Search PubMed⌕ Search

Biomedical subjects

H Byrne

Publications and source records attributed to H Byrne.

At least 19 recordsLinked to original sources
PubMed1997

Quality of life: perceptions of residential care.

Residents in selected aged care facilities in Australia (n = 185) and New Zealand (n = 44) completed a 56 item quality of life instrument derived and refined through grounded theory. Ten scales were developed from the items. Analysis of variance (ANOVA) indicated that there were no main differences as a function of cohort (Alzheimer's or non-Alzheimer's) or country of residence (Australia or New Zealand). Significant differences emerged as a function of the source of help in completing the instrument. Where nursing staff assisted residents complete the instrument, scoring indicated that residents enjoyed a better quality of life than if the instrument was completed by the resident alone, or with assistance from non-nursing staff and others, including relatives, welfare students and diversional therapists. Nursing staff rather than non-professional nursing staff tended to work more with non-Alzheimer residents when completing the questionnaire. Significant differences were also discovered in the ranking of concerns on the basis of cohort and country of residence.

Aged↗
PubMed1996

Measurement of liver blood flow using oxygen-15 labelled water and dynamic positron emission tomography: limitations of model description.

To date no satisfactory method has been available for the quantitative in vivo measurement of the complex hepatic blood flow. In this study two modelling approaches are proposed for the analysis of liver blood flow using positron emission tomography (PET). Five experiments were performed on three foxhounds. The anaesthetised dogs were each given an intravenous bolus injection of oxygen-15 labelled water, and their livers were then scanned using PET. Radioactivity in the blood from the aorta and portal vein was measured directly and simultaneously using closed external circuits. Time-activity curves were constructed from sequential PET data. Data analysis was performed by assuming that water behaves as a freely diffusible tracer and adapting the standard one-compartment blood flow model to describe the dual blood supply of the liver. Two particular modelling approaches were investigated: the dual-input model used both directly measured input functions (i.e. using the hepatic artery and the portal vein input, determined from the radioactivity detected in the aorta and portal vein respectively) whereas the single-input model used only the measured arterial curve and predicted the corresponding portal input function. Hepatic arterial flow, portal flow and blood volume were fitted from the PET data in several regions of the liver. The resulting estimates were then compared with reference blood flow measurements, obtained using a standard microsphere technique. The microspheres were injected in a separate experiment on the same dogs immediately prior to PET scanning. Whilst neither the single- nor the dual-input models accurately reproduced the arterial reference flow values, the flow values from the single-input model were closer to the microsphere flow values. The proposed single-input model would be a good approximation for liver blood flow measurements in man. The observed discrepancies between the PET and microsphere flow values may be due to the inherent temporal and spatial heterogeneity of liver blood flow. The results presented suggest that adaptation of the standard one-compartment blood flow model to describe the dual blood supply of the liver is limited and other flow tracers have to be considered for quantitative PET measurements in the liver.

Animals↗
PubMed1995

Dementia assessment: to do or not to do?

In this article, the authors summarise the diagnostic investigations that may be used to assess the health status of people with dementia. They express their concern with opposition to the use of the investigations on the grounds of expense and the incapacity of the tests to definitively diagnose Alzheimer's disease. The argument of the paper is that thorough investigation of people with dementia is warranted. Without such assessment, reversible or arrestable conditions that produce symptoms of dementia are not detected or treated. When dementia is diagnosed early, people with the condition and their carers are better prepared to plan and cope and expenses associated with mismanagement of people with some forms of dementia are minimised. The authors conclude that withholding diagnostic investigation of dementia deprives a group of people of the health care to which they are entitled.

Aged↗
PubMed1976

Subcellular localization of cellulases in auxin-treated pea.

Two forms of cellulase, buffer soluble (BS) and buffer insoluble (BI), are induced as a result of auxin treatment of dark-grown pea epicotyls. These two cellulases have been purified to homogeneity. Antibodies raised against the purified cellulases were conjugated with ferritin and were used to localize the two cellulases. Tissue sections were fixed in cold paraformaldehyde-glutaraldehyde and incubated for 1 h in the ferritin conjugates. The sections were washed with continuous shaking for 18 h and subsequently postfixed in osmium tetroxide. Tissue incubated in unconjugated ferritin was used as a control. A major part of BI cellulase is localized at the inner surface of the cell wall in close association with microfibrils. BS cellulase is localized mainly within the distended endoplasmic reticulum. Gogli complex and plasma membrane appear to be completely devoid of any cellulase activity. These observations are consistent with cytochemical localization and biochemical data on the distribution of these two cellulases among various cell and membrane fractions.

