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P Matthews

Publications and source records attributed to P Matthews.

At least 19 recordsLinked to original sources
PubMed2005

River basins: the environmental engines to keep us all running.

The importance of clean water, good sanitation and a healthy environment demands better management of planning, control and regulation with catchments increasingly being the administrative basis of regional management. It then makes eminent sense from a theoretical and practical point of view to use the basin as the administrative unit to model and administer an integrated environmental protection regime.

Conservation of Natural Resources↗
PubMed2004

Medial septal lesions mimic effects of both selective dorsal and ventral hippocampal lesions.

Electrolytic medial septal (MS) lesions, which depleted acetylcholinesterase staining in both dorsal and ventral hippocampus, produced a constellation of behaviors, combining aspects of both selective dorsal and ventral hippocampal lesion effects. MS lesions impaired spatial working memory on the T maze, thus resembling the effects of dorsal hippocampal lesions. In addition, MS lesions reduced anxiety during successive alleys (a modified form of the elevated plus-maze), social interaction, and hyponeophagia tests. MS lesions also reduced postshock freezing. These effects more closely resemble those of ventral hippocampal lesions. Therefore, the effects of electrolytic MS lesions derive from the resulting combined deafferentation of dorsal and ventral hippocampal regions, suggesting that previously reported effects of cytotoxic dorsal hippocampal lesions are unlikely to be due to a demyelination of fibers of passage coursing through the septal pole.

Animals↗
PubMed2004

Sustainable biosolids--welcomed practice through community partnership and the consequential economic benefits.

Technically, most people agree that conserving soil organic matter and completing nutrient cycles by applying animal manures, treated organic wastes and biosolids to land is the most sustainable option in the majority of situations. It is also generally the least expensive. There has been a huge amount of research into the hazards, and this has concluded that the risks can be managed to acceptable levels. But there has been insufficient attention to communicating this knowledge, as so often in the scientific and technological arena. Perception is reality. Nowadays compliance with regulations (whilst essential) is not enough; public and stakeholder attitudes can be of decisive importance. Sometimes policy-makers speculate what public attitudes might be without really asking them. This paper will describe an initiative to create a partnership open to anybody with an interest in the use of organic materials on land to develop consensus on good practice and to share knowledge. It summarises an attitude survey of more than 140 organisations, which was then debated at a workshop in July 2002. The conclusion from this study was that all parties considered a partnership is essential to share knowledge, build mutual trust and agree practices that are welcomed by all in the food chain. The paper will describe the steps to establishing a partnership organisation, its aims and objectives, the work to date and the plans for the future. The Environment Agency considers this very important and has largely funded the work to date. The consequences of failing to establish welcomed practices would be loss of the facility to use organic resources on land.

Conservation of Natural Resources↗
PubMed2003

Comparison of Agrobacterium-mediated transformation of four barley cultivars using the GFP and GUS reporter genes.

Experiments were conducted to produce transgenic barley plants following infection of immature embryos with Agrobacterium tumefaciens. Transformed callus was obtained using hygromycin resistance as a selectable marker and either green fluorescent protein (GFP) or beta-glucuronidase (GUS) as a reporter. Significantly reduced plant transformation frequencies were obtained with the GFP gene compared to GUS. However, GFP proved to be an excellent reporter of early transformation events and was used to compare four barley cultivars for efficiency in two phases of transformation: the generation of stably transformed barley callus and the regeneration of plantlets from transformed callus. Transformed callus was generated at a high frequency (47-76%) in all four cultivars. Regeneration of transformed plantlets was also achieved for all four cultivars although the frequency was much higher for Golden Promise than for the other three genotypes, reiterating that genotype is an important determinant in the regenerative ability of barley. This study has demonstrated for the first time that Agrobacterium-mediated transformation can be used to transform the Australian cultivars Sloop and Chebec.

Agrobacterium tumefaciens↗
PubMed2001

Stability of Adderall in extemporaneously compounded oral liquids.

