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1.
Clin Exp Allergy ; 47(8): 1032-1037, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28544327

RESUMEN

BACKGROUND: Food allergies pose a considerable world-wide public health burden with incidence as high as one in ten in 12-month-old infants. Few food allergy genetic risk variants have yet been identified. The Th2 immune gene IL13 is a highly plausible genetic candidate as it is central to the initiation of IgE class switching in B cells. OBJECTIVE: Here, we sought to investigate whether genetic polymorphisms at IL13 are associated with the development of challenge-proven IgE-mediated food allergy. METHOD: We genotyped nine IL13 "tag" single nucleotide polymorphisms (tag SNPs) in 367 challenge-proven food allergic cases, 199 food-sensitized tolerant cases and 156 non-food allergic controls from the HealthNuts study. 12-month-old infants were phenotyped using open oral food challenges. SNPs were tested using Cochran-Mantel-Haenszel test adjusted for ancestry strata. A replication study was conducted in an independent, co-located sample of four paediatric cohorts consisting of 203 food allergic cases and 330 non-food allergic controls. Replication sample phenotypes were defined by clinical history of reactivity, 95% PPV or challenge, and IL13 genotyping was performed. RESULTS: IL13 rs1295686 was associated with challenge-proven food allergy in the discovery sample (P=.003; OR=1.75; CI=1.20-2.53). This association was also detected in the replication sample (P=.03, OR=1.37, CI=1.03-1.82) and further supported by a meta-analysis (P=.0006, OR=1.50). However, we cannot rule out an association with food sensitization. Carriage of the rs1295686 variant A allele was also associated with elevated total plasma IgE. CONCLUSIONS AND CLINICAL RELAVANCE: We show for the first time, in two independent cohorts, that IL13 polymorphism rs1295686 (in complete linkage disequilibrium with functional variant rs20541) is associated with challenge-proven food allergy.


Asunto(s)
Alelos , Inmunoglobulina E/inmunología , Interleucina-13/genética , Desequilibrio de Ligamiento , Hipersensibilidad a Nueces y Cacahuetes , Polimorfismo de Nucleótido Simple , Células Th2/inmunología , Australia , Femenino , Humanos , Lactante , Interleucina-13/inmunología , Masculino , Metaanálisis como Asunto , Hipersensibilidad a Nueces y Cacahuetes/genética , Hipersensibilidad a Nueces y Cacahuetes/inmunología , Hipersensibilidad a Nueces y Cacahuetes/patología , Células Th2/patología
2.
Allergy ; 72(8): 1222-1231, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28042676

RESUMEN

BACKGROUND: Ecological evidence suggests vitamin D insufficiency (VDI) due to lower ambient ultraviolet radiation (UVR) exposure may be a risk factor for IgE-mediated food allergy. However, there are no studies relating directly measured VDI during early infancy to subsequent challenge-proven food allergy. OBJECTIVE: To prospectively investigate the association between VDI during infancy and challenge-proven food allergy at 1 year. METHODS: In a birth cohort (n = 1074), we used a case-cohort design to compare 25-hydroxyvitamin D3 (25(OH)D3 ) levels among infants with food allergy vs a random subcohort (n = 274). The primary exposures were VDI (25(OH)D3 <50 nM) at birth and 6 months of age. Ambient UVR and time in the sun were combined to estimate UVR exposure dose. IgE-mediated food allergy status at 1 year was determined by formal challenge. Binomial regression was used to examine associations between VDI, UVR exposure dose and food allergy and investigate potential confounding. RESULTS: Within the random subcohort, VDI was present in 45% (105/233) of newborns and 24% (55/227) of infants at 6 months. Food allergy prevalence at 1 year was 7.7% (61/786), and 6.5% (53/808) were egg-allergic. There was no evidence of an association between VDI at either birth (aRR 1.25, 95% CI 0.70-2.22) or 6 months (aRR 0.93, 95% CI 0.41-2.14) and food allergy at 1 year. CONCLUSIONS: There was no evidence that VDI during the first 6 months of infancy is a risk factor for food allergy at 1 year of age. These findings primarily relate to egg allergy, and larger studies are required.


