BLOOD CONSERVATION IN PATIENTS UNDERGOING ELECTIVE PRIMARY TOTAL HIP JOINT ARTHROPLASTY: AN ECONOMIC EVALUATION

Objectives: The purpose of this research is to assess the long-term cost-effectiveness of blood conservation by incorporating both ‘known’ and ‘unknown’ blood-borne agents into an economic evaluation of blood conservation. Methods: A Markov cohort simulation is used to generate estimates of the costs and effects of blood conservation. These estimates are then compared to the costs and effects of usual care, using the incremental cost-effectiveness ratio (ICER). The resulting ratio gives an estimate of the cost and effect tradeoff of implementing such a program. Cost-effectiveness is discussed in terms of the decision makers’ willingness to pay for blood safety measures. Results: ICERs incorporating ‘unknown’ risks are substantially lower than those that only incorporate ‘known’ risks such as HIV, HCV, and HBV. Conclusions: Based on these results it would appear that ‘unknown’ risks have the potential to impact, in a measurable way, the cost-effectiveness of blood conservation

Magnetization of undoped 2-leg S = 1/2 spin ladders in La4Sr10Cu24O41

Magnetization data of single crystalline La4Sr10Cu24O41 are presented. In this compound, doped spin chains and undoped spin ladders are realized. The magnetization, at low temperatures, is governed by the chain subsystem with a finite interchain coupling which leads to short range antiferromagnetic spin correlations. At higher temperatures, the response of the chains can be estimated in terms of a Curie-Weiss law. For the ladders, we apply the low-temperature approximation for a S=1/2 2-leg spin ladder by Troyer et al.Comment: 2 pages, 2 figure

Dietary fibre and phytate; a balancing act. Results from 3 time points in a British Birth Cohort

An investigation was carried out to determine whether there were significant changes in the intake of dietary fibre (non-starch polysaccharide; NSP) and phytate of adult men and women in the UK from 1982 (aged 36 years) to 1999 (aged 53 years). The 1253 subjects studied were members of the Medical Research Council National Survey of Health and Development; a longitudinal study of a nationally representative cohort of births in 1946. Food intake was recorded in a 5-day diary at age 36 years in 1982, 43 years in 1989 and 53 years in 1999. The food composition database was amended with revised values for phytate. Outcome measures were mean intakes of total NSP and phytate by year, gender and food source. There were significant changes in total NSP and phytate intake over the 3 time-points. Intakes of NSP rose significantly between 1982 and 1999 for men and women but phytate intakes rose significantly only between 1989 and 1999. Cereal foods were the most important source of both NSP and phytate. Between 1989 and 1999 there was a significant increase in the contribution from pasta, rice and other grains. This study shows that an increase in dietary fibre that is in accordance with dietary guidelines would almost inevitably be accompanied by a rise in phytate. The increased dietary phytate is discussed in relation to its recognised inhibition of mineral absorption and its merits with regard to protection against some cancers and other diseases of an ageing population

Factors associated with polypharmacy and excessive polypharmacy in older people with Intellectual Disability differ from the general population; a cross-sectional observational nationwide study

Objectives: (1) To evaluate the prevalence of polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines) and (2) to determine associated demographic and clinical characteristics in an ageing population with intellectual disabilities (IDs). Design: Observational cross-sectional study. Setting: Wave One (2009/2010) of the Intellectual Disability Supplement to the Irish Longitudinal Study on Ageing (IDS-TILDA). Participants: A nationally representative sample of 753 persons with ID, aged between 41 and 90 years. Participants/proxy reported medicines ( prescription and over the counter) taken on a regular basis; medication data was available for 736 participants (98%). Main outcome measures/interventions: Participants were divided into those with no polypharmacy (0–4 medicines), polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines). Medication use patterns were analysed according to demographic variables and reported chronic conditions. A multinomial logistic regression model identified factors associated with polypharmacy (5–9 medicines) and excessive polypharmacy (≥10 medicines). Results: Overall, 90% of participants reported use of medicines. Polypharmacy was observed in 31.5% of participants and excessive polypharmacy in 20.1%. Living in a residential institution, and reporting a mental health or neurological condition were strongly associated with polypharmacy and excessive polypharmacy after adjusting for confounders, but age or gender had no significant effect. Conclusions: Polypharmacy was commonplace for older adults with ID and may be partly explained by the high prevalence of multimorbidity reported. Review of appropriateness of medication use is essential, as polypharmacy places ageing people with ID at risk of adverse effects

Use of cumulative incidence of novel influenza A/H1N1 in foreign travelers to estimate lower bounds on cumulative incidence in Mexico

Background: An accurate estimate of the total number of cases and severity of illness of an emerging infectious disease is required both to define the burden of the epidemic and to determine the severity of disease. When a novel pathogen first appears, affected individuals with severe symptoms are more likely to be diagnosed. Accordingly, the total number of cases will be underestimated and disease severity overestimated. This problem is manifest in the current epidemic of novel influenza A/H1N1. Methods and Results: We used a simple approach to leverage measures of incident influenza A/H1N1 among a relatively small and well observed group of US, UK, Spanish and Canadian travelers who had visited Mexico to estimate the incidence among a much larger and less well surveyed population of Mexican residents. We estimate that a minimum of 113,000 to 375,000 cases of novel influenza A/H1N1 have occurred in Mexicans during the month of April, 2009. Such an estimate serves as a lower bound because it does not account for underreporting of cases in travelers or for nonrandom mixing between Mexican residents and visitors, which together could increase the estimates by more than an order of magnitude. Conclusions: We find that the number of cases in Mexican residents may exceed the number of confirmed cases by two to three orders of magnitude. While the extent of disease spread is greater than previously appreciated, our estimate suggests that severe disease is uncommon since the total number of cases is likely to be much larger than those of confirmed cases

