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Biomedical subjects

A Walker

Publications and source records attributed to A Walker.

At least 109 records · Page 6Linked to original sources
PubMed2000

Isolation and characterization of 23 carbofuran-degrading bacteria from soils from distant geographical areas.

The aim of this work was to isolate, identify and type carbofuran-degrading bacteria from two geographically distant soils. Restriction Fragment Length Polymorphism (RFLP) patterns of the 16S rRNA gene and partial 16S rRNA sequence analysis were used to classify the 23 isolates obtained. Nine of them showed high similarity to Pseudomonas strains, seven showed similarity to the Flexibacter/Cytophaga/Bacteroides group and the remainder showed similarity to other bacterial genera. Isolates within the same group were sub-typed by comparing partial 16S rRNA sequences and SDS-PAGE analysis of their total protein profiles. Many of the UK isolates showed similarity to the Pseudomonas genera, while most of the Greek isolates showed similarity to the Flexibacter/Cytophaga/Bacteroides group. Only two Chrysobacterium strains isolated from both the UK and Greek soils were identical.

Bacteria↗
PubMed2000

It's a knockout: survey of the management of avulsed teeth.

Avulsion of a tooth is a not uncommon childhood injury, with up to 16% of dental injuries involving the loss of a tooth. Although this is an apparently 'minor' injury, for a child there may be long-term psychological and treatment problems. Correct advice in the early stages of this injury, and the recognition that prompt treatment may allow a tooth to be successfully reimplanted are vital in the management of these injuries. Often, nursing staff in the accident and emergency or paediatric department may be asked for advice either professionally or informally, and can influence the long-term dental health for these patients. This paper looks at the knowledge of parents and healthcare professionals in the management of these injuries.

Adolescent↗
PubMed2000

Mathematic modeling of forces associated with shoulder dystocia: a comparison of endogenous and exogenous sources.

OBJECTIVE: A mathematic model was developed to estimate the compressive pressure on the fetal neck overlying the roots of the brachial plexus by the symphysis pubis during a shoulder dystocia event. The induced pressure was calculated for both exogenous (clinician applied) and endogenous (maternal and uterine) forces during the second stage of labor. STUDY DESIGN: Intrauterine pressure and clinician-applied force data were taken from the existing literature. A free-body diagram was generated and equilibrium equations were used to calculate the contact pressure between the base of the fetal neck and the symphysis pubis during a shoulder dystocia event. RESULTS: Clinician-applied traction to the fetal head (exogenous force) led to an estimated contact pressure of 22.9 kPa between the fetal neck and the symphysis pubis. In contrast, uterine and maternal expulsive efforts (endogenous forces) resulted in contact pressures that ranged from 91.1 to 202.5 kPa. The estimated pressures resulting from endogenous forces are 4 to 9 times greater than the value calculated for clinician-applied forces. CONCLUSION: Neonatal brachial plexus injury is not a priori explained by iatrogenically induced excessive traction. Spontaneous endogenous forces may contribute substantially to this type of neonatal trauma.

Brachial Plexus↗
PubMed2000

Distributional impact of higher patient contributions to Australia's Pharmaceutical Benefits Scheme.

This paper uses NATSEM's Pharmaceutical Benefits Model to analyse the effects of a hypothetical 25 per cent rise in patient contributions to prescribed medicines under Australia's Pharmaceutical Benefits Scheme (PBS). The model, based on microsimulation techniques, is able to provide a much broader range of outcomes information, at a much greater level of detail, than is possible with traditional methods. Higher patient contributions are analysed in terms of their impact on the government to patient split in PBS costs, as well as the distribution of such costs across age groups, family incomes, family types and 36 prescribed medicine types. Also considered are changes in the shares of family disposable incomes spent on prescribed drugs arising from the higher patient contributions.

Adolescent↗
PubMed2000

Two new mechanisms of macrolide resistance in clinical strains of Streptococcus pneumoniae from Eastern Europe and North America.

Resistance to macrolides in pneumococci is generally mediated by methylation of 23S rRNA via erm(B) methylase which can confer a macrolide (M)-, lincosamide (L)-, and streptogramin B (S(B))-resistant (MLS(B)) phenotype or by drug efflux via mef(A) which confers resistance to 14- and 15-membered macrolides only. We studied 20 strains with unusual ML or MS(B) phenotypes which did not harbor erm(B) or mef(A). The strains had been isolated from patients in Eastern Europe and North America from 1992 to 1998. These isolates were found to contain mutations in genes for either 23S rRNA or ribosomal proteins. Three strains from the United States with an ML phenotype, each representing a different clone, were characterized as having an A2059G (Escherichia coli numbering) change in three of the four 23S rRNA alleles. Susceptibility to macrolides and lincosamides decreased as the number of alleles in isogenic strains containing A2059G increased. Sixteen MS(B) strains from Eastern Europe were found to contain a 3-amino-acid substitution ((69)GTG(71) to TPS) in a highly conserved region of the ribosomal protein L4 ((63)KPWRQKGTGRAR(74)). These strains formed several distinct clonal types. The single MS(B) strain from Canada contained a 6-amino-acid L4 insertion ((69)GTGREKGTGRAR), which impacted growth rate and also conferred a 500-fold increase in MIC on the ketolide telithromycin. These macrolide resistance mechanisms from clinical isolates are similar to those recently described for laboratory-derived mutants.

