Selection Bias in a Study of Implantable Defibrillator Patients: The Role of Type D Personality

# The Author(s) 2010. This article is published with open access at Springerlink.com Background Selection bias constitutes a major issue in research using volunteers as study participants. Purpose We examined whether research in partners may affect participation rates of implantable cardioverterdefibrillator (ICD) patients with a Type D personality (joint presence of negative affectivity and social inhibition). Method Patients who underwent ICD implantation between May 2003 and November 2007, and who had a partner, were included (n=440). In September 2005, a substudy on partners of ICD patients was added (n=276 patients). Results The proportion Type D patients after the start of the partner substudy was significantly lower as compared to the proportion before this substudy (17.5 % versus 28.8%; p= 0.006). Patients who participated following the start of the partner substudy were less likely to have a Type D personality (OR=0.44; p=0.002), adjusting for possible confounders. In the partner substudy, nonparticipation was more prevalent among partners of Type D patients as compared to partners of non-Type D patients (20.4 % versus 10.1%; p=0.044). Partner nonparticipation was marginally significantly associated with Type D personality of the patient (OR=2.13; p=0.083), adjusting for confounders. Conclusions The addition of a partner substudy may be related to a decreased proportion of participants with a Type D personality. Nonparticipation was more prevalent among partners of Type D patients. These observations may influence results of studies, as Type Ds tend to be less healthy

Tumor Necrosis Factor-Alpha G308α Gene Polymorphism and Essential Hypertension: A Meta-Analysis Involving 2244 Participants

BACKGROUND: The tumor necrosis factor-alpha (TNFα) G308A gene polymorphism has been implicated in susceptibility to essential hypertension (EH), but study results are still controversial. OBJECTIVE AND METHODS: The present meta-analysis is performed to investigate the relationship between the TNFα G308A gene polymorphism and EH. Electronic databases were searched and seven separate studies on the association of the TNF α G308A gene polymorphism with EH were analyzed. The meta-analysis involved 1092 EH patients and 1152 controls. The pooled odds ratios (ORs) and their corresponding 95% confidence interval (CI) were calculated by a fixed or random effect model. RESULTS: A significant relationship between the TNFα G308A gene polymorphism and EH was found in an allelic genetic model (OR: 1.45, 95% CI: 1.17 to 1.80, P = 0.0008), a recessive genetic model (OR: 3.181, 95% CI: 1.204 to 8.408, P = 0.02), and a homozygote model (OR: 3.454, 95% CI: 1.286 to 9.278, P = 0.014). No significant association between them was detected in both a dominant genetic model (OR: 1.55, 95% CI: 0.99 to 2.42, P = 0.06) or a heterozygote genetic model (OR: 1.45, 95% CI: 0.90 to 2.33, P = 0.13). CONCLUSION: The TNFα G308A gene polymorphism is associated with EH susceptibility

A cluster randomized controlled trial aimed at implementation of local quality improvement collaboratives to improve prescribing and test ordering performance of general practitioners: Study Protocol

<p>Abstract</p> <p>Background</p> <p>The use of guidelines in general practice is not optimal. Although evidence-based methods to improve guideline adherence are available, variation in physician adherence to general practice guidelines remains relatively high. The objective for this study is to transfer a quality improvement strategy based on audit, feedback, educational materials, and peer group discussion moderated by local opinion leaders to the field. The research questions are: is the multifaceted strategy implemented on a large scale as planned?; what is the effect on general practitioners' (GPs) test ordering and prescribing behaviour?; and what are the costs of implementing the strategy?</p> <p>Methods</p> <p>In order to evaluate the effects, costs and feasibility of this new strategy we plan a multi-centre cluster randomized controlled trial (RCT) with a balanced incomplete block design. Local GP groups in the south of the Netherlands already taking part in pharmacotherapeutic audit meeting groups, will be recruited by regional health officers. Approximately 50 groups of GPs will be randomly allocated to two arms. These GPs will be offered two different balanced sets of clinical topics. Each GP within a group will receive comparative feedback on test ordering and prescribing performance. The feedback will be discussed in the group and working agreements will be created after discussion of the guidelines and barriers to change. The data for the feedback will be collected from existing and newly formed databases, both at baseline and after one year.</p> <p>Discussion</p> <p>We are not aware of published studies on successes and failures of attempts to transfer to the stakeholders in the field a multifaceted strategy aimed at GPs' test ordering and prescribing behaviour. This pragmatic study will focus on compatibility with existing infrastructure, while permitting a certain degree of adaptation to local needs and routines.</p> <p>Trial registration</p> <p>Nederlands Trial Register ISRCTN40008171</p

Aspergillus as a multi-purpose cell factory: current status and perspectives

Aspergilli have a long history in biotechnology as expression platforms for the production of food ingredients, pharmaceuticals and enzymes. The achievements made during the last years, however, have the potential to revolutionize Aspergillus biotechnology and to assure Aspergillus a dominant place among microbial cell factories. This mini-review will highlight most recent breakthroughs in fundamental and applied Aspergillus research with a focus on new molecular tools, techniques and products. New trends and concepts related to Aspergillus genomics and systems biology will be discussed as well as the challenges that have to be met to integrate omics data with metabolic engineering attempts

'HepCheck Dublin': An Intensified Hepatitis C Screening Programme in a Homeless Population Demonstrates the Need for Alternative Models of Care

