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1.
Brain Struct Funct ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528269

RESUMEN

Multiple neurocognitive processes are involved in the highly complex task of producing written words. Yet, little is known about the neural pathways that support spelling in healthy adults. We assessed the associations between performance on a difficult spelling-to-dictation task and microstructural properties of language-related white matter pathways, in a sample of 73 native English-speaking neurotypical adults. Participants completed a diffusion magnetic resonance imaging scan and a cognitive assessment battery. Using constrained spherical deconvolution modeling and probabilistic tractography, we reconstructed dorsal and ventral white matter tracts of interest, bilaterally, in individual participants. Spelling associations were found in both dorsal and ventral stream pathways. In high-performing spellers, spelling scores significantly correlated with fractional anisotropy (FA) within the left inferior longitudinal fasciculus, a ventral stream pathway. In low-performing spellers, spelling scores significantly correlated with FA within the third branch of the right superior longitudinal fasciculus, a dorsal pathway. An automated analysis of spelling errors revealed that high- and low- performing spellers also differed in their error patterns, diverging primarily in terms of the orthographic distance between their errors and the correct spelling, compared to the phonological plausibility of their spelling responses. The results demonstrate the complexity of the neurocognitive architecture of spelling. The distinct white matter associations and error patterns detected in low- and high- performing spellers suggest that they rely on different cognitive processes, such that high-performing spellers rely more on lexical-orthographic representations, while low-performing spellers rely more on phoneme-to-grapheme conversion.

2.
Q J Exp Psychol (Hove) ; : 17470218241229442, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38247168

RESUMEN

Theories suggest that efficient recognition of English words depends on flexible letter-position coding, demonstrated by the fact that transposed-letter primes (e.g., JUGDE-judge) facilitate written word recognition more than substituted-letter primes (e.g., JUFBE-judge). The multiple route model predicts that reading experience should drive more flexible letter-position coding as readers transition from decoding words letter-by-letter to recognising words as wholes. This study therefore examined whether letter-position is coded flexibly in second-language English sentence reading for native Chinese speakers, and if this is influenced by English proficiency. Eye movements were measured while 54 adult native Chinese speakers read English sentences including either a real word (e.g., cheaply), a transposed-letter nonword (e.g., "chepaly"), or a substituted-letter nonword (e.g., "chegely"). Flexible letter-position coding was observed in initial and later processing stages-reading times were longer for substituted-letter than transposed-letter nonwords. In addition, reading times were longer in both initial and later processing stages for transposed-letter nonwords than real words, indicating that, despite encoding letter-position flexibly, readers processed letter-position. Although pre-registered frequentist analyses suggested that English proficiency did not predict overall reading times, Bayes Factors indicated that there was evidence for such a relationship. It is therefore likely that this proficiency analysis suffered from low power. Finally, neither frequentist nor Bayes Factor analyses suggested that English proficiency influenced the difference in reading times between different target word types, i.e., the nature of letter-position coding. Overall, these results suggest that highly proficient L2 learners code letter-position flexibly.

3.
J Hosp Infect ; 141: 99-106, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37696471

RESUMEN

BACKGROUND: Percutaneous nephrostomy catheters (PCNs) are commonly utilized in patients with gynaecological cancers due to intrinsic or extrinsic urinary obstruction. Unfortunately, these foreign medical devices may be associated with several infectious complications, including: pyelonephritis, renal abscess, and bacteraemia, which may lead to further delay of life-saving cancer therapy. AIM: To evaluate the performance of our multidisciplinary algorithm for diagnosis and treatment of PCN-related infections (PCNIs) and identify risk factors for recurrent urinary device-related infections. METHODS: Patients with gynaecological cancers having PCNIs were prospectively evaluated at our institution from July 2019 to September 2021. All patients were managed by our standardized algorithm and followed-up until reinfection or routine PCN exchange. FINDINGS: Of 100 consecutive patients with PCNIs, 74 had adequate follow-up, and were analysed in three groups according to clinical outcome: reinfection with the same organism (26%), reinfection with a different organism (23%), and no reinfection (51%). Their median age was 54 years, and the most common cancers were cervical (65%), and ovarian (19%) with 53% being metastatic. The most frequently recovered micro-organisms were Pseudomonas (32%), Enterococcus (27%), and Escherichia (24%) species. The main risk factors for recurrent PCNI with the same organism were pelvic radiation therapy (P=0.032), pelvic fistulas (P=0.014), and a PCNI with the same pathogen within the previous year (P = 0.012). CONCLUSIONS: Our algorithm has allowed for accurate diagnosis, staging, and treatment of and identification of several key risk factors for recurrent PCNIs. These results may lead to further preventive measures for these infections.


