Showing papers by "University of Ottawa published in 2008"

Genome-wide association studies for complex traits: consensus, uncertainty and challenges

Abstract: The past year has witnessed substantial advances in understanding the genetic basis of many common phenotypes of biomedical importance. These advances have been the result of systematic, well-powered, genome-wide surveys exploring the relationships between common sequence variation and disease predisposition. This approach has revealed over 50 disease-susceptibility loci and has provided insights into the allelic architecture of multifactorial traits. At the same time, much has been learned about the successful prosecution of association studies on such a scale. This Review highlights the knowledge gained, defines areas of emerging consensus, and describes the challenges that remain as researchers seek to obtain more complete descriptions of the susceptibility architecture of biomedical traits of interest and to translate the information gathered into improvements in clinical management.

A comparison of direct versus self-report measures for assessing physical activity in adults: a systematic review

Abstract: Accurate assessment is required to assess current and changing physical activity levels, and to evaluate the effectiveness of interventions designed to increase activity levels. This study systematically reviewed the literature to determine the extent of agreement between subjectively (self-report e.g. questionnaire, diary) and objectively (directly measured; e.g. accelerometry, doubly labeled water) assessed physical activity in adults. Eight electronic databases were searched to identify observational and experimental studies of adult populations. Searching identified 4,463 potential articles. Initial screening found that 293 examined the relationship between self-reported and directly measured physical activity and met the eligibility criteria. Data abstraction was completed for 187 articles, which described comparable data and/or comparisons, while 76 articles lacked comparable data or comparisons, and a further 30 did not meet the review's eligibility requirements. A risk of bias assessment was conducted for all articles from which data was abstracted. Correlations between self-report and direct measures were generally low-to-moderate and ranged from -0.71 to 0.96. No clear pattern emerged for the mean differences between self-report and direct measures of physical activity. Trends differed by measure of physical activity employed, level of physical activity measured, and the gender of participants. Results of the risk of bias assessment indicated that 38% of the studies had lower quality scores. The findings suggest that the measurement method may have a significant impact on the observed levels of physical activity. Self-report measures of physical activity were both higher and lower than directly measured levels of physical activity, which poses a problem for both reliance on self-report measures and for attempts to correct for self-report – direct measure differences. This review reveals the need for valid, accurate and reliable measures of physical activity in evaluating current and changing physical activity levels, physical activity interventions, and the relationships between physical activity and health outcomes.

Regional Variation in Out-of-Hospital Cardiac Arrest Incidence and Outcome

Abstract: Context The health and policy implications of regional variation in incidence and outcome of out-of-hospital cardiac arrest remain to be determined. Objective To evaluate whether cardiac arrest incidence and outcome differ across geographic regions. Design, Setting, and Patients Prospective observational study (the Resuscitation Outcomes Consortium) of all out-of-hospital cardiac arrests in 10 North American sites (8 US and 2 Canadian) from May 1, 2006, to April 30, 2007, followed up to hospital discharge, and including data available as of June 28, 2008. Cases (aged 0-108 years) were assessed by organized emergency medical services (EMS) personnel, did not have traumatic injury, and received attempts at external defibrillation or chest compressions or resuscitation was not attempted. Census data were used to determine rates adjusted for age and sex. Main Outcome Measures Incidence rate, mortality rate, case-fatality rate, and survival to discharge for patients assessed or treated by EMS personnel or with an initial rhythm of ventricular fibrillation. Results Among the 10 sites, the total catchment population was 21.4 million, and there were 20 520 cardiac arrests. A total of 11 898 (58.0%) had resuscitation attempted; 2729 (22.9% of treated) had initial rhythm of ventricular fibrillation or ventricular tachycardia or rhythms that were shockable by an automated external defibrillator; and 954(4.6% of total) were discharged alive. The median incidence of EMS-treated cardiac arrest across sites was 52.1 (interquartile range [IQR], 48.0-70.1) per 100 000 population; survival ranged from 3.0% to 16.3%, with a median of 8.4% (IQR, 5.4%-10.4%). Median ventricular fibrillation incidence was 12.6 (IQR, 10.6-5.2) per 100 000 population; survival ranged from 7.7% to 39.9%, with a median of 22.0% (IQR, 15.0%-24.4%), with significant differences across sites for incidence and survival (P Conclusion In this study involving 10 geographic regions in North America, there were significant and important regional differences in out-of-hospital cardiac arrest incidence and outcome.

