Showing papers by "University of Alberta published in 2000"

Islet Transplantation in Seven Patients with Type 1 Diabetes Mellitus Using a Glucocorticoid-Free Immunosuppressive Regimen

Abstract: Background Registry data on patients with type 1 diabetes mellitus who undergo pancreatic islet transplantation indicate that only 8 percent are free of the need for insulin therapy at one year. Methods Seven consecutive patients with type 1 diabetes and a history of severe hypoglycemia and metabolic instability underwent islet transplantation in conjunction with a glucocorticoid-free immunosuppressive regimen consisting of sirolimus, tacrolimus, and daclizumab. Islets were isolated by ductal perfusion with cold, purified collagenase, digested and purified in xenoprotein-free medium, and transplanted immediately by means of a percutaneous transhepatic portal embolization. Results All seven patients quickly attained sustained insulin independence after transplantation of a mean (±SD) islet mass of 11,547±1604 islet equivalents per kilogram of body weight (median follow-up, 11.9 months; range, 4.4 to 14.9). All recipients required islets from two donor pancreases, and one required a third transplant from tw...

Imaging Cognition II: An Empirical Review of 275 PET and fMRI Studies

Abstract: Positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have been extensively used to explore the functional neuroanatomy of cognitive functions. Here we review 275 PET and fMRI studies of attention (sustained, selective, Stroop, orientation, divided), perception (object, face, space/motion, smell), imagery (object, space/ motion), language (written/spoken word recognition, spoken/ no spoken response), working memory (verbal/numeric, object, spatial, problem solving), semantic memory retrieval (categorization, generation), episodic memory encoding (verbal, object, spatial), episodic memory retrieval (verbal, nonverbal, success, effort, mode, context), priming (perceptual, conceptual), and procedural memory (conditioning, motor, and nonmotor skill learning). To identify consistent activation patterns associated with these cognitive operations, data from 412 contrasts were summarized at the level of cortical Brodmann's areas, insula, thalamus, medial-temporal lobe (including hippocampus), basal ganglia, and cerebellum. For perception and imagery, activation patterns included primary and secondary regions in the dorsal and ventral pathways. For attention and working memory, activations were usually found in prefrontal and parietal regions. For language and semantic memory retrieval, typical regions included left prefrontal and temporal regions. For episodic memory encoding, consistently activated regions included left prefrontal and medial-temporal regions. For episodic memory retrieval, activation patterns included prefrontal, medial-temporal, and posterior midline regions. For priming, deactivations in prefrontal (conceptual) or extrastriate (perceptual) regions were consistently seen. For procedural memory, activations were found in motor as well as in non-motor brain areas. Analysis of regional activations across cognitive domains suggested that several brain regions, including the cerebellum, are engaged by a variety of cognitive challenges. These observations are discussed in relation to functional specialization as well as functional integration.

The surveillant assemblage.

Abstract: George Orwell's 'Big Brother' and Michel Foucault's 'panopticon' have dominated discussion of contemporary developments in surveillance. While such metaphors draw our attention to important attributes of surveillance, they also miss some recent dynamics in its operation. The work of Gilles Deleuze and Felix Guattari is used to analyse the convergence of once discrete surveillance systems. The resultant 'surveillant assemblage' operates by abstracting human bodies from their territorial settings, and separating them into a series of discrete flows. These flows are then reassembled in different locations as discrete and virtual 'data doubles'. The surveillant assemblage transforms the purposes of surveillance and the hierarchies of surveillance, as well as the institution of privacy.

