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Biomedical subjects

M Pitt

Publications and source records attributed to M Pitt.

At least 19 recordsLinked to original sources
PubMed2000

Sequences within the DNA cross-linking patch of sigma 54 involved in promoter recognition, sigma isomerization, and open complex formation.

The bacterial RNA polymerase holoenzyme containing the final sigma(54) subunit functions in enhancer-dependent transcription. Mutagenesis has been used to probe the function of a sequence in the final sigma(54) DNA binding domain that includes residues that cross-link to promoter DNA. Several activities of the final sigma and holoenzyme are shown to depend on the cross-linking patch. The patch contributes to promoter binding by final sigma(54), and holoenzyme and is involved in activator-dependent final sigma isomerization. As part of the final sigma(54)-holoenzyme, some residues in the patch limit basal transcription. Other cross-linking patch sequences appear to limit activator-dependent open complex formation. Deletion of 19 residues adjacent to the cross-linking patch resulted in a holoenzyme unable to respond to activator but capable of activator-independent (bypass) transcription in vitro. Overall results are consistent with the cross-linking patch directing interactions to the -12 promoter region to set basal and activated levels of transcription.

Bacterial Proteins↗
PubMed2000

Amyloidosis of Waldeyer's ring and larynx.

Amyloidosis of the upper aerodigestive tract is relatively rare. A case of localized amyloidosis involving all components of Waldeyer's ring with added laryngeal involvement is described. This has not been previously reported. A literature review of this conditions is presented.

Amyloidosis↗
PubMed1999

Differences in stakeholder expectations in the outcome of physiotherapy management of acute low back pain.

OBJECTIVE: To compare stakeholder expectations of outcome of physiotherapy management of acute low back pain. DESIGN: Observational design using interviews and questionnaires. SETTING: Practice/workplace. STUDY PARTICIPANTS: The study sample was from South Australia. It comprised 74 physiotherapists randomly selected from professional association listings (49.3% response rate), 121 physiotherapy patients (recruited by participating physiotherapists when attending their first physiotherapy treatment for acute low back pain), 21 general practitioners randomly selected from medical practitioner listings in the metropolitan telephone book (36.2% response rate) and 13 third party payers of a total of 16 available insurers in the metropolitan area (82% response rate). MAIN OUTCOME MEASUREMENTS: Stakeholders reported expectations of outcome at the end of the first treatment session and at the completion of the episode of care. RESULTS: There were differences in expectations between stakeholders, as well as between naive and experienced patients. Overall, patients expected symptom relief at the end of the first treatment. Naive patients decided to return for further treatment based on the relationship established with the therapist, whereas experienced patients also expected some advice on their condition during the first contact. Physiotherapists and referrers expected symptom relief and then long-term management strategies to be provided, and third party payers expected cost-efficient management of the condition and patient satisfaction. CONCLUSION: Physiotherapists need to address potential imbalance of consumer knowledge and foster a quality partnership with their patients on the first visit to physiotherapy. Patients who are in pain may not derive full value from information provided in an untimely manner.

Acute Disease↗
PubMed1998

Process modelling and simulation for managing clinical care in the community.

'Care in the Community' is an easy catch phrase but a difficult goal. It is a phrase that addresses a current growth area within health care, and one that comes complete with an impressive array of political, economic and social factors that would seem to support the notion of a continuing trend. Technology, specifically information systems, however, has not been successfully cast in a supporting role. There are many reasons for this lack of success but a major one is the mismatch between the understanding of what is required to support the clinical care processes and the specifications of the current systems supplied. Specifically the interest here is in the use and assessment of two computer science techniques, i.e. process modelling and simulation, as suitable means of capturing and communicating requirements so as to bridge the divided and power differential between users and developers of information systems.

Community Health Nursing↗
PubMed1997

The cioAB genes from Pseudomonas aeruginosa code for a novel cyanide-insensitive terminal oxidase related to the cytochrome bd quinol oxidases.

The structural genes for the cyanide-insensitive terminal oxidase (CIO) of Pseudomonas aeruginosa were sequenced. The locus comprised two open reading frames, cioA and cioB, coding for gene products of 488 and 335 amino acid residues with predicted molecular masses of 54241 and 37016 Da respectively. These genes were encoded by a 2.7 kb transcript and probably comprise an operon. Upstream of a major transcriptional start site is a -10 promoter region and, approximately at nucleotides -50 and +13, there are sequences homologous to the binding site of the transcriptional regulator Anr. The deduced amino acid sequences of CioA and CioB are homologous to the cytochrome bd quinol oxidases of Escherichia coli and Azotobacter vinelandii. However, no cytochrome d-like signals were found in wild-type P. aeruginosa strains. An atypical cytochrome d-like signal was seen under low-aeration growth conditions but only in strains in which the cioAB genes were present on a high-copy-number plasmid. The appearance of these cytochrome d-like signals was not paralleled by a concomitant increase in CIO activity. These data support the hypothesis that the CIO of P. aeruginosa does not contain haem d. This raises the possibility that there is a family of bacterial quinol oxidases related to the cytochrome bd of E. coli that can differ in their haem composition from the E. coli paradigm.