Asunto(s)
Infecciones Relacionadas con Catéteres , Neoplasias , Nefrostomía Percutánea , Infecciones Urinarias , Humanos , Persona de Mediana Edad , Nefrostomía Percutánea/efectos adversos , Nefrostomía Percutánea/métodos , Infecciones Relacionadas con Catéteres/complicaciones , Reinfección/complicaciones , Neoplasias/complicaciones , Pacientes , Infecciones Urinarias/etiología , Estudios Retrospectivos
4.
Dev Psychol ; 59(12): 2367-2378, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37650814

RESUMEN

Irregular words cannot be read correctly by decoding letters into sounds using the most common letter-sound mapping relations. They are difficult to read and learn. Cognitive models of word reading and development as well as empirical data suggest that inhibitory control might be important for irregular word reading and its development. The current study tested this in a U.K. population-based cohort (N = 529, 52.74% male, 90.17% White) in which children were assessed longitudinally at ages 5-6, 7-8, and 10-11 years. Results showed that inhibitory control did not predict concurrent irregular word reading after controlling for the covariates of decoding and vocabulary. However, inhibitory control made a small but significant contribution to growth in irregular word reading across time points, over and above vocabulary (decoding did not predict growth). Therefore, children might need to inhibit the predisposition to overgeneralize the most common relations between letters and sounds when learning to read irregular words. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Lectura , Vocabulario , Niño , Humanos , Masculino , Femenino , Estudios Longitudinales , Aprendizaje
5.
Q J Exp Psychol (Hove) ; 76(7): 1658-1671, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36282017

RESUMEN

From mid-childhood onwards, most new words are learned through reading. The precise meaning of many words depends upon the linguistic context in which they are encountered, which readers use to infer the appropriate interpretation. However, it is unclear what features of these linguistic contexts best support learning of new word meanings. We investigated whether learning words in contextually diverse sentences benefits word form and meaning learning in adults (n = 239). Participants learned meanings for 8 pseudowords through reading 10 sentences about each. Four pseudowords were learned in a diverse condition (10 sentences on different topics) and four were learned in a non-diverse condition (10 sentences on the same topic). An old-new decision post-test indicated that diversity did not influence word form learning. In a second post-test, participants chose which trained pseudoword completed a sentence from either an unfamiliar, untrained context, or a familiar, trained context. For familiar contexts, accuracy was higher for pseudowords learned in the non-diverse condition, but for unfamiliar contexts, accuracy was higher for pseudowords learned in the diverse condition. These results suggest that diverse contexts may promote development of flexible, decontextualised meaning representations that are easier to generalise to new contexts. Conversely, non-diverse contexts may favour extraction of context-bound representations that are more easily used in the same context.


Asunto(s)
Lectura , Semántica , Adulto , Humanos , Niño , Aprendizaje , Aprendizaje Verbal , Lenguaje
6.
R Soc Open Sci ; 9(12): 210555, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36533201

RESUMEN

High-quality lexical representations depend on robust representations of written form (orthography), spoken form (phonology) and meaning (semantics), and strong bonds between them. Quality of lexical representations may be affected by amount of print exposure and the form of individual words. Words that are harder to decode (print-to-sound) may lead to fuzzy representations of the orthographic and phonological forms, potentially creating less stable foundations for semantic knowledge. These factors are difficult to disentangle in natural language research; in this registered report, we experimentally manipulated decoding ease and exposure at the item level. Adults read paragraphs describing invented meanings of pseudowords. Pseudowords appeared two or six times in a paragraph, and had easy (e.g. bamper) or hard (e.g. uzide) to decode spelling-sound mappings. Post-tests assessed word-form knowledge, orthography-semantic mappings and semantic-phonology mappings. Results showed that greater decoding ease improved learning of word forms and consequently also impacted on word meanings. Higher exposure frequency improved learning of word forms but not meanings. Exposure frequency also modulated the effect of decoding ease on word-form learning, with a stronger effect of decoding ease for fewer exposures. Disentangling effects of decoding ease from print exposure has important implications for understanding potential barriers to vocabulary learning.