Consumer Decision Making in Online Shopping Environments: The Effects of Interactive Decision Aids

Abstract: Despite the explosive growth of electronic commerce and the rapidly increasing number of consumers who use interactive media such as the World Wide Web for prepurchase information search and online shopping, very little is known about how consumers make purchase decisions in such settings. A unique characteristic of online shopping environments is that they allow vendors to create retail interfaces with highly interactive features. One desirable form of interactivity from a consumer perspective is the implementation of sophisticated tools to assist shoppers in their purchase decisions by customizing the electronic shopping environment to their individual preferences. The availability of such tools, which we refer to as interactive decision aids for consumers, may lead to a transformation of the way in which shoppers search for product information and make purchase decisions. The primary objective of this paper is to investigate the nature of the effects that interactive decision aids may have on consumer decision making in online shopping environments. While making purchase decisions, consumers are often unable to evaluate all available alternatives in great depth and, thus, tend to use two-stage processes to reach their decisions. At the first stage, consumers typically screen a large set of available products and identify a subset of the most promising alternatives. Subsequently, they evaluate the latter in more depth, perform relative comparisons across products on important attributes, and make a purchase decision. Given the different tasks to be performed in such a two-stage process, interactive tools that provide support to consumers in the following respects are particularly valuable: 1 the initial screening of available products to determine which ones are worth considering further, and 2 the in-depth comparison of selected products before making the actual purchase decision. This paper examines the effects of two decision aids, each designed to assist consumers in performing one of the above tasks, on purchase decision making in an online store. The first interactive tool, a recommendation agent RA, allows consumers to more efficiently screen the potentially very large set of alternatives available in an online shopping environment. Based on self-explicated information about a consumer's own utility function attribute importance weights and minimum acceptable attribute levels, the RA generates a personalized list of recommended alternatives. The second decision aid, a comparison matrix CM, is designed to help consumers make in-depth comparisons among selected alternatives. The CM allows consumers to organize attribute information about multiple products in an alternatives × attributes matrix and to have alternatives sorted by any attribute. Based on theoretical and empirical work in marketing, judgment and decision making, psychology, and decision support systems, we develop a set of hypotheses pertaining to the effects of these two decision aids on various aspects of consumer decision making. In particular, we focus on how use of the RA and CM affects consumers' search for product information, the size and quality of their consideration sets, and the quality of their purchase decisions in an online shopping environment. A controlled experiment using a simulated online store was conducted to test the hypotheses. The results indicate that both interactive decision aids have a substantial impact on consumer decision making. As predicted, use of the RA reduces consumers' search effort for product information, decreases the size but increases the quality of their consideration sets, and improves the quality of their purchase decisions. Use of the CM also leads to a decrease in the size but an increase in the quality of consumers' consideration sets, and has a favorable effect on some indicators of decision quality. In sum, our findings suggest that interactive tools designed to assist consumers in the initial screening of available alternatives and to facilitate in-depth comparisons among selected alternatives in an online shopping environment may have strong favorable effects on both the quality and the efficiency of purchase decisions-shoppers can make much better decisions while expending substantially less effort. This suggests that interactive decision aids have the potential to drastically transform the way in which consumers search for product information and make purchase decisions.

Intense High-Energy Proton Beams from Petawatt-Laser Irradiation of Solids

Abstract: An intense collimated beam of high-energy protons is emitted normal to the rear surface of thin solid targets irradiated at 1 PW power and peak intensity 3x10(20) W cm(-2). Up to 48 J ( 12%) of the laser energy is transferred to 2x10(13) protons of energy >10 MeV. The energy spectrum exhibits a sharp high-energy cutoff as high as 58 MeV on the axis of the beam which decreases in energy with increasing off axis angle. Proton induced nuclear processes have been observed and used to characterize the beam.

The Yeast Nuclear Pore Complex: Composition, Architecture, and Transport Mechanism

Abstract: An understanding of how the nuclear pore complex (NPC) mediates nucleocytoplasmic exchange requires a comprehensive inventory of the molecular components of the NPC and a knowledge of how each component contributes to the overall structure of this large molecular translocation machine. Therefore, we have taken a comprehensive approach to classify all components of the yeast NPC (nucleoporins). This involved identifying all the proteins present in a highly enriched NPC fraction, determining which of these proteins were nucleoporins, and localizing each nucleoporin within the NPC. Using these data, we present a map of the molecular architecture of the yeast NPC and provide evidence for a Brownian affinity gating mechanism for nucleocytoplasmic transport.

The sequence manipulation suite: JavaScript programs for analyzing and formatting protein and DNA sequences.