Amino Acid Sequence↗
PubMed2000

Survey of the use of rapid sequence induction in the accident and emergency department.

OBJECTIVES: To determine the current position regarding the use of rapid sequence induction (RSI) by accident and emergency (A&E) medical staff and the attitudes of consultants in A&E and anaesthetics towards this. METHODS: A questionnaire was designed that was distributed to consultant anaesthetists and A&E physicians in hospitals receiving over 50,000 new A&E patients per year. RESULTS: A total of 140 replies were received (a response rate of 72%). The breakdown of results is shown. There was wide difference of opinion between anaesthetists and A&E consultants as to who performs RSI at present in their A&E departments, however two thirds of anaesthetists thought A&E staff with appropriate training and support should attempt RSI either routinely or in certain circumstances. CONCLUSIONS: A&E staff in several hospitals routinely undertake RSI and the majority of A&E consultants thought that RSI would be undertaken by A&E staff if an anaesthetist were unavailable. There is disagreement regarding the length of anaesthetic training required before A&E medical staff should undertake RSI.

Anesthesiology↗
PubMed2000

Measuring the costs and benefits of heart disease monitoring.

OBJECTIVE: To evaluate the costs and benefits of alternative systems of coronary heart disease monitoring in Scotland. DESIGN: An option appraisal was conducted to evaluate the costs and benefits of implementing a coronary heart disease monitoring system. This involved a review of existing Scottish datasets and relevant reports, specification of options, definition and weighting of benefit criteria by key stakeholders, assessment of options by experts, and costing of options. The options were assessed by 33 stakeholders (grouped as cardiologists, patient representatives, general practitioners, public health physicians, and policy makers), plus 13 topic experts. SETTING: Scotland (population 5.1 million). RESULTS: Between group mean benefit weights were: mortality rates and case fatality (10.6), quality of life (9.8), patient function (8.8), hospital activity (7.8), primary care activity (9.25), prescribing (5.72), socioeconomic impact (4.0), risk factors (7.4), prevalence (5.0), incidence (6.0), case registration (6.82), international comparability (4.2), breadth of coverage (8.8), and frequency (5.8). Differences between group weights were significant for prevalence (p = 0.048) and international comparability (p = 0.032). Four monitoring options were identified: a community epidemiology model, based on MONICA (monitoring trends and determinants in cardiovascular disease) study methodology applied to a series of eight representative communities, had the highest benefits, at an average annual discounted cost of approximately pound 360,000; models based on the Australian cardiovascular disease monitoring scheme and on enhanced routine data offered fewer benefits at discounted average annual costs ranging from pound 165,000 to pound 195,000; finally, a coronary heart disease registry modelled on the Scottish Cancer Registry scheme would have had fewer benefits and substantially higher costs than the other options. CONCLUSIONS: The most beneficial coronary heart disease monitoring system is the community epidemiology model, based on MONICA methodology. Option appraisal potentially offers an explicit and transparent methodology for evidence based policy development.

Coronary Disease↗
PubMed2000

Altered focal adhesion regulation correlates with cardiomyopathy in mice expressing constitutively active rac1.

The ras family of small GTP-binding proteins exerts powerful effects upon cell structure and function. One member of this family, rac, induces actin cytoskeletal reorganization in nonmuscle cells and hypertrophic changes in cultured cardiomyocytes. To examine the effect of rac1 activation upon cardiac structure and function, transgenic mice were created that express constitutively activated rac1 specifically in the myocardium. Transgenic rac1 protein was expressed at levels comparable to endogenous rac levels, with activation of the rac1 signaling pathway resulting in two distinct cardiomyopathic phenotypes: a lethal dilated phenotype associated with neonatal activation of the transgene and a transient cardiac hypertrophy seen among juvenile mice that resolved with age. Neither phenotype showed myofibril disarray and hypertrophic hearts were hypercontractilein working heart analyses. The rac1 target p21-activated kinase translocated from a cytosolic to a cytoskeletal distribution, suggesting that rac1 activation was inducing focal adhesion reorganization. Corroborating results showed altered localizations of src in dilated cardiomyopathy and paxillin in both cardiomyopathic phenotypes. This study, the first examination of rac1-mediated cardiac effects in vivo, demonstrates that dilation and hypertrophy can share a common molecular origin and presents evidence that both timing and concurrent signaling from multiple pathways can influence cardiac remodeling.

Animals↗
PubMed2000

Assaults on staff by psychiatric patients in community residences.

