New graduates in the UK presently spend one year in training as Vocational Dental Practitioners (VDPs) in preparation for primary dental care. There is a growing recognition that the emerging ...workforce has very different professional expectations to those of earlier generations, with implications for the profession, patients and the performance of health systems. The objectives of this study were to investigate why VDPs' in England and Wales perceive they chose dentistry as a professional career; how they perceive their vision has changed and the implications for their professional career plans, both short- and longterm.
Purposive sampling of schemes was undertaken to include urban, rural and metropolitan schemes, schemes in areas with and without dental schools and geographic coverage across England and Wales. All VDPs in these schemes were initiated to participate in this qualitative study using focus groups. A topic guide was utilised to standardise data collection. Informants' views were recorded on tape and in field notes. Data were transcribed and analysed using Framework Methodology.
A total of 99 VDPs participated in the 10 focus groups. Their choice of dentistry as a professional career was motivated by multiple categories of influence: 'academic', 'healthcare', 'lifestyle', the influence of 'family', 'friends', 'careers advice' and 'work experience'. Consideration of the features of the 'professional job' appears to have been key to their choice of dentistry and the 'active rejection of medicine' as an alternative career.Entry into the profession was proving a challenging process for some but not all VDPs. Informants perceived that their vision had been moderated as a result of 'personal student debt', 'national workforce initiatives', 'limitations on clinical practice' and the 'cost of additional training'.Short term goals focused around 'recovery from the past' and 'preparation for the future'. Longterm goals covered the spectrum of opportunities within dentistry. Factors influencing VDPs longterm career plans fell into six main categories: professional, personal, financial, political, social and cultural.
VDPs chose dentistry because they perceived that it provides a financially lucrative, contained career in healthcare, with professional status, job security and the opportunity to work flexibly. They perceive that their vision is challenged by changes affecting education and the healthcare system. Longterm professional expectations were closely linked with their personal lives and support a vision of a favourable work/life balance.
Phosphatidylinositol 5-phosphate (PtdIns5P) is a relatively recently discovered inositol lipid whose metabolism and functions are not yet clearly understood. We have transfected cells with a number ...of enzymes that are potentially implicated in the synthesis or metabolism of PtdIns5P, or subjected cells to a variety of stimuli, and then measured cellular PtdIns5P levels by a specific mass assay. Stable or transient overexpression of Type IIα PtdInsP kinase, or transient overexpression of Type Iα or IIβ PtdInsP kinases caused no significant change in cellular PtdIns5P levels. Similarly, subjecting cells to oxidative stress or EGF stimulation had no significant effect on PtdIns5P, but stimulation of HeLa cells with a phosphoinositide-specific PLC-coupled agonist, histamine, caused a 40% decrease within 1
min. Our data question the degree to which inositide kinases regulate PtdIns5P levels in cells, and we discuss the possibility that a significant part of both the synthesis and removal of this lipid may be regulated by phosphatases and possibly phospholipases.
Noninvasive measurement of absolute coronary arterial flow and coronary flow reserve would be of considerable use in the diagnosis and management of patients with coronary artery disease. ...Phase-contrast magnetic resonance imaging (MRI) has been used to measure flow in a variety of vessels. The goal of the present study was to determine if MRI measurements of coronary artery flow in a single breath-hold can be used to determine flow reserve and the severity of pericardial stenosis.
In eight mongrel dogs, a closed chest model of partial left anterior descending coronary artery (LAD) occlusion was created. Coronary flows in the left circumflex artery (LCx) and LAD were measured at rest and during adenosine infusion using velocity-encoded, breath-hold MRI and perivascular ultrasound (US) flowmeters. MRI measurements of absolute coronary flow and coronary flow reserve were highly correlated with US (r = .96 and .94, respectively). Flow reserve measured in the constricted LAD was significantly lower than that in the unconstricted LCx by both US (P = .002) and MRI (P = .011).
MRI measurements of coronary flow and flow reserve were in good agreement with US measurements. In addition, MRI measurements of coronary flow reserve successfully discriminated stenotic from normal vessels. These results indicate that MRI is a useful method for the noninvasive assessment of coronary flow and stenosis.
Between 10% and 35% of women with operable breast cancer will experience an isolated locoregional recurrence following their primary treatment. There is currently no good evidence that adjuvant ...systemic treatment is effective in this situation and there is no standard treatment for women who have such a recurrence.
To investigate whether additional systemic treatment will improve the result of local therapy in regard to relapse-free and overall survival in women with potentially curatively resected loco-regional recurrence following breast cancer, who have not had a previous or synchronous distant metastases.
Searches were done, in the first half of 2001, of the specialised register of the Cochrane Breast Cancer Collaborative Review Group, The Cochrane Library, MEDLINE and EMBASE. In addition, the records of the Early Breast Cancer Trialists' Collaborative Group were checked for any relevant trials. The citations in articles reviewing the treatment of locoregional recurrence of breast cancer were checked.
Randomised controlled trials or trials in which women were allocated to treatment or observation by a quasi-random process (such as alternation or date of birth) were eligible. Our aim was to consider separately women with a first incidence of isolated loco-regional recurrence in the treated breast, the chest wall or the regional lymphnode areas (except clavicular nodes) which can be resected without (R0) or with (R1) microscopically demonstrable residual disease. Women with previous or synchronous distant metastases were to be excluded from this part of the review. The second part of the review was to consider women with inoperable loco-regional recurrence and / or clavicular lymphnode involvement, regardless of previous or synchronous metastases.
We identified three closed studies in which there were a total of four randomised comparisons of systemic therapy versus observation for women who have received radiotherapy for loco-regional recurrence of breast cancer. One trial assessed Actinomyicin-D and randomised 32 patients in the 1960s and another randomised the same number of women to alpha-interferon versus observation in the early 1980s. The Swiss SAKK trial assessed tamoxifen for "good risk" patients and combination chemotherapy (Vincristine, Doxorubicin and Cyclophosphamide) for "poor risk" patients. It randomised 178 and 50 women respectively during 1982-1991. Where possible, data on relapse-free and overall survival were extracted for these trials and analysed using RevMan 4.1. No attempt was made to pool the results of the studies because of clinical heterogeneity and the small number of randomised patients. Three ongoing trials of chemotherapy versus observation have been identified.
The trial of 32 women who received either radiotherapy alone or in combination with systemic administration of Actinomycin-D found that chemotherapy improved the local control rate but had no apparent effect on overall survival. The interferon trial, which also included a total of only 32 patients, showed that the addition of alpha-Interferon to local treatment of locoregional recurrent breast cancer had no apparent effect on the further course of the disease. The Swiss SAKK trial of tamoxifen (178 women randomized) found an improvement in disease-free survival but not in overall survival and no results are available for the 50 women randomized into the concurrent trial of chemotherapy. The three ongoing trials of chemotherapy have a total target accrual of nearly 2000 patients.
This systematic review of randomised trials provides insufficient evidence to do other than conclude that the most appropriate form of practice for women with loco-regional recurrence of breast cancer is participation in randomised trials of systemic treatment versus observation.
Polarimetric data associated with multi-parameter observational campaigns of selected bright O-type stars and their variable winds, are analysed in relation to the outcomes of the UV and optical ...spectroscopic studies. For the stars $\xi\,$Per and $\lambda\,$Cep, individual measurement uncertainties are $\Delta p\sim\pm0.0002$ with nightly mean uncertainties of $\Delta p\sim\pm0.00007$. Although variability is apparent on a night-to-night basis, with differences in $\delta p \sim 0.0002$, no correlations are found between these and the periodic behaviours associated with the stellar Si IV and Hα lines. Similar polarimetric variability is seen in the data for the standard star $\phi\,$Cas used as a reference in this observing campaign. It is suggested that all of these low level fluctuations are not intrinsic to the stars but are engendered by structured instrumental polarization in the diffraction pattern and depolarization effects in combination with inconsistent target acquisition and with variable seeing conditions in the Earth's atmosphere. Reassessment of older data for $\lambda\,$Cep from Hayes (CITE) also supports this thesis.
As part of a gene tagging strategy to study the developmental regulation of patterns of plant gene expression, a promoterless uidA (gusA) gene, encoding the beta-glucuronidase (GUS) reporter, was ...introduced into populations of tobacco, Arabidopsis and potato by Agrobacterium-mediated gene transfer. The objective was to generate random functional fusions following integration of the gusA gene downstream of native gene promoters. We describe here a detailed analysis of levels and patterns of gusA activation in diverse organs and cell types in those populations. gusA activation occurred at high frequency in all three species, and unique patterns of fusion gene expression were found in each transgenic line. The frequency of gusA activation was differentially biased in different organs in the three species. Fusion gene activity was identified in a wide range of cell types in all organs studied, and expression patterns were stably transmissible to the T2 and T3 progeny. Developmentally-regulated and environmentally-inducible expression of gusA is described for one transgenic line. Phenotypic variants were detected in the transgenic population. These results demonstrate the potential of T-DNA insertion as a means of creating functional tags of genes expressed in a wide spectrum of cell types, and the value of the approach as a complement to standard T-DNA insertional mutagenesis and transposon tagging for developmental studies is discussed.