The short-term stability of Adderall in three extemporaneously compounded oral liquids was studied. Three suspensions of Adderall 1 mg/mL were prepared from commercially available 10-mg Adderall tablets with Ora-Sweet, Ora-Plus, and a 1:1 mixture of Ora-Sweet and Ora-Plus. Each suspension was stored in the dark in a stability chamber at 25 degrees C and 60% relative humidity for 30 days. The stability of the active drug (a mixture of levoamphetamine and dextroamphetamine salts) in each of the three vehicles was determined immediately after preparation and at 10, 20, and 30 days by using gas chromatography-mass spectrometry (GCMS). No significant changes in concentrations of either amphetamine isomer occurred during the 30-day study period. Visual inspection of samples revealed no changes in color or odor. Extemporaneously compounded liquid oral formulations of Adderall 1 mg/mL in Ora-Sweet, Ora-Plus, or a 1:1 mixture of Ora-Sweet and Ora-Plus were stable for at least 30 days at 25 degrees C and 60% relative humidity.

Administration, Oral↗
PubMed2001

Telomerase activity and telomere length in thyroid neoplasia: biological and clinical implications.

Despite several recent studies, the biological status and clinical relevance of telomerase expression in tumours derived from the thyroid follicular cell remain controversial. This study has analysed a series of normal, benign, and malignant thyroid samples using two novel approaches: the use of purified epithelial cell fractions to eliminate false-positives due to telomerase-positive infiltrating lymphocytes; and the simultaneous measurement of telomere length to provide a clearer interpretation of telomere dynamics in thyroid neoplasia. The data obtained support the prediction that the epithelial component of non-neoplastic thyroid and of follicular adenomas is telomerase-negative, any positive results being explicable by lymphocyte infiltration. In contrast, many malignant tumours, both follicular and papillary, were telomerase-positive. However, serial dilution of extracts indicated a wide spectrum of activity in these cancers, possibly related to variation in the proportion of telomerase-positive cells. Furthermore, an unexpectedly high proportion were telomerase-negative, a finding which was not explicable by technical problems such as TRAP (telomeric repeat amplification protocol) assay sensitivity. Many of these apparently telomerase-negative tumours had abnormally long telomeres. Correlation of telomerase and telomere length data suggests that thyroid cancers fall into three biological groups: telomerase-positive lesions, consistent with the conventional model of telomere erosion followed by telomerase reactivation; telomerase-negative tumours, which maintain telomere length by a mechanism independent of telomerase; and telomerase-negative tumours which are still undergoing telomere erosion and may therefore be composed of mortal cancer cells. From a clinical standpoint, it is concluded that telomerase detection on unfractionated tissue, such as fine needle aspirates, is of no value as a marker of malignancy in follicular lesions, due to both low sensitivity and specificity.

Adenoma↗
PubMed2001

Semi-implantable electromagnetic middle ear hearing device for moderate to severe sensorineural hearing loss.

Despite the many improvements in hearing aid technology, conventional hearing aids continue to have significant limitations, which has led to increased interest in implantable hearing devices. The SOUNDTEC Direct Drive Hearing System for moderate to moderately severe sensorineural hearing loss is one such device. In this article the authors present results on five individuals enrolled in a Food And Drug Administration Phase I feasibility study.

Auditory Threshold↗
PubMed2001

An audit of "equivocal" (C3) and "suspicious" (C4) categories in fine needle aspiration cytology of the breast.

We have audited the frequency of use and outcome of the "equivocal/atypia probably benign" (C3) and "suspicious of malignancy" (C4) category for breast cytology in our Unit. A total of 14 935 cytological specimens were reported by at least one of the three pathologists with a special interest in breast pathology, according to five categories of the NHSBSP guidelines for cytology reporting, 1992; 3.7% (555 cases) and 3.9% (587 cases) of cases were classified as equivocal (C3) and suspicious (C4), respectively, giving a total rate (C3 + C4) of 7.6%. Of the C3 cases, 68% were subsequently benign and 32% were malignant. Of the C4 cases, 19% were subsequently benign and 81% malignant. The commonest benign lesions in both categories were fibroadenomas (7.6% of C3 and 19.8% of C4), fibrocystic change (14.3% of C3 and 12.5% of C4), radial scars (6.2% of C3 and 10.4% of C4) and papillomas (6.2% of C3 and 6.3% of C4). Of the malignant lesions (particularly those classified as C3), a high proportion were low grade or special type cancers. The categories of atypia probably benign (C3) and suspicious of malignancy (C4) in breast cytology provide a strategy for classification of problematic or uncertain cases; this maintains the predictive value of the benign (C2) and malignant (C5) categories, and allows separation of these difficult cases into clinically useful groups with differing probabilities of malignancy.