Asunto(s)
Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/etiología , Inmunoglobulina E/inmunología , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/epidemiología , Factores de Edad , Estudios de Casos y Controles , Estudios de Cohortes , Dieta/efectos adversos , Exposición a Riesgos Ambientales , Femenino , Humanos , Inmunización , Lactante , Recién Nacido , Masculino , Vigilancia de la Población , Prevalencia , Factores de Riesgo , Rayos Ultravioleta , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/etiología
3.
Allergy ; 72(9): 1356-1364, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28213955

RESUMEN

BACKGROUND: A defective skin barrier is hypothesized to be an important route of sensitization to dietary antigens and may lead to food allergy in some children. Missense mutations in the serine peptidase inhibitor Kazal type 5 (SPINK5) skin barrier gene have previously been associated with allergic conditions. OBJECTIVE: To determine whether genetic variants in and around SPINK5 are associated with IgE-mediated food allergy. METHOD: We genotyped 71 "tag" single nucleotide polymorphisms (tag-SNPs) within a region spanning ~263 kb including SPINK5 (~61 kb) in n=722 (n=367 food-allergic, n=199 food-sensitized-tolerant and n=156 non-food-allergic controls) 12-month-old infants (discovery sample) phenotyped for food allergy with the gold standard oral food challenge. Transepidermal water loss (TEWL) measures were collected at 12 months from a subset (n=150) of these individuals. SNPs were tested for association with food allergy using the Cochran-Mantel-Haenszel test adjusting for ancestry strata. Association analyses were replicated in an independent sample group derived from four paediatric cohorts, total n=533 (n=203 food-allergic, n=330 non-food-allergic), mean age 2.5 years, with food allergy defined by either clinical history of reactivity, 95% positive predictive value (PPV) or challenge, corrected for ancestry by principal components. RESULTS: SPINK5 variant rs9325071 (A⟶G) was associated with challenge-proven food allergy in the discovery sample (P=.001, OR=2.95, CI=1.49-5.83). This association was further supported by replication (P=.007, OR=1.58, CI=1.13-2.20) and by meta-analysis (P=.0004, OR=1.65). Variant rs9325071 is associated with decreased SPINK5 gene expression in the skin in publicly available genotype-tissue expression data, and we generated preliminary evidence for association of this SNP with elevated TEWL also. CONCLUSIONS: We report, for the first time, association between SPINK5 variant rs9325071 and challenge-proven IgE-mediated food allergy.


Asunto(s)
Hipersensibilidad a los Alimentos/inmunología , Inmunoglobulina E/inmunología , Mutación/inmunología , Inhibidor de Serinpeptidasas Tipo Kazal-5/genética , Preescolar , Predisposición Genética a la Enfermedad , Humanos , Lactante , Fenotipo , Polimorfismo de Nucleótido Simple , Valor Predictivo de las Pruebas , Pérdida Insensible de Agua/genética
4.
Opt Express ; 24(3): 2590-5, 2016 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-26906831

RESUMEN

Optical properties of 4H-SiC were measured using time-domain and Fourier transform spectroscopy in the range of 0.1-20 THz. A high-transparency region was found between <0.1-10 THz. Based on the obtained data and published results, the refractive indices for o-wave and e-wave were approximated in the form of Sellmeier equations for the entire transparency range. Phase matched frequency conversion was found to be possible at wavelengths from the visible through the mid-IR and further into the far-IR (THz) region beyond 17 µm. Extremely low absorption coefficient, high damage threshold, and the possibility of phase matching make this material highly suited for high power THz optics and generation.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38529209

