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D Howard

Publications and source records attributed to D Howard.

At least 37 records · Page 2Linked to original sources
PubMed2001

Noun-verb differences? a question of semantics: a response to shapiro and caramazza.

We presented a new model using the sensory/functional theory of semantic category deficits to explain noun/verb deficits in aphasia. The predictions arising from this model were tested on a small number of patients exhibiting grammatical and/or semantic category specific deficits in picture naming. The results lent support for the theory presented. Shapiro and Caramazza (this issue) raised several objections to this theory (which they call the "extended sensory functional theory," or ESFT). In this article we address their concerns about the validity of the ESFT and conclude that it is indeed a useful model that provides a parsimonious explanation for many diverse patterns of deficits.

Aphasia↗
PubMed2001

An investigation of the interaction between thematic and phrasal structure in nonfluent agrammatic subjects.

Garrett (1982) developed a model of normal sentence production which has been used in the description of aphasic language (Schwartz, 1987). This study investigated the effects of the thematic representation specified at the functional level on the complexity of the phrases produced at the positional level. A group of 14 nonfluent, agrammatic subjects were compared to 20 normal controls in their production of the story of Cinderella. The agrammatic subjects produced fewer argument structures than the normal control subjects. Their phrasal realization of the arguments, however, was not qualitatively different from that of the normal subjects. In both cases, with an increase in the number of arguments, there was a concurrent increase in the mean complexity of the phrases used to realize those arguments and in the total phrasal complexity of the utterances. The complexity of noun phrases differed according to the thematic roles expressed; this seemed to be a consequence of their different locations in the sentence. Preverbal noun phrases were much less complex than postverbal noun phrases. There was no evidence to suggest that there was a trade-off between the production of thematic structure and subsequent phrasal production. Neither was there evidence to suggest that production differed according to whether the phrase was an argument of the verb or a nonargument. The complexity of a phrase was determined by the type of information it conveyed.

Adolescent↗
PubMed2001

The functional anatomy of the female pelvic floor and stress continence control system.

This paper provides an overview of the functional anatomy of the structures responsible for controlling urinary continence under stress. The stress continence control system can be divided into two parts: the system responsible for bladder neck support, and the system responsible for sphincteric closure. Age- and injury-related changes in each of these systems are discussed. Understanding the pathophysiology of incontinence on the anatomical level will help to lead to identification of specific defects, thereby allowing better individualized treatment for the incontinent patient.

Female↗
PubMed2001

CT guided percutaneous fixation of sacroiliac fractures in trauma patients.

BACKGROUND: Open reduction and internal fixation of unstable pelvic fractures has been advocated to minimize complications and avoid further injury. We have recently performed CT guided percutaneous fixation of sacroiliac joints as an alternative to open repair. METHODS: From May 1, 1998 to April 30, 1999, our Level II trauma center admitted 76 patients with pelvic fractures, all due to blunt trauma. Twenty patients with unstable sacroiliac fracture-distractions underwent 22 percutaneous fixation procedures under general anesthesia in the radiology department by the third hospital day. Procedure times averaged 82 minutes. Localization with CT guidance was performed by the radiologist using 3-D images followed by percutaneous screw placement by the orthopaedic surgeon. RESULTS: There was minimal procedural blood loss and no post-procedural wound complications. There was one operative delay due to respiratory difficulties and one postoperative death unrelated to the pelvic fracture. All patients were mobilized on the first post-procedural day. CONCLUSION: CT guided fixation of unstable pelvic fractures minimizes blood loss during a short procedure with few subsequent complications and allows early mobilization of the patients.

Accidents, Traffic↗
PubMed2001

Semantic memory is impaired in both dementia with Lewy bodies and dementia of Alzheimer's type: a comparative neuropsychological study and literature review.