Biopsy, Needle↗
PubMed2001

Clinical implications of telomerase detection.

In 1994 a sensitive method for the detection of telomerase was described. This assay, which was based on the polymerase chain reaction, suggested that telomerase activity was associated with immortal and cancer cells. Since then more than a thousand studies have documented the expression and activity of the enzyme in diseased tissues, primarily tumours. This review gives an overview of the biological significance of telomerase expression and methods for detecting its activity. This is followed by an organ system-based discussion of expression in normal tissues and disease states. We finish with speculation as to the future role of telomerase detection in diagnostic histopathology.

Cellular Senescence↗
PubMed2001

Early clinical results: SOUNDTEC implantable hearing device phase II study.

OBJECTIVE: To assess the safety and efficacy of a new semi-implantable electromagnetic hearing device, the SOUNDTEC Direct Drive Hearing System (DDHS), and to compare its performance with that of subjects' previously worn, optimally fit hearing aids. Preliminary results for the first 10 subjects are presented. STUDY DESIGN: The protocol specified in the Investigational Device Exemption is used in this ongoing FDA phase II 100-subject multicenter clinical trial. METHODS: For baseline, each subject is tested wearing his or her own optimally fit hearing aid in the ear to be implanted. Six-month postoperative outcome measures using the SOUNDTEC DDHS are compared with the baseline. Multiple objective and subjective outcomes (as listed under Results) were measured. RESULTS: When compared with the subjects' optimally fit hearing aids, the SOUNDTEC DDHS provided an average improvement of 52% in functional gain (250-6000 Hz), 22% in aided thresholds, 3.8% for speech discrimination in quiet, 17% for speech in noise, 13.1% in articulation index scores, 28% in aided benefit, 27.3% in sound quality of speech, and a 16.7% increase in overall subject satisfaction. In addition, with the SOUNDTEC DDHS, subjects reported absence of acoustic feedback, little or no occlusive effects, and more natural sound perception. CONCLUSION: Analysis of data on the first 10 subjects using the SOUNDTEC DDHS indicates positive outcomes regarding safety and efficacy, although the small sample size is not sufficient to permit valid statistical inferences to be drawn from our preliminary data. Results also demonstrate improvement in performance compared with the subjects' optimally fit hearing aids and an improvement in quality of life as demonstrated by objective and subjective tests and measures.

Aged↗
PubMed2001

Sexually transmitted infections in primary care: a need for education.

General practitioners and practice nurses require the clinical skills that will enable them to detect sexually transmitted infections in the context of a shift to having no, or insidious symptoms. They need to be able to confirm the diagnosis and have clear models for management and referral. Primary care and genitourinary medicine need to work more closely together to increase mutual understanding and clarify the issues which surround referral and attendance. Sexual health risk assessment through the investigation of sexual history is a helpful way forward in both differential diagnosis and in targeting sexual health promotion and care. Many aspects of these clinical skills are specific to the primary care context. There is a need for improved undergraduate, postgraduate, and in-service training. Multidisciplinary educational approaches are ideal for the subject of sexual health. Primary care groups offer a potential way forward to help develop quality in primary care and some are developing health improvement programmes that aim to address sexual health issues.

Ambulatory Care↗
PubMed2001

The filter system for tertiary treatment of sewage effluent by land application--its performance in a subtropical environment.

FILTER is an innovative, CSIRO developed system for treating effluent using high rate land application and subsequent effluent recapture via a closely spaced, subsurface drainage network. We report on the summer performance of a FILTER system established in a subtropical environment on a relatively impermeable swelling clay soil underlain by a deep regional water table. Using secondary treated sewage effluent, the FILTER system produced effluent of tertiary nutrient standards (< or = 5 mg/L TN; < or = 1 mg/L TP), with salinity levels suitable for subsequent irrigation reuse (EC < or = 2.5 dS/m). Removal of faecal coliforms was considerably less effective. The hydraulic loading rate achieved was about two and a half times large than conventional irrigation demand, but this was associated with high deep percolation losses (c 3 mm/day). Comparisons are made with the original FILTER system developed and tested by Jayawardane et al. in temperate Australia. Suggestions are made for modifications to, and further testing of FILTER in a subtropical environment.