Abstract: JavaScript is an object-based scripting language that can be interpreted by most commonly used Web browsers, including Netscape® Navigator® and Internet Explorer®. In conjunction with HTML form elements, JavaScript can be used to make flexible and easy-to-use applications that can be accessed by anyone connected to the Internet (3). The Sequence Manipulation Suite (http://www.ualberta.ca/~stothard/javascript/) is a collection of freely available JavaScript applications for molecular biologists. It consists of over 30 utilities for analyzing and manipulating sequence data, including the following:

Comparisons and physics basis of tokamak transport models and turbulence simulations

Abstract: The predictions of gyrokinetic and gyrofluid simulations of ion-temperature-gradient(ITG)instability and turbulence in tokamak plasmas as well as some tokamak plasma thermal transportmodels, which have been widely used for predicting the performance of the proposed International Thermonuclear Experimental Reactor (ITER) tokamak [Plasma Physics and Controlled Nuclear Fusion Research, 1996 (International Atomic Energy Agency, Vienna, 1997), Vol. 1, p. 3], are compared. These comparisons provide information on effects of differences in the physics content of the various models and on the fusion-relevant figures of merit of plasma performance predicted by the models. Many of the comparisons are undertaken for a simplified plasma model and geometry which is an idealization of the plasma conditions and geometry in a Doublet III-D [Plasma Physics and Controlled Nuclear Fusion Research, 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. 1, p. 159] high confinement (H-mode) experiment. Most of the models show good agreements in their predictions and assumptions for the linear growth rates and frequencies. There are some differences associated with different equilibria. However, there are significant differences in the transport levels between the models. The causes of some of the differences are examined in some detail, with particular attention to numerical convergence in the turbulence simulations (with respect to simulation mesh size, system size and, for particle-based simulations, the particle number). The implications for predictions of fusion plasma performance are also discussed.

Predictors of outcome in patients with acute coronary syndromes without persistent ST-segment elevation. Results from an international trial of 9461 patients. The PURSUIT Investigators.

Abstract: BACKGROUND: Appropriate treatment policies should include an accurate estimate of a patient's baseline risk. Risk modeling to date has been underutilized in patients with acute coronary syndromes without persistent ST-segment elevation. METHODS AND RESULTS: We analyzed the relation between baseline characteristics and the 30-day incidence of death and the composite of death or myocardial (re)infarction in 9461 patients with acute coronary syndromes without persistent ST-segment elevation enrolled in the PURSUIT trial [Platelet glycoprotein IIb/IIIa in Unstable angina: Receptor Suppression Using Integrilin (eptifibatide) Therapy]. Variables examined included demographics, history, hemodynamic condition, and symptom duration. Risk models were created with multivariable logistic regression and validated by bootstrapping techniques. There was a 3.6% mortality rate and 11.4% infarction rate by 30 days. More than 20 significant predictors for mortality and for the composite end point were identified. The most important baseline determinants of death were age (adjusted chi(2)=95), heart rate (chi(2)=32), systolic blood pressure (chi(2)=20), ST-segment depression (chi(2)=20), signs of heart failure (chi(2)=18), and cardiac enzymes (chi(2)=15). Determinants of mortality were generally also predictive of death or myocardial (re)infarction. Differences were observed, however, in the relative prognostic importance of predictive variables for mortality alone or the composite end point; for example, sex was a more important determinant of the composite end point (chi(2)=21) than of death alone (chi(2)=10). The accuracy of the prediction of the composite end point was less than that of mortality (C-index 0.67 versus 0.81). CONCLUSIONS: The occurrence of adverse events after presentation with acute coronary syndromes is affected by multiple factors. These factors should be considered in the clinical decision-making process.