The study examined assaultive behavior directed toward staff of community-based residential facilities by patients who had been discharged to these facilities from Massachusetts state psychiatric hospitals in the early 1990s. Observed rates of assault declined by 61 percent over a six-and-a-half-year period. Early in the study period, male patients were more likely than female patients to be assaultive, but men and women had similar rates of assaultiveness later in the study period, after they had been in residential placements for several years. The most common diagnosis among assaultive patients was schizophrenia.

Adult↗
PubMed2000

Effectiveness of a clinical pathway for inpatient asthma management.

BACKGROUND: Clinical pathways for asthma are tools that have the potential to improve compliance with nationally recognized management guidelines, but their effect on patient outcomes has not been documented. OBJECTIVES: To determine the effect of an asthma clinical pathway on patients' length of stay, use of nebulized beta-agonist therapy while hospitalized, and use of acute care clinics for 2 weeks after discharge. DESIGN/METHODS: The study was a randomized, controlled trial. Patients between the ages of 2 and 18 years admitted with an asthma exacerbation and not under the care of an asthma specialist were eligible for the study. Patients were randomized either to a conventional ward (control group) or to a ward using the clinical pathway (intervention group). For 2 weeks after discharge, we collected data to determine whether patients visited a health care provider for worsening asthma. RESULTS: One hundred ten patients (26%) were enrolled. Control and intervention groups had similar demographic and asthma severity profiles. The intervention group had an average length of stay 13 hours shorter than did the control group. In addition, at every dosing interval, the intervention group received less nebulized beta-agonist therapy. There were no deaths in either group. CONCLUSION: A clinical pathway for inpatient asthma decreased the length of stay and beta-agonist medication use with no adverse outcomes or increased acute-care encounters through 2 weeks after discharge.

Administration, Inhalation↗
PubMed2000

How do patients perceive support from nurses?

Patients found support in the clinical friendship of nurses. The nurses instilled a sense of normality into their activities, creating a supportive atmosphere. Patients expressed a need for reciprocity in their relationship with the nurses. This relationship should be balanced and sustainable.

Adult↗
PubMed2000

Anticholinesterases in the treatment of Alzheimer's dementia--the first year's experience in Argyll & Clyde.

The local experience of the introduction of a new anticholinesterase treatment for Alzheimer's dementia is described, including the use of a protocol to introduce the use of these drugs. The results in the first 233 patients seen are reported. The protocol seemed to anticipate SMAC. guidelines and to be easy to operate; the drug appeared to have clear clinical effect.

Activities of Daily Living↗
PubMed1999

South Turkwel: a new pliocene hominid site in Kenya.

New fossils discovered south of the Turkwel River in northern Kenya include an associated metacarpal, capitate, hamate, lunate, pedal phalanx, mandibular fragment, and teeth. These fossils probably date to around 3.5 m.y.a. Faunal information suggests that the environment at South Turkwel was predominantly bushland. The mandibular and dental remains are fragmentary, but the postcranial fossils are informative. Comparisons with Australopithecus, modern human, chimpanzee and gorilla hand bones suggest that the Turkwel hominid was most like Australopithecus afarensis and A. africanus. Carpometacarpal articulations are intermediate between those of modern humans and African apes, suggesting enhanced gripping capabilities compared with extant apes. The hamulus was strikingly large, similar in proportion only to Neandertals and some gorillas, suggesting the presence of powerful forearms and hands. There are no indicators of adaptations to knuckle-walking or suspensory locomotion in the hand, and the pedal phalanx suggests that this hominid was habitually bipedal.

Animals↗
PubMed1999

Ageing in Europe--challenges and consequences.

This article outlines the five key social and economic policy challenges presented by the ageing population of the European Union (EU). These challenges are the maintenance of economic security in old age, preserving intergenerational solidarity, combating the social exclusion created by age discrimination, providing long-term care in the context of changes in family and residence patterns, and enabling older people to participate in society as full citizens. The nature of each of these challenges is discussed and priorities pinpointed. The discussion of policy challenges is preceded by an outline of the demographic context of the EU: the combination of declining fertility and increasing longevity. This also includes a discussion of the links between demography and policy. The conclusion of the article considers the current threat to the European model of social policy and suggests ways in which the gerontological community might contribute to its defence.

Aged↗
PubMed1999

Intra-abdominal bleeding caused by spontaneous rupture of an accessory spleen: the CT findings.

Accessory spleens are common. Their clinical importance lies in the need to include their removal when performing a splenectomy for primary haematological disorders, or as the source of 'preservable' splenic tissue in cases of ruptured primary spleen. Rupture of a normal spleen almost always occurs because of trauma, spontaneous rupture is rare. In pathological spleens, however, 'spontaneous' rupture is more widely reported, although it is argued that minor trauma is often still responsible in these cases. We report a case of spontaneous isolated rupture of a histologically normal accessory spleen and show the CT findings.

Female↗