RESUMEN

Background: Hip resurfacing arthroplasty (HRA) provides an attractive alternative to total hip arthroplasty (THA) for the management of osteoarthritis in younger, more active patients; however, concerns persist over complications specific to HRA. The aims of this systematic review were to assess the documented long-term survival rates of the metal-on-metal BIRMINGHAM HIP Resurfacing System at a follow-up of at least 10 years and to analyze the functional outcomes and cause of failures. Methods: A systematic review was undertaken of all published cohort studies available in the MEDLINE, Cochrane, Embase, and PubMed research databases up to December 2021, as recommended by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data extraction was focused on survival rates, causes of failure, and functional outcomes. Survival estimates at 10 years were pooled in a meta-analysis, with each series weighted by its variance. Causes of failure were presented as a percentage of the pooled revisions. Results: A total of 11 studies were identified, encompassing 3,129 cases. Across the 9 studies that had reported a mean follow-up, the mean follow-up was 11.7 years (range, 9.55 to 13.7 years). We found a pooled 10-year survival rate of 95.5% (95% confidence interval, 93.4% to 97.1%). There were 149 revisions among the studies (range, 4 to 38 revisions per study), a rate of 4.8% of the total procedures performed. The 2 main causes of revision were aseptic loosening (20.1% of revisions) and adverse reactions to metal debris (20.1%). There were no revisions for dislocation. Of the studies that reported preoperative functional scores, all reported significant improvement in mean scores postoperatively except for 1 study in which the mean Tegner activity score did not significantly improve. Conclusions: When performed for appropriate indications, patients undergoing an HRA with use of the BIRMINGHAM HIP Resurfacing System can expect good implant survivorship at 10 years with acceptable functional results and low rates of dislocation and infection. This systematic review, however, confirms concerns regarding adverse reactions to metal debris as a leading cause of revision. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

6.
Appl Opt ; 52(19): 4433-7, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23842236

RESUMEN

A range of natural and artificial textiles are examined using terahertz time-domain spectroscopy. Different types of textiles are shown to have different terahertz optical properties, which may be employed for textile identification and to combat textile counterfeiting.

7.
Anal Bioanal Chem ; 402(1): 473-87, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22127575

RESUMEN

A suite of three green tea-containing Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST): SRM 3254 Camellia sinensis (Green Tea) Leaves, SRM 3255 Camellia sinensis (Green Tea) Extract, and SRM 3256 Green Tea-Containing Solid Oral Dosage Form. The materials are characterized for catechins, xanthine alkaloids, theanine, and toxic elements. As many as five methods were used in assigning certified and reference values to the constituents, with measurements carried out at NIST and at collaborating laboratories. The materials are intended for use in the development and validation of new analytical methods, and for use as control materials as a component in the support of claims of metrological traceability.


Asunto(s)
Camellia sinensis/química , Análisis de los Alimentos/normas , Té/química , Análisis de los Alimentos/métodos , Estándares de Referencia
8.
Dalton Trans ; 50(31): 10826-10837, 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34291274

RESUMEN

The lanthanide(iii) complexes (Gd, Eu, Dy, and Yb) of DOTA tris(amide) and bis(amide) derivatives (L1 and L2) featuring one redox active TEMPO arm were prepared. Ligand L2 harbours an alkyne fragment for further functionalization. The X-ray crystal structure of ligand L2 in complexation with Na+ was solved. The complexes showed in their CV one oxidation wave (0.26-0. 34 V vs. Fc+/Fc) due to an oxoammonium/nitroxide redox couple and a broad reduction corresponding to the nitroxide/hydroxylamine system. The Eu complexes demonstrated the presence of one water molecule in their coordination sphere. The nitroxide complexes were characterized by EPR spectroscopy, showing the typical 3-line pattern in the high temperature regime, which is quenched upon the addition of ascorbate (reduction into hydroxylamine). In their nitroxide form, the complexes show essentially no CEST peak. Conversely, the reduced complexes demonstrate a 12% CEST peak at 51 ppm, corresponding to the metal bound water molecule. Fast exchange precluded the CEST activity for the amide protons. All the complexes proved to be essentially non-toxic for M21 cells at concentrations up to 50 µM.


Asunto(s)
Compuestos Heterocíclicos con 1 Anillo , Elementos de la Serie de los Lantanoides , Medios de Contraste , Espectroscopía de Resonancia Magnética , Óxidos de Nitrógeno , Protones , Agua/química
9.
Dalton Trans ; 49(24): 8238-8246, 2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32510087

RESUMEN

The lanthanide complexes EuL3, GdL3, YbL3 and LuL3 of the N,N'-bis(2-hydroxy-di-3,5-tert-butylphenyl)amine were prepared. The X-Ray crystal structures of GdL3 and LuL3 demonstrated a nine-coordinate sphere with three ligand molecules under their anionic diamagnetic form (Cat-N-BQ)-. The complexes showed three oxidation events (Eox11/2 = 0.15-0.16 V, E1/22 = 0.51-55 V, and E1/23 = 0.75-0.78 V vs. Fc+/Fc) via cyclic voltammetry, corresponding to the successive oxidation of the aminophenolate moeities to iminosemiquinone species. The complexes GdL3 and YbL3 were characterized by EPR spectroscopy, allowing for the determination of the zero field splitting (ZFS) parameters in the first case. The monocations (LnL3)+ and monoanions (LnL3)- were electrochemically generated (Ln = Eu, Gd, Yb, Lu), as well as the dications YbL32+ and LuL32+. The spins are antiferromagnetically exchange coupled in the diradical species LuL32+ (|D| = 260 MHz, E = 0). All the complexes (incl. neutral) possess a strong absorption band in the NIR region (730-840 nm, ε > 19 mM-1 cm-1) corresponding to ligand-based transitions.

10.
J Cell Biol ; 119(6): 1523-39, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1469046

RESUMEN

We have used a combination of classical genetic, molecular genetic, histological, biochemical, and biophysical techniques to identify and characterize a null mutation of the myosin light chain-2 (MLC-2) locus of Drosophila melanogaster. Mlc2E38 is a null mutation of the MLC-2 gene resulting from a nonsense mutation at the tenth codon position. Mlc2E38 confers dominant flightless behavior that is associated with reduced wing beat frequency. Mlc2E38 heterozygotes exhibit a 50% reduction of MLC-2 mRNA concentration in adult thoracic musculature, which results in a commensurate reduction of MLC-2 protein in the indirect flight muscles. Indirect flight muscle myofibrils from Mlc2E38 heterozygotes are aberrant, exhibiting myofilaments in disarray at the periphery. Calcium-activated Triton X-100-treated single fiber segments exhibit slower contraction kinetics than wild type. Introduction of a transformed copy of the wild type MLC-2 gene rescues the dominant flightless behavior of Mlc2E38 heterozygotes. Wing beat frequency and single fiber contraction kinetics of a representative rescued line are not significantly different from those of wild type. Together, these results indicate that wild type MLC-2 stoichiometry is required for normal indirect flight muscle assembly and function. Furthermore, these results suggest that the reduced wing beat frequency and possibly the flightless behavior conferred by Mlc2E38 is due in part to slower contraction kinetics of sarcomeric regions devoid or partly deficient in MLC-2.


Asunto(s)
Drosophila melanogaster/fisiología , Vuelo Animal/fisiología , Contracción Muscular/fisiología , Músculos/fisiología , Miosinas/genética , Regulación Alostérica , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ATPasas Transportadoras de Calcio/metabolismo , Mapeo Cromosómico , Diploidia , Heterocigoto , Cinética , Datos de Secuencia Molecular , Músculos/anomalías , Músculos/ultraestructura , Mutación , Miofibrillas/ultraestructura , Miosinas/biosíntesis , Alas de Animales/fisiología
11.
Mol Cell Probes ; 23(2): 83-9, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19141318