Amino Acid Sequence↗
PubMed1997

Transcatheter embolisation of an enlarging acquired coronary arteriovenous fistula in a heart transplant recipient.

A 50 year old, recent cardiac transplant recipient developed systolic and diastolic murmurs but remained asymptomatic. The cause of the murmurs was not evident at transthoracic echocardiography. During routine left heart catheterisation a left anterior descending artery to right ventricular fistula was evident arising from the distal vessel and presumably acquired during routine endomyocardial biopsy. One year later, the patient remained asymptomatic but the calibre of the left anterior descending artery had increased and there appeared to be poor flow in to the proximal branches. The fistula was successfully treated by percutaneous deployment of two detachable embolisation coils in to the distal left anterior descending artery.

Arteriovenous Fistula↗
PubMed1996

Gas gangrene.

Explore the source record for details and available documents.

Adenocarcinoma↗
PubMed1995

Screening for glaucoma in a Brisbane general practice--the role of tonometry.

OBJECTIVES: (1) To pilot, and evaluate, a tonometry training intervention for general practitioners; (2) to evaluate the efficacy of three types of tonometer (Perkins, Schiotz and Tonopen) in the hands of these general practitioners; (3) to evaluate the predictive value of tonometry in screening for glaucoma in a general practice population; and (4) to evaluate the acceptability of tonometry to general practice patients. DESIGN: After being trained, three general practitioners recruited 73 of their patients over 50 years of age to attend for measurement of intraocular pressure by tonometry. Intraocular pressure was initially measured by an ophthalmologist using the Goldmann applanation tonometer, and then recorded in random order by GPs using three types of tonometer--the Perkins, Schiotz and Tonopen. SETTING: A group general practice in a middle-class suburb in southern Brisbane. OUTCOME MEASURES: (1) Comparison of measurements on the Perkins, Schiotz and Tonopen tonometers with that of the 'gold standard', the Goldmann Applanation tonometer; (2) prevalence of disc and perimetric abnormality suggestive of glaucoma among those patients with increased intraocular pressure; and (3) the acceptability of contact tonometry to general practice patients. RESULTS: There was considerable variability between intraocular values obtained across doctors and across instruments (6% to 95% of values within 4 mm of the 'gold standard'). The Schiotz tonometer provided the most uniform assessment of intraocular pressure across the groups. Nineteen of the 73 patients (26%) had intraocular pressures > or = 21 mmHg using the 'gold standard'. Of these, 18 were followed up with funduscopy, gonioscopy, repeat measurement of intraocular pressure and visual field assessment. Five had persistent elevations of intraocular pressure > or = 21 mmHg on subsequent assessment, and two had mild abnormalities of cup-disc ratio with normal fields on testing with Humphrey computerised perimetry. CONCLUSION: No one hand-held tonometer proved highly accurate in the hands of all three doctors. Even measured optimally, increased intraocular pressure alone was a poor predictor of glaucoma. Of the population screened, two patients (3%) showed evidence of mild cup-disc abnormality requiring follow-up.

Australia↗
PubMed1995

The SAPPHIRE toolkit: an interactive system for the evaluation of primary healthcare computing.

Since April 1992, the SAPPHIRE Project (Systems Accreditation Project in Primary Healthcare Informatics Requirements and Evaluations) has been funded by the Department of Health in the United Kingdom with the goal of providing a framework for the fair and objective evaluation of General Medical Practice (GMP) computer systems [1]. SAPPHIRE is comprised of three 'facets': A comprehensive specification list for GMP information systems. An Assessment methodology to apply the SAPPHIRE specifications. The Integrated Toolkit. The SAPPHIRE Integrated Toolkit has been developed as an interactive computer-based guide for use in the processes of GMP system procurement and education. By integrating the two other 'facets' of SAPPHIRE, it provides a means of matching a set of user-defined specifications against the systems under consideration. This is achieved by enabling the Toolkit user to interactively weight the presented SAPPHIRE specifications to their individual requirements and then match this weighted specification against a database of benchtest results for available systems. The output from this matching process then gives the range of systems which most clearly meet that particular user's needs as well as highlighting the areas where systems fail to meet their defined requirements. Since the SAPPHIRE specification list is a lengthy document comprised of technical language, the Toolkit uses a range of browsing models to display the specifications in accessible ways to the end-user. These browsing models present the specifications in contexts that are familiar to the everyday experience of healthcare employees and hence are easy to access and understand. In addition, the Toolkit offers a 'Quick Route Questionnaire' which accesses a shortcut to the matching process described above. his presentation will demonstrate the main functions of the Toolkit and outline specific scenarios of use. Another area of discussion will be the approach of the SAPPHIRE Project to the problems and issues of computer system evaluation, with reference to the Toolkit in a communications context, assisting in the transfer of understanding between the technical language of system designers and suppliers and the healthcare professional, who may lack computer expertise [2]. The SAPPHIRE Toolkit has a wide range of applications for facilitating the procurement of, and the education processes entailed in, primary healthcare computing. We view the Toolkit as a potential benefit to many aspects of the healthcare profession, including General Practice, Surgery, Healthcare IT Administration, and Information System Supply and Management.