7.
Psychol Sci ; 32(4): 471-484, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33634711

RESUMEN

There is profound and long-standing debate over the role of explicit instruction in reading acquisition. In this research, we investigated the impact of teaching regularities in the writing system explicitly rather than relying on learners to discover these regularities through text experience alone. Over 10 days, 48 adults learned to read novel words printed in two artificial writing systems. One group learned spelling-to-sound and spelling-to-meaning regularities solely through experience with the novel words, whereas the other group received a brief session of explicit instruction on these regularities before training commenced. Results showed that virtually all participants who received instruction performed at ceiling on tests that probed generalization of underlying regularities. In contrast, despite up to 18 hr of training on the novel words, less than 25% of discovery learners performed on par with those who received instruction. These findings illustrate the dramatic impact of teaching method on outcomes during reading acquisition.


Asunto(s)
Aprendizaje , Lectura , Adulto , Generalización Psicológica , Humanos , Lenguaje , Escritura
8.
Br J Dermatol ; 185(1): 185-194, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33454963

RESUMEN

BACKGROUND: Little is known about the aetiologies and relevant allergens in paediatric patients with hand eczema (HE). OBJECTIVES: To characterize the aetiologies and determine the proportion of positive and currently relevant allergens in children/adolescents (age < 18 years) with HE referred for patch testing. METHODS: A retrospective analysis (2000-2016) of North American Contact Dermatitis Group data was performed. RESULTS: Of 1634 paediatric patients, 237 (14·5%) had involvement of the hands. Final physician diagnoses included allergic contact dermatitis (49·4%), atopic dermatitis (37·1%) and irritant contact dermatitis (16·9%). In multivariable logistic regression models, employment was the only association with increased odds of any HE or primary HE. Children with HE vs. those without HE had similar proportions of positive patch tests (56·1% vs. 61·7%; χ2 -test, P = 0·11). The five most common currently relevant allergens were nickel, methylisothiazolinone, propylene glycol, decyl glucoside and lanolin. In multivariable logistic regression models of the top 20 relevant allergens, HE was associated with significantly higher odds of currently relevant reactions to lanolin, quaternium-15, Compositae mix, thiuram mix, 2-mercaptobenzathiazole and colophony. The allergens with the highest mean significance-prevalence index number were methylisothiazolinone, carba mix, thiuram mix, nickel and methylchloroisothiazolinone/methylisothiazolinone. CONCLUSIONS: Children with HE who were referred for patch testing had a high proportion of positive patch tests, which was similar to the proportion found in children without HE. Children with HE had a distinct and fairly narrow profile of currently relevant allergens.


Asunto(s)
Dermatitis Alérgica por Contacto , Eccema , Adolescente , Alérgenos/efectos adversos , Niño , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/epidemiología , Dermatitis Alérgica por Contacto/etiología , Eccema/inducido químicamente , Eccema/diagnóstico , Eccema/epidemiología , Humanos , América del Norte/epidemiología , Pruebas del Parche , Estudios Retrospectivos
9.
Cogn Psychol ; 123: 101336, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32823169

RESUMEN

Reading acquisition involves learning to associate visual symbols with spoken language. Multiple lines of evidence indicate that instruction on the relationship between spellings and sounds may be particularly important.However, it is unclear whether the effectiveness of this form of instruction depends on pre-existing oral language knowledge.To investigate this issue, we developed a series of computational models of reading incorporating orthographic, phonological and semantic processing to simulate bothartificialand natural orthographic learning conditions in adults and children. We exposed the models to instruction focused on spelling-sound or spelling-meaning relationships, and tested the influence of the models' oral language proficiency on the effectiveness of these training regimes. Overall, the simulations indicated thatoral language proficiency is a vital foundation for reading acquisition, and may modulate the effectiveness of reading instruction. These results provide a computational basis for the Simple View of Reading,and emphasise the importance of both oral language knowledge and spelling-sound instructionin the initial stages of learning to read.