Shiga-like toxins are neutralized by tailored multivalent carbohydrate ligands

Abstract: The diseases caused by Shiga and cholera toxins account for the loss of millions of lives each year. Both belong to the clinically significant subset of bacterial AB5 toxins consisting of an enzymatically active A subunit that gains entry to susceptible mammalian cells after oligosaccharide recognition by the B5 homopentamer. Therapies might target the obligatory oligosaccharide-toxin recognition event, but the low intrinsic affinity of carbohydrate-protein interactions hampers the development of low-molecular-weight inhibitors. The toxins circumvent low affinity by binding simultaneously to five or more cell-surface carbohydrates. Here we demonstrate the use of the crystal structure of the B5 subunit of Escherichia coli O157:H7 Shiga-like toxin I (SLT-I) in complex with an analogue of its carbohydrate receptor to design an oligovalent, water-soluble carbohydrate ligand (named STARFISH), with subnanomolar inhibitory activity. The in vitro inhibitory activity is 1-10-million-fold higher than that of univalent ligands and is by far the highest molar activity of any inhibitor yet reported for Shiga-like toxins I and II. Crystallography of the STARFISH/Shiga-like toxin I complex explains this activity. Two trisaccharide receptors at the tips of each of five spacer arms simultaneously engage all five B subunits of two toxin molecules.

Methodological Issues in the Content Analysis of Computer Conference Transcripts

Abstract: This paper discusses the potential and the methodological challenges of analyzing computer conference transcripts using quantitative content analysis. The paper is divided into six sections, which discuss: criteria for content analysis, research designs, types of content, units of analysis, ethical issues, and software to aid analysis. The discussion is supported with a survey of 19 commonly referenced studies published during the last decade. The paper is designed to assist researchers in using content analysis to further the understanding of teaching and learning using computer conferencing. SCENARIO Professor Jones has just completed her first university course delivered entirely on- line. The 13-week semester class has left Jones in a state of mild exhaustion. However, the course is finished, the marks have been assigned, and now, thinks Jones, time for some reflection, analysis and perhaps a publishable paper. Jones smiles, confident in the knowledge that the complete transcript of messages exchanged during the course has been captured in machine-readable format. She feels that this accessible data will confirm her hypothesis that students in the on-line course had engaged in much higher levels of discourse and discussion than any she had experienced in ten years of face-to-face instruction. Further, she is interested in investigating the impact of the collaborative learning activity that she instituted in the middle of the course. Jones is quickly disappointed. The 13-week discussion generated 950 messages. Merely reading them takes her four days. Attempts at cutting and pasting illustrations of higher level thinking into a word processor, have resulted in a hodge-podge of decontextualized quotations, each disparate enough to have Professor Jones questioning her own definitions of higher order thinking. Realizing that the analysis is going nowhere, Professor Jones goes back to the literature and finds a set of criteria laid down by an expert in the field that define the broad areas of thinking skills she sees being developed in the transcripts. Heartened, but now running out of time Professor Jones hires two graduate students to review the messages and identify the incidents of higher order thinking as defined by the expert. Two weeks later, the students report their results: not only have they failed to agree on 70% of the categorizations, but one student has identified 2032 incidents in the transcript, while the other has found only 635 incidents. To add to her misery, Professor Jones also learns that her University's ethics committee, concerned with the large increase in use of computer conferencing for credit courses, has ruled that without informed consent from students, her analysis does not conform with the guidelines of the university's ethical research policy. Feeling overwhelmed and depressed, Professor Jones returns to the educational literature once again, only to find that most of the methodological issues she has been dealing with have not been addressed by major researchers in the field. She also finds that

The Antianginal Drug Trimetazidine Shifts Cardiac Energy Metabolism From Fatty Acid Oxidation to Glucose Oxidation by Inhibiting Mitochondrial Long-Chain 3-Ketoacyl Coenzyme A Thiolase