Improving the reporting of pragmatic trials: an extension of the CONSORT statement.

Abstract: Background The CONSORT statement is intended to improve reporting of randomised controlled trials and focuses on minimising the risk of bias (internal validity). The applicability of a trial’s results (generalisability or external validity) is also important, particularly for pragmatic trials. A pragmatic trial (a term first used in 1967 by Schwartz and Lellouch) can be broadly defined as a randomised controlled trial whose purpose is to inform decisions about practice. This extension of the CONSORT statement is intended to improve the reporting of such trials and focuses on applicability. Methods At two, two-day meetings held in Toronto in 2005 and 2008, we reviewed the CONSORT statement and its extensions, the literature on pragmatic trials and applicability, and our experiences in conducting pragmatic trials. Recommendations We recommend extending eight CONSORT checklist items for reporting of pragmatic trials: the background, participants, interventions, outcomes, sample size, blinding, participant flow, and generalisability of the findings. These extensions are presented, along with illustrative examples of reporting, and an explanation of each extension. Adherence to these reporting criteria will make it easier for decision makers to judge how applicable the results of randomised controlled trials are to their own conditions. Empirical studies are needed to ascertain the usefulness and comprehensiveness of these CONSORT checklist item extensions. In the meantime we recommend that those who support, conduct, and report pragmatic trials should use this extension of the CONSORT statement to facilitate the use of trial results in decisions about health care.

Living well: a self-determination theory perspective on eudaimonia

Abstract: This article distinguishes between hedonic and eudaimonic approaches to wellness, with the former focusing on the outcome of happiness or pleasure and the latter focusing not so much on outcomes as on the process of living well. We present a model of eudaimonia that is based in self-determination theory, arguing that eudaimonic living can be characterized in terms of four motivational concepts: (1) pursuing intrinsic goals and values for their own sake, including personal growth, relationships, community, and health, rather than extrinsic goals and values, such as wealth, fame, image, and power; (2) behaving in autonomous, volitional, or consensual ways, rather than heteronomous or controlled ways; (3) being mindful and acting with a sense of awareness; and (4) behaving in ways that satisfy basic psychological needs for competence, relatedness, and autonomy. In fact, we theorize that the first three of these aspects of eudaimonic living have their positive effects of psychological and physical wellness because they facilitate satisfaction of these basic, universal psychological needs. Studies indicate that people high in eudaimonic living tend to behave in more prosocial ways, thus benefiting the collective as well as themselves, and that conditions both within the family and in society more generally contribute toward strengthening versus diminishing the degree to which people live eudaimonic lives.

Vasopressin versus Norepinephrine Infusion in Patients with Septic Shock

Abstract: Background Vasopressin is commonly used as an adjunct to catecholamines to support blood pressure in refractory septic shock, but its effect on mortality is unknown. We hypothesized that low-dose vasopressin as compared with norepinephrine would decrease mortality among patients with septic shock who were being treated with conventional (catecholamine) vasopressors. Methods In this multicenter, randomized, double-blind trial, we assigned patients who had septic shock and were receiving a minimum of 5 μg of norepinephrine per minute to receive either low-dose vasopressin (0.01 to 0.03 U per minute) or norepinephrine (5 to 15 μg per minute) in addition to open-label vasopressors. All vasopressor infusions were titrated and tapered according to protocols to maintain a target blood pressure. The primary end point was the mortality rate 28 days after the start of infusions. Results A total of 778 patients underwent randomization, were infused with the study drug (396 patients received vasopressin, and 382 norepinephrine), and were included in the analysis. There was no significant difference between the vasopressin and norepinephrine groups in the 28-day mortality rate (35.4% and 39.3%, respectively; P = 0.26) or in 90-day mortality (43.9% and 49.6%, respectively; P = 0.11). There were no significant differences in the overall rates of serious adverse events (10.3% and 10.5%, respectively; P = 1.00). In the prospectively defined stratum of less severe septic shock, the mortality rate was lower in the vasopressin group than in the norepinephrine group at 28 days (26.5% vs. 35.7%, P = 0.05); in the stratum of more severe septic shock, there was no significant difference in 28-day mortality (44.0% and 42.5%, respectively; P = 0.76). A test for heterogeneity between these two study strata was not significant (P = 0.10). Conclusions Low-dose vasopressin did not reduce mortality rates as compared with norepinephrine among patients with septic shock who were treated with catecholamine vasopressors. (Current Controlled Trials number, ISRCTN94845869.)