RESUMEN

Coccidiosis of chickens is an economically important disease caused by infection with species of Eimeria. The oocysts of some of the seven recognized species are difficult to distinguish morphologically and for this reason diagnostic laboratories are increasingly utilizing DNA-based technologies for the specific identification of Eimeria. The real-time PCR provides both sensitivity and speed for the analysis of DNA samples, and the approach has the capability of quantifying DNA. Together with a protocol for the extraction of DNA directly from faecal samples, real-time PCR assays have been established for the detection and quantification of seven species of Eimeria that infect chickens in Australia. The assays target one genetic marker, the second internal transcribed spacer of nuclear ribosomal DNA (ITS-2), use TaqMan MGB technology with species-specific probes, and can be multiplexed in pairs such that the seven species of Eimeria can be screened in four reaction tubes. A test screen of commercial flocks identified more Eimeria-infected chickens than were detected by coproscopic examination for oocysts. These molecular assays can also be used for the quality control of mixed-species vaccines. The ability to multiplex the assays makes them particularly practical for screening samples from chickens with mixed-species infections where the relative abundance of each Eimeria species present is required.


Asunto(s)
Coccidiosis/veterinaria , Eimeria/genética , Eimeria/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Enfermedades de las Aves de Corral/diagnóstico , Enfermedades de las Aves de Corral/parasitología , Animales , Pollos , Coccidiosis/parasitología , ADN Espaciador Ribosómico/genética , Reproducibilidad de los Resultados
12.
Knee ; 26(4): 897-904, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31174980

RESUMEN

PURPOSE: The purpose of this study was to describe mid- to long-term outcomes of anterior cruciate ligament (ACL) reconstruction with simultaneous or staged medial unicompartmental knee replacement (UKR), and compare outcomes between (1) young patients aged younger than 55 at surgery and those older, (2) those with long-term follow-up greater than 10 years, (3) cemented and cementless UKR, and (4) compare outcomes to those with an intact ACL. PATIENTS AND METHODS: We identified knees with staged or simultaneous ACL reconstruction and medial UKR from a prospectively followed designer UKR cohort, and describe mean Oxford Knee Score (OKS), mean Tegner activity score and Kaplan-Meier survival estimates. We matched these knees to ACL-intact knees. RESULTS: Seventy-six consecutive UKR with staged or simultaneous ACL reconstruction were identified with mean six-year follow-up (range 1-15). There was significant improvement in OKS and Tegner score with surgery. At most recent follow-up, OKS was 41.0 (range 11 to 48), and Tegner score 3.6 (0 to 8). There were three revisions occurring at a mean of five years post-operatively. The five-, 10- and 15-year survival estimates were 97% (95% confidence interval [CI] 93-100), 92% (83-100), and 92% (83-100). There was no difference in functional scores or implant survival in young patients, those with long-term follow-up (>10 years), those with cementless fixation, or when compared to ACL intact knees. CONCLUSION: These results demonstrate excellent mid- to long-term function and survival of selected patients who have undergone ACL reconstruction and medial UKR. Their outcome was similar to those with intact ACLs.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior , Artroplastia de Reemplazo de Rodilla , Evaluación del Resultado de la Atención al Paciente , Adulto , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Prótesis de la Rodilla , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/cirugía , Diseño de Prótesis , Reoperación/estadística & datos numéricos
13.
J Bone Joint Surg Am ; 101(3): 270-275, 2019 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-30730487