Factors associated with polypharmacy and excessive polypharmacy in older people with Intellectual Disability differ from the general population; a cross-sectional observational nationwide study

Objectives: (1) To evaluate the prevalence of polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines) and (2) to determine associated demographic and clinical characteristics in an ageing population with intellectual disabilities (IDs). Design: Observational cross-sectional study. Setting: Wave One (2009/2010) of the Intellectual Disability Supplement to the Irish Longitudinal Study on Ageing (IDS-TILDA). Participants: A nationally representative sample of 753 persons with ID, aged between 41 and 90 years. Participants/proxy reported medicines ( prescription and over the counter) taken on a regular basis; medication data was available for 736 participants (98%). Main outcome measures/interventions: Participants were divided into those with no polypharmacy (0–4 medicines), polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines). Medication use patterns were analysed according to demographic variables and reported chronic conditions. A multinomial logistic regression model identified factors associated with polypharmacy (5–9 medicines) and excessive polypharmacy (≥10 medicines). Results: Overall, 90% of participants reported use of medicines. Polypharmacy was observed in 31.5% of participants and excessive polypharmacy in 20.1%. Living in a residential institution, and reporting a mental health or neurological condition were strongly associated with polypharmacy and excessive polypharmacy after adjusting for confounders, but age or gender had no significant effect. Conclusions: Polypharmacy was commonplace for older adults with ID and may be partly explained by the high prevalence of multimorbidity reported. Review of appropriateness of medication use is essential, as polypharmacy places ageing people with ID at risk of adverse effects

Multi-plane remote refocussing epifluorescence microscopy to image dynamic Ca2+ events

Rapid imaging of multiple focal planes without sample movement may be achieved through remote refocusing, where imaging is carried out in a plane conjugate to the sample plane. The technique is ideally suited to studying the endothelial and smooth muscle cell layers of blood vessels. These are intrinsically linked through rapid communication and must be separately imaged at a sufficiently high frame rate in order to understand this biologically crucial interaction. We have designed and implemented an epifluoresence-based remote refocussing imaging system that can image each layer at up to 20fps using different dyes and excitation light for each layer, without the requirement for optically sectioning microscopy. A novel triggering system is used to activate the appropriate laser and image acquisition at each plane of interest. Using this method, we are able to achieve axial plane separations down to 15 ????m, with a mean lateral stability of ≤ 0.32 ????m displacement using a 60x, 1.4NA imaging objective and a 60x, 0.7NA reimaging objective. The system allows us to image and quantify endothelial cell activity and smooth muscle cell activity at a high framerate with excellent lateral and good axial resolution without requiring complex beam scanning confocal microscopes, delivering a cost effective solution for imaging two planes rapidly. We have successfully imaged and analysed Ca2+ activity of the endothelial cell layer independently of the smooth muscle layer for several minutes

Cosmogenic 10Be chronology of the last deglaciation of western Ireland, and implications for sensitivity of the Irish Ice Sheet to climate change

Accelerator mass spectrometry (AMS) 14C dates of fossiliferous marine mud identify a readvance of the Irish Ice Sheet from the north and central lowlands of Ireland into the northern Irish Sea Basin during the Killard Point Stadial at ca. 16.5 cal k.y. B.P., with subsequent deglaciation occurring by ca. 15.0–15.5 cal k.y. B.P. Killard Point Stadial moraines have been mapped elsewhere in Ireland but have previously remained undated. Here, we report sixteen 10Be surface exposure dates that constrain the age of retreat of the Killard Point Stadial ice margin from western Ireland. Eight 10Be dates from the Ox Mountains (13.9–18.1 ka) indicate that fi nal deposition of the moraine occurred at 15.6 ± 0.5 ka (mean age, standard error). Eight 10Be dates from Furnace Lough (14.1–17.3 ka, mean age of 15.6 ± 0.4 ka) are statistically indistinguishable from the Ox Mountain samples, suggesting that the moraines were deposited during the same glacial event. Given the agreement between the two age groups, and their common association with a regionally signifi cant moraine system, we combine them to derive a mean age of 15.6 ± 0.3 ka (15.6 ± 1.0 ka with external uncertainty). This age is in excellent agreement with the timing of deglaciation from the Irish Sea Basin (at or older than 15.3 ± 0.2 cal k.y. B.P.) and suggests the onset of near-contemporaneous retreat of the Irish Ice Sheet from its maximum Killard Point Stadial limit. A reconstruction of the ice surface indicates that the Irish Ice Sheet reached a maximum surface elevation of ~500 m over the central Irish Lowlands during the Killard Point Stadial, suggesting a high sensitivity of the ice sheet to small changes in climate