OBJECTIVE: To test the hypothesis that semantic impairment is present in both patients with dementia with Lewy bodies (DLB) and those with dementia of Alzheimer's type (DAT). METHODS: A comprehensive battery of neuropsychological tasks designed to assess semantic memory, visuoperceptual function, verbal fluency, and recognition memory was given to groups of patients with DLB (n=10), DAT (n=10) matched pairwise for age and mini mental state examination (MMSE), and age matched normal controls (n=15). RESULTS: Both DLB and DAT groups exhibited impaired performance across the range of tasks designed to assess semantic memory. Whereas patients with DAT showed equivalent comprehension of written words and picture stimuli, patients with DLB demonstrated more severe semantic deficits for pictures than words. As in previous studies, patients with DLB but not those with DAT were found to have impaired visuoperceptual functioning. Letter and category fluency were equally reduced for the patients with DLB whereas performance on letter fluency was significantly better in the DAT group. Recognition memory for faces and words was impaired in both groups. CONCLUSIONS: Semantic impairment is not limited to patients with DAT. Patients with DLB exhibit particular problems when required to access meaning from pictures that is most likely to arise from a combination of semantic and visuoperceptual impairments.

Aged↗
PubMed2001

Exposure to febrile temperature modifies endothelial cell response to tumor necrosis factor-alpha.

Fever is an important regulator of inflammation that modifies expression and bioactivity of cytokines, including tumor necrosis factor (TNF)-alpha. Pulmonary vascular endothelium is an important target of TNF-alpha during the systemic inflammatory response. In this study, we analyzed the effect of a febrile range temperature (39.5 degrees C) on TNF-alpha-stimulated changes in endothelial barrier function, capacity for neutrophil binding and transendothelial migration (TEM), and cytokine secretion in human pulmonary artery endothelial cells (EC). Permeability for [(14)C]BSA tracer was increased by treatment with TNF-alpha, and this effect was augmented by incubating EC at 39.5 degrees C. Treating EC with 2. 5 U/ml TNF-alpha stimulated an increase in subsequent neutrophil adherence and TEM. Incubating EC at 39.5 degrees C caused a 30% increase in TEM but did not modify the enhancement of neutrophil adherence or TEM by TNF-alpha treatment. Analysis of cytokine expression in EC cultures exposed to TNF-alpha at either 37 degrees or 39.5 degrees C revealed three patterns of temperature and TNF-alpha responsiveness. Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin (IL)-8 were not detectable in untreated EC but were increased after TNF-alpha exposure, and this increase was enhanced at 39.5 degrees C. IL-6 expression was also increased with TNF-alpha exposure, but IL-6 expression was lower in 39.5 degrees C EC cultures. Transforming growth factor-beta(1) was constitutively expressed, and its expression was not influenced either by TNF-alpha or exposure to 39.5 degrees C. These data demonstrate that clinically relevant shifts in body temperature might cause important changes in the effects of proinflammatory cytokines on the endothelium.

Body Temperature↗
PubMed2001

MIRABEL: models for integrated review and assessment of biodiversity in European landscapes.

In this paper, we present the methodology and some results from the application of an integrating conceptual framework, MIRABEL, to analyze the consequences of environmental change for biodiversity. For 28 European countries, MIRABEL tabulates changes in the status of threatened habitats predicted to result from 10 environmental pressures. Regional variations in the severity of the pressures and impacts are taken into account by compiling separate impact tables for each of 13 Ecological Regions. Results suggest that agricultural intensification is one of the main threats, however, differences recorded by MIRABEL in the intensity of the pressures, their rate of change and their past and expected impacts on biodiversity in the various Ecological Regions is telling evidence of Europe's biogeographical variety, and of the need to take this into consideration when assessing environmental change.

Ecosystem↗
PubMed2001

Phonological and orthographic approaches to the treatment of word retrieval in aphasia.

We present a preliminary report on a study of the treatment of word finding difficulties in aphasia using phonological and orthographic cues. These techniques although often used to cue word finding in the immediate term have been little evaluated in terms of therapy designed to improve word retrieval in the long term. The first phase using cued word retrieval in a picture naming task was followed by a second phase designed to facilitate use of treated words in real-life contexts. The results from both phases were encouraging with improved word retrieval for three out of the four participants. The implications for clinical practice are discussed.

Aphasia↗
PubMed2001

Treatment of word retrieval in aphasia: generalisation to conversational speech.

