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1.
Pediatr Allergy Immunol ; 27 Suppl 23: 1-250, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27288833

RESUMEN

The availability of allergen molecules ('components') from several protein families has advanced our understanding of immunoglobulin E (IgE)-mediated responses and enabled 'component-resolved diagnosis' (CRD). The European Academy of Allergy and Clinical Immunology (EAACI) Molecular Allergology User's Guide (MAUG) provides comprehensive information on important allergens and describes the diagnostic options using CRD. Part A of the EAACI MAUG introduces allergen molecules, families, composition of extracts, databases, and diagnostic IgE, skin, and basophil tests. Singleplex and multiplex IgE assays with components improve both sensitivity for low-abundance allergens and analytical specificity; IgE to individual allergens can yield information on clinical risks and distinguish cross-reactivity from true primary sensitization. Part B discusses the clinical and molecular aspects of IgE-mediated allergies to foods (including nuts, seeds, legumes, fruits, vegetables, cereal grains, milk, egg, meat, fish, and shellfish), inhalants (pollen, mold spores, mites, and animal dander), and Hymenoptera venom. Diagnostic algorithms and short case histories provide useful information for the clinical workup of allergic individuals targeted for CRD. Part C covers protein families containing ubiquitous, highly cross-reactive panallergens from plant (lipid transfer proteins, polcalcins, PR-10, profilins) and animal sources (lipocalins, parvalbumins, serum albumins, tropomyosins) and explains their diagnostic and clinical utility. Part D lists 100 important allergen molecules. In conclusion, IgE-mediated reactions and allergic diseases, including allergic rhinoconjunctivitis, asthma, food reactions, and insect sting reactions, are discussed from a novel molecular perspective. The EAACI MAUG documents the rapid progression of molecular allergology from basic research to its integration into clinical practice, a quantum leap in the management of allergic patients.


Asunto(s)
Alérgenos/inmunología , Hipersensibilidad Inmediata/diagnóstico , Inmunoglobulina E/metabolismo , Biomarcadores/metabolismo , Humanos , Hipersensibilidad Inmediata/inmunología , Hipersensibilidad Inmediata/metabolismo , Hipersensibilidad Inmediata/terapia , Pruebas Inmunológicas/métodos , Medicina de Precisión/métodos
2.
Allergy ; 70(4): 420-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25556717

RESUMEN

BACKGROUND: Despite the critical role of immunoglobulin E (IgE) in allergy, circulating IgE+ B cells are scarce. Here, we describe in patients with allergic rhinitis B cells with a memory phenotype responding to a prototypic aeroallergen. METHODS: Fifteen allergic rhinitis patients with grass pollen allergy and 13 control subjects were examined. Blood mononuclear cells stained with carboxyfluorescein diacetate succinimidyl ester (CFSE) were cultured with Bahia grass pollen. Proliferation and phenotype were assessed by multicolour flow cytometry. RESULTS: In blood of allergic rhinitis patients with high serum IgE to grass pollen, most IgE(hi) cells were CD123+ HLA-DR(-) basophils, with IgE for the major pollen allergen (Pas n 1). Both B and T cells from pollen-allergic donors showed higher proliferation to grass pollen than nonallergic donors (P = 0.002, and 0.010, respectively), whereas responses to vaccine antigens and mitogen did not differ between groups. Allergen-driven B cells that divided rapidly (CD19(mid) CD3(-) CFSE(lo) ) showed higher CD27 (P = 0.008) and lower CD19 (P = 0.004) and CD20 (P = 0.004) expression than B cells that were slow to respond to allergen (CD19(hi) CD3(-) CFSE(mid) ). Moreover, rapidly dividing allergen-driven B cells (CD19(mid) CFSE(lo) CD27(hi) ) showed higher expression of the plasmablast marker CD38 compared with B cells (CD19(hi) CFSE(mid) CD27(lo) ) that were slow to divide. CONCLUSION: Patients with pollen allergy but not control donors have a population of circulating allergen-specific B cells with the phenotype and functional properties of adaptive memory B-cell responses. These cells could provide precursors for allergen-specific IgE production upon allergen re-exposure.