Abstract: Trimetazidine is a clinically effective antianginal agent that has no negative inotropic or vasodilator properties. Although it is thought to have direct cytoprotective actions on the myocardium, the mechanism(s) by which this occurs is as yet undefined. In this study, we determined what effects trimetazidine has on both fatty acid and glucose metabolism in isolated working rat hearts and on the activities of various enzymes involved in fatty acid oxidation. Hearts were perfused with Krebs-Henseleit solution containing 100 microU/mL insulin, 3% albumin, 5 mmol/L glucose, and fatty acids of different chain lengths. Both glucose and fatty acids were appropriately radiolabeled with either (3)H or (14)C for measurement of glycolysis, glucose oxidation, and fatty acid oxidation. Trimetazidine had no effect on myocardial oxygen consumption or cardiac work under any aerobic perfusion condition used. In hearts perfused with 5 mmol/L glucose and 0.4 mmol/L palmitate, trimetazidine decreased the rate of palmitate oxidation from 488+/-24 to 408+/-15 nmol x g dry weight(-1) x minute(-1) (P<0.05), whereas it increased rates of glucose oxidation from 1889+/-119 to 2378+/-166 nmol x g dry weight(-1) x minute(-1) (P<0.05). In hearts subjected to low-flow ischemia, trimetazidine resulted in a 210% increase in glucose oxidation rates. In both aerobic and ischemic hearts, glycolytic rates were unaltered by trimetazidine. The effects of trimetazidine on glucose oxidation were accompanied by a 37% increase in the active form of pyruvate dehydrogenase, the rate-limiting enzyme for glucose oxidation. No effect of trimetazidine was observed on glycolysis, glucose oxidation, fatty acid oxidation, or active pyruvate dehydrogenase when palmitate was substituted with 0.8 mmol/L octanoate or 1.6 mmol/L butyrate, suggesting that trimetazidine directly inhibits long-chain fatty acid oxidation. This reduction in fatty acid oxidation was accompanied by a significant decrease in the activity of the long-chain isoform of the last enzyme involved in fatty acid beta-oxidation, 3-ketoacyl coenzyme A (CoA) thiolase activity (IC(50) of 75 nmol/L). In contrast, concentrations of trimetazidine in excess of 10 and 100 micromol/L were needed to inhibit the medium- and short-chain forms of 3-ketoacyl CoA thiolase, respectively. Previous studies have shown that inhibition of fatty acid oxidation and stimulation of glucose oxidation can protect the ischemic heart. Therefore, our data suggest that the antianginal effects of trimetazidine may occur because of an inhibition of long-chain 3-ketoacyl CoA thiolase activity, which results in a reduction in fatty acid oxidation and a stimulation of glucose oxidation.

Brief Electrical Stimulation Promotes the Speed and Accuracy of Motor Axonal Regeneration

Abstract: Functional recovery is often poor despite the capacity for axonal regeneration in the peripheral nervous system and advances in microsurgical technique. Regeneration of axons in mixed nerve into inappropriate pathways is a major contributing factor to this failure. In this study, we use the rat femoral nerve model of transection and surgical repair to evaluate (1) the effect of nerve transection on the speed of regeneration and the generation of motor-sensory specificity, (2) the efficacy of electrical stimulation in accelerating axonal regeneration and promoting the reinnervation of appropriate muscle pathways by femoral motor nerves, and (3) the mechanism of action of electrical stimulation. Using the retrograde neurotracers fluorogold and fluororuby to backlabel motoneurons that regenerate axons into muscle and cutaneous pathways, we found the following. (1) There is a very protracted period (10 weeks) of axonal outgrowth that adds substantially to the delay in axonal regeneration (staggered regeneration). This process of staggered regeneration is associated with preferential motor reinnervation (PMR). (2) One hour to 2 weeks of 20 Hz continuous electrical stimulation of the parent axons proximal to the repair site dramatically reduces this period (to 3 weeks) and accelerates PMR. (3) The positive effect of short-term electrical stimulation is mediated via the cell body, implicating an enhanced growth program. The effectiveness of such a short-period low-frequency electrical stimulation suggests a new therapeutic approach to accelerate nerve regeneration after injury and, in turn, improve functional recovery.