The question of whether treatment gains in picture naming generalise to conversation remains relatively unexplored. Several difficulties surround data collection and analysis. A quantitative measure of word retrieval in aphasia is presented along with relevant details relating to the reliability of the measure, and the relationship between word retrieval in picture naming and noun retrieval in conversation. We discuss the clinical application of the measure and its applicability outside the field of aphasia.

Aphasia↗
PubMed2001

Age of acquisition and imageability ratings for a large set of words, including verbs and function words.

Age of acquisition and imageability ratings were collected for 2,645 words, including 892 verbs and 213 function words. Words that were ambiguous as to grammatical category were disambiguated: Verbs were shown in their infinitival form, and nouns (where appropriate) were preceded by the indefinite article (such as to crack and a crack). Subjects were speakers of British English selected from a wide age range, so that differences in the responses across age groups could be compared. Within the subset of early acquired noun/verb homonyms, the verb forms were rated as later acquired than the nouns, and the verb homonyms of high-imageability nouns were rated as significantly less imageable than their noun counterparts. A small number of words received significantly earlier or later age of acquisition ratings when the 20-40 years and 50-80 years age groups were compared. These tend to comprise words that have come to be used more frequently in recent years (either through technological advances or social change), or those that have fallen out of common usage. Regression analyses showed that although word length, familiarity, and concreteness make independent contributions to the age of acquisition measure, frequency and imageability are the most important predictors of rated age of acquisition.

Aged↗
PubMed2001

The effects of age on accident severity and outcome in Irish road traffic accident patients.

Road traffic accidents (RTA's) are the leading cause of fatal trauma in Ireland. Although older drivers are the safest group of drivers in the population, once involved in a crash they are more likely to sustain a severe injury or death. The experiences of Irish elderly RTA victims has not been previously documented. We studied older RTA patients admitted to two Irish trauma centres in 1995. Of 525 patients, 39 (7%) were aged over 65. We compared 38 patients aged 16-64 years for comparison and reviewed the notes in detail. Elderly patients were mostly pedestrians (23/38 - 61%) though 21% (8/38) were drivers with 8% (3/38) on public transport. Younger patients were mostly drivers (14/37 - 38%), cyclists (9/37 - 24%) or motorcyclists (7/37 - 19%). Older patients had a higher median Injury Severity Score, p < 0.05, were more likely to be female (p<0.01), involved in RTA's between 9am-5pm (p<0.05) and have pre-existing medical conditions (p<0.01). The following were significantly increased in older patients (p values): surgical (<0.01), medical (<0.01) and therapist workload (p<0.05), complications (<0.0001), length of stay (<0.01). Less elderly were discharged directly to home (p<0.001). Strategies to reduce the mortality and morbidity associated with RTA in the elderly should emphasise a) older pedestrians during daytime hours, b) attention to safety in public transport. Treatment must ensure adequate medical and therapist input to anticipate higher complication rates.

Accidents, Traffic↗
PubMed2000

Prey, parasites and pathology associated with the mortality of a juvenile gray whale (Eschrichtius robustus) stranded along the northern California coast.

An eastern Pacific gray whale (Eschrichtius robustus) stranded off Pelican Point, Tomales Bay, California, USA, was examined for physiological parameters, prey, parasites and associated pathology. The whale was emaciated, and hematological examination revealed an elevation in hematocrit, serum sodium, potassium, electrolyte values and hypoglycemia. Parasites recovered included 5 species, 1 ectoparasite (Cyamus scammoni), and 4 helminths (Anisakis simplex, Ogmogaster antarcticus, Ogmogaster pentalineatus, Bolbosoma balanae) with the latter causing multifocal transmural abscesses. Histological examination indicated severe acute lung congestion, minimal, multifocal, lymphocytic, interstitial myocarditis, and mild hepatocellular and Kupffer cell hemosiderosis. The prey taxa present in the stomach indicated the whale was feeding on hard bottom communities prior to death.

Animals↗
PubMed2000

Why is a verb like an inanimate object? Grammatical category and semantic category deficits.

