Search PubMed⌕ Search

Biomedical subjects

R Wilson

Publications and source records attributed to R Wilson.

At least 109 records · Page 6Linked to original sources

If the NHS introduced a '50 procedures a year' policy, what proportion of consultant firms would be affected?

BACKGROUND: Governments, insurers, quality assurance agencies and others have used the higher volume = better quality relationship as a basis for health policy. This relationship is probably real enough to justify these policies. However, even if it were not real, there are other reasons why these and other organizations such as the National Health Service (NHS) may favour high-volume providers. This paper attempts to answer the question: 'If, for common elective procedures, the NHS instituted a high-volume purchasing policy that requires consultant firms to perform a minimum of "50 procedures a year", what proportion of consultant firms would be affected?' The aims of this study were to estimate the proportion of NHS consultant firms that perform common elective procedures less than 50 times a year and to estimate the proportion of firms that would have to stop providing these procedures if a '50 procedures a year' purchasing policy were introduced. METHOD: A descriptive analysis was carried out and modelling was performed on data stored in an NHS health episode statistics database of patients treated in West Midlands NHS facilities. For each of 12 common elective procedures we assumed that a volume threshold of at least 50 a year were set, and calculated the proportion of NHS consultant firms undertaking each procedure who performed less than 50 of those procedures each year and the proportion of firms who would have had to stop providing each procedure. RESULTS: All firms performing some procedures, e.g. cataract extraction, did so at least 50 times a year. By contrast, no firm repaired more than 50 recurrent inguinal hernias a year. If a volume threshold of at least 50 procedures a year were set for a basket of 12 common elective procedures, then about 40 per cent of firms would no longer be eligible to provide a procedure. Even if a lower 'one a month' threshold were set, about 20 per cent of firms would still not be eligible to provide that procedure. CONCLUSION: Introduction of a high-volume policy would affect a considerable number of firms, as many NHS consultant firms perform some common elective procedures infrequently. Some consultants would see the introduction of a high-volume policy as an opportunity to further specialize and super-specialize. Others would see it as a policy that restricts them to providing a narrower range of procedures, makes their professional practice less interesting, and reduces their professional autonomy. Postgraduate training institutions need to consider the possibility and implications of high-volume policies, as many junior doctors would probably need to learn to provide a narrower range of skills than at present.

Elective Surgical Procedures↗

A novel automated injection system for angiography.

The present method of performing manual coronary angiography requires repetitive manipulation of a cumbersome stopcock-manifold system and contrast injection by hand syringe. This study reports a novel mechanical contrast injector with automated manifold that provides finger touch operator-controlled contrast injections. The ACIST Injection System components include a software-controlled syringe injector, a disposable automated manifold without stopcocks, a disposable hand controller, and a touch screen control panel. The ACIST system was evaluated in 50 patients undergoing diagnostic coronary angiography (n = 37) or coronary interventions (n = 13). In all cases, the system was easy to use and provided excellent quality images even with four catheters, as well as imaging during stent positioning with 6Fr guides. This mechanical injector facilitates precision operator-controlled angiographic injections, provides superb high quality coronary images even with very small lumen catheters, and expedites ventriculography during angiographic procedures.

Automation↗

Managed care: a view from Europe.

This article summarizes recent developments in the United Kingdom, the Netherlands, Switzerland, and the new Baltic states that reflect the influence of US managed care concepts and practices. We emphasize (a) developments in restructuring traditional health insurance mechanisms by shifting premium and out-of-pocket burdens to consumers so as to constrain demand and costs and (b) reliance on prospective hospital budgets and case management by primary physicians. Social insurance mechanisms and universal coverage remain national tasks as well as basic components of the social structure of most European countries. Full open-market competition between traditional sick funds and private insurance companies and the introduction of for-profit MCOs beholden to their shareholders appears unlikely on other than an experimental basis. Increased competition between providers may well result from the new right of insurers and payers to contract with medical care providers of their choice. It remains to be shown how far these experiments, which differ substantially between the countries examined, will succeed in their objectives and become permanent features of their national systems.

Cost Control↗

Efficacy of gemifloxacin in acute exacerbations of chronic bronchitis: a randomised, double-blind comparison with trovafloxacin.

This randomised, double-blind, double-dummy, multinational study compared the efficacy and safety of gemifloxacin with trovafloxacin in the treatment of acute exacerbations of chronic bronchitis. There were 617 patients randomised: 303 to gemifloxacin and 314 to trovafloxacin. Clinical success rates at follow-up (clinical per-protocol population) were 91.5% for gemifloxacin and 87.6% for trovafloxacin. For the intent-to-treat population, the clinical efficacy of gemifloxacin was statistically significantly superior to that of trovafloxacin. In general, the in vitro activity of gemifloxacin against the major respiratory bacterial pathogens was superior to that of other antibiotics tested. Per-patient bacteriological success rates at follow-up (bacteriology per-protocol population) were 86.8% for gemifloxacin and 82.4% for trovafloxacin. Both agents were well tolerated. The clinical and bacteriological efficacy of a once-daily 5-day course of gemifloxacin is at least as good as that of a similar regimen of trovafloxacin in the treatment of acute exacerbations of chronic bronchitis.