Asunto(s)
Alérgenos/inmunología , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Inmunoglobulina E/inmunología , Memoria Inmunológica , Rinitis Alérgica/inmunología , Rinitis Alérgica/metabolismo , Adulto , Alérgenos/metabolismo , Estudios de Casos y Controles , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/metabolismo , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Fenotipo , Poaceae/efectos adversos , Polen/inmunología , Unión Proteica/inmunología , Rinitis Alérgica/diagnóstico , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica Estacional/metabolismo , Adulto Joven
3.
Clin Exp Allergy ; 44(6): 790-801, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24684550

RESUMEN

Grass pollens of the temperate (Pooideae) subfamily and subtropical subfamilies of grasses are major aeroallergen sources worldwide. The subtropical Chloridoideae (e.g. Cynodon dactylon; Bermuda grass) and Panicoideae (e.g. Paspalum notatum; Bahia grass) species are abundant in parts of Africa, India, Asia, Australia and the Americas, where a large and increasing proportion of the world's population abide. These grasses are phylogenetically and ecologically distinct from temperate grasses. With the advent of global warming, it is conceivable that the geographic distribution of subtropical grasses and the contribution of their pollen to the burden of allergic rhinitis and asthma will increase. This review aims to provide a comprehensive synthesis of the current global knowledge of (i) regional variation in allergic sensitivity to subtropical grass pollens, (ii) molecular allergenic components of subtropical grass pollens and (iii) allergic responses to subtropical grass pollen allergens in relevant populations. Patients from subtropical regions of the world show higher allergic sensitivity to grass pollens of Chloridoideae and Panicoideae grasses, than to temperate grass pollens. The group 1 allergens are amongst the allergen components of subtropical grass pollens, but the group 5 allergens, by which temperate grass pollen extracts are standardized for allergen content, appear to be absent from both subfamilies of subtropical grasses. Whilst there are shared allergenic components and antigenic determinants, there are additional clinically relevant subfamily-specific differences, at T- and B-cell levels, between pollen allergens of subtropical and temperate grasses. Differential immune recognition of subtropical grass pollens is likely to impact upon the efficacy of allergen immunotherapy of patients who are primarily sensitized to subtropical grass pollens. The literature reviewed herein highlights the clinical need to standardize allergen preparations for both types of subtropical grass pollens to achieve optimal diagnosis and treatment of patients with allergic respiratory disease in subtropical regions of the world.


Asunto(s)
Alérgenos/inmunología , Poaceae/efectos adversos , Polen/inmunología , Hipersensibilidad Respiratoria/inmunología , Reacciones Cruzadas/inmunología , Salud Global , Humanos , Poaceae/clasificación , Poaceae/genética , Hipersensibilidad Respiratoria/epidemiología , Clima Tropical
4.
Sci Total Environ ; 862: 160585, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502990

RESUMEN

eDNA metabarcoding is an emergent tool to inform aerobiome complexity, but few studies have applied this technology with real-world environmental pollen monitoring samples. Here we apply eDNA metabarcoding to assess seasonal and regional differences in the composition of airborne pollen from routine samples collected across successive years. Airborne pollen concentrations over two sampling periods were determined using a continuous flow volumetric impaction air sampler in sub-tropical (Mutdapilly and Rocklea) and temperate (Macquarie Park and Richmond), sites of Australia. eDNA metabarcoding was applied to daily pollen samples collected once per week using the rbcL amplicon. Composition and redundancy analysis of the sequence read counts were examined. The dominant pollen families were mostly consistent between consecutive years but there was some heterogeneity between sites and years for month of peak pollen release. Many more families were detected by eDNA than counted by light microscopy with 211 to 399 operational taxonomic units assigned to family per site from October to May. There were 216 unique and 119 taxa shared between subtropics (27°S) and temperate (33°S) latitudes, with, for example, Poaceae, Myrtaceae and Causurinaceae being shared, and Manihot, Vigna and Aristida being in subtropical, and Ceratodon and Cerastium being in temperate sites. Certain genera were observed within the same location and season over the two years; Chloris at Rocklea in autumn of 2017-18 (0.625, p ≤ 0.004) and 2018-19 (0.55, p ≤ 0.001), and Pinus and Plantago at Macquarie Park in summer of 2017-18 (0.58, p ≤ 0.001 and 0.53, p ≤ 0.003, respectively), and 2018-19 (0.8, p ≤ 0.003 and 0.8, p ≤ 0.003, respectively). eDNA metabarcoding is a powerful tool to survey the complexity of pollen aerobiology and distinguish spatial and temporal profiles of local pollen to a far deeper level than traditional counting methods. However, further research is required to optimise the metabarcode target to enable reliable detection of pollen to genus and species level.


Asunto(s)
Biodiversidad , Código de Barras del ADN Taxonómico , Monitoreo del Ambiente , Polen , Australia , ADN Ambiental , Monitoreo del Ambiente/métodos , Poaceae , Polen/clasificación , Polen/genética
5.
Plant Biol (Stuttg) ; 24(5): 863-873, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35395136

RESUMEN

Extracellular ATP (eATP) increases cytosolic free calcium ([Ca2+ ]cyt ) as a specific second messenger 'signature' through the plasma membrane DORN1/P2K1 receptor. Previous studies revealed a biphasic signature in Arabidopsis thaliana roots that is altered by inorganic phosphate (Pi) deprivation. The relationship between the two phases of the signature and possible wave formation have been tested as a function of Pi nutrition. The bioluminescent aequorin and intensiometric GCaMP3 reporters were used to resolve the spatial origin of the eATP [Ca2+ ]cyt signature in Arabidopsis root tips. Application of eATP only to the root apex allowed [Ca2+ ]cyt wave resolution without the confounding effects of eATP delivery by superfusion. The first apical millimetre of the root generates the first [Ca2+ ]cyt increase by eATP, regardless of nutritional status. The second increase occurs sub-apically in the root hair zone, has some autonomy and is significantly reduced in Pi-starved roots. A significant component of the Pi-replete signature does not require DORN1/P2K1, but Pi-starved roots appear to have an absolute requirement for that receptor. Application of eATP specifically to the root apex provides evidence for cell-to-cell propagation of a [Ca2+ ]cyt wave that diminishes sub-apically. The apex maintains a robust [Ca2+ ]cyt increase (even under Pi starvation) that is the basis of a propagative wave, with implications for the ability of the root's eATP signalling systems to signal systemically. Partial autonomy of the sub-apical region may be relevant to the perception of eATP from microbes. eATP-induced [Ca2+ ]cyt increase may not have always have an obligate requirement for DORN1/P2K1.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Adenosina Trifosfato , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Calcio/metabolismo , Señalización del Calcio , Estado Nutricional , Fosfatos/metabolismo , Raíces de Plantas/metabolismo
6.
Br J Cancer ; 104(7): 1067-70, 2011 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-21386841

RESUMEN

BACKGROUND: This study sought to determine the safety of single agent capecitabine, a pro-drug of 5FU, in patients with metastatic non-pancreatic neuroendocrine tumours (NETs). METHODS: Multicentre phase II, first-line study design. Oral capecitabine was administered on days 1-14 of 3-week cycles. RESULTS: Treatment was safe and well tolerated. Common toxicities were diarrhoea and fatigue. CONCLUSION: The study provides evidence to support the use of capecitabine as a substitute for infusional 5FU in the management of NETs.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Desoxicitidina/análogos & derivados , Fluorouracilo/análogos & derivados , Tumores Neuroendocrinos/tratamiento farmacológico , Anciano , Capecitabina , Desoxicitidina/efectos adversos , Desoxicitidina/uso terapéutico , Femenino , Fluorouracilo/efectos adversos , Fluorouracilo/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia/tratamiento farmacológico
7.
Clin Exp Allergy ; 41(2): 281-91, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21231976

RESUMEN

BACKGROUND: Grass pollens are major triggers of allergic rhinitis and asthma, but the immunological relationships between pollen allergens of the subtropical Bahia grass, Paspalum notatum, and temperate grasses are unresolved. OBJECTIVE: To assess serum IgE cross-reactivity between subtropical P. notatum and temperate Lolium perenne (Ryegrass) pollen allergens. METHODS: Serum IgE reactivities of grass pollen-allergic patients with P. notatum, L. perenne and Cynodon dactylon (Bermuda grass) pollen extracts and their respective purified group 1 allergens, Pas n 1, Lol p 1 and Cyn d 1, were compared by immunoblotting, ELISA and basophil activation. RESULTS: In a cohort of 51 patients from a temperate region, a high frequency of IgE reactivity with each grass pollen was detected, but reactivity with L. perenne pollen was substantially greater than with P. notatum and C. dactylon pollen. Similarly, serum IgE reactivity with Lol p 1 was greater than with Pas n 1 or Cyn d 1. For seven of eight sera studied in detail, asymmetric serum IgE cross-reactivity was observed; L. perenne pollen inhibited IgE reactivity with P. notatum pollen but not the converse, and IgE reactivity with Pas n 1 was inhibited by Lol p 1 but IgE reactivity with Lol p 1 was not inhibited by Pas n 1 or Cyn d 1. Importantly, P. notatum pollen and Pas n 1 activated basophils in grass pollen-allergic patients from a temperate region, although stimulation was greater by pollen of L. perenne than P. notatum or C. dactylon, and by Lol p 1 than Pas n 1 or Cyn d 1. In contrast, a cohort of 47 patients from a subtropical region showed similar IgE reactivity with P. notatum and L. perenne pollen, and reciprocal cross-inhibition of IgE reactivity between L. perenne and P. notatum. CONCLUSIONS: Pollen allergens of the subtropical P. notatum, including Pas n 1, show clinically relevant IgE cross-reactivity with pollen allergens of L. perenne but also species-specific IgE reactivity.


Asunto(s)
Alérgenos/inmunología , Inmunoglobulina E/inmunología , Polen/inmunología , Rinitis Alérgica Estacional/inmunología , Alérgenos/genética , Reacciones Cruzadas/inmunología , Cynodon/inmunología , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/genética , Lolium/inmunología , Penicillium/inmunología
8.
AJNR Am J Neuroradiol ; 42(1): 57-64, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33243895

RESUMEN

BACKGROUND AND PURPOSE: Clot perviousness in acute ischemic stroke is a potential CT imaging biomarker for mechanical thrombectomy efficacy. We investigated the association among perviousness, clot cellular composition, and first-pass effect. MATERIALS AND METHODS: In 40 mechanical thrombectomy-treated cases of acute ischemic stroke, we calculated perviousness as the difference in clot density on CT angiography and noncontrast CT. We assessed the proportion of fibrin/platelet aggregates, red blood cells, and white blood cells on clot histopathology. We tested for linear correlation between histologic components and perviousness, differences in components between "high" and "low" pervious clots defined by median perviousness, and differences in perviousness/composition between cases that did and did not achieve a first-pass effect. RESULTS: Perviousness significantly positively and negatively correlated with the percentage of fibrin/platelet aggregates (P = .001) and the percentage of red blood cells (P = .001), respectively. Higher pervious clots had significantly greater fibrin/platelet aggregate content (P = .042). Cases that achieved a first-pass effect (n = 14) had lower perviousness, though not significantly (P = .055). The percentage of red blood cells was significantly higher (P = .028) and the percentage of fibrin/platelet aggregates was significantly lower (P = .016) in cases with a first-pass effect. There was no association between clot density on NCCT and clot composition or first-pass effect. Receiver operating characteristic analysis indicated that clot composition was the best predictor of first-pass effect (area under receiver operating characteristic curve: percentage of fibrin/platelet aggregates = 0.731, percentage of red blood cells = 0.706, perviousness = 0.668). CONCLUSIONS: Clot perviousness on CT is associated with a higher percentage of fibrin/platelet aggregate content. Histologic data and, to a lesser degree, perviousness may have value in predicting first-pass outcome. Imaging metrics that more strongly reflect clot biology than perviousness may be needed to predict a first-pass effect with high accuracy.