Semantic category effects, such as difficulties in naming animate things relative to inanimate objects, have been explained in terms of the relative weightings of perceptual and functional features within the semantic representations of these concepts. We argue that grammatical category deficits, such as difficulties in naming nouns relative to verbs, can be explained within the same framework. We hypothesize that verb concepts are richer in functional than sensory features and present a model of the semantic representations of animate nouns, inanimate nouns, and verbs. The model demonstrates that sensory feature damage results in a deficit for naming living things but spares verb naming, and functional feature damage results in a deficit for naming inanimate objects and verbs. We then report the assessment results of two patient groups. In accordance with the model's predictions, the "verb spared" patients were consistently worse at naming living things than inanimate objects, and their definitions of both living and nonliving items were lacking in sensory information. We conclude that damage to sensory features in semantic representations causes difficulties in naming concrete nouns relative to action verbs, and within the grammatical category of nouns, animate items will be more severely affected. Imageability was shown to be a strong predictor of naming performance in the "verb deficit" patients, and when this variable was controlled no class effect remained. Production of definitions revealed no differential damage to sensory or functional features, and no consistent effect of animacy in naming was shown. While the model suggests that verb deficits might occur in patients for whom functional features are damaged relative to sensory features, we conclude that the "verb deficit" shown in our patients (and potentially in many previously reported cases) was an artifact of the lower imageability of verbs in confrontation naming tasks.

Aged↗
PubMed2000

Noun imageability and the temporal lobes.

We used positron emission tomography to investigate brain activity in response to hearing or reading nouns of varying imageability. Three experiments were performed. Activity increased with noun imageability in the left mid-fusiform gyrus, the lateral parahippocampal area in humans, and in the rostral medial temporal lobes close to or within perirhinal cortex. The left mid-fusiform activation has been observed in previous imaging studies of single word processing. Its functional significance was variously attributed to semantic processing, visual imagery, encoding episodic memories, or the integration of lexical inputs from different sensory modalities. These hypotheses are not mutually exclusive. The more rostral medial lobe response to noun imageability has not been observed previously. However, lesions in perirhinal cortex impair knowledge about objects in non-human primates, and bilateral rostral ventromedial temporal lobe potentials in response to object nouns were observed with human intracranial recordings. Imageable (object) nouns are learnt with reference to sensory experiences of living and non-living objects, whereas acquisition of the meaning of low imageable (abstract) nouns is more dependent on their context within sentences. Parahippocampal and perirhinal cortices are reciprocally connected with, respectively, second and third order sensory association cortices. We conclude that access to the representations of word meaning is dependent on heteromodal temporal lobe cortex, and that during the acquisition of object nouns one route is established through ventromedial temporal cortical regions that have reciprocal connections with all sensory association cortices.

Adult↗
PubMed2000

Racial differences in the structure and function of the stress urinary continence mechanism.

OBJECTIVE: To compare the structure and function of the urethral sphincter and the urethral support in nulliparous black and white women. METHODS: Eighteen black women (mean age 28.1 years) and 17 white women (mean age 31.3 years) completed this cross-sectional study. The following assessments were made: urethral function using multichannel cystometrics and urethral pressure profilometry, pelvic muscle strength using an instrumented speculum, urethral mobility using the cotton-swab test and perineal ultrasound, and pelvic muscle bulk using magnetic resonance imaging. RESULTS: Black women demonstrated a 29% higher average urethral closure pressure during a maximum pelvic muscle contraction (154 cm H(2)O versus 119 cm H(2)O in the white subjects; P =.008). Although not statistically significant, black women had a 14% higher maximum urethral closure pressure at rest (108 cm H(2)O versus 95 cm H(2)O; P =.23) and a 21% larger urethral volume (4818 mm(3) versus 3977 mm(3); P =.06). In addition, there was a 36% greater vesical neck mobility measured with the cotton-swab test (blacks 49 degrees versus whites 36 degrees; P =.02) and a 42% difference in ultrasonically measured vesical neck mobility during a maximum Valsalva effort (blacks = -17 mm versus whites -12 mm; P =.08). CONCLUSION: Functional and morphologic differences exist in the urethral sphincteric and support system of nulliparous black and white women.

Adult↗