Asunto(s)
Lenguaje , Lectura , Adulto , Niño , Simulación por Computador , Humanos , Modelos Teóricos , Fonética , Semántica , Vocabulario
10.
Proc Natl Acad Sci U S A ; 116(36): 17723-17728, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31427523

RESUMEN

Reading involves transforming arbitrary visual symbols into sounds and meanings. This study interrogated the neural representations in ventral occipitotemporal cortex (vOT) that support this transformation process. Twenty-four adults learned to read 2 sets of 24 novel words that shared phonemes and semantic categories but were written in different artificial orthographies. Following 2 wk of training, participants read the trained words while neural activity was measured with functional MRI. Representational similarity analysis on item pairs from the same orthography revealed that right vOT and posterior regions of left vOT were sensitive to basic visual similarity. Left vOT encoded letter identity and representations became more invariant to position along a posterior-to-anterior hierarchy. Item pairs that shared sounds or meanings, but were written in different orthographies with no letters in common, evoked similar neural patterns in anterior left vOT. These results reveal a hierarchical, posterior-to-anterior gradient in vOT, in which representations of letters become increasingly invariant to position and are transformed to convey spoken language information.


Asunto(s)
Lenguaje , Imagen por Resonancia Magnética , Lóbulo Occipital , Lectura , Aprendizaje Verbal/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Occipital/fisiología
11.
Cortex ; 116: 268-285, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30037636

RESUMEN

Morphological processing, the ability to extract information about word structure, is an essential component of reading. Functional MRI studies have identified several cortical regions involved in morphological processing, but the white matter pathways that support this skill remain unknown. Here, we examine the relationship between behavioral measures of morphological processing and microstructural properties of white matter pathways. Using diffusion MRI (dMRI), we identified the major ventral and dorsal reading pathways in a group of 45 adult English readers. The same participants completed a behavioral battery that included a morphological task and measures of phonological and orthographic processing. We found significant correlations between morphological processing skill and microstructural properties of the ventral, but not dorsal, pathways. These correlations were detected primarily in the left hemisphere, and remained significant after controlling for phonological or orthographic measures, suggesting some level of cognitive specificity. Morphological processing of written words thus appears to rely on ventral pathways, primarily in the left hemisphere. This finding supports the contribution of morphological processing to lexical access and comprehension of complex English words.


Asunto(s)
Encéfalo/anatomía & histología , Encéfalo/fisiología , Lectura , Sustancia Blanca/anatomía & histología , Adulto , Mapeo Encefálico/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Estimulación Luminosa , Sustancia Blanca/fisiología , Escritura
12.
Q J Exp Psychol (Hove) ; 71(7): 1501-1505, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29741458

RESUMEN

We previously reported an artificial language learning study designed to compare methods of reading instruction that emphasise learning the relationship between spelling and sound versus learning the relationship between spelling and meaning. Behavioural and neural data supported emphasis on spelling-sound knowledge, and we therefore advocated use of phonics in the initial stages of learning to read. Bowers and Bowers argue that these conclusions are not justified because we (a) mischaracterised the English writing system and (b) mischaracterised the meaning-based instruction used in schools. In this article, we respond to the first point by showing that the novel words used previously were a good approximation to the types of written words that children are exposed to in the first year of reading instruction. We respond to the second point by showing that while enhancements to meaning-based instruction can assist pupils to infer the meanings of unfamiliar words, these methods actually disadvantage long-term learning of those words. We conclude by suggesting that reading instruction should be based on an understanding of the writing system, properly characterised across the trajectory of learning. This means emphasis on spelling-sound regularities in the initial stage of learning to read and increasing emphasis on spelling-meaning regularities as children gain greater experience with text.


Asunto(s)
Lenguaje , Lectura , Niño , Comprensión , Humanos , Aprendizaje , Escritura
13.
J Exp Psychol Gen ; 146(6): 826-858, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28425742

RESUMEN

There is strong scientific consensus that emphasizing print-to-sound relationships is critical when learning to read alphabetic languages. Nevertheless, reading instruction varies across English-speaking countries, from intensive phonic training to multicuing environments that teach sound- and meaning-based strategies. We sought to understand the behavioral and neural consequences of these differences in relative emphasis. We taught 24 English-speaking adults to read 2 sets of 24 novel words (e.g., /buv/, /sig/), written in 2 different unfamiliar orthographies. Following pretraining on oral vocabulary, participants learned to read the novel words over 8 days. Training in 1 language was biased toward print-to-sound mappings while training in the other language was biased toward print-to-meaning mappings. Results showed striking benefits of print-sound training on reading aloud, generalization, and comprehension of single words. Univariate analyses of fMRI data collected at the end of training showed that print-meaning relative to print-sound relative training increased neural effort in dorsal pathway regions involved in reading aloud. Conversely, activity in ventral pathway brain regions involved in reading comprehension was no different following print-meaning versus print-sound training. Multivariate analyses validated our artificial language approach, showing high similarity between the spatial distribution of fMRI activity during artificial and English word reading. Our results suggest that early literacy education should focus on the systematicities present in print-to-sound relationships in alphabetic languages, rather than teaching meaning-based strategies, in order to enhance both reading aloud and comprehension of written words. (PsycINFO Database Record