Australia↗
PubMed2000

Molecular typing of methicillin-resistant Staphylococcus aureus by pulsed-field gel electrophoresis: comparison of results obtained in a multilaboratory effort using identical protocols and MRSA strains.

Pulsed-field gel electrophoresis (PFGE) has become the gold standard of molecular methods in epidemiological investigations. In spite of its high resolving power, use of the method has been hampered by inadequate laboratory-to-laboratory reproducibility. In the project described here we have addressed this problem by organizing a multilaboratory effort in which the same bacterial strains (subtype variants of the Iberian and Brazilian methicillin-resistant Staphylococcus aureus--MRSA--clones) were analyzed by twenty investigators in thirteen different laboratories according to an indentical protocol, which is reproduced here in detail. PFGE patterns obtained were analyzed at a central laboratory in order to identify specific technical problems that produced substandard macrorestriction patterns. The results including the specific technical problems and their most likely causes are described in this communication. Also listed are seven major epidemic clones of MRSA which have been characterized by molecular fingerprinting techniques and the prototypes of which have been deposited at the American Type Culture Collection, from where they will be available for interested investigators for the purpose of typing MRSA isolates. It is hoped that this communication will contribute to the improvement of the reproducibility and technical/aesthetic quality of PFGE analysis.

Bacterial Typing Techniques↗
PubMed2000

Pathology of early-onset Alzheimer's disease cases bearing the Thr113-114ins presenilin-1 mutation.

Most cases of familial presenile Alzheimer's disease are caused by mutations in the presenilin-1 (PSEN-1) gene, most of these mutations being missense mutations. A mutation in the splice donor site of intron 4 of PSEN-1 has been described recently which results in aberrant splicing of PSEN-1 mRNA, causing insertion of an additional amino acid, Thr113-114ins, into the protein. We studied the neuropathology of four cases bearing this mutation in an attempt to clarify the pathology of this hereditary form of Alzheimer's disease and to determine whether it differs from other familial forms of the disease. The disease presented as a progressive cognitive decline, myoclonus and seizures developing later in the disease, a feature common to PSEN-1-linked Alzheimer's disease. The course of the disease was relatively rapid, death occurring approximately 6 years after onset. Pathology in the intron 4 cases demonstrated a severe Alzheimer's disease pathology with abundant deposition of ss-amyloid (Ass) 1-42 senile plaques and the formation of neurofibrillary tangles. Amyloid angiopathy was present in these cases and was readily demonstrated by Ass 1-40 staining, particularly in the cerebellum. Cases with the intron 4 mutation appear clinically and pathologically similar to other cases of early-onset Alzheimer's disease bearing PSEN-1 mutations.

Adult↗
PubMed2000

Planning for successful outcomes in the new millennium.

The complexity of the health care environment will increase in the next millennium. Organizations must adopt an approach of selecting outcomes management solutions that are focused on data capture, analysis, and comparative reviews and reporting. They must decisively and creatively implement, in a phased approach, integrated solutions from existing robust systems, while considering future systems targeted for implementation. Outcomes management solutions must be integrated with the organization's information systems strategic plan. The successful organization must be able to turn business-critical data into information that supports both business and clinical decision-making activities. In short, health care organizations will have to become information-driven.

Benchmarking↗
PubMed2000

Leveraging technology for success.

Many new information systems, technologies, and inventions promise significant benefit and value. Balancing the ever-increasing technology demands and their related expense with provision of high quality cost-effective patient care is one of today's significant organizational challenges. When appropriately deployed, Information Technology can support organizations in achieving their competitive leverage, market position, quality patient care, and efficient operations. This article presents an overview of the impact of new and emerging technologies, and suggests ways organizations can successfully leverage information systems and technology.

Community Participation↗
PubMed2000

Crafting a new vision for compliance.

The healthcare industry has been overwhelmed with year 2000 activities while providers continue to move toward the goal of a computer-based patient medical record. The ultimate goal remains to provide seamless access to critical patient, clinical, administrative, and financial data and support a cohesive approach throughout the continuum of care. Until recently, compliance and standards have not been at the forefront of provider efforts and have even met with resistance. The view of compliance must move up to the next level: an organizational and management tool. This article discusses how providers may begin to develop a compliance model that supports business strategies and functions as well as information management programs.

Benchmarking↗