A Controlled Trial of a Critical Pathway for Treatment of Community-Acquired Pneumonia

Abstract: ContextLarge variations exist among hospitals in the use of treatment resources for community-acquired pneumonia (CAP). Lack of a common approach to the diagnosis and treatment of CAP has been cited as an explanation for these variations.ObjectiveTo determine if use of a critical pathway improves the efficiency of treatment for CAP without compromising the well-being of patients.DesignMulticenter controlled clinical trial with cluster randomization and up to 6 weeks of follow-up.SettingNineteen teaching and community hospitals in Canada.PatientsA total of 1743 patients with CAP presenting to the emergency department at 1 of the participating institutions between January 1 and July 31, 1998.InterventionHospitals were assigned to continue conventional management (n = 10) or implement the critical pathway (n = 9), which consisted of a clinical prediction rule to guide the admission decision, levofloxacin therapy, and practice guidelines.Main Outcome MeasuresEffectiveness of the critical pathway, as measured by health-related quality of life on the Short-Form 36 Physical Component Summary (SF-36 PCS) scale at 6 weeks; and resource utilization, as measured by the number of bed days per patient managed (BDPM).ResultsQuality of life and the occurrence of complications, readmission, and mortality were not different for the 2 strategies; the 1-sided 95% confidence limit of the between-group difference in the SF-36 PCS change score was 2.4 points, which was within a predefined 3-point boundary for equivalence. Pathway use was associated with a 1.7-day reduction in BDPM (4.4 vs 6.1 days; P = .04) and an 18% decrease in the admission of low-risk patients (31% vs 49%; P = .01). Although inpatients at critical pathway hospitals had more severe disease, they required 1.7 fewer days of intravenous therapy (4.6 vs 6.3 days; P = .01) and were more likely to receive treatment with a single class of antibiotic (64% vs 27%; P<.001).ConclusionIn this study, implementation of a critical pathway reduced the use of institutional resources without causing adverse effects on the well-being of patients.

Effect of eliminating compensation for pain and suffering on the outcome of insurance claims for whiplash injury

Abstract: Background and Methods The incidence and prognosis of whiplash injury from motor vehicle collisions may be related to eligibility for compensation for pain and suffering. On January 1, 1995, the tort-compensation system for traffic injuries, which included payments for pain and suffering, in Saskatchewan, Canada, was changed to a no-fault system, which did not include such payments. To determine whether this change was associated with a decrease in claims and improved recovery after whiplash injury, we studied a population-based cohort of persons who filed insurance claims for traffic injuries between July 1, 1994, and December 31, 1995. Results Of 9006 potentially eligible claimants, 7462 (83 percent) met our criteria for whiplash injury. The six-month cumulative incidence of claims was 417 per 100,000 persons in the last six months of the tort system, as compared with 302 and 296 per 100,000, respectively, in the first and second six-month periods of the no-fault system. The incidence of claims was high...

A brief overview of the present status of the mechanisms involved in electrospray mass spectrometry

Abstract: A brief account of the mechanisms by which ions in solution are converted to ions in the gas phase is given on the basis of information available in the literature and the four companion articles on electrospray mass spectrometry (ESMS) in this issue. The following stages/phenomena are described: (a) production of the charged droplets at the ES capillary tip; (b) evolution of the charged droplets due to solvent evaporation and droplet fission caused by Coulombic repulsion of the charges on the droplets; production of the gas phase ion from very small charged droplets by the charge residue model (CRM) or the ion evaporation method (IEM); (c) dependence of the sensitivity in ESMS on the chemical nature of the analyte and its concentration as well as on the concentration of other electrolytes that are present in the solution; qualitative predictions on the sensitivity of the analyte based on the surface activity of the analyte ions; (d) relationship between ions produced in the gas phase and original ions present in the solution; and (e) globular proteins. Much of the information presented in (a)-(e) has been available for some time in the literature. However some significant advances are relatively recent. Recent results by de la Mora and co-workers, including their contribution in this Special Feature, provide very strong evidence that small ions (in distinction from macroions such as bio-macroions) are produced by IEM. On the other hand, macroions and particularly the polyprotonated globular proteins are produced by CRM. Also noteworthy is the development of an equation by Enke with which the observed relative ion signal intensities of the gas-phase ions produced can be predicted on the basis of the ion concentration in solution over a wide concentration range. The recognition that the sensitivity of organic analyte ions can be qualitatively predicted on the basis of the hydrophilicity or hydrophobicity of the part of the molecule that is not part of the charged (ionic) group and affects the surface activity of the ionic species is also noteworthy and a very useful relatively recent development.

