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The Neuroscience Monoclonal Antibody Sequencing Initiative (NeuroMabSeq) is a concerted effort to determine and make publicly available hybridoma-derived sequences of monoclonal antibodies (mAbs) valuable to neuroscience research. Over 30 years of research and development efforts including those at the UC Davis/NIH NeuroMab Facility have resulted in the generation of a large collection of mouse mAbs validated for neuroscience research. To enhance dissemination and increase the utility of this valuable resource, we applied a high-throughput DNA sequencing approach to determine immunoglobulin heavy and light chain variable domain sequences from source hybridoma cells. The resultant set of sequences was made publicly available as a searchable DNA sequence database (neuromabseq.ucdavis.edu) for sharing, analysis and use in downstream applications. We enhanced the utility, transparency, and reproducibility of the existing mAb collection by using these sequences to develop recombinant mAbs. This enabled their subsequent engineering into alternate forms with distinct utility, including alternate modes of detection in multiplexed labeling, and as miniaturized single chain variable fragments or scFvs. The NeuroMabSeq website and database and the corresponding recombinant antibody collection together serve as a public DNA sequence repository of mouse mAb heavy and light chain variable domain sequences and as an open resource for enhancing dissemination and utility of this valuable collection of validated mAbs.
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Anticuerpos Monoclonales , Inmunosupresores , Animales , Ratones , Anticuerpos Monoclonales/genética , Hibridomas , Reproducibilidad de los Resultados , Bases de Datos de Ácidos NucleicosRESUMEN
The Neuroscience Monoclonal Antibody Sequencing Initiative (NeuroMabSeq) is a concerted effort to determine and make publicly available hybridoma-derived sequences of monoclonal antibodies (mAbs) valuable to neuroscience research. Over 30 years of research and development efforts including those at the UC Davis/NIH NeuroMab Facility have resulted in the generation of a large collection of mouse mAbs validated for neuroscience research. To enhance dissemination and increase the utility of this valuable resource, we applied a high-throughput DNA sequencing approach to determine immunoglobulin heavy and light chain variable domain sequences from source hybridoma cells. The resultant set of sequences was made publicly available as searchable DNA sequence database ( neuromabseq.ucdavis.edu ) for sharing, analysis and use in downstream applications. We enhanced the utility, transparency, and reproducibility of the existing mAb collection by using these sequences to develop recombinant mAbs. This enabled their subsequent engineering into alternate forms with distinct utility, including alternate modes of detection in multiplexed labeling, and as miniaturized single chain variable fragments or scFvs. The NeuroMabSeq website and database and the corresponding recombinant antibody collection together serve as a public DNA sequence repository of mouse mAb heavy and light chain variable domain sequences and as an open resource for enhancing dissemination and utility of this valuable collection of validated mAbs.
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Objective: Single-cell RNA sequencing (scRNA-seq) is a powerful technology that can be applied to the cells populating the whole knee in the study of joint pathology. The knee contains cells embedded in hard structural tissues, cells in softer tissues and membranes, and immune cells. This creates a technical challenge in preparing a viable and representative cell suspension suitable for use in scRNA-seq in minimal time, where under-digestion may exclude cells in hard tissues, over-digestion may damage soft tissue cells, and prolonged digestion may induce phenotypic drift. We developed a rapid two-stage digestion protocol to overcome these difficulties. Design: A two-stage digest consisting of first collagenase IV, an intermediate cell recovery, then collagenase II on the remaining hard tissue. Cells were sequenced on the 10x Genomics platform. Results: We observed consistent cell numbers and viable single cell suspensions suitable for scRNA-seq analysis. Comparison of contralateral knees and separate mice showed reproducible cell yields and gene expression patterns by similar cell-types. A diverse collection of structural and immune cells were captured with a majority from immune origins. Two digestions were necessary to capture all cell-types. Conclusions: The knee contains a diverse mixture of stromal and immune cells that may be crucial for the study of osteoarthritis. The two-stage digestion presented here reproducibly generated highly viable and representative single-cell suspension for sequencing from the whole knee. This protocol facilitates transcriptomic studies of the joint as a complete organ.