RESUMEN

BACKGROUND: There is controversy about optimal limb alignment following knee replacement. An aim of using Oxford medial unicompartmental knee replacement (UKR) implants is to accurately restore normal ligament tension in the knee, thereby restoring normal kinematics. This return to normal tension typically results in a return to prearthritic alignment, which is frequently varus. The aim of this study was to investigate the relationship between postoperative limb alignment and postoperative patient-reported outcome and implant revision rate. METHODS: We used a consecutive cohort of 891 knees with cemented Oxford medial UKR implants with a mean 10-year follow-up and recorded alignment. We grouped knees according to postoperative mechanical alignment as marked varus (estimated at 10°), mild varus (estimated at 5°), neutral, and valgus. The mean Oxford Knee Score (OKS) was calculated at 5 and 10 years postoperatively. Revision risk was assessed by survival analysis and component-time incidence rates. RESULTS: Postoperatively, 67 (8%) of the 891 knees were in marked varus; 308 (35%), in mild varus; 508 (57%), in neutral; and 8 (1%), in valgus. The valgus group (8 knees) was too small for further analysis. The mean OKS (and standard deviation [SD]) at 10 years postoperatively was 41.7 ± 7 for marked varus, 40.5 ± 8 for mild varus, and 39.4 ± 9 for neutral alignment (p = 0.28). At 10 years, 92%, 85%, and 76% achieved a good or excellent OKS outcome, respectively (p = 0.02). Twelve-year survival rates were 93.3% for marked varus, 93.2% for mild varus, and 93.6% for neutral alignment, respectively (p = 0.53). Revision incidence rates per 100 component-years were 0.49 (95% confidence interval [CI], 0.2 to 1.5), 0.36 (95% CI, 0.2 to 0.7), and 0.54 (95% CI, 0.4 to 0.8), respectively, and were not significantly different (p = 0.53). CONCLUSIONS: Marked postoperative varus mechanical alignment of an estimated 10° was present in 8%, and mild varus of about 5° was present in 35%. Increasing varus alignment was associated with an increasing percentage of good or excellent OKS outcomes, but otherwise there were no significant differences between alignment groups in patient-reported outcome or revision rate. These data support the standard operative technique for the Oxford UKR, which aims to restore ligament tension and therefore prearthritic alignment rather than neutral mechanical alignment. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/estadística & datos numéricos , Prótesis de la Rodilla/estadística & datos numéricos , Anciano , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/mortalidad , Desviación Ósea/mortalidad , Desviación Ósea/cirugía , Femenino , Humanos , Masculino , Osteoartritis de la Rodilla/mortalidad , Osteoartritis de la Rodilla/cirugía , Osteonecrosis/cirugía , Medición de Resultados Informados por el Paciente , Estudios Prospectivos , Reoperación/estadística & datos numéricos , Resultado del Tratamiento
14.
Med Phys ; 35(1): 291-300, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18293584

RESUMEN

Management of respiratory motion during radiation therapy requires treatment planning and simulation using imaging modalities that possess sufficient spatio-temporal accuracy and precision. An investigation into the use of a novel ultrasound (US) imaging system for assessment of respiratory motion is presented, exploiting its good soft tissue contrast and temporal precision. The system dynamically superimposes the appropriate image plane sampled from a reference CT data set with the corresponding US B-mode image. An articulating arm is used for spatial registration. While the focus of the study was to quantify the system's ability to track respiratory motion, certain unique spatial calibration procedures were devised that render the software potentially valuable to the general research community. These include direct access to all transformation matrix elements and image scaling factors, a manual latency correction function, and a three-point spatial registration procedure that allows the system to be used in any room possessing a traditional radiotherapy laser localization system. Counter-intuitively, it was discovered that a manual procedure for calibrating certain transformation matrix elements produced superior accuracy to that of an algorithmic Levenberg-Marquardt optimization method. The absolute spatial accuracy was verified by comparing the physical locations of phantom test objects measured using the spatially registered US system, and using data from a 3DCT scan of the phantom as a reference. The spatial accuracy of the display superposition was also tested in a similar manner. The system's dynamic properties were then assessed using three methods. First, the overall system response time was studied using a programmable motion phantom. This included US video update, articulating arm update, CT data set resampling, and image display. The next investigation verified the system's ability to measure the range of motion of a moving anatomical test phantom that possessed both high and low contrast test objects. Finally, the system's performance was compared to that of a four-dimensional CT (4DCT) data set. The absolute spatial and display superposition accuracy was found to be better than 2 mm and typically 1 mm. Overall dynamic system response was adequate to produce a mean relative positional error of less than 1 mm if an empiric latency correction of 3 video frames was incorporated. The dynamic CT/US display mode was able to assess phantom motion for both high and low contrast test objects to within 1 mm, and compared favorably to the 4DCT data. The 4DCT movie loop accurately assessed the target motion for both of the high and low contrast objects tested, but the minimum intensity and average intensity reconstructions did not. This investigation demonstrated that this US system possesses sufficient spatio-temporal accuracy to properly assess respiratory motion. Future work will seek to demonstrate efficacy in its clinical application to respiratory motion assessment, particularly for sites in the upper abdomen, where low tissue contrast is evident.