Ventilation Strategy Using Low Tidal Volumes, Recruitment Maneuvers, and High Positive End-Expiratory Pressure for Acute Lung Injury and Acute Respiratory Distress Syndrome A Randomized Controlled Trial

Abstract: Context Low-tidal-volume ventilation reduces mortality in critically ill patients with acute lung injury and acute respiratory distress syndrome. Instituting additional strategies to open collapsed lung tissue may further reduce mortality. Objective To compare an established low-tidal-volume ventilation strategy with an experimental strategy based on the original “open-lung approach,” combining low tidal volume, lung recruitment maneuvers, and high positive-end–expiratory pressure. Design and Setting Randomized controlled trial with concealed allocation and blinded data analysis conducted between August 2000 and March 2006 in 30 intensive care units in Canada, Australia, and Saudi Arabia. Patients Nine hundred eighty-three consecutive patients with acute lung injury and a ratio of arterial oxygen tension to inspired oxygen fraction not exceeding 250. Interventions The control strategy included target tidal volumes of 6 mL/kg of predicted body weight, plateau airway pressures not exceeding 30 cm H 2 O, and conventional levels of positive end-expiratory pressure (n = 508). The experimental strategy included target tidal volumes of 6 mL/kg of predicted body weight, plateau pressures not exceeding 40 cm H 2 O, recruitment maneuvers, and higher positive end-expiratory pressures (n = 475). Main Outcome Measure All-cause hospital mortality. Results Eighty-five percent of the 983 study patients met criteria for acute respiratory distress syndrome at enrollment. Tidal volumes remained similar in the 2 groups, and mean positive end-expiratory pressures were 14.6 (SD, 3.4) cm H 2 O in the experimental group vs 9.8 (SD, 2.7) cm H 2 O among controls during the first 72 hours (P < .001). All-cause hospital mortality rates were 36.4% and 40.4%, respectively (relative risk [RR], 0.90; 95% confidence interval [CI], 0.77-1.05; P = .19). Barotrauma rates were 11.2% and 9.1% (RR, 1.21; 95% CI, 0.83-1.75; P = .33). The experimental group had lower rates of refractory hypoxemia (4.6% vs 10.2%; RR, 0.54; 95% CI, 0.34-0.86; P = .01), death with refractory hypoxemia (4.2% vs 8.9%; RR, 0.56; 95% CI, 0.34-0.93; P = .03), and previously defined eligible use of rescue therapies (5.1% vs 9.3%; RR, 0.61; 95% CI, 0.38-0.99; P = .045). Conclusions For patients with acute lung injury and acute respiratory distress syndrome, a multifaceted protocolized ventilation strategy designed to recruit and open the lung resulted in no significant difference in all-cause hospital mortality or barotrauma compared with an established low-tidal-volume protocolized ventilation strategy. This “open-lung” strategy did appear to improve secondary end points related to hypoxemia and use of rescue therapies. Trial Registration clinicaltrials.gov Identifier: NCT00182195

CO2 bio-mitigation using microalgae

Abstract: Microalgae are a group of unicellular or simple multicellular photosynthetic microorganisms that can fix CO2 efficiently from different sources, including the atmosphere, industrial exhaust gases, and soluble carbonate salts. Combination of CO2 fixation, biofuel production, and wastewater treatment may provide a very promising alternative to current CO2 mitigation strategies.

Effects of nitrogen sources on cell growth and lipid accumulation of green alga Neochloris oleoabundans

Abstract: Microalgal lipids are the oils of future for sustainable biodiesel production. However, relatively high production costs due to low lipid productivity have been one of the major obstacles impeding their commercial production. We studied the effects of nitrogen sources and their concentrations on cell growth and lipid accumulation of Neochloris oleoabundans, one of the most promising oil-rich microalgal species. While the highest lipid cell content of 0.40 g/g was obtained at the lowest sodium nitrate concentration (3 mM), a remarkable lipid productivity of 0.133 g l−1 day−1 was achieved at 5 mM with a lipid cell content of 0.34 g/g and a biomass productivity of 0.40 g l−1 day−1. The highest biomass productivity was obtained at 10 mM sodium nitrate, with a biomass concentration of 3.2 g/l and a biomass productivity of 0.63 g l−1 day−1. It was observed that cell growth continued after the exhaustion of external nitrogen pool, hypothetically supported by the consumption of intracellular nitrogen pools such as chlorophyll molecules. The relationship among nitrate depletion, cell growth, lipid cell content, and cell chlorophyll content are discussed.

Biofuels from microalgae.

Abstract: Microalgae are a diverse group of prokaryotic and eukaryotic photosynthetic microorganisms that grow rapidly due to their simple structure. They can potentially be employed for the production of biofuels in an economically effective and environmentally sustainable manner. Microalgae have been investigated for the production of a number of different biofuels including biodiesel, bio-oil, bio-syngas, and bio-hydrogen. The production of these biofuels can be coupled with flue gas CO2 mitigation, wastewater treatment, and the production of high-value chemicals. Microalgal farming can also be carried out with seawater using marine microalgal species as the producers. Developments in microalgal cultivation and downstream processing (e.g., harvesting, drying, and thermochemical processing) are expected to further enhance the cost-effectiveness of the biofuel from microalgae strategy.

Adaptive co-management and the paradox of learning

Abstract: Much emphasis has been placed on the importance of learning to support collaborative environmental management and achieve sustainability under conditions of social–ecological change. Yet, on-going struggles to learn from experience and respond to complex social–ecological conditions reflect an emerging paradox. Despite widespread support of learning as a normative goal and process, core concepts, assumptions and approaches to learning have been applied in vague and sometimes uncritical ways. Greater specificity with respect to learning goals, approaches and outcomes is required. In response to this gap, we examine five dimensions of the learning paradox in the context of adaptive co-management, where the learning and linking functions of governance are stressed: (i) definitions of learning; (ii) learning goals and expectations; (iii) mechanisms by which learning takes place; (iv) questions regarding who is involved in the process of learning; and (v) the risks and ethical ambiguities faced by different actors expected to willingly participate in a learning process, whether formal or informal. Lessons from experience with a series of cases from the global North and South illustrate the implications of these dimensions. Resolving the dimensions of this learning paradox will require greater attention to capacity-building, recognition of the role of risk, and consideration of how incentives could be used to encourage learning. Further consideration of the role of power and marginality among groups participating in the learning process is also needed, as is more systematic evaluation to monitor and measure learning outcomes.

Healthcare professionals' intentions and behaviours: A systematic review of studies based on social cognitive theories

Abstract: There is an important gap between the implications of clinical research evidence and the routine clinical practice of healthcare professionals. Because individual decisions are often central to adoption of a clinical-related behaviour, more information about the cognitive mechanisms underlying behaviours is needed to improve behaviour change interventions targeting healthcare professionals. The aim of this study was to systematically review the published scientific literature about factors influencing health professionals' behaviours based on social cognitive theories. These theories refer to theories where individual cognitions/thoughts are viewed as processes intervening between observable stimuli and responses in real world situations. We searched psycINFO, MEDLINE, EMBASE, CIHNAL, Index to theses, PROQUEST dissertations and theses and Current Contents for articles published in English only. We included studies that aimed to predict healthcare professionals' intentions and behaviours with a clear specification of relying on a social cognitive theory. Information on percent of explained variance (R2) was used to compute the overall frequency-weighted mean R2 to evaluate the efficacy of prediction in several contexts and according to different methodological aspects. The cognitive factors most consistently associated with prediction of healthcare professionals' intention and behaviours were documented. Seventy eight studies met the inclusion criteria. Among these studies, 72 provided information on the determinants of intention and 16 prospective studies provided information on the determinants of behaviour. The theory most often used as reference was the Theory of Reasoned Action (TRA) or its extension the Theory of Planned Behaviour (TPB). An overall frequency-weighted mean R2 of 0.31 was observed for the prediction of behaviour; 0.59 for the prediction of intention. A number of moderators influenced the efficacy of prediction; frequency-weighted mean R2 varied from 0.001 to 0.58 for behaviour and 0.19 to 0.81 for intention. Our results suggest that the TPB appears to be an appropriate theory to predict behaviour whereas other theories better capture the dynamic underlying intention. In addition, given the variations in efficacy of prediction, special care should be given to methodological issues, especially to better define the context of behaviour performance.

Fibrin: a versatile scaffold for tissue engineering applications.

Abstract: Tissue engineering combines cell and molecular biology with materials and mechanical engineering to replace damaged or diseased organs and tissues. Fibrin is a critical blood component responsible for hemostasis, which has been used extensively as a biopolymer scaffold in tissue engineering. In this review we summarize the latest developments in organ and tissue regeneration using fibrin as the scaffold material. Commercially available fibrinogen and thrombin are combined to form a fibrin hydrogel. The incorporation of bioactive peptides and growth factors via a heparin-binding delivery system improves the functionality of fibrin as a scaffold. New technologies such as inkjet printing and magnetically influenced self-assembly can alter the geometry of the fibrin structure into appropriate and predictable forms. Fibrin can be prepared from autologous plasma, and is available as glue or as engineered microbeads. Fibrin alone or in combination with other materials has been used as a biological scaffold for s...

The PINK1/Parkin pathway regulates mitochondrial morphology

Abstract: Loss-of-function mutations in the PTEN-induced kinase 1 (PINK1) or parkin genes, which encode a mitochondrially localized serine/threonine kinase and a ubiquitin-protein ligase, respectively, result in recessive familial forms of Parkinsonism. Genetic studies in Drosophila indicate that PINK1 acts upstream of Parkin in a common pathway that influences mitochondrial integrity in a subset of tissues, including flight muscle and dopaminergic neurons. The mechanism by which PINK1 and Parkin influence mitochondrial integrity is currently unknown, although mutations in the PINK1 and parkin genes result in enlarged or swollen mitochondria, suggesting a possible regulatory role for the PINK1/Parkin pathway in mitochondrial morphology. To address this hypothesis, we examined the influence of genetic alterations affecting the machinery that governs mitochondrial morphology on the PINK1 and parkin mutant phenotypes. We report that heterozygous loss-of-function mutations of drp1, which encodes a key mitochondrial fission-promoting component, are largely lethal in a PINK1 or parkin mutant background. Conversely, the flight muscle degeneration and mitochondrial morphological alterations that result from mutations in PINK1 and parkin are strongly suppressed by increased drp1 gene dosage and by heterozygous loss-of-function mutations affecting the mitochondrial fusion-promoting factors OPA1 and Mfn2. Finally, we find that an eye phenotype associated with increased PINK1/Parkin pathway activity is suppressed by perturbations that reduce mitochondrial fission and enhanced by perturbations that reduce mitochondrial fusion. Our studies suggest that the PINK1/Parkin pathway promotes mitochondrial fission and that the loss of mitochondrial and tissue integrity in PINK1 and parkin mutants derives from reduced mitochondrial fission.

Analysis of the Concerted Metalation-Deprotonation Mechanism in Palladium-Catalyzed Direct Arylation Across a Broad Range of Aromatic Substrates

Abstract: The concerted metalation−deprotonation mechanism predicts relative reactivity and regioselectivity for a diverse set of arenes spanning the entire spectrum of known palladium-catalyzed direct arylation coupling partners. An analysis following an active strain model provides a more complete portrayal of the important arene/catalyst parameters leading to a successful coupling. The breadth of arenes whose reactivity can be predicted by the CMD mechanism indicates that it may be far more widespread than previously imagined.