Canadian Guidelines for the Initial Management of Community-Acquired Pneumonia: An Evidence-Based Update by the Canadian Infectious Diseases Society and the Canadian Thoracic Society

Abstract: Lionel A Mandell MD FRCPC1, Thomas J Marrie MD FRCPC2, Ronald F Grossman MD FRCPC FACP3, Anthony W Chow MD FRCPC FACP4, Robert H Hyland MD FRCPC5, and the Canadian CAP Working Group* McMaster University, Hamilton, Ontario; Dalhousie University, Halifax, Nova Scotia; QEII Health Sciences Centre, Halifax, Nova Scotia; University of British Columbia, Vancouver, British Columbia; St Michael’s Hospital, Toronto, Ontario

Occurrence, causes, and outcome of delirium in patients with advanced cancer: a prospective study.

Abstract: Context Delirium impedes communication and contributes to symptom distress in patients with advanced cancer. There are few prospective data on the reversal of delirium in this population. Objectives To evaluate the occurrence, precipitating factors, and reversibility of delirium in patients with advanced cancer. Design Prospective serial assessment in a consecutive cohort of 113 patients with advanced cancer. Precipitating factors were examined using standardized criteria; 104 patients met eligibility criteria. Setting Acute palliative care unit in a university-affiliated teaching hospital. Main Outcome Measures Delirium occurrence and reversal rates, duration, and patient survival. Strengths of association of various precipitating factors with reversal were expressed as hazard ratios (HRs) in univariate and multivariate analyses. Results On admission, delirium was diagnosed in 44 patients (42%), and of the remaining 60, delirium developed in 27 (45%). Reversal of delirium occurred in 46 (49%) of 94 episodes in 71 patients. Terminal delirium occurred in 46 (88%) of the 52 deaths. In univariate analysis, psychoactive medications, predominantly opioids (HR, 8.85; 95% confidence interval [CI], 2.13-36.74), and dehydration (HR, 2.35; 95% CI, 1.20-4.62) were associated with reversibility. Hypoxic encephalopathy (HR, 0.39; 95% CI, 0.19-0.80) and metabolic factors (HR, 0.44; 95% CI, 0.21-0.91) were associated with nonreversibility. In mulitivariate analysis, psychoactive medications (HR, 6.65; 95% CI, 1.49-29.62), hypoxic encephalopathy (HR, 0.32; 95% CI, 0.15-0.70), and nonrespiratory infection (HR, 0.23; 95% CI, 0.08-0.64) had independent associations. Patients with delirium had poorer survival rates than controls ( P Conclusions Delirium is a frequent, multifactorial complication in advanced cancer.Despite its terminal presentation in most patients, delirium is reversible in approximately 50% of episodes. Delirium precipitated by opioids and other psychoactive medications and dehydration is frequently reversible with change of opioid or dose reduction, discontinuation of unnecessary psychoactive medication, or hydration, respectively.

A comparison of methotrexate with placebo for the maintenance of remission in Crohn's disease. North American Crohn's Study Group Investigators.

Abstract: Background Patients with Crohn's disease often have relapses. Better treatments are needed for the maintenance of remission. Although methotrexate is an effective short-term treatment for Crohn's disease, its role in maintaining remissions is not known. Methods We conducted a double-blind, placebo-controlled, multicenter study of patients with chronically active Crohn's disease who had entered remission after 16 to 24 weeks of treatment with 25 mg of methotrexate given intramuscularly once weekly. Patients were randomly assigned to receive either methotrexate at a dose of 15 mg intramuscularly once weekly or placebo for 40 weeks. No other treatments for Crohn's disease were permitted. We compared the efficacy of treatment by analyzing the proportion of patients who remained in remission at week 40. Remission was defined as a score of 150 or less on the Crohn's Disease Activity Index. Results Forty patients received methotrexate, and 36 received placebo. At week 40, 26 patients (65 percent) were in remissi...

