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GST Primary GST Primary Best Strategies for Health Care Quality Im... Best Strategies for Health Care Quality Improvement - Diabetes Quality Improvement Strategies for Antibio... Kathryn McDonald, Stanford-UCSF Evidence-b... Systematic review assessing the effect of ... Quality Improvement Strategies for Antibiotics Management Kathryn McDonald, Stanford-UCSF Evidence-based Practice Center, 117 Encina Commons, Stanford, CA 94305-6019, Kathy.mcdonald@stanford.edu Systematic review assessing the effect of quality improvement strategies on appropriate prescribing of antibiotics and appropriate choice of antibiotics. Adherence Adherence Assistive Devices Assistive Devices Childhood Burn Hanson MacMillan Childhood Burn Hanson MacMillan CLSA_9 CLSA_9 Cyberabuse Cyberabuse Cognitive Behavioural Therapy for Violent ... This review included randomized trials abo... Cognitive Behavioural Therapy for Violent Men who Batter Their Partners This review included randomized trials about the effects of cognitive behavioral therapy on domestic violence. The intervention included programs based on the Duluth Model. The violence had to be committed by a male toward his female partner. The violence also had to be physical. The primary outcomes were new arrests and convictions, and new reports of violence. CABG vs PCI CABG vs PCI Quality Improvement Strategies for Prevent... Quality Improvement Strategies for Preventing Nosocomial Infections (Created 17-Feb-06) Quality Improvement Strategies for Asthma ... Quality Improvement Strategies for Asthma Control Erectile Dysfunction (Created 30-Jan-06) Erectile Dysfunction (Created 30-Jan-06) Inequality - Smoking Cessation to Reduce S... This review was the first part of a projec... Inequality - Smoking Cessation to Reduce Socio-Economic Differences This review was the first part of a project about inequality. It included randomized trials about the effect of smoking cessation interventions on reducing socio-economic differences. The studies had to report data either on persons with low socio-economic groups status or, preferably, on both low and high socio-economic groups. Diet and Physical Activity to Reduce Socio... This review was the second part in a proje... Diet and Physical Activity to Reduce Socio-Economic Differences This review was the second part in a project about inequality. It included randomized trials about the effect of interventions on reducing socio-economic differences in diet and physical activity. The studies had to report data either on persons with low socio-economic groups status or, preferably, on both low and high socio-economic groups. Workfare The data in SRS are not identical to the d... Workfare The data in SRS are not identical to the data in the published report. We used SRS only for an updated search. The review included randomized trials about the effect of welfare-to-work programs. Participants were welfare recipients. There were basically two types of programs. The educational type tried to build knowledge and skills in order to help the welfare recipients acquire jobs that could support them economically. The "work first" approach was more aimed at getting the participants quickly into a job. Exercise interventions for the management ... The objective of this systematic review wa... Exercise interventions for the management of frailty The objective of this systematic review was to examine the effectiveness of current exercise interventions on the management of frailty. A comprehensive search of Medline, Embase, Psycinfo, Cinahl, Scopus, Ageline, Eric, and SportDiscus databases was conducted and produced 1808 citations. So far we have completed 2 levels of “title and abstract” screening and we ended up with 262 articles. We have just started the full text screening. Eligibility criteria included original studies whose participants were identified as frail or prefrail with specific criteria and in which structured physical activity was included as at least one component of the intervention. Create a free account, build a dictionary with saved terms to re-use later! Public Domestic Violence - Using Cognitive Behavior Therapy Smoking Cessation to Reduce Socio-Economic Differences Diet and Physical Activity to Reduce Socio-Economic Differences Workfare Exercise Interventions for the Management of Frailty Search     Simple Advanced Refine (4 coded questions)  Any of these:   Exact Phrase: All of these: None of these: Author: Periodical: Projects: No restrictions   Libraries: Public   Select SRS Projects Show Saved Terms Select Library Show articles that do not have abstracts  Type of Article Clinical Trial Editorial Letter Meta-Analysis Practice Guideline Randomized Controlled Trial Review Addresses Bibliography Biography Case Reports Classical Article Clinical Conference Clinical Trial, Phase I Clinical Trial, Phase II Clinical Trial, Phase III Clinical Trial, Phase IV Comment Comparative Study Consensus Development Conference Consensus Development Conference, NIH Controlled Clinical Trial Corrected and Republished Article Dictionary Directory Duplicate Publication English Abstract Evaluation Studies Festschrift Government Publications Guideline Historical Article Interview In Vitro Journal Article Lectures Legal Cases Legislation Multicenter Study News Newspaper Article Overall Patient Education Handout Periodical Index Published Erratum Retracted Publication Research Support, N.I.H., Extramural Research Support, N.I.H., Intramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 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Retraction of Publication Scientific Integrity Review Support of Research Technical Report Twin Study Validation Studies Not a Primary Study or Review Unknown Primary Study Case Series Case Control Cohort Study Observational Study Qualitative Research CBA or ITS Registry Double Blind Controlled before after study Quasi-randomized trial Simple before after study Cluster-RCT Non-Randomized Study Report Book Book chapter Dissertation Conference procedings Secondary Research Not RCT Humans or Animals Humans Animals Ages All Infant: birth-23 months All Child: 0-18 years All Adult: 19+ years Newborn: birth-1 month Infant: 1-23 months Preschool Child: 2-5 years Child: 6-12 years Adolescent: 13-18 years Adult: 19-44 years Middle Aged: 45-64 years Middle Aged + Aged: 45+ years Aged: 65+ years 80 and over: 80+ years Undetermined Language English French German Italian Japanese Russian Spanish Afrikaans Albanian Unknown Arabic Armenian Azerbaijani Bosnian Bulgarian Catalan Chinese Croatian Czech Danish Dutch Esperanto Estonian Finnish Georgian Greek, Modern Hebrew Hindi Hungarian Icelandic Indonesian Kinyarwanda Korean Latin Latvian Lithuanian Macedonian Malay Malayalam Maori Multiple Languages Norwegian Persian Polish Portuguese Pushto Romanian Sanskrit Scottish gaelic Serbian Slovak Slovenian Swedish Thai Turkish Ukrainian Vietnamese Not English Not French Results(1-25 of 115) Sort By: Publication Date Relevance Took: 0.294 seconds to search 17,750,454  Action: Copy Results to new Clipboard Build Search Link Page 1 of 5 1 2 3 4 > Last >> (115 articles found) Transmembrane nitration of hydrophobic tyrosyl peptides. Localization, characterization, mechanism of nitration, and biological implications. Mar 14, 2003 Hao Zhang,Kalpana Bhargava,Agnes Keszler,Jimmy Feix,Neil Hogg,Joy Joseph,B Kalyanaraman We have shown previously that peroxynitrite-induced nitration of a hydrophobic tyrosyl probe is greater than that of tyrosine in the aqueous phase (Zhang, H., Joseph, J., Feix, J., Hogg, N., and Kalyanaraman, B. (2001) Biochemistry 40, 7675-7686). In this study, we have tested the hypothesis that t... ( view more )he extent of tyrosine nitration depends on the intramembrane location of tyrosyl probes and on the nitrating species. To this end, we have synthesized membrane spanning 23-mer containing a single tyrosyl residue at positions 4, 8, and 12. The location of the tyrosine residues in the phospholipid membrane was determined by fluorescence and electron spin resonance techniques. Nitration was initiated by slow infusion of peroxynitrite, co-generated superoxide and nitric oxide ((.)NO), or a myeloperoxidase/hydrogen peroxide/nitrite anion (MPO/H(2)O(2)/NO(2)(-)) system. Results indicate that with slow infusion of peroxynitrite, nitration of transmembrane tyrosyl peptides was much higher (10-fold or more) than tyrosine nitration in aqueous phase. Peroxynitrite-dependent nitration of tyrosyl-containing peptides increased with increasing depth of the tyrosyl residue in the bilayer. In contrast, MPO/H(2)O(2)/ NO(2)(-)-induced tyrosyl nitration decreased with increasing depth of tyrosyl residues in the membrane. Transmembrane nitrations of tyrosyl-containing peptides induced by both peroxynitrite and MPO/H(2)O(2)/NO(2)(-) were totally inhibited by (.)NO that was slowly released from spermine NONOate. Nitration of peptides in both systems was concentration-dependently inhibited by unsaturated fatty acid. Concomitantly, an increase in lipid oxidation was detected. A mechanism involving (.)NO(2) radical is proposed for peroxynitrite and MPO/H(2)O(2)/NO(2)(-)-dependent transmembrane nitration reactions. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Enhancement of merocyanine 540 uptake and photodynamic cell killing by salicylates. Jul 1, 1994 J B Feix,M S Anderson,B Kalyanaraman Salicylate and several structurally analogous compounds enhance merocyanine 540 (MC540)-photosensitized killing of leukemia cells (M. A. Anderson, B. Kalyanaraman, and J. B. Feix, Cancer Res., 53: 806-809, 1993). In this work, we show that salicylic acid enhances the binding of MC540 prior to illum... ( view more )ination, as well as the light-stimulated uptake of MC540 by target L1210 murine and K562 human leukemia cells. Acetylsalicylic acid, 2,3- and 2,5-dihydroxybenzoic acids, and sodium benzoate also enhance MC540 uptake. The irradiation dose responses for loss of cell survival and enhanced MC540 uptake are well correlated, both being shifted to earlier time points in the presence of salicylate. Salicylic acid also enhanced photodynamic cell killing of A549 lung carcinoma and NIH:OVCAR-3 ovarian carcinoma cells, two cell types which are relatively resistant to MC540-mediated photosensitization. Cellular uptake of the anionic, potential-sensitive oxonol dye, bis-(1,3-dibutylbarbituric acid)-trimethine oxonol, is also increased by salicylate in a dose-dependent fashion. In contrast, cellular uptake of the cationic cyanine dye, 3,3'-dihexyloxacarbocyanine, is unaffected by salicylate. These studies suggest that increased uptake of MC540 is the basis of salicylate enhancement and that changes in plasma membrane potentials may play a mechanistic role in the potentiation of MC540 binding and cell killing. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Methods and applications of site-directed spin labeling EPR spectroscopy. 2008 Candice S Klug,Jimmy B Feix Site-directed spin labeling (SDSL) electron paramagnetic resonance (EPR) spectroscopy has emerged as a well-established method that can provide specific information on the location and environment of an individual residue within large and complex protein structures. The SDSL technique involves intr... ( view more )oducing a cysteine residue at the site of interest and then covalently labeling with a sulfhydryl-specific spin label containing a stable free radical, which is used as the EPR-detectable probe. SDSL directly probes the local environment, structure, and proximity of individual residues, and is often greatly advantageous over techniques that give global information on protein structure and changes. SDSL can detect and follow changes in local structure due to intramolecular conformational changes or dynamic interactions with other proteins, peptides, or substrates. In addition, this technique can detect changes in distances between two sites and provide information on the depth of spin labels located within a membrane bilayer. EPR is neither limited by the size of the protein or peptide nor limited by the optical properties of the sample and has the unique ability to address and answer structure and dynamics questions that are not solvable solely by genetic or crystal structure analysis, making it highly complementary to other structural methods. In this chapter, we introduce the basic methods for using SDSL EPR spectroscopy in the study of the structure and dynamics of proteins and peptides and illustrate the practical applications of this method through specific examples in the literature. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Membrane insertion and bilayer perturbation by antimicrobial peptide CM15. Sep 1, 2007 Sara Pistolesi,Rebecca Pogni,Jimmy B Feix Antimicrobial peptides (AMPs) are an important component of innate immunity and have generated considerable interest as a potential new class of antibiotic. The biological activity of AMPs is strongly influenced by peptide-membrane interactions; however, for many of these peptides the molecular det... ( view more )ails of how they disrupt and/or translocate across target membranes are not known. CM15 is a linear, synthetic hybrid AMP composed of the first seven residues of the cecropin A and residues 2-9 of the bee venom peptide mellitin. Previous studies have shown that upon membrane binding CM15 folds into an alpha-helix with its helical axis aligned parallel to the bilayer surface and have implicated the formation of 2.2-3.8 nm pores in its bactericidal activity. Here we report site-directed spin labeling electron paramagnetic resonance studies examining the behavior of CM15 analogs labeled with a methanethiosulfonate spin label (MTSL) and a brominated MTSL as a function of increasing peptide concentration and utilize phospholipid-analog spin labels to assess the effects of CM15 binding and accumulation on the physical properties of membrane lipids. We find that as the concentration of membrane-bound CM15 is increased the N-terminal domain of the peptide becomes more deeply immersed in the lipid bilayer. Only minimal changes are observed in the rotational dynamics of membrane lipids, and changes in lipid dynamics are confined primarily to near the membrane surface. However, the accumulation of membrane-bound CM15 dramatically increases accessibility of lipid-analog spin labels to the polar relaxation agent, nickel (II) ethylenediaminediacetate, suggesting an increased permeability of the membrane to polar solutes. These results are discussed in relation to the molecular mechanism of membrane disruption by CM15. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Children do show negative priming: further evidence for early development of an intact selective control mechanism. Sep 2007 Christian Frings,Silke Feix,Ulrike Röthig,Charlotte Brüser,Miriam Junge Reactions to stimuli that were shortly before presented as distractors are usually slowed down; this phenomenon is known as negative priming. Negative priming is an accepted index for tapping into selective control mechanisms. Although this effect is well established for adults, it has been claimed... ( view more ) that children do not show negative priming. Recently, however, V. E. Pritchard and E. Neumann challenged this view and concluded that selective control mechanisms are already fully developed in young children. The authors of the present study analyzed differences between older studies, in which no negative priming had been observed, and the Pritchard and Neumann (2004) study. In sum, the present study yielded further evidence for an intact selective control mechanism in young children. The authors also linked this empirical finding to the broader literature on negative priming by a direct comparison with an adult sample. ( view less ) View Full Abstract View Article Details   Related Articles Optimization of wavelets for classification of movement-related cortical potentials generated by variation of force-related parameters. May 15, 2007 Dario Farina,Omar Feix do Nascimento,Marie-Françoise Lucas,Christian Doncarli The paper presents a novel pattern recognition approach for the classification of single-trial movement-related cortical potentials (MRCPs) generated by variations of force-related parameters during voluntary tasks. The feature space was built from the coefficients of a discrete dyadic wavelet tran... ( view more )sformation. Mother wavelet parameterization allowed the tuning of basis functions to project the signals. The mother wavelet was optimized to minimize the classification error estimated from the training set. Classification was performed with a support vector machine (SVM) approach with optimization of the width of a Gaussian kernel and of the regularization parameter. The efficacy of the optimization procedures was representatively shown on electroencephalographic recordings from two subjects who performed unilateral isometric plantar flexions at two target torques and two rates of torque development. The proposed classification method was tested on four pairs of classes corresponding to the change in only one of the two parameters of the task. Misclassification rate (test set) in the classification of 1-s EEG activity immediately before the onset of the tasks was reduced from 50.8+/-2.9% with worst wavelet and nearest representative classifier, to 40.2+/-7.3% with optimal wavelet and nearest representative classifier, and to 15.8+/-3.4% with optimal wavelet and SVM with optimization of the kernel and regularization parameter. The proposed pattern recognition method is promising for classification of MRCPs modulated by variations of force-related parameters. ( view less ) View Full Abstract View Article Details   Related Articles Modulation of human motor cortex excitability by the cholinesterase inhibitor rivastigmine. Mar 19, 2007 Berthold Langguth,Elena Bauer,Sebastian Feix,Michael Landgrebe,Harald Binder,Philipp Sand,Göran Hajak,Peter Eichhammer Acetylcholine exerts strong neuromodulating action at cortical and subcortical neurons and networks. Alterations of cortical excitability, induced by acute and repeated administration of the acetylcholinesterase inhibitor rivastigmine were investigated with transcranial magnetic stimulation in heal... ( view more )thy volunteers. It was found that rivastigmine had an overall significant effect on the stimulus-response curve with mean values suggesting an enhancement 1.5 and 3 h after a single loading dose of 3 mg rivastigmine and a reduction after 7 days of daily administration of 3 mg rivastigmine. Motor threshold, intracortical inhibition, intracortical facilitation, cortical silent period, M-wave, F-wave and peripheral silent period remained unaffected either by acute or repeated administration of rivastigmine. Our results demonstrate that effects of acetylcholine on motor cortex excitability in healthy subjects are reflected by alterations of the stimulus-response curve. The differential effect between acute and chronic administration of rivastigmine may reflect dynamic properties of different receptor subtypes. ( view less ) View Full Abstract View Article Details   Related Articles Intoxication and settled insanity: a finding of not guilty by reason of insanity. 2007 Jeff Feix,Greg Wolber This article presents a case of first-degree murder for which the defendant was acquitted as not guilty by reason of insanity, based on a defense involving the concept of "settled insanity." The literature on settled insanity is reviewed and discussed in the context of voluntary and involuntary int... ( view more )oxication. Statute and case law from those jurisdictions in which settled insanity is specifically allowed as an acceptable threshold condition for the insanity defense define the concept as a permanent condition resulting from substance abuse, rather than the effects of intoxication, no matter how severe. Also discussed are potential criteria for this defense, including evidence that psychotic symptoms thought to be responsible for the crime were, in some manner, separate and apart from symptoms caused solely by voluntary