The Declaration of Helsinki and public health

Abstract: Determining the optimal relationship between public health and individual health is a major ethical challenge for health systems and providers. In theory, there should be no conflict between the two – the public consists of individuals and public health can be considered as the sum of the health of all those individuals. However, the situation is not quite that simple. Conflicts do exist – over issues including funding, treatment, duties, rights and preferences. The focus of this paper is the conflict between individual and public health in the ethics of research on humans. I will use the World Medical Association (WMA)’s Declaration of Helsinki (DoH) to demonstrate that, while concern for the individual has predominated over the needs of public health since World War Two, in recent years there has been some movement towards redressing this imbalance. The DoH was first adopted at the 1964 WMA General Assembly in Helsinki. Its purpose was to provide guidance to physicians engaged in clinical research and its main focus was the responsibilities of researchers for the protection of research subjects. The advancement of medical science and the promotion of public health, although recognized as important objectives of medical research, were clearly subordinate to the well-being of individual research subjects. The reasons for this emphasis on protection of research subjects are not difficult to discern. The DoH, like its well-known predecessor, the Nuremberg Code, was intended to prevent mistreatment of research subjects such as had been practised by Nazi physicians. In the absence of external constraints like legal frameworks and research ethics committees, it placed the responsibility to protect research subjects on medical researchers, who at that time were mostly physicians. It drew heavily on traditional medical ethics, as summarized in documents such as the WMA Declaration of Geneva which requires of the physician that: “The health of my patient will be my first consideration.”1 In relation to the Nuremberg Code, however, the 1964 DoH represented a subtle shift in the balance between the responsibilities of the researcher to individual research participants and “to further scientific knowledge and to help suffering humanity”, i.e. for public health. This shift is most evident in the requirement to obtain the informed consent of participants. This requirement was absolute in the Nuremberg Code but was softened in the DoH to allow research on children, especially for vaccines, and on incompetent or ‘captive’ populations, such as prisoners and military personnel.2 Still, the 1964 DoH was composed mainly of restrictions on medical research designed to safeguard the interests of individual participants. The first revision of the DoH was adopted in 1975. In the wake of revelations that serious abuses of research ethics were relatively commonplace, the WMA made explicit what had only been implicit in the 1964 version that “In research on man, the interest of science and society should never take precedence over considerations related to the well-being of the subject” (paragraph III. 4, 1975 version). As important as the needs of public health may be, they must not override the rights of individuals who take part in medical research. Since it appeared that some researchers could not be trusted to protect research participants, new requirements were added to the DoH, including advance review of projects by an independent committee and adherence to the principles of the DoH as a condition for publication of the results of the research. Minor amendments to the DoH were adopted in 1983, 1989 and 1996.3 These did not alter the predominance of the individual research subject’s interests over those of society. In contrast, the version that was adopted at the 2000 WMA General Assembly represented a major revision and expansion of the document. Although the emphasis on the primacy of the individual was retained, the following amendments indicate an increased awareness of the needs of public health: The 2000 version did away with the distinction between ‘therapeutic’ and ‘non-therapeutic’ research that had been a hallmark of the DoH since 1964. This distinction was based on the premise that much medical research is therapeutic, i.e. is intended to benefit the research subject: “The physician can combine medical research with professional care, the objective being the acquisition of new medical knowledge, only to the extent that medical research is justified by its potential diagnostic or therapeutic value for the patient” (paragraph II. 6, 1996 version). In contrast, the purpose of research in the 2000 version is the advancement of knowledge for the benefit of future patients; double-blinded clinical trials clearly demonstrate this purpose and its limitations for the health needs of research subjects. The 2000 version introduced an entirely new concept – the responsibility of researchers and sponsors to provide benefits to populations: “Medical research is only justified if there is a reasonable likelihood that the populations in which the research is carried out stand to benefit from the results of the research” (paragraph 19). Although the nature and extent of these benefits is not specified, the amendment clearly adds a significant public-health component to research ethics. In May 2007 the WMA Council authorized a new review of the DoH.4 A call for suggested amendments was distributed widely during 2007; the responses were collated and presented to the WMA Medical Ethics Committee in October 2007. Following that meeting a set of draft amendments was prepared by a working group and distributed for comment. A revised draft was considered by the Medical Ethics Committee in May 2008 and another consultation took place during the summer. The working group’s final recommendations will be considered at the 2008 WMA General Assembly. Although it will be up to the General Assembly to decide what, if any, changes will be made to the DoH, the working group’s draft amendments suggest a continuation of the trend, noted in the 2000 version, towards a greater concern for public-health, as follows: Specific mention is made of epidemiological research, which by its nature aims at the improvement of public health and health systems rather than the health of individual research subjects. Another suggested amendment calls for appropriate access to participation in research for populations that have previously been underrepresented, such as children and pregnant women. The statement on risks and burdens is expanded to include their application to the communities as well as to the individuals involved in the research. However, the statement that “considerations related to the well-being of the human subject should take precedence over the interests of science and society” is essentially unchanged.

NADPH oxidases, reactive oxygen species, and hypertension: clinical implications and therapeutic possibilities.

