PubMed Health⌕ Search

Biomedical subjects

F Richardson

Publications and source records attributed to F Richardson.

At least 19 recordsLinked to original sources
PubMed2001

Effect of glucocorticoid therapy on energy intake in children treated for acute lymphoblastic leukemia.

Despite a widespread belief that glucocorticoid therapy is associated with positive energy balance and excess weight gain there is a dearth of quantitative evidence about its effects and the underlying mechanisms of any effects. The primary aim of the present study was to quantify the effect of dexamethasone and prednisone treatment on energy intake in children treated for childhood acute lymphoblastic leukemia. A secondary aim was to test for differences in excess weight gain between patients treated using the 2 glucocorticoids. We measured energy intake in 26 patients (mean +/- SD age, 6.3 +/- 2.3 yr) during a 5-d period "on" steroids and again in the week before steroid treatment. Changes in body mass index from diagnosis to 1 and 2 yr postdiagnosis were expressed as SD scores. Steroid treatment was associated with a significant increase in energy intake of approximately 20% (mean paired difference, 1.7 MJ/d; SD, 2.8; 95% confidence interval, 0.7-2.8 MJ/d), with no significant difference between the 2 steroids. The mean change in body mass index SD score was +0.38 (SD, 1.10; P < 0.05) to 1 yr and +0.68 (SD, 1.38; P < 0.05) to 2 yr, with no significant difference between the 2 groups of patients. Glucocorticoid treatment in childhood acute lymphoblastic leukemia increases energy intake markedly, and this effect contributes to the excess weight gain and obesity characteristic of patients being treated for acute lymphoblastic leukemia.

Body Mass Index↗
PubMed1999

Navigating ambulatory referral: a standardized process.

Significant funding and structure changes to healthcare in Ontario in the mid-90's led The Hospital for Sick Children in Toronto to examine patient referral processes. In an effort to streamline access and encourage more appropriate referrals, the hospital tested and implemented three major changes. This article outlines these changes using the PDSA (Plan, Do, Study, Act) improvement framework and summarizes the results from this project.

Ambulatory Care↗
PubMed1996

The effects of peroxisome proliferators on protein abundances in mouse liver.

We have investigated the effects of five peroxisome proliferators (PPs : clofibric acid, DEHP, WY14,643, nafenopin, and LY171883) on the abundances of a large number of proteins in the livers of treated mice at 5- and 35-day time points. LY171883 was investigated at a range of doses, and one of its close structural analogs that is not a peroxisome proliferator (LY163443) was included as a negative control compound. Liver samples were analyzed by quantitative 2-D electrophoresis. Data for a selected set of 107 liver protein spots that respond strongly to at least one of the test compounds was subjected to principal component analysis to search for global protein pattern changes. The first component (PC1) accounted for 51% of the total data variance and was identified as a global measure of peroxisome proliferation by its correlation with enzymatic peroxisomal beta-oxidation. Component PC2 (7%) separated 5- and 35-day exposures, and PC3 (5%) separated groups treated with LY163443 from the rest. We used PC1 as a surrogate for equivalent dose in order to examine the effects of diverse compounds, with widely differing potencies, on a common scale. Analyzed in this way, the data indicate that all the peroxisome proliferators tested produce effects over wide time and dose ranges that fall on or near a single curve. Examination of specific protein responses showed that many proteins individually show a unified response curve, but that curves for different proteins were different. In particular, it appears that some constitutive proteins showing modest inductions with a high dose plateau (such as cytosolic epoxide hydrolase) are inducible at lower doses than some proteins showing very strong, nonplateaued inductions (such as the 80-kDa peroxisomal bifunctional enzyme). The results provide support for a unified receptor-based mechanism controlling the main PP response, but demonstrate that individual responsive genes can show quite different dose-response curves.

Acetophenones↗
PubMed1987

Speaking rate of adventitiously deaf male cochlear implant candidates.

No objective group data on speaking rate or speaking duration have been reported on the speech of adventitiously profoundly hearing-impaired adults. Results of the present study showed that speaking rate, i.e., number of syllables per second, was significantly slower and speaking duration was significantly longer for 25 adventitiously profoundly hearing-impaired adult male cochlear implant candidates than for 10 normal-hearing control subjects. The factors of length of time since onset of profound hearing loss and hearing aid use did not significantly affect speaking rate. Based on these objective data, a rationale and method are presented for aural rehabilitation of the profoundly hearing-impaired who exhibit speaking rate abnormalities.

Adult↗
PubMed1987

Voice intensity of prospective cochlear implant candidates and normal hearing adult males.

Voice intensity in 19 prospective cochlear implant candidates, all adventitiously profoundly sensorineurally deaf adult males, was investigated. For the first time with objective data, it was shown that such deaf subjects spoke with significantly increased voice intensity and with greater intensity fluctuations than normal hearing male speakers. Neither length of time of profound deafness nor history of hearing aid use significantly affected voice intensity. Based on quantitative data, rehabilitation of voice intensity problems in the adventitiously deaf is indicated.

Aged↗
PubMed1986

Vibrotactile stimulation for the adventitiously deaf: an alternative to cochlear implantation.

Acoustic correlates of the prosodic features identifying English contrastive stress, ie, fundamental frequency (Fo), duration and intensity, and listener perceptions were investigated in a profoundly adventitiously deaf subject (D) pre/postvibrotactile stimulation, and in an age-peer normally-hearing person as a control (N). Stimuli were a group of general American English words in which a change of function from noun to verb was associated with a shift of stress from initial to final syllable, eg, CON'test vs conTEST'. Prior to vibrotactile stimulation, D was unable to produce contrastive stress correctly. Only final syllable intensity differences were noted, but proved to be inadequate cues for contrastive stress. Vibrotactile stimulation resulted in changes, specifically significantly higher Fo for initial stressed vs unstressed syllables, significantly louder intensity for final stressed vs unstressed syllables, and significantly longer duration for final stressed vs unstressed syllables. Perceptually, listeners judged D's contrastive stress placement as always occurring on the final syllable previbrotactile stimulation and as 78% correct postvibrotactile stimulation. N's contrastive stress placement was always correct. It was concluded that use of vibrotactile stimulation enhanced D's production and resulted in listeners' perceptions of correct prosody.

Cochlear Implants↗
PubMed1986

Reacquisition of contrastive stress in an adventitiously deaf speaker using a single-channel cochlear implant.

Acoustic correlates of contrastive stress, i.e., fundamental frequency (F0), duration, and intensity, and listener perceptions of stress, were investigated in a profoundly deaf subject (RS) pre/post single-channel cochlear implant and longitudinally, and compared to the overall patterns of age-peer profoundly deaf (JM) and normally hearing subjects (DL). The stimuli were a group of general American English words in which a change of function from noun to verb is associated with a shift of stress from initial to final syllable, e.g., CON'trast versus conTRAST'. Precochlear implant, RS was unable to produce contrastive stress correctly. Hearing one day post-stimulation resulted in significantly higher F0 for initial and final stressed versus unstressed syllables. Four months post-stimulation, RS maintained significantly higher F0 on stressed syllables, as well as generalization of significantly increased intensity and longer syllable duration differences for all stressed versus unstressed syllables. Perceptually, listeners judged RS's contrastive stress placement as incorrect precochlear implant and as always correct post-cochlear implant. JM's contrastive stress was judged as 96% correct, and DL's contrastive stress placement was 100% correct. It was concluded that RS reacquired all acoustic correlates needed for appropriate differentiation of contrastive stress with longitudinal use of the cochlear implant.

Acoustic Stimulation↗