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Estimating cell type composition of blood and tissue samples is a biological challenge relevant in both laboratory studies and clinical care. In recent years, a number of computational tools have been developed to estimate cell type abundance using gene expression data. Although these tools use a variety of approaches, they all leverage expression profiles from purified cell types to evaluate the cell type composition within samples. In this study, we compare 12 cell type quantification tools and evaluate their performance while using each of 10 separate reference profiles. Specifically, we have run each tool on over 4000 samples with known cell type proportions, spanning both immune and stromal cell types. A total of 12 of these represent in vitro synthetic mixtures and 300 represent in silico synthetic mixtures prepared using single-cell data. A final 3728 clinical samples have been collected from the Framingham cohort, for which cell populations have been quantified using electrical impedance cell counting. When tools are applied to the Framingham dataset, the tool Estimating the Proportions of Immune and Cancer cells (EPIC) produces the highest correlation, whereas Gene Expression Deconvolution Interactive Tool (GEDIT) produces the lowest error. The best tool for other datasets is varied, but CIBERSORT and GEDIT most consistently produce accurate results. We find that optimal reference depends on the tool used, and report suggested references to be used with each tool. Most tools return results within minutes, but on large datasets runtimes for CIBERSORT can exceed hours or even days. We conclude that deconvolution methods are capable of returning high-quality results, but that proper reference selection is critical.
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Transcriptoma , Algoritmos , Biología Computacional/métodos , Simulación por Computador , Perfilación de la Expresión Génica/métodos , HumanosRESUMEN
BACKGROUND: C. psittaci has recently emerged as an equine abortigenic pathogen causing significant losses to the Australian Thoroughbred industry, while Equine herpesvirus-1 (EHV-1) is a well-recognized abortigenic agent. Diagnosis of these agents is based on molecular assays in diagnostic laboratories. In this study, we validated C. psittaci and newly developed EHV-1 Loop Mediated Isothermal Amplification (LAMP) assays performed in a real-time fluorometer (rtLAMP) against the reference diagnostic assays. We also evaluated isothermal amplification using commercially available colorimetric mix (cLAMP), and SYBR Green DNA binding dye (sgLAMP) for "naked eye" end-point detection when testing 'real-world' clinical samples. Finally, we applied the C. psittaci LAMP assays in two pilot Point-of-Care (POC) studies in an equine hospital. RESULTS: The analytical sensitivity of C. psittaci and EHV-1 rt-, and colorimetric LAMPs was determined as one and 10 genome equivalents per reaction, respectively. Compared to reference diagnostic qPCR assays, the C. psittaci rtLAMP showed sensitivity of 100%, specificity of 97.5, and 98.86% agreement, while EHV-1 rtLAMP showed 86.96% sensitivity, 100% specificity, and 91.43% agreement. When testing rapidly processed clinical samples, all three C. psittaci rt-, c-, sg-LAMP assays were highly congruent with each other, with Kappa values of 0. 906 for sgLAMP and 0. 821 for cLAMP when compared to rtLAMP. EHV-1 testing also revealed high congruence between the assays, with Kappa values of 0.784 for cLAMP and 0.638 for sgLAMP when compared to rtLAMP. The congruence between LAMP assays and the C. psittaci or EHV-1 qPCR assays was high, with agreements ranging from 94.12 to 100% for C. psittaci, and 88.24 to 94.12% for EHV-1, respectively. At the POC, the C. psittaci rt- and c-LAMP assays using rapidly processed swabs were performed by technicians with no prior molecular experience, and the overall congruence between the POC C. psittaci LAMPs and the qPCR assays ranged between 90.91-100%. CONCLUSIONS: This study describes reliable POC options for the detection of the equine pathogens: C. psittaci and EHV-1. Testing 'real-world' samples in equine clinical setting, represents a proof-of-concept that POC isothermal diagnostics can be applied to rapid disease screening in the equine industry.