Ambulatory Care Information Systems↗
PubMed1991

Ankle mortise stability in Weber C fractures: indications for syndesmotic fixation.

A Weber type C ankle fracture was sequentially reproduced in 12 cadaver lower extremities and an external rotation torque was applied at each interval. The fractures were then repaired in staged fashion and the rotational stability of the mortise evaluated. Maximum external rotation of the talus within the mortise averaged 7.7 degrees in the intact ankle and increased by 311% to 31.8 degrees after creation of a Weber C injury. Rigid fixation of the fibular fracture restored 32% of the rotational stability, whereas isolated fixation of the medial malleolus reconstituted 57%. Fibular fixation combined with a syndesmotic screw restored 51% of original stability, and the addition of medial malleolar fixation improved stability to 101%. Bimalleolar fixation without a syndesmotic screw yielded 73% of the original rotational stability. The results of this study suggest that when rigid medial and lateral osteosynthesis can be achieved, syndesmotic fixation may not be necessary.

Ankle Injuries↗
PubMed1986

Bone reinforcement lines in chronic adult osteopenia: a hypothesis.

Although linear bands of increased radiodensity have been described in the tubular bones of children, similar but less often reported structures are frequent in the osteopenic skeleton of middle-aged and elderly patients. In this study, the radiology, pathology, and histology of osseous bands in the mature skeleton were analyzed in 20 cadavers, 29 macerated ancient and modern bone specimens, and 100 recent radiographs. These radiodense areas represent complete or incomplete, horizontally or obliquely oriented bars composed of compact lamellar bone. Although their precise pathogenesis is not clear, they are associated with long-standing (vs. acute) osteopenia. In some instances, bone bars appear to be formed during skeletal growth, remain hidden in the adult because of adjacent trabeculae, and are unmasked by osseous resorption. In other instances, bone bars appear to be formed initially in the mature skeleton as a response to chronic mechanical stress and, as such, are not identical with growth recovery lines observed in children. They are more accurately considered bone reinforcement lines.

Adult↗
PubMed1985

Computed tomography and automated image analysis of prehistoric femora.

Non-invasive characterization of limb bone cross-sectional geometry would be useful for biomechanical analyses of skeletal collections. Computed tomography (CT) is potentially the method of choice. Additionally, CT images are suitable for automated analysis. CT is here shown to be both accurate and precise in the analysis of cross-sectional geometry of prehistoric femora. Beam hardening artifacts can be reduced by using a water bath. As the availability of CT for research increases, both bone density and geometry could be determined simultaneously with this method.

Autoanalysis↗
PubMed1985

Vitamin D metabolites in adolescents and young adults with cystic fibrosis: effects of sun and season.

To assess mineral metabolism in patients with cystic fibrosis and to study the effects of season and sunlight exposure on generation of vitamin D metabolites, we quantified serum levels of calcidiol and calcitriol, other measures of bone metabolism, and radiographic bone mass in 20 adolescents and young adults with CF and 20 age-matched normal volunteers. Levels of calcidiol were lower in patients with CF than in controls and lower in Massachusetts than in Arizona in both study groups. Controls in Arizona had higher (P less than 0.05) levels of calcitriol than in Massachusetts throughout the year. All control subjects in both states had higher levels of calcitriol than did patients with CF. Patients in Massachusetts had significantly lower levels of calcitriol in winter than in summer. Summer levels of calcitriol in CF were significantly higher in Massachusetts than in Arizona; during winter, lower levels were found in Massachusetts than in Arizona. Mean bone density in patients with CF was 88% and 89% of normal American standards in Massachusetts and Arizona, respectively. These data indicate a seasonal, sunlight-related influence on levels of vitamin D metabolites in patients with CF receiving approximately 1000 IU vitamin D per day. Older patients with CF with progressively diminishing sunlight exposure may be at increased risk for development of osteopenia. The detected radiographic abnormalities of bone mineralization may also be related to malabsorptive deficiencies of calcium and phosphorus.

25-Hydroxyvitamin D 2↗