Asunto(s)
Benchmarking , Movimiento , Radioterapia , Respiración , Tomografía Computarizada por Rayos X/normas , Ultrasonografía/normas , Algoritmos , Artefactos , Calibración , Humanos , Masculino , Fantasmas de Imagen , Próstata/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía/métodos , Vejiga Urinaria/diagnóstico por imagen , Interfaz Usuario-Computador
15.
Vet Parasitol ; 154(3-4): 193-204, 2008 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-18495349

RESUMEN

The application of attenuated vaccines for the prevention of chicken coccidiosis has increased exponentially in recent years. In Eimeria infections, protective immunity is thought to rely on a strong cell mediated response with antibodies supposedly playing a minor role. However, under certain conditions antibodies seem to be significant in protection. Furthermore, antibodies could be useful for monitoring natural exposure of flocks to Eimeria spp. and for monitoring the infectivity of live vaccines. Our objective was to investigate the chicken antibody response to the different parasite life cycle stages following infection with an attenuated strain of Eimeria tenella. Western blotting analysis of parasite antigens prepared from the lining of caeca infected with the attenuated strain of E. tenella revealed two dominant antigens of 32 and 34 kDa, apparently associated with trophozoites and merozoites that were present at high concentrations between 84 and 132 h post-infection. When cryosections of caeca infected with E. tenella were probed with IgY purified from immune birds the most intense reaction was observed with the asexual stages. Western blotting analysis of proteins of purified sporozoites and third generation merozoites and absorption of stage-specific antibodies from sera suggested that a large proportion of antigens is shared by the two stages. The time-courses of the antibody response to sporozoite and merozoite antigens were similar but varied depending on the inoculation regime and the degree of oocyst recirculation.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Pollos/sangre , Pollos/inmunología , Eimeria tenella/fisiología , Animales , Ciego/parasitología , Cloaca/inmunología , Coccidiosis/parasitología , Coccidiosis/veterinaria , Eimeria tenella/genética , Perfilación de la Expresión Génica , Inmunoglobulinas/sangre , Factores de Tiempo
16.
Ir Med J ; 101(4): 123-4, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18557517

RESUMEN

Some members of the Non-Tuberculous Mycobacteria family are free living organisms in the environment. They may be pathogenic in the immunocomprimised or in chronic lung disease. We describe a case of a nine year old of Asian descent who presented with clinical mastoiditis where the pathogenic organism was Mycobacterium Gordonae. The decision was made to give the patient full antimycobacterial treatment and subsequently the patient made a full recovery.


Asunto(s)
Mastoiditis/microbiología , Micobacterias no Tuberculosas/aislamiento & purificación , Antibióticos Antituberculosos/uso terapéutico , Antituberculosos/uso terapéutico , Niño , Etambutol/uso terapéutico , Femenino , Humanos , Irlanda , Isoniazida/uso terapéutico , Mastoiditis/diagnóstico , Mastoiditis/tratamiento farmacológico , Pirazinamida/uso terapéutico , Rifampin/uso terapéutico
17.
Vet Parasitol ; 150(4): 306-13, 2007 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-17976915

