Biomedical subjects

T J Edwards

Publications and source records attributed to T J Edwards.

9 recordsLinked to original sources

PubMed1995

Biological valves beyond fifteen years: the Wessex experience.

Between 1975 and 1979, 443 biological valves (298 Carpentier-Edwards, 134 homograft, and 11 Hancock valves) were implanted in 415 patients (age, 16 to 77 years; mean, 59 years) with an operative mortality of 2.9%. Total follow-up was 4,248 patient-years. Overall event-free survival was 60% +/- 1.5% (standard deviation) at 10 years and 29% +/- 1.4% at 15 years. Ten-year and 15-year event-free survival were 72% +/- 3.4% and 41% +/- 3.3% for aortic homografts, 62% +/- 3% and 33% +/- 2.8% for isolated aortic xenografts, and 43% +/- 3.5% and 14% +/- 3.0% for isolated mitral xenografts. Freedom from structural valve degeneration was 87% +/- 1.3% and 63% +/- 2.5% for all patients at 10 and 15 years, respectively, 86% +/- 2.7% and 58% +/- 4.1% for aortic homografts, 93% +/- 1.8% and 76% +/- 5.1% for aortic xenografts, and 75% +/- 4.0% and 47% +/- 7.4% for mitral xenografts. Of the 110 remaining patients, echocardiography was performed in 61 patients (23 aortic xenograft, 24 aortic homograft, 9 mitral xenograft, and 5 tricuspid xenograft) between 14 and 17 years after implantation. An early diastolic murmur was heard in 57% of all aortic valve replacements (AVRs) 62.5% of homograft AVRs, and 52% of xenograft AVRs. Echocardiographically, aortic regurgitation was detected in 79%, 83%, and 74% of all AVRs, homografts, and xenografts, respectively. Aortic stenosis was present clinically in 11% of all AVRs, 4% of homograft AVRs, and 17% of xenograft AVRs.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗

PubMed1992

Aggressive surgical management of sleep apnea syndrome in the syndromal craniosynostoses.

Obstructive sleep apnea syndrome (OSAS) frequently develops in patients with craniosynostosis and associated midfacial stenosis. In the past, conservative measures or tracheostomy have been used to manage this condition. Although the course of OSAS in these patients is multifactorial, a major factor is the marrow nasopharyngeal space. Aggressive surgical intervention to enlarge the nasopharyngeal space can reduce the severity of OSAS and therefore avoid the need for tracheostomy. Surgical approaches include adenotonsillectomy, uvulopalatopharyngoplasty, and midface advancement.

Child, Preschool↗

PubMed1991

Crouzon twins with cloverleaf skull malformations.

We describe unique monozygotic twins with Crouzon's disease and cloverleaf-shaped skull deformities who have been closely followed since birth. Their abnormal skull shapes were identified during antenatal ultrasound examination. The twins had gross exophthalmos and hydrocephalus with papilledema, so early calvarial decompression surgery was required. Although born to healthy parents of normal appearance, a third cousin of the twins had a milder form of Crouzon's disease, and there was a family history of high-arched palate on the twins' paternal side. Because Crouzon's disease is an uncommon condition and the cloverleaf skull shape is unusual in patients with Crouzon's disease, identical twins with this constellation of deformities must be exceptionally rare.

Airway Obstruction↗

PubMed1991

Craniofacial clefting and sutural dystopia.

Sutural anomalies in conjunction with craniofacial clefting are unusual. A case of median frontal clefting is presented in which there was an absence of a normal metopic suture and replacement by paramedian frontal sutures. The association of an underlying brain anomaly, with attendant surgical difficulties, is noted, as are the radiological techniques of preoperative diagnosis.

Abnormalities, Multiple↗

PubMed1990

High dose eicosapentaenoic acid ethyl ester: effects on lipids and neutrophil leukotriene production in normal volunteers.