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Infecciones por Herpesviridae/veterinaria , Enfermedades de los Caballos/diagnóstico , Psitacosis/veterinaria , Animales , Chlamydophila psittaci/aislamiento & purificación , Femenino , Fluorometría/métodos , Fluorometría/veterinaria , Infecciones por Herpesviridae/diagnóstico , Herpesvirus Équido 1/aislamiento & purificación , Caballos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/veterinaria , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas de Amplificación de Ácido Nucleico/veterinaria , Sistemas de Atención de Punto , Psitacosis/diagnóstico , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: There is little consensus on factors associated with survival in foals with septic arthritis and limited data on long-term racing performance of Thoroughbred foals treated for septic arthritis. A more thorough understanding of short- and long-term outcome is necessary to help inform owners, and subsequently guide treatment. OBJECTIVES: To investigate factors associated with survival, and to analyse racing performance of foals with septic arthritis compared with their maternal siblings. STUDY DESIGN: Retrospective cohort and a case-control study. METHODS: Veterinary clinical records of Thoroughbred foals ≤180 days old that underwent arthroscopic, cannulae or through-and-through needle lavage for the treatment of septic arthritis between 2009 and 2015 were reviewed. Data included signalment, and clinicopathological information. The dam's foaling records were reviewed and the lifetime racing records were obtained for affected foals and two of their maternal siblings. Logistic regression analysis was used to determine factors associated with survival to discharge or racing. Comparisons between treated foals and their maternal siblings were made. RESULTS: Ninety (78%) of 115 foals diagnosed with septic arthritis were discharged alive. Foals <26 days old at the time of admission were five times less likely (P = .003) and foals with concurrent multisystemic disease were six times less likely (P = .02) to be discharged alive. Sixty (67%) foals discharged alive started in ≥1 race, and there was no difference in the proportion of foals that started in a race or racing performance between foals treated for septic arthritis and their maternal siblings. MAIN LIMITATIONS: Retrospective study design, limited number of foals with multiple joint involvement and failure to accurately record duration of clinical signs. CONCLUSIONS: Foals treated for septic arthritis at the Scone Equine Hospital, New South Wales, Australia had a good prognosis for survival, and for this cohort, foals that survived to discharge had a similar ability to race as their maternal siblings.
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Artritis Infecciosa , Enfermedades de los Caballos , Condicionamiento Físico Animal , Deportes , Animales , Animales Recién Nacidos , Artritis Infecciosa/veterinaria , Estudios de Casos y Controles , Caballos , Humanos , Estudios Retrospectivos , HermanosRESUMEN
Improvements in high-throughput sequencing makes targeted amplicon analysis an ideal method for the study of human and environmental microbiomes by undergraduates. Multiple bioinformatics programs are available to process and interpret raw microbial diversity datasets, and the choice of programs to use in curricula is largely determined by student learning goals. Many of the most commonly used microbiome bioinformatics platforms offer end-to-end data processing and data analysis using a command line interface (CLI), but the downside for novice microbiome researchers is the steep learning curve often required. Alternatively, some sequencing providers include processing of raw data and taxonomy assignments as part of their pipelines. This, when coupled with available web-based or graphical user interface (GUI) analysis and visualization tools, eliminates the need for students or instructors to have extensive CLI experience. However, lack of universal data formats can make integration of these tools challenging. For example, tools for upstream and downstream analyses frequently use multiple different data formats which then require writing custom scripts or hours of manual work to make the files compatible. Here, we describe a microbial ecology bioinformatics curriculum that focuses on data analysis, visualization, and statistical reasoning by taking advantage of existing web-based and GUI tools. We created the Program for Unifying Microbiome Analysis Applications (PUMAA), which solves the problem of inconsistent files by formatting the output files from several raw data processing programs to seamlessly transition to a suite of GUI programs for analysis and visualization of microbiome taxonomic and inferred functional profiles. Additionally, we created a series of tutorials to accompany each of the microbiome analysis curricular modules. From pre- and post-course surveys, students in this curriculum self-reported conceptual and confidence gains in bioinformatics and data analysis skills. Students also demonstrated gains in biologically relevant statistical reasoning based on rubric-guided evaluations of open-ended survey questions and the Statistical Reasoning in Biology Concept Inventory. The PUMAA program and associated analysis tutorials enable students and researchers with no computational experience to effectively analyze real microbiome datasets to investigate real-world research questions.