Abstract: Reactive oxygen species (ROS) influence many physiological processes including host defense, hormone biosynthesis, fertilization, and cellular signaling. Increased ROS production (termed "oxidative stress") has been implicated in various pathologies, including hypertension, atherosclerosis, diabetes, and chronic kidney disease. A major source for vascular and renal ROS is a family of nonphagocytic NAD(P)H oxidases, including the prototypic Nox2 homolog-based NAD(P)H oxidase, as well as other NAD(P)H oxidases, such as Nox1 and Nox4. Other possible sources include mitochondrial electron transport enzymes, xanthine oxidase, cyclooxygenase, lipoxygenase, and uncoupled nitric oxide synthase. NAD(P)H oxidase-derived ROS plays a physiological role in the regulation of endothelial function and vascular tone and a pathophysiological role in endothelial dysfunction, inflammation, hypertrophy, apoptosis, migration, fibrosis, angiogenesis, and rarefaction, important processes underlying cardiovascular and renal remodeling in hypertension and diabetes. These findings have evoked considerable interest because of the possibilities that therapies against nonphagocytic NAD(P)H oxidase to decrease ROS generation and/or strategies to increase nitric oxide (NO) availability and antioxidants may be useful in minimizing vascular injury and renal dysfunction and thereby prevent or regress target organ damage associated with hypertension and diabetes. Here we highlight current developments in the field of reactive oxygen species and cardiovascular disease, focusing specifically on the recently identified novel Nox family of NAD(P)H oxidases in hypertension. We also discuss the potential role of targeting ROS as a therapeutic possibility in the management of hypertension and cardiovascular disease.

Indole Synthesis via Rhodium Catalyzed Oxidative Coupling of Acetanilides and Internal Alkynes

Abstract: The oxidative synthesis of highly functionalized indoles from simple anilines and internal alkynes mediated by a rhodium(III) catalyst is described. Good yields are obtained for a variety of aniline substrates, and good regioselectivity is obtained for the more sterically accessible position when meta-substituted anilines are used. Symmetrical and unsymmetrical alkynes react efficiently with high (>40:1) C2/C3 regioselectivity when aryl/alkyl substituted alkynes are used.

Genome-wide association scan identifies a colorectal cancer susceptibility locus on 11q23 and replicates risk loci at 8q24 and 18q21.

Abstract: In a genome-wide association study to identify loci associated with colorectal cancer (CRC) risk, we genotyped 555,510 SNPs in 1,012 early-onset Scottish CRC cases and 1,012 controls (phase 1). In phase 2, we genotyped the 15,008 highest-ranked SNPs in 2,057 Scottish cases and 2,111 controls. We then genotyped the five highest-ranked SNPs from the joint phase 1 and 2 analysis in 14,500 cases and 13,294 controls from seven populations, and identified a previously unreported association, rs3802842 on 11q23 (OR = 1.1; P = 5.8 x 10(-10)), showing population differences in risk. We also replicated and fine-mapped associations at 8q24 (rs7014346; OR = 1.19; P = 8.6 x 10(-26)) and 18q21 (rs4939827; OR = 1.2; P = 7.8 x 10(-28)). Risk was greater for rectal than for colon cancer for rs3802842 (P < 0.008) and rs4939827 (P < 0.009). Carrying all six possible risk alleles yielded OR = 2.6 (95% CI = 1.75-3.89) for CRC. These findings extend our understanding of the role of common genetic variation in CRC etiology.

Testing for multigroup equivalence of a measuring instrument:A walk through the process

Abstract: This article presents an overview and application of the steps taken in testing for the equivalence of a measuring instrument across one or more groups. Following a basic description of, and rationale underlying these steps, the process is illustrated with data comprising response scores to four nonacademic subscales (Physical SC [Ability], Physical SC [Appearance], Social SC [Peers], and Social SC [Parents]) of the Self Description Questionnaire-I for Australian (N= 497) and Nigerian (N= 439) adolescents. All tests for validity and equivalence are based on the analysis of covariance structures within the framework of CFA models using the EQS 6 program. Prospective impediments to equivalence are suggested and additional caveats proposed in the special case where the groups under study represent different cultures.

Hypothermia Therapy after Traumatic Brain Injury in Children

Abstract: A total of 225 children were randomly assigned to the hypothermia group or the normothermia group; the mean temperatures achieved in the two groups were 33.1±1.2°C and 36.9±0.5°C, respectively. At 6 months, 31% of the patients in the hypothermia group, as compared with 22% of the patients in the normothermia group, had an unfavorable outcome (relative risk, 1.41; 95% confidence interval [CI], 0.89 to 2.22; P = 0.14). There were 23 deaths (21%) in the hypothermia group and 14 deaths (12%) in the normothermia group (relative risk, 1.40; 95% CI, 0.90 to 2.27; P = 0.06). There was more hypotension (P = 0.047) and more vasoactive agents were administered (P<0.001) in the hypothermia group during the rewarming period than in the normothermia group. Lengths of stay in the intensive care unit and in the hospital and other adverse events were similar in the two groups. Conclusions In children with severe traumatic brain injury, hypothermia therapy that is initiated within 8 hours after injury and continued for 24 hours does not improve the neurologic outcome and may increase mortality. (Current Controlled Trials number, ISRCTN77393684.)