Lactate dynamics in the brain, cerebrospinal fluid (CSF), and serum were studied in 20 chloralose-anesthetized cats following fluid-percussion trauma. Brain lactate and brain tissue pH were measured ...by hydrogen-1 and phophorus-31 magnetic resonance spectroscopy. The CSF, arterial, and cerebrovenous serum lactate levels as well as serum glucose concentration were quantified. In the six sham-operated control animals, brain, CSF, cerebrovenous, and arterial lactate levels as well as brain pH remained at normal values. In the five animals in the mild-trauma group (1.6 atm), brain and CSF lactate levels were moderately elevated, although the brain pH and serum lactate content remained at control values. Severe trauma (3.1 atm) in nine cats produced an 82% increase in the brain lactate index and a reduction in brain tissue pH (7.02 +/- 0.02 to 6.95 +/- 0.02; mean +/- standard error of the mean), indicating brain tissue acidosis caused by excessive lactate accumulation. Brain lactate levels reached a peak 1 1/2 hours after severe trauma, then steadily decreased to normal levels by 8 hours posttrauma. Maximum increases of CSF and arterial lactate levels (from 1.4 +/- 0.2 to 4.1 +/- 0.4 and from 1.6 +/- 0.2 to 4.1 to 0.6 mmol/liter, respectively) were observed 15 minutes after trauma, and the values decreased during the next 2 hours. The response was biphasic, with a secondary rise observed in both CSF and serum lactate levels during the remaining 4 hours of the experiment. The difference between the arterial and venous lactate levels (A-Vlact) gradually increased and reached a peak 2 hours postinjury (from -0.05 +/- 0.10 to -0.41 +/- 0.09 mmol/liter). The results of this study show that the production of lactate in brain tissue, CSF, and blood increased in proportion to the severity of the injury. The observation that lactate levels in blood and CSF are maximum immediately following impact while brain lactate and A-Vlact are gradually increasing suggests that the brain-tissue production of lactate fails to account for the rapid appearance of lactate in CSF and blood. It is speculated that the initial elevation of CSF lactate values reflects the systemic response of trauma, and the secondary rise of CSF lactate levels following severe trauma is due to slow seepage of lactate produced by brain tissue into the CSF space. These studies are the first to describe the temporal profile of brain lactate production and eventual clearance by CSF and blood in fluid-percussion injury.
The study examined the importance of embryonic donor age for the survival of nigral grafts in 6-OHDA-lesioned marmosets. The issue as to whether donor age is critical for the survival of nigral ...grafts in primates is controversial, because several early reports suggested that relatively old tissue could survive transplantation and produce functional benefits in monkeys, in contrast to the restrictive time dependence observed in rodents. Embryonic marmoset donors embryos of three different ages were employed: 1) E74 (Carnegie stage 18-19); 2) E83-84 (Carnegie stage 23+); 3) E92-93 (foetal period). The nigral neurons derived from the ventral mesencephalon in the two older donor age groups did not survive well when grafted to the striatum of adult marmosets with unilateral 6-OHDA lesions. Although a few tyrosine hydroxylase (TH+) neurons could be identified by immunohistochemistry at graft sites in all recipients in older donor age groups, the numbers of surviving neurons in these were small, on average typically less than 100 TH+ cells. These small grafts were not sufficient to affect amphetamine-induced rotation. In contrast, many more TH+ cells typically survived transplantation in the recipients of graft tissue derived from the youngest donors and amphetamine-induced rotation was significantly reduced in this group alone. The time course and extent of the reduction in rotation was remarkably similar to that observed in previous marmoset nigral graft studies, confirming the utility of amphetamine-induced rotation as a sensitive and reliable indicator of nigral graft function in this species. Considering these results and other recent evidence from monkey to monkey, human to rat, and human to human graft studies, the survival of embryonic nigral tissues derived from primate donors transplanted into the striatum does appear to be critically dependent on the age of the donor tissue.
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