Adult↗

Vitamin E attenuates the injurious effects of bioactive phospholipids on human ciliated epithelium in vitro.

Bioactive phospholipids (PL), particularly lysophosphatidylcholine (LPC), are being increasingly implicated in the pathogenesis of various acute and chronic inflammatory disorders, particularly those of the airways, while there is emerging evidence that vitamin E may function as a natural antagonist of these lipid mediators of inflammation. The aims of this study were to document the effects of vitamin E on the inhibition of ciliary beating and damage to structural integrity of human ciliated epithelium induced by the PL, platelet-activating factor (PAF), lyso-PAF and LPC in vitro in relation to the anti-oxidative and membrane-stabilizing properties of the vitamin. Ciliary beat frequency was measured by a phototransistor technique, and damage to structural integrity assessed by a visual-scoring index, while superoxide production by polymorphonuclear leukocytes and membrane-stabilizing potential were measured using lucigenin-enhanced chemiluminescence and haemolytic procedures, respectively. All three PL caused inhibition of ciliary beating and structural damage to human ciliated epithelium by membrane-directed cytotoxic mechanisms, which were potentiated by human polymorphonuclear leukocytes due to induction of oxidant-mediated injury. Both direct and phagocyte-inflicted epithelial injury was attenuated by vitamin E. In haemolytic and chemiluminescence assays, vitamin E neutralized both the membrane-destabilizing and pro-oxidative actions of all three PL, while spectrophotometric analysis of mixtures of vitamin E with PAF, lyso-PAF and LPC revealed alterations in peak intensity, as well as peak shifts, indicative of physicochemical interactions between the vitamin and the PL. Vitamin E status may be a determinant of susceptibility to phospholipid-mediated airway inflammation and damage.

Cells, Cultured↗

Primary ciliary dyskinesia syndrome associated with abnormal ciliary orientation in infants.

Primary ciliary dyskinesia (PCD) syndrome associated with abnormal ciliary orientation but with normal ciliary ultrastructure has been described in adults, but there are no normal ranges for orientation in infants, despite the fact that half of all patients with PCD present in the new-born period. Nasal brush biopsies were obtained from eight infants (three males), mean age 13.1 months, range 7-23, in order to determine ciliary orientation. They had no upper or lower airway disease and normal organ arrangement and were undergoing general anaesthesia for other reasons. Two infants with typical PCD syndrome but normal ultrastructure of individual cilia also had orientation studies. In the eight normal subjects, a mean of 254 central pairs was examined, range 82-453. The mean ciliary orientation was 14.9 degrees, range 12.9-17.5. The two infants with PCD syndrome but normal ultrastructure of individual cilia had ciliary orientation of (Case 1) 44.5 degrees (range 10.6-64.5) in 218 central pairs; and on a second occasion, 28.9 degrees, (range 9.0-47.5) in 259 central pairs; for Case 2, 24.4 degrees, (range 13.1-38.4) in 196 central pairs. The normal range for ciliary orientation is similar in infants to that described in other work in adults. The two cases of phenotypic primary ciliary dyskinesia in the presence of normal ciliary ultrastructure but abnormal ciliary orientation in infants supports the contention that measurement of ciliary orientation should be part of the assessment of ciliary structure and function in cases of possible primary ciliary dyskinesia, in particular when the ultrastructure of individual cilia appear to be normal.

Cilia↗

Bacteria, antibiotics and COPD.

Bacterial infection is one of several important causes of exacerbations of chronic obstructive pulmonary disease (COPD) that may coexist. COPD is a heterogeneous condition and the incidence of bacterial infection is not uniform; mucus hypersecretion may be an important risk factor. The bacteriology of infections varies depending on the severity of the underlying airway disease. There is now a much better understanding of the pathogenesis of bacterial infections of the respiratory mucosa. Lower airway bacterial colonization may be a stimulus for chronic inflammation and may influence the interval between exacerbations. Antibiotic resistance has increased in all the major pathogens. Antibiotics are an important part of the treatment of acute exacerbations of COPD and the decision about whether to give an antibiotic can be made on clinical grounds. It is more difficult to decide, on the available evidence, whether patient characteristics and the risk of antibiotic resistance should influence choice of empiric antibiotic treatment. Most new antibiotics are modifications of existing structures, suggesting that every effort should be made to conserve the sensitivity of current antibiotics by using them appropriately.

Drug Resistance↗

Age distribution of cancer in mice: the incidence turnover at old age.

We have studied cancer incidence in mice as a function of age in those cohorts where the rodents are allowed to live very close to their full natural lifetime. We find that the incidence rises as a function of age, but then flattens and turns over at an age of about 800 days. This behaviour is similar to that which we observed (Pompei and Wilson, 2001) in the Surveillance, Epidemiology, and End Results (SEER) data where the age distribution of human cancer incidence turns over at about age 80. Although other fits are possible, the three-parameter beta function model fits both the mouse data and the human data well. The beta model implies, and the data do not deny, the interpretation that cancer is not a certainty and mice may also outlive their cancers, although high-dose cohort results suggest cancer might be certain if dose is sufficiently high. Limited data suggest that the cancer age distribution, including the turnover, may be time shifted by dietary restriction.