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BACKGROUND: Recent advancements in next-generation sequencing have rapidly improved our ability to study genomic material at an unprecedented scale. Despite substantial improvements in sequencing technologies, errors present in the data still risk confounding downstream analysis and limiting the applicability of sequencing technologies in clinical tools. Computational error correction promises to eliminate sequencing errors, but the relative accuracy of error correction algorithms remains unknown. RESULTS: In this paper, we evaluate the ability of error correction algorithms to fix errors across different types of datasets that contain various levels of heterogeneity. We highlight the advantages and limitations of computational error correction techniques across different domains of biology, including immunogenomics and virology. To demonstrate the efficacy of our technique, we apply the UMI-based high-fidelity sequencing protocol to eliminate sequencing errors from both simulated data and the raw reads. We then perform a realistic evaluation of error-correction methods. CONCLUSIONS: In terms of accuracy, we find that method performance varies substantially across different types of datasets with no single method performing best on all types of examined data. Finally, we also identify the techniques that offer a good balance between precision and sensitivity.
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Algoritmos , Secuenciación de Nucleótidos de Alto Rendimiento , Benchmarking , Biología Computacional/métodos , Humanos , Receptores de Antígenos de Linfocitos T/genética , Virus/genética , Secuenciación Completa del GenomaRESUMEN
Developing new software tools for analysis of large-scale biological data is a key component of advancing modern biomedical research. Scientific reproduction of published findings requires running computational tools on data generated by such studies, yet little attention is presently allocated to the installability and archival stability of computational software tools. Scientific journals require data and code sharing, but none currently require authors to guarantee the continuing functionality of newly published tools. We have estimated the archival stability of computational biology software tools by performing an empirical analysis of the internet presence for 36,702 omics software resources published from 2005 to 2017. We found that almost 28% of all resources are currently not accessible through uniform resource locators (URLs) published in the paper they first appeared in. Among the 98 software tools selected for our installability test, 51% were deemed "easy to install," and 28% of the tools failed to be installed at all because of problems in the implementation. Moreover, for papers introducing new software, we found that the number of citations significantly increased when authors provided an easy installation process. We propose for incorporation into journal policy several practical solutions for increasing the widespread installability and archival stability of published bioinformatics software.
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Biología Computacional/métodos , Difusión de la Información/métodos , Almacenamiento y Recuperación de la Información/métodos , Investigación Biomédica , Bases de Datos Factuales , Humanos , Internet , Programas Informáticos/tendenciasRESUMEN
PURPOSE: We examined the concerns that nurses perceive patients to have, whether these are congruent with patients' concerns and whether they vary according to cancer site. We also examined Distress Thermometer scores according to cancer site. METHOD: A cross-sectional survey design: (i) secondary analysis of an existing Holistic Needs Assessment (HNA) and Distress Thermometer (DT) dataset was used, (ii) a survey of specialist nurse teams to identify their perceptions of patient concerns. Data collected between January 2015 and June 2016 from the HNA database from one NHS Trust in England (nâ¯=â¯1233 patients). Specialist nurse teams for breast, colorectal, gynaecology, skin and urology cancers identified the concerns that they perceived their patients would report. RESULTS: The HNA showed high internal consistency (Cronbach's alpha 0.86). Across the five cancer sites, nurses identified between 3 and 6 of the top ten concerns (TTC) expressed by patients, with wide variation across cancer sites. Nine of the TTC were significantly associated (pâ¯<â¯0.05) with a specific cancer site. The breast and gynaecological cancer groups both recorded significantly higher median Distress Thermometer scores than the urology, skin and colorectal cancer groups (Kruskall-Wallis χ2 (4, nâ¯=â¯1228) 186.695, p=<.01). CONCLUSIONS: One of the aims of the eHNA is to enable service delivery appropriate to patient needs. Our findings suggest that this will only be achieved if eHNA is examined, and services developed, by individual cancer site. The misconception of patient needs by specialist nurses underscores the importance of review of information provided by patients during consultations.