RESUMEN

The aim of this study was to develop and validate an ELISA for detecting chicken antibodies to Eimeria tenella. An initial comparison of merozoite and sporozoite antigen preparations revealed few differences in their ability to monitor the onset, kinetics and magnitude of the antibody response suggesting that both antigens would be equally useful for development of an ELISA. Furthermore the cross-reactivity of these antigens with sera from birds infected with chicken Eimeria species was similar. The merozoite antigen was selected for further evaluation because it was easier to prepare. Discrimination between sera from birds experimentally infected with E. tenella and birds maintained in an Eimeria-free isolation facility was excellent. In sera collected from free-range layers and commercial broilers there also appeared to be clear discrimination between infected and uninfected birds. The ELISA should prove useful for monitoring infectivity in vaccination programmes in layer and breeder flocks and for assessing the effectiveness of biosecurity measures in broiler flocks.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Pollos , Coccidiosis/veterinaria , Eimeria tenella/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de las Aves de Corral/diagnóstico , Animales , Antígenos de Protozoos/inmunología , Coccidiosis/diagnóstico , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Especificidad de la Especie
18.
Mol Biol Cell ; 6(11): 1433-41, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8589447

RESUMEN

To identify proteins that interact in vivo with muscle components we have used a genetic approach based on the isolation of suppressors of mutant alleles of known muscle components. We have applied this system to the case of troponin I (TnI) in Drosophila and its mutant allele heldup2 (hdp2). This mutation causes an alanine to valine substitution at position 116 after a single nucleotide change in a constitutive exon. Among the isolated suppressors, one of them results from a second site mutation at the TnI gene itself. Muscles endowed with TnI mutated at both sites support nearly normal myofibrillar structure, perform notably well in wing beating and flight tests, and isolated muscle fibers produce active force. We show that the structural and functional recovery in this suppressor does not result from a change in the stoichiometric ratio of TnI isoforms. The second site suppression is due to a leucine to phenylalanine change within a heptameric leucine string motif adjacent to the actin binding domain of TnI. These data evidence a structural and functional role for the heptameric leucine string that is most noticeable, if not specific, in the indirect flight muscle.


Asunto(s)
Drosophila/fisiología , Genes de Insecto , Mutación Puntual , Troponina/biosíntesis , Troponina/genética , Alelos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cartilla de ADN , Drosophila/genética , Femenino , Vuelo Animal , Masculino , Microscopía Electrónica , Datos de Secuencia Molecular , Músculos/fisiología , Músculos/ultraestructura , Mutagénesis Sitio-Dirigida , Miofibrillas/fisiología , Miofibrillas/ultraestructura , Fenotipo , Reacción en Cadena de la Polimerasa , Supresión Genética , Troponina I
19.
Poult Sci ; 86(9): 1910-4, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17704378

RESUMEN

Immunoglobulin Y is different from most of the other immunoglobulins because it does not bind protein A or protein G. Thiophilic gel chromatography has been successfully used to purify IgY from chicken egg yolk, but the technology has not previously been used to purify IgY from serum. In this research note, we describe the optimization of T-gel chromatography for purification of IgY from serum. Data are provided on the recovery and purity of IgY obtained using potassium sulfate buffers of different concentrations. Decreasing the strength of potassium sulfate buffer from 0.5 to 0.3 M did not alter the amount of IgY recovered but increased the purity. Using 0.3 M potassium sulphate, we recovered approximately 63.7% of the serum Ig as almost pure IgY.


Asunto(s)
Pollos/sangre , Cromatografía en Gel/veterinaria , Inmunoglobulinas/sangre , Inmunoglobulinas/aislamiento & purificación , Animales , Sulfatos
20.
Chem Commun (Camb) ; 53(3): 605-608, 2017 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-27981325

RESUMEN

The reversible oxidation of coordinated phenolates into phenoxyl radicals results in a dramatic quenching (>95%) of the luminescence of the f metal ion.


Asunto(s)
Elementos de la Serie de los Lantanoides/química , Luminiscencia , Fenoles/química , Oxidación-Reducción
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