after a second surgery. There were no complications in any of the patients. CONCLUSIONS: Staged supraglottoplasty appears to be an effective, low-risk method to treat severe laryngomalacia. A second procedure was only required in 40% of patients.


Asunto(s)
Laringomalacia , Laringoplastia , Epiglotis/patología , Epiglotis/cirugía , Métodos de Alimentación , Femenino , Glotis/patología , Glotis/cirugía , Humanos , Lactante , Laringomalacia/complicaciones , Laringomalacia/congénito , Laringomalacia/metabolismo , Laringomalacia/fisiopatología , Laringomalacia/cirugía , Laringoplastia/efectos adversos , Laringoplastia/métodos , Masculino , Consumo de Oxígeno , Periodo Posoperatorio , Ruidos Respiratorios/etiología , Ruidos Respiratorios/fisiopatología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
16.
Mar Pollut Bull ; 86(1-2): 219-228, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-25125287

RESUMEN

The drift of marine litter in the southern North Sea was simulated with the offline Lagrangian transport model PELETS-2D. Assuming different source regions, passive tracer particles were released every 28 h within a nine-year period. Based on pre-calculated hourly wind and ocean current data, drift simulations were carried out forward and backward in time with and without the assumption of extra wind forces influencing particle movement. Due to strong variability of currents, backward simulations did not allow for the identification of particular source regions influencing given monitoring sites. Neither accumulation regions at open sea could be identified by forward simulations. A seasonal signal, however, could be identified in the number of tracer particles that reached the coastal areas. Both particle drift velocity and variability of drift paths further increased when an extra wind drift was assumed.


Asunto(s)
Monitoreo del Ambiente/métodos , Modelos Teóricos , Residuos Sólidos/estadística & datos numéricos , Movimientos del Agua , Viento , Simulación por Computador , Mar del Norte
17.
Zoo Biol ; 33(3): 234-44, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24752991

RESUMEN

The Spix's macaw (Cyanopsitta spixii) is the rarest parrot on earth. The remaining captive population consists of 79 individuals. Captive propagation is ongoing to increase the number of individuals for future reintroduction back into the wild. Unfortunately, from 2004 to 2012, only 33 chicks hatched from 331 eggs. Semen evaluation and assisted reproduction might help to overcome this problem. Therefore, a recently developed electro-stimulated semen collection technique was used in Spix's macaws. Semen collection was successful in 39 of 78 attempts in 10 out of 17 males. Examination of the semen included evaluation of volume, color, consistency, contaminations and pH, as well as determination of motility, viability, morphology, concentration, and total count of spermatozoa. The median volume of semen samples was 5.6 µl. On average, 34.7 ± 21.9% (median 30%) of the sperm were motile and 23.1 ± 22.1% (median 16.5%) were progressively motile. In addition to spermatozoa, round cells were detected in the samples. Median sperm concentration was 15,500/µl (range 500-97,500/µl) and median viability was 50% (range 5-87%). Morphological examination revealed in 26.5% normal spermatozoa, high numbers of malformations of the head (50.2%) and tail region (20.5%), with 29% of all sperm showing multiple abnormalities. Artificial insemination was performed in three females; two eggs laid after artificial insemination had spermatozoa present on the perivitelline layer, suggesting the possible success of the insemination technique. Although no fertilization could be demonstrated, these preliminary results are promising, as they indicate that assisted reproduction might be a tool for species conservation in the Spix's macaw.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Inseminación Artificial/veterinaria , Loros/fisiología , Análisis de Semen/veterinaria , Animales , Femenino , Masculino , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/anomalías , Espermatozoides/citología
18.
MAGMA ; 27(6): 567-77, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24643838