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Adaptación Psicológica , Neoplasias/enfermería , Neoplasias/psicología , Personal de Enfermería en Hospital/psicología , Pacientes/psicología , Estrés Psicológico , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Inglaterra , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermería Oncológica , Encuestas y CuestionariosRESUMEN
INTRODUCTION: Antigen-specific immunotherapy could provide a targeted approach for the treatment of multiple sclerosis that removes the need for broad-acting immunomodulatory drugs. ATX-MS-1467 is a mixture of four peptides identified as the main immune-dominant disease-associated T-cell epitopes in myelin basic protein (MBP), an autoimmune target for activated autoreactive T cells in multiple sclerosis. Previous animal studies have shown that ATX-MS-1467 treatment prevented the worsening of signs of disease in experimental autoimmune encephalitis (EAE) in the humanized (DR2 × Ob1)F1 mouse in a dose-dependent fashion. METHODS AND RESULTS: Our study extends these observations to show that subcutaneous treatment with 100 µg of ATX-MS-1467 after induction of EAE in the same mouse model reversed established clinical disability (p < 0.0001) and histological markers of inflammation and demyelination (p < 0.001) compared with vehicle-treated animals; furthermore, in longitudinal magnetic resonance imaging analyses, disruption of blood-brain barrier integrity was reversed, compared with vehicle-treated animals (p < 0.05). Chronic treatment with ATX-MS-1467 was associated with an enduring shift from a pro-inflammatory to a tolerogenic state in the periphery, as shown by an increase in interleukin 10 secretion, relative to interleukin 2, interleukin 17 and interferon γ, a decrease in splenocyte proliferation and an increase in interleukin 10+ Foxp3- T cells in the spleen. CONCLUSION: Our results suggest that ATX-MS-1467 can induce splenic iTregs and long-term tolerance to MBP with the potential to partially reverse the pathology of multiple sclerosis, particularly during the early stages of the disease. FUNDING: EMD Serono, Inc., a business of Merck KGaA.
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Over the past 75 years, birefringent filter technology has evolved significantly. For nearly that same period of time, these filters have been designed and used by solar scientists to study the Sun. Prior to assembling these types of filters, each component, e.g., polarizers and wave plates, is characterized to determine its polarimetric parameters to ensure the desired filter design performance. With time and cost becoming an ever increasing issue, it is imperative to test components designated for a birefringent filter efficiently. This article addresses a shift to increased efficiency when testing components of very low volume (<5 units) solar research filters that minimizes high-priced hardware expenditures, i.e., Mueller matrix spectropolarimeter.
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Anestésicos por Inhalación/efectos adversos , Trastorno Bipolar/inducido químicamente , Óxido Nitroso/efectos adversos , Complicaciones del Embarazo/inducido químicamente , Adulto , Trastorno Bipolar/complicaciones , Trastorno Bipolar/tratamiento farmacológico , Femenino , Humanos , Embarazo , RecurrenciaRESUMEN
Type I interferons (IFNs) bind IFNAR receptors and activate Jak kinases and Stat transcription factors to stimulate the transcription of genes downstream from IFN-stimulated response elements. In this study, we analyze the role of protein palmitoylation, a reversible post-translational lipid modification, in the functional properties of IFNAR. We report that pharmacological inhibition of protein palmitoylation results in severe defects of IFN receptor endocytosis and signaling. We generated mutants of the IFNAR1 subunit of the type I IFN receptor, in which each or both of the two cysteines present in the cytoplasmic domain are replaced by alanines. We show that cysteine 463 of IFNAR1, the more proximal of the two cytoplasmic cysteines, is palmitoylated. A thorough microscopic and biochemical analysis of the palmitoylation-deficient IFNAR1 mutant revealed that IFNAR1 palmitoylation is not required for receptor endocytosis, intracellular distribution, or stability at the cell surface. However, the lack of IFNAR1 palmitoylation affects selectively the activation of Stat2, which results in a lack of efficient Stat1 activation and nuclear translocation and IFN-alpha-activated gene transcription. Thus, receptor palmitoylation is a previously undescribed mechanism of regulating signaling activity by type I IFNs in the Jak/Stat pathway.