Asunto(s)
Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/cirugía , Trombosis/diagnóstico por imagen , Resultado del Tratamiento , Anciano , Plaquetas/patología , Angiografía por Tomografía Computarizada/métodos , Femenino , Fibrina/análisis , Humanos , Accidente Cerebrovascular Isquémico/patología , Masculino , Trombectomía/métodos , Trombosis/patología
9.
Sci Total Environ ; 747: 141189, 2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-32799020

RESUMEN

The importance of grass pollen to the global burden of allergic respiratory disease is well established but exposure to subtropical and temperate pollens is difficult to discern. Current monitoring of airborne pollen relies on light microscopy, limiting identification of taxa to family level. This informs seasonal fluctuations in pollen aerobiology but restricts analysis of aerobiological composition. We aimed to test the utility of DNA metabarcoding to identify specific taxa contributing to the aerobiome of environmental air samples, using routine pollen and spore monitoring equipment, as well as assess temporal variation of Poaceae pollen across an entire season. Airborne pollen concentrations were determined by light microscopy over two pollen seasons in the subtropical city of Brisbane (27°32'S, 153°00E), Australia. Thirty daily pollen samples were subjected to high throughput sequencing of the plastid rbcL amplicon. Amplicons corresponded to plants observed in the local biogeographical region with up to 3238 different operational taxonomic units (OTU) detected. The aerobiome sequencing data frequently identified pollen to genus levels with significant quantitative differences in aerobiome diversity between the months and seasons detected. Moreover, multiple peaks of Chloridoideae and Panicoideae pollen were evident over the collection period confirming these grasses as the dominant Poaceae pollen source across the season. Targeted high throughput sequencing of routinely collected airborne pollen samples appears to offer utility to track temporal changes in the aerobiome and shifts in pollen exposure. Precise identification of the composition and temporal distributions of airborne pollen is important for tracking biodiversity and for management of allergic respiratory disease.


Asunto(s)
Poaceae , Polen , Alérgenos , Australia , Ciudades , Estaciones del Año
10.
AJNR Am J Neuroradiol ; 41(2): 206-212, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31948951

RESUMEN

BACKGROUND AND PURPOSE: Brain CTP is used to estimate infarct and penumbra volumes to determine endovascular treatment eligibility for patients with acute ischemic stroke. We aimed to assess the accuracy of a Bayesian CTP algorithm in determining penumbra and final infarct volumes. MATERIALS AND METHODS: Data were retrospectively collected for 105 patients with acute ischemic stroke (55 patients with successful recanalization [TICI 2b/2c/3] and large-vessel occlusions and 50 patients without interventions). Final infarct volumes were calculated using DWI and FLAIR 24 hours following CTP imaging. RAPID and the Vitrea Bayesian CTP algorithm (with 3 different settings) predicted infarct and penumbra volumes for comparison with final infarct volumes to assess software performance. Vitrea settings used different combinations of perfusion maps (MTT, TTP, CBV, CBF, delay time) for infarct and penumbra quantification. Patients with and without interventions were included for assessment of predicted infarct and penumbra volumes, respectively. RESULTS: RAPID and Vitrea default setting had the most accurate final infarct volume prediction in patients with interventions ([Spearman correlation coefficient, mean infarct difference] default versus FLAIR: [0.77, 4.1 mL], default versus DWI: [0.72, 4.7 mL], RAPID versus FLAIR: [0.75, 7.5 mL], RAPID versus DWI: [0.75, 6.9 mL]). Default Vitrea and RAPID were the most and least accurate in determining final infarct volume for patients without an intervention, respectively (default versus FLAIR: [0.76, -0.4 mL], default versus DWI: [0.71, -2.6 mL], RAPID versus FLAIR: [0.68, -49.3 mL], RAPID versus DWI: [0.65, -51.5 mL]). CONCLUSIONS: Compared with RAPID, the Vitrea default setting was noninferior for patients with interventions and superior in penumbra estimation for patients without interventions as indicated by mean infarct differences and correlations with final infarct volumes.


