5,993 research outputs found
Antinuclear antibodies (ANA) in chronic hepatitis C virus infection: correlates of positivity and clinical relevance.
We examined correlates of antinuclear antibody (ANA) positivity (ANA+) in individuals with chronic hepatitis C virus (HCV) infection and the effect of positivity on clinical outcome of HCV. Pretreatment sera from 645 patients from three centres in Sweden (n = 225), the UK (n = 207) and Italy (n = 213) were evaluated by indirect immunofluorescence on Hep-2 cells for ANA pattern and titre by a single laboratory. Liver biopsies were all scored by one pathologist. A total of 258 patients were subsequently treated with interferon monotherapy. There was a significant difference in the prevalence of ANA (1:40) by geographic location: Lund 4.4%, London 8.7%, Padova 10.3% [odds ratio (OR) = 0.66; 95% CI: 0.46-0.94; P = 0.023]. Duration of HCV infection, age at infection, current age, route of infection, viral genotype, alcohol consumption, fibrosis stage and inflammatory score were not correlated with ANA+ or ANA pattern. Female gender was correlated with ANA+ and this association persisted in multivariable analyses (OR = 3.0; P = 0.002). Increased plasma cells were observed in the liver biopsies of ANA-positive individuals compared with ANA-negative individuals, while a trend towards decreased lymphoid aggregates was observed [hazard ratio (HR) = 9.0, P = 0.037; HR = 0.291, P = 0.118, respectively]. No correlations were observed between ANA positivity and nonresponse to therapy (OR = 1.4; P = 0.513), although ANA+ was correlated with faster rates of liver fibrosis, this was not statistically significant (OR = 1.8; P = 0.1452). Low titre ANA+ should not be a contraindication for interferon treatment. Our observation of increased plasma cells in ANA+ biopsies might suggest B-cell polyclonal activity with a secondary clinical manifestation of increased serum immunoglobulins
Feature Selection of Post-Graduation Income of College Students in the United States
This study investigated the most important attributes of the 6-year
post-graduation income of college graduates who used financial aid during their
time at college in the United States. The latest data released by the United
States Department of Education was used. Specifically, 1,429 cohorts of
graduates from three years (2001, 2003, and 2005) were included in the data
analysis. Three attribute selection methods, including filter methods, forward
selection, and Genetic Algorithm, were applied to the attribute selection from
30 relevant attributes. Five groups of machine learning algorithms were applied
to the dataset for classification using the best selected attribute subsets.
Based on our findings, we discuss the role of neighborhood professional degree
attainment, parental income, SAT scores, and family college education in
post-graduation incomes and the implications for social stratification.Comment: 14 pages, 6 tables, 3 figure
Seizure initiation in infantile spasms vs. focal seizures: proposed common cellular mechanisms
Infantile spasms (IS) and seizures with focal onset have different clinical expressions, even when electroencephalography (EEG) associated with IS has some degree of focality. Oddly, identical pathology (with, however, age-dependent expression) can lead to IS in one patient vs. focal seizures in another or even in the same, albeit older, patient. We therefore investigated whether the cellular mechanisms underlying seizure initiation are similar in the two instances: spasms vs. focal. We noted that in-common EEG features can include (i) a background of waves at alpha to delta frequencies; (ii) a period of flattening, lasting about a second or more – the electrodecrement (ED); and (iii) often an interval of very fast oscillations (VFO; ~70 Hz or faster) preceding, or at the beginning of, the ED. With IS, VFO temporally coincides with the motor spasm. What is different between the two conditions is this: with IS, the ED reverts to recurring slow waves, as occurring before the ED, whereas with focal seizures the ED instead evolves into an electrographic seizure, containing high-amplitude synchronized bursts, having superimposed VFO. We used in vitro data to help understand these patterns, as such data suggest cellular mechanisms for delta waves, for VFO, for seizure-related burst complexes containing VFO, and, more recently, for the ED. We propose a unifying mechanistic hypothesis – emphasizing the importance of brain pH – to explain the commonalities and differences of EEG signals in IS versus focal seizures