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Antivirales/farmacología , Interferón-alfa/farmacología , Ácido Palmítico/metabolismo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Receptor de Interferón alfa y beta/metabolismo , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT2/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Transporte Activo de Núcleo Celular/genética , Sustitución de Aminoácidos , Animales , Línea Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Endocitosis/efectos de los fármacos , Endocitosis/genética , Humanos , Ratones , Mutación Missense , Procesamiento Proteico-Postraduccional/genética , Estructura Terciaria de Proteína/genética , Receptor de Interferón alfa y beta/genética , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT2/genética , Transducción de Señal/efectos de los fármacosRESUMEN
OBJECTIVE: Our objective was to assess the role of fusion positron emission tomography-computed tomography (PET-CT) in staging patients for minimally invasive oesophagectomy (MIO) with potentially resectable disease from the perspective of a multidisciplinary team (MDT) deciding on operability with conventional staging investigations. METHODS: Fifty consecutive patients presenting with potentially operable oesophageal or oesophagogastric junctional tumours were staged with computed tomography (CT) and endoluminal ultrasound (EUS). The MDT categorised patients as group A (n=33; CT N0M0) or group B (n=17; CT N1/possible M1). All patients underwent FDG PET-CT. Patients with localised disease (at T3), including single level N1 disease on PET-CT, were deemed suitable for induction chemotherapy followed by surgery. RESULTS: PET-CT re-categorised 12% of patients as inoperable on grounds of distant metastases (four in group A, two in group B). Five patients did not proceed to resection for other reasons. Two had metastatic disease at thoracoscopy. Resection specimens (n=37) contained 24 nodes (median). Compared with pN status, positive predictive value of PET-CT was 40% and negative predictive value was 43%. The expected PET-CT N1 group had the highest mean number of involved nodes. Median survival for all patients (n=50) was 31.9 months for group A compared with 17.3 months for group B (not statistically significant). There was no significant difference between patients who were PET-CT N0 or N1 in survival or disease-free survival in patients undergoing surgery (n=37). CONCLUSIONS: PET-CT informs the MDT decision to operate in avoiding futile surgery in stage IV disease or widespread nodal disease. In this study, overall PET-CT N1 status has low positive and negative predictive value for overall pN status.
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Neoplasias Esofágicas/diagnóstico por imagen , Unión Esofagogástrica/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Toma de Decisiones , Métodos Epidemiológicos , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Esofagectomía , Unión Esofagogástrica/cirugía , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Estadificación de Neoplasias/métodos , Grupo de Atención al Paciente , Selección de Paciente , Tomografía de Emisión de PositronesRESUMEN
For over two decades there have been intense efforts aimed at the development of alternatives to conventional magnets, particularly materials comprised in part or wholly of molecular components. Such alternatives offer the prospect of realizing magnets fabricated through controlled, low-temperature, solution-based chemistry, as opposed to high-temperature metallurgical routes, and also the possibility of tuning magnetic properties through synthesis. However, examples of magnetically ordered molecular materials at or near room temperature are extremely rare, and the properties of these materials are often capricious and difficult to reproduce. Here we present a versatile solution-based route to a new class of metal-organic materials exhibiting magnetic order well above room temperature. Reactions of the metal (M) precursor complex bis(1,5-cyclooctadiene)nickel with three different organics A-TCNE (tetracyanoethylene), TCNQ (7,7,8,8-tetracyanoquinodimethane) or DDQ (2,3-dichloro-5,6-dicyano-1,4-benzoquinone)--proceed via electron transfer from nickel to A and lead to materials containing Ni(II) ions and reduced forms of A in a 2:1 Ni:A ratio--that is, opposite to that of conventional (low Curie temperature) MA(2)-type magnets. These materials also contain oxygen-based species within their architectures. Magnetic characterization of the three compounds reveals spontaneous field-dependent magnetization and hysteresis at room temperature, with ordering temperatures well above ambient. The unusual stoichiometry and striking magnetic properties highlight these three compounds as members of a class of stable magnets that are at the interface between conventional inorganic magnets and genuine molecule-based magnets.