Asunto(s)
Algoritmos , Interpretación de Imagen Asistida por Computador/métodos , Neuroimagen/métodos , Imagen de Perfusión/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Teorema de Bayes , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/patología , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Accidente Cerebrovascular/patología , Tomografía Computarizada por Rayos X/métodos
11.
Science ; 232(4752): 865-7, 1986 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-17755970

RESUMEN

Recent determinations of high production rates (up to 30 percent of primary production in surface waters) implicate free-living marine bacterioplankton as a link in a "microbial loop" that supplements phytoplankton as food for herbivores. An enclosed water column of 300 cubic meters was used to test the microbial loop hypothesis by following the fate of carbon-14-labeled bacterioplankton for over 50 days. Only 2 percent of the label initially fixed from carbon-14-labeled glucose by bacteria was present in larger organisms after 13 days, at which time about 20 percent of the total label added remained in the particulate fraction. Most of the label appeared to pass directly from particles smaller than 1 micrometer (heterotrophic bacterioplankton and some bacteriovores) to respired labeled carbon dioxide or to regenerated dissolved organic carbon-14. Secondary (and, by implication, primary) production by organisms smaller than 1 micrometer may not be an important food source in marine food chains. Bacterioplankton can be a sink for carbon in planktonic food webs and may serve principally as agents of nutrient regeneration rather than as food.

12.
Trends Biochem Sci ; 17(9): 348-53, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1329278

RESUMEN

The membrane surrounding the central vacuole of plant cells contains an H(+)-translocating ATPase (H(+)-ATPase) and an H(+)-translocating inorganic pyrophosphatase (H(+)-PPase). Both enzymes are abundant and ubiquitous in plants but the H(+)-PPase is unusual in its exclusive use of inorganic pyrophosphate (PPi) as an energy source. The lack of sequence identity between the vacuolar H(+)-PPase and any other characterized ion pump implies a different evolutionary origin for this translocase. The existence of the vacuolar H(+)-PPase, in conjunction with increasing recognition of PPi as a key metabolite in plant systems, necessitates reconsideration of ATP as the primary energy source for membrane transport in plant cells.


Asunto(s)
Difosfatos/metabolismo , Bombas de Protones , Vacuolas/metabolismo , Secuencia de Aminoácidos , Transporte Biológico , Membrana Celular/metabolismo , Datos de Secuencia Molecular , Plantas/metabolismo , ATPasas de Translocación de Protón
13.
AJNR Am J Neuroradiol ; 40(11): 1939-1946, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31649161

RESUMEN

BACKGROUND AND PURPOSE: In patients with SAH with multiple intracranial aneurysms, often the hemorrhage pattern does not indicate the rupture source. Angiographic findings (intracranial aneurysm size and shape) could help but may not be reliable. Our purpose was to test whether existing parameters could identify the ruptured intracranial aneurysm in patients with multiple intracranial aneurysms and whether composite predictive models could improve the identification. MATERIALS AND METHODS: We retrospectively collected angiographic and medical records of 93 patients with SAH with at least 2 intracranial aneurysms (total of 206 saccular intracranial aneurysms, 93 ruptured), in which the ruptured intracranial aneurysm was confirmed through surgery or definitive hemorrhage patterns. We calculated 13 morphologic and 10 hemodynamic parameters along with location and type (sidewall/bifurcation) and tested their ability to identify rupture in the 93 patients. To build predictive models, we randomly assigned 70 patients to training and 23 to holdout testing cohorts. Using a linear regression model with a customized cost function and 10-fold cross-validation, we trained 2 rupture identification models: RIMC using all parameters and RIMM excluding hemodynamics. RESULTS: The 25 study parameters had vastly different positive predictive values (31%-87%) for identifying rupture, the highest being size ratio at 87%. RIMC incorporated size ratio, undulation index, relative residence time, and type; RIMM had only size ratio, undulation index, and type. During cross-validation, positive predictive values for size ratio, RIMM, and RIMC were 86% ± 4%, 90% ± 4%, and 93% ± 4%, respectively. In testing, size ratio and RIMM had positive predictive values of 85%, while RIMC had 92%. CONCLUSIONS: Size ratio was the best individual factor for identifying the ruptured aneurysm; however, RIMC, followed by RIMM, outperformed existing parameters.


Asunto(s)
Aneurisma Roto/complicaciones , Aneurisma Roto/diagnóstico por imagen , Hemodinámica , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico por imagen , Hemorragia Subaracnoidea/etiología , Anciano , Algoritmos , Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional , Modelos Lineales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
14.
AJNR Am J Neuroradiol ; 40(7): 1197-1200, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31171521

RESUMEN

Traditional digital subtraction angiography provides rather limited evaluation of contrast flow dynamics when studying and treating intracranial brain aneurysms. A 1000-frames-per-second photon-counting x-ray detector was used to image detailed iodine-contrast flow patterns in an internal carotid artery aneurysm of a 3D-printed vascular phantom. High-speed imaging revealed differences in vortex and inflow patterns with and without a Pipeline Embolization Device flow diverter in more detail and clarity than could be seen in standard pulsed angiography. Improved temporal imaging has the potential to impact the outcomes of endovascular interventions by allowing clinicians to better understand and act on flow dynamics in real-time.


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Modelos Neurológicos , Neuroimagen/métodos , Prótesis Vascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fantasmas de Imagen
15.
AJNR Am J Neuroradiol ; 40(2): 288-294, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30679216

RESUMEN

BACKGROUND AND PURPOSE: Incompletely occluded flow diverter treated aneurysms remain at risk of rupture and thromboembolic complications. Our aim was to identify the potential for incomplete occlusion of intracranial aneurysms treated by flow diverters. We investigated whether aneurysm ostium size in relation to parent artery size affects angiographic outcomes of flow diverter-treated sidewall aneurysms. MATERIALS AND METHODS: Flow diverter-treated sidewall aneurysms were divided into "occluded" and "residual" (incomplete occlusion) groups based on 6-month angiographic follow-up. We calculated the ostium ratio, a new parameter defined as the aneurysm ostium surface area versus the circumferential surface area of the parent artery. We also calculated the neck ratio, defined as clinical aneurysm neck diameter versus parent artery diameter from pretreatment 2D DSA, as a 2D surrogate. We compared the performance of these ratios with existing aneurysm morphometrics (size, neck diameter, volume, aspect ratio, size ratio, undulation index, nonsphericity index, ellipticity index, bottleneck factor, aneurysm angle, and parent vessel angle) and flow diverter-related parameters (metal coverage rate and pore density). Statistical tests and receiver operating characteristic analyses were performed to identify significantly different parameters between the 2 groups and test their predictive performances. RESULTS: We included 63 flow diverter-treated aneurysms, 46 occluded and 17 residual. The ostium ratio and neck ratio were significantly higher in the residual group than in the occluded group (P < .001 and P = .02, respectively), whereas all other parameters showed no statistical difference. As discriminating parameters for occlusion, ostium ratio and neck ratio achieved areas under the curve of 0.912 (95% CI, 0.838-0.985) and 0.707 (95% CI, 0.558-0.856), respectively. CONCLUSIONS: High ostium ratios and neck ratios could predict incomplete occlusion of flow diverter-treated sidewall aneurysms. Neck ratio can be easily calculated by interventionists to predict flow-diverter treatment outcomes.


Asunto(s)
Aneurisma Intracraneal/patología , Aneurisma Intracraneal/terapia , Stents , Resultado del Tratamiento , Anciano , Algoritmos , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Clin Exp Allergy ; 38(4): 566-78, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18261159

RESUMEN

Patients with allergic diseases produce an excess of allergen-specific IgE, the specific effector molecule that triggers allergic reactions. The provocation for this excess IgE production is still uncertain. Current ideas include oligoclonal expansion of allergen-specific B cells emanating from germinal centres, activation by superantigen of a subset of B cells, or polyclonal B cells class switching to IgE due to an IL-4 predominance. Additionally, genetic elements contribute to a propensity for increased allergen-specific IgE production. The procedure of RT-PCR allows for amplification of infrequent IgE mRNA transcripts from B cells of atopic individuals, and so facilitates examination of expressed Ig cDNA sequences. Better knowledge of the molecular characteristics of IgE produced by patients with allergic diseases would elucidate the immunogenetic basis for elevated allergen-specific IgE levels. The 'immunogenetic footprint' of IgE transcripts may elucidate the origin and activation of IgE-producing B cells in allergic disease. Here we review studies of the immunogenetic features of IgE in allergic diseases, highlighting the major advances and the experimental limitations.