Cell Membrane↗
PubMed1975

Purification and characterization of two cellulases from auxin-treated pea epicotyls.

Two forms of beta-1,4-glucan 4-glucanohydrolase (EC 3.2.1.4) were extracted from growing regions of Pisum sativum epicotyls which had been treated with the auxin, (2,4-dichlorophenoxy)acetic acid. One cellulase is buffer-soluble, the other buffer-insoluble but extractable with high salt concentrations. Both enzymes catalyze endohydrolysis of carboxymethylcellulose with the same pH optimum (5.5 to 6.0). They were purified with the use of DEAE-cellulose chromatography, Sephadex gel filtration, and ultrafiltration. They are distinct proteins as characterized by: electrofocusing and disc gel electrophoresis (pI values = 5.2 and 6.9, respectively); mobility in sodium dodecyl sulfate polyacrylamide gels, fractionation on Sephadex, and sedimentation in the ultracentrifuge (mol wt = approximately 20,000 and 70,000, S values 2.63 and 3.73); and immunological properties. The buffer-soluble enzyme tends to dimerize on purification. Amino acid analyses show that the buffer-soluble enzyme is relatively rich in glycine, alanine, and valine and deficient in cystine, tryosine, and phenylalanine compared to the buffer-insoluble enzyme. The two cellulase activities were generated in approximately equal amounts after auxin treatment. Within 5 days their levels had increased at least 100-fold and they constituted about 0.1% of total cellular protein. Present data indicate that one is not derived from the other.

Amino Acids↗
PubMed1975

Regulation and in vitro translation of messenger ribonucleic acid for cellulase from auxin-treated pea epicotyls.

Polysomal RNA was isolated from pea epicotyls treated with (2,4-dichlorophenoxy)acetic acid, and fractionated on oligo(dT)-CELLULOSE TO YIELD POLY(A)-containing RNA. This RNA fraction was translated in a wheat embryo cell-free system and found to have more than 90% of the messenger activity in total polysomal RNA. Immunoprecipitation of the translation product by monospecific antibodies to pea cellulases (beta-1,4-glucan 4-glucanohydrolase, EC 3.2.1.4) indicated that cellulase was synthesized in this system. The immunoprecipitate co-migrated with the buffer-soluble cellulase component in sodium dodecyl sulfate-gel electrophoresis. Buffer-insoluble cellulase was not detected in the in vitro translation products. Fractionation of mRNA from membrane-bound and free polysomes and their subsequent translation indicated preferential synthesis of buffer-soluble cellulase on membrane-bound polysomes. With the above techniques for assaying buffer-soluble cellulase mRNA, a 10-fold increase in the level of this messenger per tissue segment was observed within 48 hours following (2,4-dichlorophenoxy)acetic acid treatment. There was no evidence for pre-existing untranslated message for cellulase in control tissues. Since there was no delay in the appearance of mRNA for cellulase, compared to a 24-hour lag in the increase of cellulase activity, it is suggested that translational as well as transcriptional controls are exerted on the biosynthesis of cellulase in vivo. Analysis of the rates of peptide chain initiation and elongation, both in vivo and in vitro, indicated that peptide chain elongation may be rate-limiting during the lag phase of cellulase development.

2,4-Dichlorophenoxyacetic Acid↗
PubMedDate not supplied

Neonatal transportation: the effects of a national neonatal transportation programme.

BACKGROUND: The transport of critically ill newborns by specialised transport teams has been shown to be associated with a significant improvement in their clinical condition on arrival at the receiving hospital. AIM: To determine if the National Neonatal Transport Programme introduced in 2001 improved clinical condition of newborns at the end of transfer. METHODS: A retrospective study of all 176 patients transported by the National Neonatal Transport Programme between March 2001 and March 2002. RESULTS: Before transfer, 17% of patients were hypothermic, 2% hypoglycaemic and 11% acidotic as were 7%, 3% and 5% respectively at the end of transfer. A review of 172 neonatal transports between 1987 and 1989 revealed that 21% of patients were hypothermic, 13% hypoglycaemic and 20% acidotic at the end of transfer. CONCLUSIONS: The National Neonatal Transport Programme has resulted in improved clinical condition of newborns at the end of transfer when compared to their condition before transfer and compared to outcomes prior to the introduction of the programme.

Critical Illness↗
PubMedDate not supplied

Violence in nursing.

Explore the source record for details and available documents.

Community Health Nursing↗