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Type I (alpha/beta) and type II (gamma) interferons (IFNs) bind to distinct receptors, although they activate the same signal transducer and activator of transcription, Stat1, raising the question of how signal specificity is maintained. Here, we have characterized the sorting of IFN receptors (IFN-Rs) at the plasma membrane and the role it plays in IFN-dependent signaling and biological activities. We show that both IFN-alpha and IFN-gamma receptors are internalized by a classical clathrin- and dynamin-dependent endocytic pathway. Although inhibition of clathrin-dependent endocytosis blocked the uptake of IFN-alpha and IFN-gamma receptors, this inhibition only affected IFN-alpha-induced Stat1 and Stat2 signaling. Furthermore, the antiviral and antiproliferative activities induced by IFN-alpha but not IFN-gamma were also affected. Finally, we show that, unlike IFN-alpha receptors, activated IFN-gamma receptors rapidly become enriched in plasma membrane lipid microdomains. We conclude that IFN-R compartmentalization at the plasma membrane, through clathrin-dependent endocytosis and lipid-based microdomains, plays a critical role in the signaling and biological responses induced by IFNs and contributes to establishing specificity within the Jak/Stat signaling pathway.
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Endocitosis , Interferón-alfa/metabolismo , Interferón gamma/metabolismo , Microdominios de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Receptores de Interferón/metabolismo , Transporte Activo de Núcleo Celular , Membrana Celular/metabolismo , Clatrina/metabolismo , Endocitosis/efectos de los fármacos , Humanos , Interferón-alfa/farmacología , Interferón gamma/farmacología , Transporte de Proteínas , Receptor de Interferón alfa y beta , Elementos de Respuesta/efectos de los fármacos , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT2/metabolismo , Transcripción Genética/efectos de los fármacosRESUMEN
The characterization of an electrochemically created Pt/Zn alloy by Auger electron spectroscopy is presented indicating the formation of the alloy, the oxidation of the alloy, and the room temperature diffusion of the Zn into the Pt regions. The Pt/Zn alloy is stable up to 1.2 V/RHE and can only be removed with the oxidation of the base Pt metal either electrochemically or in aqua regia. The Pt/Zn alloy was tested for its effectiveness toward oxygen reduction. Kinetics of the oxygen reduction reaction (ORR) were measured using a rotating disk electrode (RDE), and a 30 mV anodic shift in the potential of ORR was found when comparing the Pt/Zn alloy to Pt. The Tafel slope was slightly smaller than that measured for the pure Pt electrode. A simple procedure for electrochemically modifying a Pt-containing gas diffusion electrode (GDE) with Zn was developed. The Zn-treated GDE was pressed with an untreated GDE anode, and the created membrane electrode assembly was tested. Fuel cell testing under two operating conditions (similar anode and cathode inlet pressures, and a larger cathode inlet pressure) indicated that the 30 mV shift observed on the RDE was also evident in the fuel cell tests. The high stability of the Pt/Zn alloy in acidic environments has a potential benefit for fuel cell applications.
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OBJECTIVE: To assess if posterior juxtascleral application of 40 mg triamcinolone acetonide (TA), given at the same time as initial photodynamic therapy (PDT) for predominantly classic choroidal neovascularization (CNV) related to age-related macular degeneration affects lesion growth at 3 and 6 months. DESIGN: Comparative (nonrandomized) interventional study. PARTICIPANTS: The study group consists of 38 eyes of 38 patients. The control group consists of 73 eyes of 73 patients. METHODS: Comparison of 2 consecutive case series collected at different times. The study group had a posterior juxtascleral TA with their initial PDT treatment. The controls were treated with PDT alone. All patients were reviewed at 1, 3, and 6 months. MAIN OUTCOME MEASURES: Change in total lesion size; secondary outcomes: area of leak, best-corrected visual acuity, number of treatments, and intraocular pressure. RESULTS: There was significantly less growth of total lesion at 3 months (mean difference = 2.47 mm2; 95% confidence interval (CI): +1.22 to +3.72 mm2; P = 0.0002) and 6 months (mean difference = 2.88 mm2; 95% CI: +0.61 to +5.15 mm2; P = 0.0134) in patients given TA with PDT compared with PDT alone. There was also a significantly smaller residual area of leak at 3 months in the study group (mean difference = 1.07 mm2; 95% CI: +0.16 to +1.97 mm2; P = 0.02). At 6 months, the residual area of leak between the 2 groups became comparable (mean difference = 0.13 mm2; 95% CI = -1.59 to +1.33 mm2; P = 0.86). Mean number of letters lost on the logarithm of the minimum angle of resolution chart at 6 months was 9.1 letters (standard error of the mean [SEM] = 2.21) in the study group compared with 12.4 letters (SEM = 1.91) in the control group (P = 0.30). At 6 months, 10 of 36 eyes (27.8%) in the study group showed > or =15 letters loss, compared with 29 of 73 eyes (39.7%) in the control group. Intraocular pressure was raised in 4 of 38 eyes (10.5%). Fewer retreatments were required in the TA with PDT group (2.03 compared with 2.47 [P = 0.006]). CONCLUSIONS: Posterior juxtascleral placement of TA with PDT at baseline significantly reduces CNV growth at 3 and 6 months. Fewer retreatments were required. Visual outcome may be improved, although we did not show a statistically significant improvement with this sample size. A larger, randomized trial with longer follow-up is justified.
Asunto(s)
Neovascularización Coroidal/tratamiento farmacológico , Glucocorticoides/administración & dosificación , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/uso terapéutico , Triamcinolona Acetonida/administración & dosificación , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Neovascularización Coroidal/etiología , Neovascularización Coroidal/patología , Tejido Conectivo/efectos de los fármacos , Femenino , Angiografía con Fluoresceína , Humanos , Inyecciones , Degeneración Macular/complicaciones , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/patología , Masculino , Persona de Mediana Edad , Esclerótica/efectos de los fármacos , Resultado del Tratamiento , Verteporfina , Agudeza VisualRESUMEN
OBJECTIVE: To assess the intraobserver and interobserver reliability of recording uniocular fields of fixation using a modified perimeter technique in healthy subjects and patients with Graves orbitopathy (GO). Patients with restrictive myopathies, particularly GO, require accurate measurement of monocular excursions. These ductions are recorded in 4 to 12 directions of gaze using a perimeter, producing a plot known as a uniocular field of fixation. While 4 direction plots give limited information on vertical muscles, recording 12 directions is time consuming and uncomfortable. This modified technique uses the 6 directions of gaze corresponding to the primary field of action of each muscle. METHODS: A single observer measured modified uniocular fields of fixation in 35 healthy subjects aged 20 to 60 years to establish normal and age-related ranges for all ductions. Fifteen subjects underwent measurement on 5 separate occasions by the same observer to establish intraobserver reproducibility. A second observer independently performed measurements in 10 of the subjects to determine interobserver reproducibility. Reliability was compared with that measured in 29 patients with GO. RESULTS: The technique was reproducible to within 4 degrees for healthy subjects undergoing assessment by a single observer. When results of 2 observers were compared, the coefficient of repeatability was 7.9 degrees . For subjects with GO, however, maximal variability was 7.8 degrees . For clinical purposes, only a change of 8 degrees or more can be assumed to be significant. CONCLUSIONS: This technique offers advantages for assessing any restrictive myopathy, including GO to within 8 degrees . This level of accuracy is likely to be similar in other centers, and has implications for interpreting GO outcome measures, where 5 degrees was previously taken to represent significant change.