Vanishing Voices: The Extinction of the World's Languages

Abstract: 1. Where have All the Languages Gone 2. A World of Diversity 3. Lost Words / Lost Worlds 4. The Ecology of Language 5. The Biological Wave 6. The Economic Wave 7. Why Something Should be Done 8. Sustainable Futures References and Further Reading Bibliography Index

Partial encryption of compressed images and videos

Abstract: The increased popularity of multimedia applications places a great demand on efficient data storage and transmission techniques. Network communication, especially over a wireless network, can easily be intercepted and must be protected from eavesdroppers. Unfortunately, encryption and decryption are slow, and it is often difficult, if not impossible, to carry out real-time secure image and video communication and processing. Methods have been proposed to combine compression and encryption together to reduce the overall processing time, but they are either insecure or too computationally intensive. We propose a novel solution called partial encryption, in which a secure encryption algorithm is used to encrypt only part of the compressed data. Partial encryption is applied to several image and video compression algorithms in this paper. Only 13-27% of the output from quadtree compression algorithms is encrypted for typical images, and less than 2% is encrypted for 512/spl times/512 images compressed by the set partitioning in hierarchical trees (SPIHT) algorithm. The results are similar for video compression, resulting in a significant reduction in encryption and decryption time. The proposed partial encryption schemes are fast, secure, and do not reduce the compression performance of the underlying compression algorithm.

Insulinotropic glucagon-like peptide 1 agonists stimulate expression of homeodomain protein IDX-1 and increase islet size in mouse pancreas.

Abstract: Diabetes is caused by a failure of the pancreas to produce insulin in amounts sufficient to meet the body's needs. A hallmark of diabetes is an absolute (type 1) or relative (type 2) reduction in the mass of pancreatic beta-cells that produce insulin. Mature beta-cells have a lifespan of approximately 48-56 days (rat) and are replaced by the replication of preexisting beta-cells and by the differentiation and proliferation of new beta-cells (neogenesis) derived from the pancreatic ducts. Here, we show that the insulinotropic hormone glucagon-like peptide (GLP)-1, which is produced by the intestine, enhances the pancreatic expression of the homeodomain transcription factor IDX-1 that is critical for pancreas development and the transcriptional regulation of the insulin gene. Concomitantly, GLP-1 administered to diabetic mice stimulates insulin secretion and effectively lowers their blood sugar levels. GLP-1 also enhances beta-cell neogenesis and islet size. Thus, in addition to stimulating insulin secretion, GLP-1 stimulates the expression of the transcription factor IDX-1 while stimulating beta-cell neogenesis and may thereby be an effective treatment for diabetes.

Why Do Patients With Atrial Fibrillation Not Receive Warfarin

Abstract: Atrial fibrillation (AF) is a growing public health problem associated with significant morbidity and mortality. Numerous randomized controlled trials of warfarin have conclusively demonstrated that long-term anticoagulation therapy can reduce the risk for stroke by approximately 68% per year in patients with nonvalvular AF, and even more in patients with valvular AF. However, available data show that of those patients with AF and no contraindication to warfarin therapy, only 15% to 44% are prescribed warfarin. Our literature review has identified patient-, physician-, and health care system‐related barriers to warfarin prescription. However, the relative importance of these specific barriers remains unknown. Further work is needed to understand the discrepancy between the randomized controlled trial evidence and clinical practice patterns. Arch Intern Med. 2000;160:41-46

Ignore fishers’ knowledge and miss the boat

Abstract: We describe five examples of how, by ignoring fishers’ ecological knowledge (FEK), marine researchers and resource managers may put fishery resources at risk, or unnecessarily compromise the welfare of resource users. Fishers can provide critical information on such things as interannual, seasonal, lunar, diel, tide-related and habitat-related differences in behaviour and abundance of target species, and on how these influence fishing strategies. Where long-term data sets are unavailable, older fishers are also often the only source of information on historical changes in local marine stocks and in marine environmental conditions. FEK can thus help improve management of target stocks and rebuild marine ecosystems. It can play important roles in the siting of marine protected areas and in environmental impact assessment. The fact that studying FEK does not meet criteria for acceptable research advanced by some marine biologists highlights the inadequacy of those criteria.