Differential diagnosis of suspected multiple sclerosis: a consensus approach

Abstract: Background and objectivesDiagnosis of multiple sclerosis (MS) requires exclusion of diseases that could better explain the clinical and paraclinical findings A systematic process for exclusion of alternative diagnoses has not been defined An International Panel of MS experts developed consensus perspectives on MS differential diagnosisMethodsUsing available literature and consensus, we developed guidelines for MS differential diagnosis, focusing on exclusion of potential MS mimics, diagnosis of common initial isolated clinical syndromes, and differentiating between MS and non-MS idiopathic inflammatory demyelinating diseasesResultsWe present recommendations for 1) clinical and paraclinical red flags suggesting alternative diagnoses to MS; 2) more precise definition of “clinically isolated syndromes” (CIS), often the first presentations of MS or its alternatives; 3) algorithms for diagnosis of three common CISs related to MS in the optic nerves, brainstem, and spinal cord; and 4) a classification schem

CONSORT for Reporting Randomized Controlled Trials in Journal and Conference Abstracts: Explanation and Elaboration

Abstract: Background Clear, transparent, and sufficiently detailed abstracts of conferences and journal articles related to randomized controlled trials (RCTs) are important, because readers often base their assessment of a trial solely on information in the abstract Here, we extend the CONSORT (Consolidated Standards of Reporting Trials) Statement to develop a minimum list of essential items, which authors should consider when reporting the results of a RCT in any journal or conference abstract

Assessment of cumulative evidence on genetic associations: interim guidelines

Abstract: Established guidelines for causal inference in epidemiological studies may be inappropriate for genetic associations. A consensus process was used to develop guidance criteria for assessing cumulative epidemiologic evidence in genetic associations. A proposed semi-quantitative index assigns three levels for the amount of evidence, extent of replication, and protection from bias, and also generates a composite assessment of 'strong', 'moderate' or 'weak' epidemiological credibility. In addition, we discuss how additional input and guidance can be derived from biological data. Future empirical research and consensus development are needed to develop an integrated model for combining epidemiological and biological evidence in the rapidly evolving field of investigation of genetic factors.

Identifying unprovoked thromboembolism patients at low risk for recurrence who can discontinue anticoagulant therapy

Abstract: Background: Whether to continue oral anticoagulant therapy beyond 6 months after an “unprovoked” venous thromboembolism is controversial. We sought to determine clinical predictors to identify patients who are at low risk of recurrent venous thromboembolism who could safely discontinue oral anticoagulants. Methods: In a multicentre prospective cohort study, 646 participants with a first, unprovoked major venous thromboembolism were enrolled over a 4-year period. Of these, 600 participants completed a mean 18-month follow-up in September 2006. We collected data for 69 potential predictors of recurrent venous thromboembolism while patients were taking oral anticoagulation therapy (5–7 months after initiation). During follow-up after discontinuing oral anticoagulation therapy, all episodes of suspected recurrent venous thromboembolism were independently adjudicated. We performed a multivariable analysis of predictor variables ( p Results: We identified 91 confirmed episodes of recurrent venous thromboembolism during follow-up after discontinuing oral anticoagulation therapy (annual risk 9.3%, 95% CI 7.7%–11.3%). Men had a 13.7% (95% CI 10.8%–17.0%) annual risk. There was no combination of clinical predictors that satisfied our criteria for identifying a low-risk subgroup of men. Fifty-two percent of women had 0 or 1 of the following characteristics: hyperpigmentation, edema or redness of either leg; D-dimer ≥ 250 μg/L while taking warfarin; body mass index ≥ 30 kg/m 2 ; or age ≥ 65 years. These women had an annual risk of 1.6% (95% CI 0.3%–4.6%). Women who had 2 or more of these findings had an annual risk of 14.1% (95% CI 10.9%–17.3%). Interpretation: Women with 0 or 1 risk factor may safely discontinue oral anticoagulant therapy after 6 months of therapy following a first unprovoked venous thromboembolism. This criterion does not apply to men. (http://Clinicaltrials.gov trial register number NCT00261014)