Asunto(s)
Hipersensibilidad/genética , Hipersensibilidad/inmunología , Inmunogenética/métodos , Inmunoglobulina E/genética , Anticuerpos/sangre , Reacciones Antígeno-Anticuerpo , Linfocitos B/inmunología , Humanos , Hipersensibilidad/terapia , Inmunoglobulina G/sangre
17.
Plant Cell Environ ; 31(6): 861-71, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18284583

RESUMEN

There is increasing evidence of the important roles of glutamate receptors (GLRs) in plant development and in adaptation to stresses. However, the studies of these putative ion channels, both in planta and in Xenopus oocytes, may have been limited by our lack of knowledge of possible GLR heteromer formation in plants. We have developed a modification of the single-cell sampling technique to investigate GLR co-expression, and thus potential heteromer formation, in single cells of Arabidopsis thaliana leaves. Micro-EXpression amplification (MEX) has allowed us to amplify gene transcripts from a single cell, enabling expression of up to 100 gene transcripts to be assayed. We measured, on average, the transcripts of five to six different AtGLRs in a single cell. However, no consistent patterns of co-expression or cell-type-specific expression were detected, except that cells sampled from the same plant showed similar expression profiles. The only discernible feature was the detection of AtGLR3.7 in every cell examined, an observation supported by GUS staining patterns in plants stably expressing promoter::uidA fusions. In addition, we found AtGLR3.7 expression in oocytes induces a Ba2+-, Ca2+- and Na+-permeable plasma membrane conductance.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Receptores de Glutamato/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Hojas de la Planta/metabolismo , Receptores de Glutamato/genética
19.
Health Sci Rep ; 1(8): e54, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30623090

RESUMEN

BACKGROUND AND AIMS: The prognostic effect of sidedness in colorectal cancer has been evaluated in numerous prospective and retrospective cohorts. Most of these have reported overall survival data; there is scant relapse-free survival data in early stage disease. This study aimed to determine the effect of tumor sidedness in survival in early stage and relapsed colon cancer. METHODS: Patients with stage I-III colorectal cancer were identified from the BC Cancer Agency Gastrointestinal Cancer Outcomes Unit. Survival analysis by stage and sidedness was compared with the log-rank test. Baseline characteristics were controlled by multivariate Cox-proportional hazard models. In relapsed patients, bevacizumab and EGFR inhibitor (EGFRI) treatments were included and tested for interaction. RESULTS: Among 5378 patients with stage I-III colon cancer, patients with right-sided stage II tumors experienced better relapse-free survival compared with those with left-sided tumors; right-sidedness was not prognostic for RFS in stage III disease. When survival was considered in patients who relapsed, right-sided tumors had inferior survival after relapse in both stage II and stage III tumors. At relapse, right-sided outcomes were inferior regardless of biologic therapy. An interaction test revealed a significant association between sidedness and survival with EGFRIs. CONCLUSIONS: In this large, population-based study, right-sided presentation has a significant prognostic impact: in early stage, right-sidedness is favorably prognostic among stage II tumors and not prognostic in stage III disease. After relapse, right- sidedness is associated with an inferior prognosis, regardless of initial stage of presentation. Colon tumor sidedness is independently prognostic and may be considered in treatment assignment for both early stage and advanced disease.

20.
Clin Oncol (R Coll Radiol) ; 29(10): 669-675, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28711306

RESUMEN

Healthcare practitioners have long considered aviation as a domain from which much can be learned about safety. Over the past 30 years, attempts have been made to apply aviation safety-related concepts to healthcare. Although some applications have been successful, a few decades later, many healthcare safety experts have learned that the appeal of the aviation-healthcare analogy is an illusion. Both domains are so basically dissimilar that simple adoption of aviation concepts will not be successful. However, what has succeeded is healthcare's adaptation of specific aviation safety concepts. Three concepts, investment in safety, human factors and safety management systems, are described and examples are given of adapted applications to healthcare/clinical oncology. Finally, there is a need to ensure that these concepts are applied systematically throughout healthcare rather than sporadically and without a centralised mandate, to help ensure success and improved patient and provider safety.


Asunto(s)
Aviación/organización & administración , Oncología Médica/educación , Administración de la Seguridad/métodos , Humanos
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