Asunto(s)
Encéfalo/diagnóstico por imagen , Comprensión/fisiología , Lenguaje , Lectura , Adolescente , Adulto , Encéfalo/fisiología , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Vocabulario , Adulto Joven
14.
Neuropsychologia ; 98: 68-84, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27720949

RESUMEN

Understanding the neural processes that underlie learning to read can provide a scientific foundation for literacy education but studying these processes in real-world contexts remains challenging. We present behavioural data from adult participants learning to read artificial words and name artificial objects over two days. Learning profiles and generalisation confirmed that componential learning of visual-verbal associations distinguishes reading from object naming. Functional MRI data collected on the second day allowed us to identify the neural systems that support componential reading as distinct from systems supporting holistic visual-verbal associations in object naming. Results showed increased activation in posterior ventral occipitotemporal (vOT), parietal, and frontal cortices when reading an artificial orthography compared to naming artificial objects, and the reverse profile in anterior vOT regions. However, activation differences between trained and untrained words were absent, suggesting a lack of cortical representations for whole words. Despite this, hippocampal responses provided some evidence for overnight consolidation of both words and objects learned on day 1. The comparison between neural activity for artificial words and objects showed extensive overlap with systems differentially engaged for real object naming and English word/pseudoword reading in the same participants. These findings therefore provide evidence that artificial learning paradigms offer an alternative method for studying the neural systems supporting language and literacy. Implications for literacy acquisition are discussed.


Asunto(s)
Asociación , Mapeo Encefálico , Encéfalo/fisiología , Recuerdo Mental/fisiología , Lectura , Aprendizaje Verbal/fisiología , Estimulación Acústica , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Nombres , Oxígeno/sangre , Reconocimiento Visual de Modelos , Fonética , Estimulación Luminosa , Tiempo de Reacción , Vocabulario , Adulto Joven
15.
Neuroimage ; 128: 328-341, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26806289

RESUMEN

In this study predictions of the dual-route cascaded (DRC) model of word reading were tested using fMRI. Specifically, patterns of co-localization were investigated: (a) between pseudoword length effects and a pseudowords vs. fixation contrast, to reveal the sublexical grapho-phonemic conversion (GPC) system; and (b) between word frequency effects and a words vs. pseudowords contrast, to reveal the orthographic and phonological lexicon. Forty four native speakers of Greek were scanned at 3T in an event-related lexical decision task with three event types: (a) 150 words in which frequency, length, bigram and syllable frequency, neighborhood, and orthographic consistency were decorrelated; (b) 150 matched pseudowords; and (c) fixation. Whole-brain analysis failed to reveal the predicted co-localizations. Further analysis with participant-specific regions of interest defined within masks from the group contrasts revealed length effects in left inferior parietal cortex and frequency effects in the left middle temporal gyrus. These findings could be interpreted as partially consistent with the existence of the GPC system and phonological lexicon of the model, respectively. However, there was no evidence in support of an orthographic lexicon, weakening overall support for the model. The results are discussed with respect to the prospect of using neuroimaging in cognitive model evaluation.


Asunto(s)
Encéfalo/fisiología , Reconocimiento Visual de Modelos/fisiología , Lectura , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Reconocimiento en Psicología/fisiología , Adulto Joven
16.
Neuroimage ; 99: 419-33, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24904992

RESUMEN

It has been suggested that differential neural activity in imaging studies is most informative if it is independent of response time (RT) differences. However, others view RT as a behavioural index of key cognitive processes, which is likely linked to underlying neural activity. Here, we reconcile these views using the effort and engagement framework developed by Taylor, Rastle, and Davis (2013) and data from the domain of reading aloud. We propose that differences in neural engagement should be independent of RT, whereas, differences in neural effort should co-vary with RT. We illustrate these different mechanisms using data from an fMRI study of neural activity during reading aloud of regular words, irregular words, and pseudowords. In line with our proposals, activation revealed by contrasts designed to tap differences in neural engagement (e.g., words are meaningful and therefore engage semantic representations more than pseudowords) survived correction for RT, whereas activation for contrasts designed to tap differences in neural effort (e.g., it is more difficult to generate the pronunciation of pseudowords than words) correlated with RT. However, even for contrasts designed to tap neural effort, activity remained after factoring out the RT-BOLD response correlation. This may reveal unpredicted differences in neural engagement (e.g., learning phonological forms for pseudowords>words) that could further the development of cognitive models of reading aloud. Our framework provides a theoretically well-grounded and easily implemented method for analysing and interpreting RT effects in neuroimaging studies of cognitive processes.