The cost of operating a national renal/pancreas transplant unit, CHERE Discussion Paper No 13
In June 1990 the Australian Health Ministers endorsed a policy, known as the Nationally Funded Centres (NFC) programme, aimed at providing new and developing technologies in a coordinated and planned way on a national basis. The principal objective was to ensure that such technologies were available to the Australian population on an equitable and cost effective basis. A reference group of the NFC was established, charged with appraising the annual budgets for each NFC. For this a detailed independent costing was necessary, which comprehensively detailed all resources used in a manner allowing funds to be allocated between cost centres. The objective of this study was to prepare estimates of the cost of renal/pancreas transplant services at Westmead hospital under the auspices of the NFC programme. The Pancreas Transplant Research Group at Westmead has, throughout the 1980s, been involved in developing pancreas transplantation in the laboratory and bringing it into clinical practice. The Renal Unit performed its first renal/pancreas combined transplant in July 1987 and has, to date, performed approximately 32 such transplants. The costing was based on a predicted patient throughput of 14 for 1993; although only 10 patients actually proceed to transplantation. The results were an average direct cost to the hospital of 2,660, for patients who progress no further than assessment, to 9,948. Overheads averaged 887, per patient. Thus, the predicted total cost of running the Unit for 1993 was 98,397.Renal/pancreas transplant unit, costs
Identifying people at higher risk of melanoma across the U.K.: a primary-care-based electronic survey
BACKGROUND: Melanoma incidence is rising rapidly worldwide among white populations. Defining higher-risk populations using risk prediction models may help targeted screening and early detection approaches. OBJECTIVES: To assess the feasibility of identifying people at higher risk of melanoma using the Williams self-assessed clinical risk estimation model in U.K. primary care. METHODS: We recruited participants from the waiting rooms of 22 general practices covering a total population of > 240 000 in three U.K. regions: Eastern England, North East Scotland and North Wales. Participants completed an electronic questionnaire using tablet computers. The main outcome was the mean melanoma risk score using the Williams melanoma risk model. RESULTS: Of 9004 people approached, 7742 (86%) completed the electronic questionnaire. The mean melanoma risk score for the 7566 eligible participants was 17·15 ± 8·51, with small regional differences [lower in England compared with Scotland (P = 0·001) and Wales (P < 0·001), mainly due to greater freckling and childhood sunburn among Scottish and Welsh participants]. After weighting to the age and sex distribution, different potential cut-offs would allow between 4% and 20% of the population to be identified as higher risk, and those groups would contain 30% and 60%, respectively of those likely to develop melanoma. CONCLUSIONS: Collecting data on the melanoma risk profile of the general population in U.K. primary care is both feasible and acceptable for patients in a general practice setting, and provides opportunities for new methods of real-time risk assessment and risk stratified cancer interventions
Low-frequency cortical activity is a neuromodulatory target that tracks recovery after stroke.