1. A 93% pure ethyl ester of eicosapentaenoic acid was investigated for tolerability and biochemical effects on neutrophil leukotriene synthesis and plasma lipoproteins when given in high dose. Six healthy volunteers received 6 g eicosapentaenoic acid ethyl ester daily for 6 weeks, followed by a 4 week wash-out and then 18 g daily for 6 weeks. 2. There was inhibition of neutrophil leukotriene B4 and 5-hydroxyeicosatetraenoic acid synthesis, with no significant differences between low and high dose. 3. There was a dose dependent increase in leukotriene B5 and 5-hydroxyeicosatetraenoic acid acid synthesis. 4. Plasma triglycerides were reduced maximally on 6 g daily, with no greater suppression at 18 g daily. 5. Plasma cholesterol was only suppressed significantly at 18 g daily. 6. The 6 g daily dose was well tolerated but the 18 g daily dose produced diarrhoea and steatorrhoea.

Adult↗

PubMed1981

Multiple features analysis of intervocalic English plosives.

A controlled study involving a multi-feature acoustic analysis of intervocalic English plosives has been conducted for the purpose of evaluating acoustic stop features for automatic stop recognition. Both time-domain and frequency-domain features were measured via computer interaction. The resulting discrete density functions allowed for a comparative evaluation of individual (and in some instance conditional or combined) feature contributions to stop identification. This evaluation consisted of the maximum a posteriori probability of a correct identification of either the voicing mode (voiced or voiceless) or the place of articulation (labial, alveolar, or palato-velar) of a stop independent of the talker or of a limited phonetic context. These features included variations on ten acoustic features for voicing mode identification and seven for place-of-articulation identification. The data base for this study consisted of five male and five female talkers producing all permutations of the stops C epsilon /p,t,k,b,d,g/ and vowels V epsilon /i,e,a,u/ in the sentence frame "please say /h 'CVt/ again." While the results indicate that the acoustic features of burst/formant-onset frequency and voice onset time (VOT) are the two single most salient features for stop identification, several additional features are also shown to provide important redundancy for identification. The often overlooked time-domain features of "double-burst release" and "voicing during stop closure" were found to be particularly useful in providing such redundancy.

Adult↗

PubMed1979

Tempo of spectrum change as a cue in speech-sound discrimination by infants.

Six- to seven-month-old infants were tested on their ability to discriminate among three speech sounds which differed on the basis of formant-transition duration, a major cue to distinctions among stop, semivowel and diphthong classes. The three speech sounds, [see text] were produced in two different ways. The stimuli for one experiment were two-formant synthetic tokens which differed in formant-transition duration. The stimuli for a second experiment was produced with a computer-modification technique which artificially shortened or lengthened the formant-transition portion of a naturally produced [see text], resulting in tokens of [see text]. The discrimination procedure involved visual reinforcement of a head-turn response following a change from a repeating background stimulus to a contrasting stimulus. Infants in both experiments discriminated [see text]; evidence for [see text] discrimination was obtained for the "computer modified" tokens only. These findings are discussed in terms of possible mechanisms underlying speech perception in infancy.

Cues↗

PubMedDate not supplied

Continuing education: do mandates matter?

This study questions the assumption that radiographers lack the motivation to voluntarily participate in continuing professional education. Results of the author's survey of radiographers in 22 Central Florida hospitals--where state law mandates completion of 12 hours of CPE biannually--showed significant differences in participation due to motivational orientation and selected professional, educational and personal characteristics.

Education, Continuing↗

PubMedDate not supplied

Staff development: an alternative to inservice education.

Continuing education may be viewed from two perspectives. Inservice programs are often perceived as externally mandated activities oriented toward the correction of deficiencies. In contrast, the staff development approach involves the shared decision making of the participant and supervisor in the planning, implementation, and evaluation stages of the learning process. Research indicates that the philosophical and managerial perspectives associated with staff development enhance efforts at implementing change.

Education, Medical, Continuing↗