Asunto(s)
Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Tiempo de Reacción/fisiología , Adolescente , Adulto , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Aprendizaje/fisiología , Masculino , Corteza Prefrontal/fisiología , Lectura , Adulto Joven
17.
Vaccine ; 32(29): 3675-9, 2014 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-24814554

RESUMEN

Skunks are one of the most important rabies vector species in North America due to their wide geographic distribution, high susceptibility to the rabies virus, and tendency to inhabit areas around human dwellings and domestic animals. Oral vaccination is a cost-effective, socially acceptable technique often used to control rabies in terrestrial wildlife; however, control of rabies in skunks has proven especially challenging due to the lack of a vaccine effective by the oral route in this species. In this study, we examined the antibody response of captive striped skunks (Mephitis mephitis) to ONRAB(®) and tested the protection afforded by the vaccine against rabies virus. Thirty-one skunks were each offered one ONRAB(®) vaccine bait, 25 skunks were administered ONRAB(®) via direct instillation into the oral cavity (DIOC) and ten controls received no vaccine. A blood sample was collected from controls and vaccinates 6 weeks prior to treatment, and then 5 and 7 weeks post-vaccination (PV). A competitive ELISA was used to detect rabies antibody (RAb). Pre-vaccination sera for all skunks, and sera for all controls throughout the serology study, were negative for RAb. Fifty-eight percent (18/31) of skunks in the bait group and 100% (25/25) of skunks that received ONRAB(®) DIOC had detectable RAb by 7 week PV. All 10 controls succumbed to experimental rabies infection. In the group of skunks administered ONRAB(®) DIOC, 100% (23/23) survived challenge 247 days PV. Survival of skunks presented ONRAB(®) baits was 81% (25/31). In the bait group, all 18 skunks that had detectable RAb by 7 week PV survived challenge. Seven additional skunks without detectable RAb prior to week 7 PV also survived. Lack of any remarkable pathology in study animals, together with positive serology and challenge results, supports that ONRAB(®) is a safe and effective oral rabies vaccine for use in skunks.


Asunto(s)
Mephitidae/inmunología , Vacunas Antirrábicas/inmunología , Rabia/prevención & control , Administración Oral , Animales , Animales Salvajes/inmunología , Animales Salvajes/virología , Anticuerpos Antivirales/sangre , Reservorios de Enfermedades , Femenino , Inmunidad Humoral , Masculino , Mephitidae/virología , Distribución Aleatoria , Vacunación/métodos
18.
J Cogn Neurosci ; 26(9): 2128-54, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24666161

RESUMEN

Understanding the neural systems that underpin reading acquisition is key if neuroscientific findings are to inform educational practice. We provide a unique window into these systems by teaching 19 adults to read 24 novel words written in unfamiliar letters and to name 24 novel objects while in an MRI scanner. Behavioral performance on trained items was equivalent for the two stimulus types. However, componential letter-sound associations were extracted when learning to read, as shown by correct reading of untrained words, whereas object-name associations were holistic and arbitrary. Activity in bilateral anterior fusiform gyri was greater during object name learning than learning to read, and ROI analyses indicated that left mid-fusiform activity was predictive of success in object name learning but not in learning to read. In contrast, activity in bilateral parietal cortices was predictive of success for both stimulus types but was greater during learning and recall of written word pronunciations relative to object names. We argue that mid-to-anterior fusiform gyri preferentially process whole items and contribute to learning their spoken form associations, processes that are required for skilled reading. In contrast, parietal cortices preferentially process componential visual-verbal mappings, a process that is crucial for early reading development.