Recent work has highlighted the importance of transient low-frequency oscillatory (LFO; <4 Hz) activity in the healthy primary motor cortex during skilled upper-limb tasks. These brief bouts of oscillatory activity may establish the timing or sequencing of motor actions. Here, we show that LFOs track motor recovery post-stroke and can be a physiological target for neuromodulation. In rodents, we found that reach-related LFOs, as measured in both the local field potential and the related spiking activity, were diminished after stroke and that spontaneous recovery was closely correlated with their restoration in the perilesional cortex. Sensorimotor LFOs were also diminished in a human subject with chronic disability after stroke in contrast to two non-stroke subjects who demonstrated robust LFOs. Therapeutic delivery of electrical stimulation time-locked to the expected onset of LFOs was found to significantly improve skilled reaching in stroke animals. Together, our results suggest that restoration or modulation of cortical oscillatory dynamics is important for the recovery of upper-limb function and that they may serve as a novel target for clinical neuromodulation
A preliminary cost utility analysis of adjuvant chemotherapy for resected colonic carcinoma, CHERE Discussion Paper No 15
In 1990, a study was published (Moertel CG, et al 1990) which recommended a new treatment standard for colon cancer: a 52 week course of adjuvant chemotherapy. The study recommended that such a course of chemotherapy administered after surgical resection could increase five year survival from 55% to 71%. However, this recommendation raised several concerns, particularly about the quality of life of patients undergoing such a long course of chemotherapy and the costs to the health care system of such a prolonged therapy. This paper sought to address both of these issues in the context of an economic evaluation. The cost of surgery plus chemotherapy was estimated and compared with the cost of surgery alone. Descriptions of quality of life were developed from interviews with patients and health professionals, and the time trade off technique was then used to derive utility weights (from a small sample of 16) which were used to adjust length of life to reflect quality, in terms of a "quality adjusted life year" (QALY). Expected survival with and without chemotherapy was based on published data. Chemotherapy increased the total cost of treating a patient with colon cancer by 6,012 to 2,920. Incorporating quality of life reduced this gain to 0.36 QALYs. Thus the cost per QALY gained was $19,472. The results of this analysis are only tentative, as the quality of life descriptions were not measured over time, but from a cross sectional survey of patients, and the valuations of health states were derived from a small sample. However, the results do demonstrate the importance of quality of life in the evaluation of cancer treatment.cost utility analysis, chemotherapy, colon cancer
Social networks and labour productivity in Europe: An empirical investigation
This paper uses firm-level data recorded in the AMADEUS database to
investigate the distribution of labour productivity in different European
countries. We find that the upper tail of the empirical productivity
distributions follows a decaying power-law, whose exponent is obtained
by a semi-parametric estimation technique recently developed by Clementi et al.
(2006). The emergence of "fat tails" in productivity distribution has already
been detected in Di Matteo et al. (2005) and explained by means of a model of
social network. Here we show that this model is tested on a broader sample of
countries having different patterns of social network structure. These
different social attitudes, measured using a social capital indicator, reflect
in the power-law exponent estimates, verifying in this way the existence of
linkages among firms' productivity performance and social network.Comment: LaTeX2e; 18 pages with 3 figures; Journal of Economic Interaction and
Coordination, in pres
Who bullies whom at a garden feeder? Interspecific agonistic interactions of small passerines during a cold winter
Interspecific agonistic interactions are important
selective factors for maintaining ecological niches of
different species, but their outcome is difficult to predict
a priori. Here, we examined the direction and intensity of
interspecific interactions in an assemblage of small passerines
at a garden feeder, focussing on three finch species
of various body sizes. We found that large and mediumsized
birds usually initiated and won agonistic interactions
with smaller species. Also, the frequency of fights increased
with decreasing differences in body size between
the participants. Finally, the probability of engaging in a
fight increased with the number of birds at the feeder
Evaluating the effects of bilingual traffic signs on driver performance and safety
Variable Message Signs (VMS) can provide immediate and relevant information to road users and bilingual VMS can provide great flexibility in countries where a significant proportion of the population speak an alternative language to the majority. The study reported here evaluates the effect of various bilingual VMS configurations on driver behaviour and safety. The aim of the study was to determine whether or not the visual distraction associated with bilingual VMS signs of different configurations (length, complexity) impacted on driving performance. A driving simulator was used to allow full control over the scenarios, road environment and sign configuration and both longitudinal and lateral driver performance was assessed. Drivers were able to read one and two-line monolingual signs and two-line bilingual signs without disruption to their driving behaviour. However, drivers significantly reduced their speed in order to read four-line monolingual and four-line bilingual signs, accompanied by an increase in headway to the vehicle in front. This implies that drivers are possibly reading the irrelevant text on the bilingual sign and various methods for reducing this effect are discussed
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