RESUMEN

OBJECTIVE: The quantification of magnetic resonance relaxation parameters T 1 and T 2 have the potential for improved disease detection and classification over standard clinical weighted imaging. Performing a mono-exponential fit on multi spin-echo (MSE) data provides quantitative T 2 values in a clinically acceptable scan-time. However, due to technical imperfections of refocusing pulses, stimulated echo contributions to the signals lead to significant deviations in the resulting T 2 values. In this work, a simple auto-calibrating correction procedure is presented, allowing the accurate estimation of T 2 from MSE acquisitions. MATERIALS AND METHODS: Correction factors for T 2 values obtained from MSE acquisitions with a mono-exponential fit are derived from simulations following the extended phase graph formulation. A closed formula is given for the calculation of the required correction factors directly from the measured data itself. RESULTS: Simulations and phantom experiments show high accuracy of corrected T 2 values for a wide range of clinically relevant T 2 values and for different nominal refocusing flip angles. In addition, corrected T 2 maps of the human brain are presented. CONCLUSION: A simple recipe is provided to correct T 2 values obtained from MSE acquisitions via a mono-exponential fit for the influence of stimulated echoes. Since all required parameters are extracted from the data themselves, no additional acquisitions are required.


Asunto(s)
Algoritmos , Artefactos , Encéfalo/anatomía & histología , Imagen Eco-Planar/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Señales Asistido por Computador , Imagen Eco-Planar/instrumentación , Humanos , Análisis Numérico Asistido por Computador , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Magn Reson Med ; 72(6): 1680-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24436227

RESUMEN

PURPOSE: Cartesian turbo spin-echo (TSE) and radial TSE images are usually reconstructed by assembling data containing different contrast information into a single k-space. This approach results in mixed contrast contributions in the images, which may reduce their diagnostic value. The goal of this work is to improve the image contrast from radial TSE acquisitions by reducing the contribution of signals with undesired contrast information. METHODS: Radial TSE acquisitions allow the reconstruction of multiple images with different T2 contrasts using the k-space weighted image contrast (KWIC) filter. In this work, the image contrast is improved by reducing the band-width of the KWIC filter. Data for the reconstruction of a single image are selected from within a small temporal range around the desired echo time. The resulting dataset is undersampled and, therefore, an iterative parallel imaging algorithm is applied to remove aliasing artifacts. RESULTS: Radial TSE images of the human brain reconstructed with the proposed method show an improved contrast when compared with Cartesian TSE images or radial TSE images with conventional KWIC reconstructions. CONCLUSION: The proposed method provides multi-contrast images from radial TSE data with contrasts similar to multi spin-echo images. Contaminations from unwanted contrast weightings are strongly reduced.


Asunto(s)
Algoritmos , Artefactos , Encéfalo/anatomía & histología , Imagen Eco-Planar/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Técnica de Sustracción , Humanos , Movimiento (Física) , Reproducibilidad de los Resultados , Tamaño de la Muestra , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador , Marcadores de Spin
20.
J Arthroplasty ; 29(4): 831-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24099841

RESUMEN

This study compared the corrosion behavior of tantalum-coated cobalt-chromium modular necks with that of titanium alloy modular necks at their junction to titanium-alloy femoral stem. Tests were performed in a dry assembly and two wet assemblies, one contaminated with calf serum and the other contaminated with calf serum and bone particles. Whereas the titanium modular neck tested in the dry assembly showed no signs of corrosion, the titanium modular necks tested in both wet assemblies showed marked depositions and corrosive attacks. By contrast, the tantalum-coated cobalt-chromium modular necks showed no traces of corrosion or chemical attack in any of the three assemblies. This study confirms the protective effect of tantalum coating the taper region of cobalt-chromium modular neck components, suggesting that the use of tantalum may reduce the risk of implant failure due to corrosion.


Asunto(s)
Prótesis de Cadera , Diseño de Prótesis , Falla de Prótesis , Artroplastia de Reemplazo de Cadera , Materiales Biocompatibles , Fenómenos Biomecánicos , Aleaciones de Cromo , Corrosión , Estrés Mecánico , Tantalio , Titanio
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