Age Distribution↗

Opioids for chronic nonmalignant pain. Attitudes and practices of primary care physicians in the UCSF/Stanford Collaborative Research Network. University of California, San Francisco.

BACKGROUND: We hoped to determine the attitudes and practices of primary care physicians regarding the use of opioids to treat chronic nonmalignant pain (CNMP). We also examined the factors associated with the willingness to prescribe opioids for CNMP. METHODS: A survey was mailed to primary care physicians in the University of California, San Francisco/Stanford Collaborative Research Network. This survey contained questions regarding treatment in response to 3 case vignettes, the use of opioids for CNMP in general, and the demographic characteristics of the physicians. RESULTS: Among 230 physicians surveyed, 161 (70%) responded. Two percent of the respondents were never willing to prescribe schedule III opioids (eg, acetaminophen with codeine) as needed for patients with CNMP that persisted unchanged after exhaustive evaluation and attempts at treatment. Thirty-five percent were never willing to prescribe schedule II opioids (eg, sustained-release morphine) on an around-the-clock schedule for these patients. The most significant predictor of willingness to prescribe opioids for patients with CNMP was a lower level of concern about physical dependence, tolerance, and addiction. CONCLUSIONS: Primary care physicians are willing to prescribe schedule III opioids as needed, but many are unwilling to use schedule II opioids around the clock for CNMP. Individual prescribing practices vary widely among primary care physicians. Concerns about physical dependence, tolerance, and addiction are barriers to the prescription of opioids by primary care physicians for patients with CNMP.

Adolescent↗

Measurements of the mass, total width, and two-photon partial width of the eta(c) meson.

Using 13.4 fb(-1) of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudoscalar charmonium in the decay eta(c)-->K(0)(S)K-/+pi(+/-). We have measured the eta(c) mass to be [2980.4+/-2.3 (stat)+/-0.6 (syst)] MeV and its full width as [27.0+/-5.8 (stat)+/-1.4 (syst)] MeV. We have determined the two-photon partial width of the eta(c) meson to be [7.6+/-0.8 (stat)+/-0.4 (syst)+/-2.3 (br)] keV, with the last uncertainty associated with the decay branching fraction.

Journal Article↗

Ceramide-coated balloon catheters limit neointimal hyperplasia after stretch injury in carotid arteries.

Neointimal hyperplasia at the site of surgical intervention is a common and deleterious complication of surgery for cardiovascular diseases. We hypothesized that direct delivery of a cell-permeable growth-arresting lipid via the balloon tip of an embolectomy catheter would limit neointimal hyperplasia after stretch injury. We have previously demonstrated that sphingolipid-derived ceramide arrested the growth of smooth muscle cell pericytes in vitro. Here, we show that ceramide-coated balloon catheters significantly reduced neointimal hyperplasia induced by balloon angioplasty in rabbit carotid arteries in vivo. This ceramide treatment decreased the number of vascular smooth muscle cells entering the cell cycle without inducing apoptosis. In situ autoradiographic studies demonstrated that inflating the balloon catheter forced cell-permeable ceramide into the intimal and medial layers of the artery. Intercalation of ceramide into vascular smooth muscle cells correlated with rapid inhibition of trauma-associated phosphorylation of extracellular signal-regulated kinase and protein kinase B. These studies demonstrate the utility of cell-permeable ceramide as a novel therapy for reducing neointimal hyperplasia after balloon angioplasty.

Angioplasty, Balloon, Coronary↗

Fibroblast growth factor receptor-dependent morphogenesis of the Drosophila mesoderm.

The Drosophila fibroblast growth factor (FGF) receptors Heartless and Breathless are required for the morphogenesis of the mesoderm and the tracheal system. In this article we discuss a number of questions relating to the morphogenesis of these tissues and speculate on poorly understood aspects of the underlying mechanisms. As yet a ligand has not been identified for Heartless, but in the case of Breathless the ligand may in some situations act as a chemotactic signal. We consider it unlikely that release of a distant chemotactic signal plays a role in the morphogenesis of the mesoderm. Instead we propose that the change in the mesoderm from an invaginated epithelium to a single layer of cells spread out on the ectoderm could be a result of the mesodermal cells trying to maximize their contact with the ectoderm. Exactly how the activation of the FGF receptors affects cell behaviour and leads to cell movement is not understood. The signal could simply be permissive, causing cells to become motile, or it could act as a directional signal for cells that are already motile, or perhaps provide both functions. Furthermore, it is unclear how signal transduction is coupled to morphological change. It seems unlikely that activation of transcription targets is essential for cell migration and it is possible that FGF signalling may have a direct effect on the cytoskeleton independent of the activation of the mitogen-activated protein kinase cascade. Analysis of the function of dof, which encodes a cytoplasmic protein required for FGF signal transduction may provide an insight into these issues.

Animals↗