Background: Hepatitis C virus (HCV) is one of the main causes of chronic liver disease worldwide. Prevalence of HCV in homeless populations ranges from 3.9% to 36.2%. The HepCheck study sought to investigate and establish the characterisation of HCV burden among individuals who attended an intensified screening programme for HCV in homeless services in Dublin, Ireland. Methods: The HepCheck study was conducted as part of a larger European wide initiative called HepCare Europe. The study consisted of three phases; 1) all subjects completed a short survey and were offered a rapid oral HCV test; 2) a convenience sample of HCV positive participants from phase 1 were selected to complete a survey on health and social risk factors and 3) subjects were tracked along the referral pathway to identify whether they were referred to a specialist clinic, attended the specialist clinic, were assessed for cirrhosis by transient elastography (Fibroscan) and were treated for HCV. Results: 597 individuals were offered HCV screening, 73% were male and 63% reported having had a previous HCV screening. We screened 538 (90%) of those offered screening, with 37% testing positive. Among those who tested positive, 112 (56%) were ‘new positives’ and 44% were ‘known positives’. Undiagnosed HCV was prevalent in 19% of the study sample. Active past 30-day drug use was common, along with attendance for drug treatment. Unstable accommodation was the most common barrier to attending specialist appointments and accessing treatment. Depression and anxiety, dental problems and respiratory conditions were common reported health problems. 46 subjects were referred to specialised services and two subjects completed HCV treatment. Conclusions: This study demonstrates that the current hospital-based model of care is inadequate in addressing the specific needs of a homeless population and emphasises the need for a community-based treatment approach. Findings are intended to inform HepCare Europe in their development of a community-based model of care in order to engage with homeless individuals with multiple co-morbidities including substance abuse, who are affected by or infected with HCV

Testing the effectiveness of a mindfulness-based intervention to reduce emotional distress in outpatients with diabetes (DiaMind): design of a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Approximately 20-40% of outpatients with diabetes experience elevated levels of emotional distress, varying from disease-specific distress to general symptoms of anxiety and depression. The patient's emotional well-being is related to other unfavorable outcomes, like reduced quality of life, sub-optimal self-care, impaired glycemic control, higher risk of complications, and increased mortality rates. The purpose of this study is to test the effectiveness of a new diabetes-specific, mindfulness-based psychological intervention. First, with regard to reducing emotional distress; second, with respect to improving quality of life, dispositional mindfulness, and self-esteem of patients with diabetes; third, with regard to self-care and clinical outcomes; finally, a potential effect modification by clinical and personality characteristics will be explored.</p> <p>Methods/Design</p> <p>The Diabetes and Mindfulness study (DiaMind) is a randomized controlled trial. Patients with diabetes with low levels of emotional well-being will be recruited from outpatient diabetes clinics. Eligible patients will be randomized to an intervention group or a wait-list control group. The intervention group will receive the mindfulness program immediately, while the control group will receive the program eight months later. The primary outcome is emotional distress (anxiety, stress, depressive symptoms), for which data will be collected at baseline, four weeks, post intervention, and after six months follow-up. In addition, self-report data will be collected on quality of life, dispositional mindfulness, self-esteem, self-care, and personality, while complications and glycemic control will be assessed from medical files and blood pressure will be measured. Group differences will be analyzed with repeated measures analysis of covariance.</p> <p>The study is supported by grants from the Dutch Diabetes Research Foundation and Tilburg University and has been approved by a medical ethics committee.</p> <p>Discussion</p> <p>It is hypothesized that emotional well-being, quality of life, dispositional mindfulness, self-esteem, self-care, and blood pressure will improve significantly more in the mindfulness group compared to the control group. Results of this study can contribute to a better care for patients with diabetes with lowered levels of emotional well-being. It is expected that the first results will become available in 2012.</p> <p>Trial registration</p> <p>Dutch Trial Register <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2145">NTR2145</a>.</p

Environmental-dependent proline accumulation in plants living on gypsum soils

[EN] Biosynthesis of proline¿or other compatible solutes¿is a conserved response of all organisms to different abiotic stress conditions leading to cellular dehydration. However, the biological relevance of this reaction for plant stress tolerance mechanisms remains largely unknown, since there are very few available data on proline levels in stress-tolerant plants under natural conditions. The aim of this work was to establish the relationship between proline levels and different environmental stress factors in plants living on gypsum soils. During the 2-year study (2009¿2010), soil parameters and climatic data were monitored, and proline contents were determined, in six successive samplings, in ten taxa present in selected experimental plots, three in a gypsum area and one in a semiarid zone, both located in the province of Valencia, in south-east Spain. Mean proline values varied significantly between species; however, seasonal variations within species were in many cases even wider, with the most extreme differences registered in Helianthemum syriacum (almost 30 lmol g-1 of DW in summer 2009, as compared to ca. 0.5 in spring, in one of the plots of the gypsum zone). Higher proline contents in plants were generally observed under lower soil humidity conditions, especially in the 2009 summer sampling preceded by a severe drought period. Our results clearly show a positive correlation between the degree of environmental stress and the proline level in most of the taxa included in this study, supporting a functional role of proline in stress tolerance mechanisms of plants adapted to gypsum. However, the main trigger of proline biosynthesis in this type of habitat, as in arid or semiarid zones, is water deficit, while the component of ¿salt stress¿ due to the presence of gypsum in the soil only plays a secondary role.This work has been supported by the Spanish Ministry of Science and Innovation (Project CGL2008-00438/BOS), with contribution from the European Regional Development Fund.Boscaiu, M.; Bautista Carrascosa, I.; Lidón Cerezuela, AL.; Llinares Palacios, JV.; Lull, C.; Donat-Torres, M.; Mayoral García-Berlanga, O.... (2013). Environmental-dependent proline accumulation in plants living on gypsum soils. Acta Physiologiae Plantarum. 35:2193-2204. https://doi.org/10.1007/s11738-013-1256-3S2193220435Alvarado JJ, Ruiz JM, López-Cantarero I, Molero J, Romero L (2000) Nitrogen metabolism in five plant species characteristic of gypsiferous soils. 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Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration