RESUMEN
In the field of augmented reality, there is a need for very bright color microdisplays to meet the user specifications. Today, one of the most promising technology to manufacture such displays involves a blue micro-LED technology and quantum dots-based color conversion layers. Despite recent progress, the external power conversion efficiencies (EPCE) of these layers remain under â¼25%, below the needs (>40%) to reach a white luminance of 100,000 cd/m2. In this work, we have synthesized CdSexS1-x nanoplatelet-based conversion layers for red and green conversion, and measured their absorption properties and EPCE performances with respect to layer thickness. On this basis, a model was developed that reliably predicts the layer EPCE while using only few input data, namely the layer absorption coefficients and the photoluminescence quantum yield (PLQY) of color photoresist. It brings a new insight into the conversion process at play at a micro-LED level and provides a simple method for extensive optimization of conversion materials. Finally, this study highlights the outstanding red conversion efficiency of photoresist layers made of core-double shell CdSexS1-x nanoplatelets with 31% EPCE (45% external PLQY) for 8 µm-thick conversion layer.
RESUMEN
OBJECTIVE: To establish an ELISA for detection of serum total IgE concentration in dogs and to analyze IgE values in a dog colony. ANIMALS: 147 healthy Beagles (31 males and 116 females). PROCEDURE: 2 canine IgE-specific polyclonal antibodies elicited by 2 recombinant fragments of the epsilon chain in hens were used to develop a capture ELISA specific for serum total IgE concentration. The IgE values were calculated by comparing serum dose-response curves (1:50 to 1:6,400) with a reference serum pool assigned 100 relative ELISA units (REU). Results-Mean IgE concentration in female Beagles was 51.2 REU (range, 0 to 337.8 REU; median, 31.4 REU), whereas mean IgE concentration in male dogs was only 7.5 REU (range, 0 to 32.6 REU; mean, 3.6 REU). Distribution of IgE values was skewed; approximately 80% of dogs had IgE values < 50 REU. Analysis of natural logarithmically transformed IgE values indicated that sex and age significantly (P < 0.05) influenced IgE values; mean serum IgE values increased until the age of 4 years. Heritability estimates of IgE concentration indicated a trend toward a genetic influence. CONCLUSION: A reliable capture ELISA specific for canine IgE was developed. Serum total IgE values vary with age and sex in the sample population. CLINICAL RELEVANCE: Serum total IgE concentration can now be evaluated in various dog breeds and, subsequently, in dogs with IgE-mediated diseases provided that these significant influences are accounted for. Serum total IgE values may then prove to be of diagnostic value, similar to their use in human beings.
Asunto(s)
Perros/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Inmunoglobulina E/sangre , Factores de Edad , Animales , Anticuerpos/análisis , Cruzamiento , Perros/sangre , Relación Dosis-Respuesta Inmunológica , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Masculino , Valores de Referencia , Sensibilidad y Especificidad , Factores SexualesRESUMEN
Total serum immunoglobulin (Ig) E and A levels were analysed in 233 healthy dogs as basis for comparison with atopic dogs in future studies. They were measured by ELISA in a group of non- colonised dogs of various breeds (group A) and three groups of colonised dogs including one German Shepherd and two Beagle kennels (groups B-D). IgE levels from non-colonised dogs were significantly higher than the ones of German Shepherds and Beagles C (P<0.05). IgA levels were alike in all groups except for the German Shepherds which displayed the lowest levels. Age and sex were not identified as common significant cofactors for IgE and IgA levels in all groups and IgE levels correlated negatively with IgA only in non-colonised dogs. In conclusion, IgE and IgA levels seem to be mainly influenced by genetic background. Thus use of total serum IgE as a diagnostic tool in the atopic dogs required extensive family data and therefore appears most suitable for research purposes within specific, well defined dog populations.
Asunto(s)
Perros/inmunología , Inmunoglobulina A/sangre , Inmunoglobulina E/sangre , Animales , Enfermedades de los Perros/inmunología , Ambiente , Ensayo de Inmunoadsorción Enzimática/veterinaria , Hipersensibilidad/sangre , Hipersensibilidad/inmunología , Hipersensibilidad/veterinaria , Valores de ReferenciaRESUMEN
Two recombinant [His]6-tagged fragments of the canine immunoglobulin E (IgE) heavy chain (second domain: IgEf2 and third and fourth domains: IgEf3/4) were cloned, expressed in Escherichia coli (E. coli) as [His]6-tagged proteins, and affinity-purified over nickel-nitrilotriacetic acid columns. The recombinant proteins were used to immunize hens. The raised and affinity-purified chicken antibodies (Ab) isolated from egg yolk exhibited specific binding to the respective recombinant canine IgE fragment (IgEf) on immunoblots and displayed high titers against the IgEf in ELISA. Immunoblotting of canine serum separated by PAGE under native conditions with the IgEf2- and IgEf3/4-specific Ab resulted in staining of a protein of approximately 180 kilodaltons (kD). The IgEf3/4-specific Ab further recognized an 80 kD protein in IgEf3/4-specific Ab affinity-enriched dog serum separated under denaturing conditions. In an ELISA for the detection of antigen-specific IgE in dog serum, reduced binding of the IgEf-specific Ab was observed after heat treatment of the dog serum. The reactivity of both of the raised chicken Ab was only present in postimmune reagents and could only be inhibited by preincubation with the IgEf used for immunization and not with dog immunoglobulin G, E. coli extract, or with a nonrelevant recombinant [His]6-tagged protein. In immunohistochemistry, the IgEf3/4-specific Ab specifically recognized cells in paraffin-embedded tissue sections of lymph nodes. Furthermore, both of the IgEf-specific Ab elicited positive immediate type 1 skin reactions in dogs. Semiquantitative assessment of total serum IgE in dogs was developed using IgEf2-specific Ab as coating reagent and the biotinylated IgEf3/4-specific Ab as developing Ab in ELISA. In conclusion, both IgEf-specific Ab recognize native dog IgE with the advantages that they are directed against different and known constant domains of the IgE molecule, and that they can be used for immunohistochemistry on paraffin-embedded tissue. The two dog IgE-specific Ab could initiate clinical research on the involvement of immediate-type hypersensitivity reactions in dogs.