Asunto(s)
Mapeo Encefálico , Corteza Cerebral/fisiología , Nombres , Lectura , Aprendizaje Verbal/fisiología , Vocabulario , Adolescente , Adulto , Aprendizaje por Asociación/fisiología , Peróxido de Carbamida , Corteza Cerebral/irrigación sanguínea , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Recuerdo Mental/fisiología , Peróxidos/sangre , Tiempo de Reacción/fisiología , Factores de Tiempo , Urea/análogos & derivados , Urea/sangre , Adulto Joven
19.
Eur J Gynaecol Oncol ; 35(6): 641-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25556268

RESUMEN

OBJECTIVE: To describe the clinical outcomes of histologically confirmed adenocarcinoma in situ (AIS) of the cervix treated with cervical conization. MATERIALS AND METHODS: A retrospective chart review of patients with histologically confirmed AIS from July 1998 to February 2011 included 52 patients. The rates of residual disease in subsequent excisions, the clinical recurrence rate, the average disease-free interval, and risk of progression to adenocarcinoma were described. The clinical outcomes of patients treated with cold knife cone (CKC) and loop electrosurgical excisional procedure (LEEP) were compared. RESULTS: Fifteen LEEPs and 37 CKC procedures were performed as initial treatment and 26 patients (50%) had positive margins. There was no significant difference in rate of positive margins between LEEP and CKC (40% vs. 54%, respectively. p = 0.55). LEEPs and CKCs resulted in similar volumes of cervical tissue resected (4.98 cm3 vs. 5.04 cm3, p = 0.40). Of patients with positive margins, ten underwent immediate hysterectomy, six underwent a second cone biopsy, seven were managed expectantly, and four were lost to follow up. Residual AIS was found in 47% (eight of 17) of repeat cone biopsy and hysterectomy specimens performed for positive cone margins. Of the 26 patients with negative cone margins, no residual or recurrent disease was found after an average follow-up of 32 months. CONCLUSIONS: A positive surgical margin was associated with residual disease in 47% of patients with AIS treated with conization. No patient with negative cone margins had recurrent or progressive disease. Cervical conization with negative margins appears to be a safe treatment option for patients with AIS but requires further investigation. CKC and LEEP were equally efficacious treatments in our study population.


Asunto(s)
Adenocarcinoma in Situ/cirugía , Conización , Neoplasias del Cuello Uterino/cirugía , Adolescente , Adulto , Electrocirugia , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
20.
Vaccine ; 32(8): 984-9, 2014 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-24374501

RESUMEN

Twenty-seven red foxes (Vulpes vulpes) were each offered a bait containing ONRAB, a recombinant oral rabies vaccine that uses a human adenovirus vector to express the immunogenic rabies virus glycoprotein; 10 controls received no vaccine baits. Serum samples collected from all foxes before treatment, and each week post-treatment for 16 weeks, were tested for the presence of rabies virus neutralizing antibody (RVNA). In the bait group, a fox was considered a responder to vaccination if serum samples from 3 or more consecutive weeks had RVNA ≥0.5 IU/ml. Using this criterion, 79% of adult foxes (11/14) and 46% of juveniles (6/13) responded to vaccination with ONRAB. Serum RVNA of adults first tested positive (≥0.5 IU/ml) between weeks 1 and 3, about 4 weeks earlier than in juveniles. Adults also responded with higher levels of RVNA and these levels were maintained longer. Serum samples from juveniles tested positive for 1-4 consecutive weeks; in adults the range was 2-15 weeks, with almost half of adults maintaining titres above 0.5 IU/ml for 9 or more consecutive weeks. Based on the kinetics of the antibody response to ONRAB, the best time to sample sera of wild adult foxes for evidence of vaccination is 7-11 weeks following bait distribution. Thirty-four foxes (25 ONRAB, 9 controls) were challenged with vulpine street virus 547 days post-vaccination. All controls developed rabies whereas eight of 13 adult vaccinates (62%) and four of 12 juvenile vaccinates (33%) survived. All foxes classed as non-responders to vaccination developed rabies. Of foxes considered responders to vaccination, 80% of adults (8/10) and 67% of juveniles (4/6) survived challenge. The duration of immunity conferred to foxes would appear adequate for bi-annual and annual bait distribution schedules as vaccinates were challenged 1.5 years post-vaccination.


Asunto(s)
Zorros/inmunología , Vacunas Antirrábicas/administración & dosificación , Rabia/prevención & control , Adenoviridae , Administración Oral , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Inmunidad Humoral , Vacunas Sintéticas/administración & dosificación
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