acute intoxication. Other factors that may assist evaluators in differentiating settled insanity from the effects of acute intoxication are presented. It is recommended that evaluators attempt to determine the timing of the onset of psychotic symptoms in relation to substance abuse, the persistence of such symptoms beyond detoxification, and whether ongoing psychiatric treatment is necessary to ameliorate the symptoms beyond intoxication. In the case described, psychotic symptoms persisted long after acute intoxication and beyond the time when drugs or alcohol were detected in the accused's body, requiring clinical intervention for psychosis. Also, before the crime, the defendant had exhibited significant psychological difficulty. The evaluating clinician must still determine, even when a threshold condition is considered to be present, whether statutory criteria for the insanity defense (for the jurisdiction in which the crime allegedly took place) are met. ( view less ) View Full Abstract View Article Details   Related Articles Peptide-membrane interactions and mechanisms of membrane destruction by amphipathic alpha-helical antimicrobial peptides. Sep 2006 Hiromi Sato,Jimmy B Feix Antimicrobial peptides (AMPs) have received considerable interest as a source of new antibiotics with the potential for treatment of multiple-drug resistant infections. An important class of AMPs is composed of linear, cationic peptides that form amphipathic alpha-helices. Among the most potent of ... ( view more )these are the cecropins and synthetic peptides that are hybrids of cecropin and the bee venom peptide, mellitin. Both cecropins and cecropin-mellitin hybrids exist in solution as unstructured monomers, folding into predominantly alpha-helical structures upon membrane binding with their long helical axis parallel to the bilayer surface. Studies using model membranes have shown that these peptides intercalate into the lipid bilayer just below the level of the phospholipid glycerol backbone in a location that requires expansion of the outer leaflet of the bilayer, and evidence from a variety of experimental approaches indicates that expansion and thinning of the bilayer are common characteristics during the early stages of antimicrobial peptide-membrane interactions. Subsequent disruption of the membrane permeability barrier may occur by a variety of mechanisms, leading ultimately to loss of cytoplasmic membrane integrity and cell death. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Afferent-mediated modulation of the soleus muscle activity during the stance phase of human walking. Sep 2006 Nazarena Mazzaro,Michael J Grey,Omar Feix do Nascimento,Thomas Sinkjaer The aim of this study was to investigate the contribution of proprioceptive feedback to the amplitude modulation of the soleus muscle activity during human walking. We have previously shown that slow-velocity, small-amplitude ankle dorsiflexion enhancements and reductions applied during the stance ... ( view more )phase of the step cycle generate, respectively, increments and decrements on the ongoing soleus activity. We have also shown that the increments in soleus activity are at least partially mediated by feedback from group Ia fibres. In the present study, we further investigated the afferent-mediated contribution from muscle group II afferents, cutaneous and proprioceptive afferents from the foot, and load-sensitive afferents to the soleus EMG. Slow-velocity, small-amplitude ankle trajectory modifications were combined with the pharmaceutical depression of group II polysynaptic pathways with tizanidine hydrochloride, anaesthetic blocking of sensory information from the foot with injections of lidocaine hydrochloride, and modulation of load feedback by increasing and decreasing the body load. The depression of the group II afferents significantly reduced the soleus response to the ankle trajectory modifications. Blocking sensory feedback from the foot did not have an effect on the soleus muscle activity. Changes in body load affected the ongoing soleus activity level; however, it did not affect the amplitude of the soleus EMG responses to the ankle trajectory modifications. These results suggest that the feedback from group II afferents, and possibly from load-sensitive afferents, contribute to the amplitude modulation of the soleus muscle activity during the stance phase of the step cycle. However, feedback from cutaneous afferents and instrinsic proprioceptive afferents from the foot does not seem to contribute to this muscle activation. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Identification of superoxide dismutase as a cofactor for the pseudomonas type III toxin, ExoU. Aug 29, 2006 Hiromi Sato,Jimmy B Feix,Dara W Frank Pseudomonas aeruginosa is an opportunistic pathogen that uses a type III secretion system and four effector proteins to avoid innate immune responses. ExoS, ExoT, ExoY, and ExoU all possess enzymatic activities that disrupt host cellular physiology and prevent bacterial clearance by host defense me... ( view more )chanisms. The specificity of these toxins for eukaryotic cells depends on the presence of substrate targets and eukaryotic cofactors responsible for effector activation. We used a combined biochemical and proteomic approach to identify Cu(2+), Zn(2+)-superoxide dismutase (SOD1) as a cofactor that activates the phospholipase activity of ExoU. Recombinant ExoU (rExoU) was activated in a dose-dependent manner by either bovine liver SOD1 or the yeast ortholog, Sod1p, but not by either Fe or Mn-containing SODs from E. coli or small molecule SOD mimetics. Inhibitor studies indicated that SOD enzymatic activity was not required for the activation of rExoU. The physical interaction between rExoU and SOD was demonstrated by capture techniques using either of the two proteins immobilized onto the solid phase. Identification of SOD as a cofactor allowed us to develop a new assay using a fluorescent substrate to measure the phospholipase activity of rExoU. The ability of SOD to act as a cytoplasmic cofactor stimulating ExoU phospholipase activity has significant implications for the biological activity of the toxin. Further elucidation of the structural mechanism of ExoU activation by this eukaryotic cofactor may provide a rational approach to the design of inhibitors that can diminish tissue damage during infection by ExoU-producing strains of P. aeruginosa. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Osmoprotection of bacterial cells from toxicity caused by antimicrobial hybrid peptide CM15. Aug 22, 2006 Hiromi Sato,Jimmy B Feix Antimicrobial peptides exist ubiquitously as a host defense system in a broad range of species, including insects, amphibians, and mammals. The binding of these peptides is followed by the disruption of cytoplasmic membranes, leading to bacterial cell death; however, the precise mechanism of membra... ( view more )ne destruction has remained controversial. In this study, we have examined the mechanism of action for the antimicrobial peptide, CM15 (KWKLFKKIGAVLKVL), a chimeric peptide of cecropin and mellitin. We find that the cytotoxicity of CM15 against either E. coli or Pseudomonas aeruginosa can be mitigated by the addition of sugar or poly(ethylene glycol) osmolytes to the extracellular media. The dependence of osmoprotection on solute size suggests the formation of pores with an effective diameter of 2.2-3.8 nm. In contrast, no osmoprotection was observed for cell killing by the cationic detergent dodecyltrimethylammonium bromide. Osmolytes also protected cells against the cytotoxicity of CM15 expressed intracellularly as a C-terminal extension of the carrier protein ketosteroid isomerase (KSI). Osmoprotection against the intracellularly produced peptide was also dependent on osmolyte size, in a manner that was in agreement with that observed for extracellularly added synthetic CM15. These data indicate that the formation of discrete pores in the cytoplasmic membrane is a key factor in the mechanism of bacterial killing by CM15. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles EEG based BCI-towards a better control. Brain-computer interface research at Aalborg University. Jun 2006 Kim Dremstrup Nielsen,Alvaro Fuentes Cabrera,Omar Feix do Nascimento This paper summarizes the brain-computer interface (BCI)-related research being conducted at Aalborg University. Namely, an online synchronized BCI system using steady-state visual evoked potentials, and investigations on cortical modulation of movement-related parameters are presented. View Full Abstract View Article Details View Coded Data Related Articles BCI Meeting 2005--workshop on signals and recording methods. Jun 2006 Jonathan R Wolpaw,Gerald E Loeb,Brendan Z Allison,Emanuel Donchin,Omar Feix do Nascimento,William J Heetderks,Femke Nijboer,William G Shain,James N Turner This paper describes the highlights of presentations and discussions during the Third International BCI Meeting in a workshop that evaluated potential brain-computer interface (BCI) signals and currently available recording methods. It defined the main potential user populations and their needs, ad... ( view more )dressed the relative advantages and disadvantages of noninvasive and implanted (i.e., invasive) methodologies, considered ethical issues, and focused on the challenges involved in translating BCI systems from the laboratory to widespread clinical use. The workshop stressed the critical importance of developing useful applications that establish the practical value of BCI technology. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Movement-related parameters modulate cortical activity during imaginary isometric plantar-flexions. May 2006 Omar Feix do Nascimento,Kim Dremstrup Nielsen,Michael Voigt A multitude of studies have demonstrated a clear activation of the motor cortex during imagination of various motor tasks; however, it is still unclear if movement-related parameters (movement direction, range of motion, speed, force level and rate of force development) specifically modulate cortic... ( view more )al activation as they do during the execution of actual motor tasks. Accordingly, this study examined whether the rate of torque development (RTD) and/or the torque amplitude modulates cortical potentials generated during imaginary motor tasks. Fifteen subjects imagined four different left-sided isometric plantar-flexion tasks, while EEG and EMG recordings were being performed. The averaged EEG activity was analyzed in terms of movement-related potentials (MRPs), consisting of readiness potential (RP), motor potential (MP) and movement-monitoring potential (MMP). It was demonstrated that RTD and torque amplitude indeed modulate cortical activity during imaginary motor tasks. Information concerning movement-related parameters for imaginary plantar-flexion tasks seems to be encoded in the supplementary motor area (SMA) and the primary motor cortex (M1). A comparison between MRPs of imaginary and actual motor tasks revealed that early MRPs were morphologically similar, but differed significantly in amplitude. One of the possible suggestions to explain such a difference may be an "abortion" of ongoing motor programs. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Influence of directional orientations during gait initiation and stepping on movement-related cortical potentials. Jun 3, 2005 Omar Feix do Nascimento,Kim Dremstrup Nielsen,Michael Voigt The influence of directional orientation on movement-related potentials (MRPs) during gait initiation and stepping has been investigated in the present study, as well as possible effects caused by the distinction between gait initiation and stepping. Accordingly, electroencephalographic (EEG), elec... ( view more )tromyographic (EMG) and kinetic recordings were conducted while eight subjects initiated gait and were stepping in three different directions (namely, forward, backward and lateral). Five different movement-related potentials were extracted from the EEG recordings and statistically analyzed. Movement parameters were extracted from kinetic recordings and statistically analyzed as well. Results indicated that variations in directional orientation of gait and stepping were associated to changes in MRPs, but the associations between movement parameters and MRPs were conditional to the kind of task performed. Gait tasks were mainly differentiated in early MRPs while stepping tasks were more differentiated in late MRPs, indicating that differences between gait initiation and stepping might be associated with different levels of preparation and execution. Apparently the changes found in the movement-related potentials were not simply caused by changes in the sensorial input due to perception of the spatial environment, but rather because of variations in the movement kinematics and kinetics. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Characterization of phospholipase activity of the Pseudomonas aeruginosa type III cytotoxin, ExoU. Feb 2005 Hiromi Sato,Jimmy B Feix,Cecilia J Hillard,Dara W Frank Recombinant ExoU (rExoU) and yeast extract were used to optimize an in vitro phospholipase assay as a basis for identifying the mechanism for enzyme activation and substrate specificity. Our results support a model in which a eukaryotic protein cofactor or complex facilitates the interaction of rEx... ( view more )oU with phospholipid substrates. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Relationship between plantar-flexor torque generation and the magnitude of the movement-related potentials. Jan 2005 Omar Feix do Nascimento,Kim Dremstrup Nielsen,Michael Voigt This study investigates whether rate of torque development (RTD) and/or torque amplitude are reflected in the movement-related potentials (MRPs) preceding and accompanying isometric activation of plantar flexor muscles. Subjects were asked to perform six different tasks involving the left ankle joi... ( view more )nt. The tasks consisted of voluntary isometric plantar flexions at three different RTDs (two fixed rates and a 'ballistic' task) ending at two different torque amplitudes. The main observations from the analysis of the MRPs were: 1) the readiness potentials (RP) demonstrated a statistically significant discrimination between low and high torque amplitudes; 2) the RP, the motor potentials (MP) and the movement-monitoring potentials (MMP) could be statistically differentiated among the different RTDs; and 3) in general the MRPs demonstrated an ipsilateral tendency in relation to the involved limb. The results indicate that RP is a suitable parameter for differentiation between levels of isometric plantar flexion torque and MP and MMP are sensitive to a differentiation between RTDs. The correlation between MRPs and motor tasks involving different rates of torque development and levels of torque suggests that MRPs may comprise a potential solution for programming of intended movements to be executed by systems based on neural rehabilitation technology. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles A rare cause of anemia due to intestinal tuberculosis in a renal transplant recipient. Aug 2004 S Kandutsch,A Feix,M Haas,M Häfner,G Sunder-Plassmann,A Soleiman A renal transplant recipient with stable allograft function presented with massive hemorrhagic diarrhea and severe anemia. No microbial infection could be found in stool cultures. Early colonoscopy showed severe colitis with ulceration. Histological samples confirmed granulomatous inflammation with... ( view more ) acid-resistant Ziehl-Neelson-positive microorganisms of mycobacterial type. Polymerase chain reaction (PCR) analysis of native mucosal biopsies specified the infectious organism as Mycobacterium tuberculosis complex. The patient responded well to antimycobacterial therapy and was still asymptomatic after 6 months with a stable graft function. Our case shows that tuberculosis can be a severe clinical problem in transplant recipients. Most of the patients with intestinal tuberculosis, reported to literature, were diagnosed post mortem or after explorative laparotomy and bowel resection. Thus, intestinal tuberculosis should be considered when a transplant recipient shows abdominal symptoms with no clear evidence of another infection. Proper diagnosis and treatment resulted in a beneficial outcome in our patient. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Methionine synthase reductase MTRR 66A > G has no effect on total homocysteine, folate, and Vitamin B12 concentrations in renal transplant patients. May 2004 Alexandra Feix,Wolfgang C Winkelmayer,Corinna Eberle,Gere Sunder-Plassmann,Manuela Födinger The association of variants of the gene encoding methionine synthase reductase (MTRR) with hyperhomocysteinemia, folate and Vitamin B(12) status in kidney graft recipients is unknown. We examined two mutations in MTRR in a cross-sectional study of 733 kidney graft recipients. The allele frequency o... ( view more )f MTRR 66G was 0.55. 369 patients (50.3%) were heterozygous and 219 patients (29.9%) were homozygous for the mutation. None of the patients showed the 997C > G mutation. The allelic variants of MTRR 66A > G showed no significant association with total homocysteine (tHcy) levels, both in univariate analyses, and in a multivariate model controlling for age, gender, body mass index, renal function, time since transplantation, underlying kidney disease, as well as the MTHFR 677C > T/1298A > C genotypes. Similarly, no significant associations between the MTRR 66A > Ggenotypes and plasma folate or Vitamin B(12) levels were found. In conclusion, MTRR 66A > G has no major effect on tHcy, folate, or Vitamin B(12) plasma concentrations in kidney graft recipients. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Cell movements controlled by the Notch signalling cascade during foregut development in Drosophila. Apr 2004 Bernhard Fuss,Frank Josten,Maritta Feix,Michael Hoch Notch signalling is an evolutionarily conserved cell interaction mechanism, the role of which in controlling cell fate choices has been studied extensively. Recent studies in both vertebrates and invertebrates revealed additional functions of Notch in proliferation and apoptotic events. We provide ... ( view more )evidence for an essential role of the Notch signalling pathway during morphogenetic cell movements required for the formation of the foregut-associated proventriculus organ in the Drosophila embryo. We demonstrate that the activation of the Notch receptor occurs in two rows of boundary cells in the proventriculus primordium. The boundary cells delimit a population of foregut epithelial cells that invaginate into the endodermal midgut layer during proventriculus morphogenesis. Notch receptor activation requires the expression of its ligand Delta in the invaginating cells and apical Notch receptor localisation in the boundary cells. We further show that the movement of the proventricular cells is dependent on the short stop gene that encodes the Drosophila plectin homolog of vertebrates and is a cytoskeletal linker protein of the spectraplakin superfamily. short stop is transcriptionally activated in response to the Notch signalling pathway in boundary cells and we demonstrate that the localisation of the Notch receptor and Notch signalling activity depend on short stop activity. Our results provide a novel link between the Notch signalling pathway and cytoskeletal reorganisation controlling cell movement during the development of foregut-associated organs. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Cooperation of JAK/STAT and Notch signaling in the Drosophila foregut. Mar 1, 2004 Frank Josten,Bernhard Fuss,Maritta Feix,Torsten Meissner,Michael Hoch Temporal and spatial regulation of morphogenesis is pivotal to the formation of organs from simple epithelial tubes. In a genetic screen for novel genes controlling cell movement during posterior foregut development, we have identified and molecularly characterized two alleles of the domeless gene ... ( view more )which encodes the Drosophila Janus kinase (JAK)/STAT receptor. We demonstrate that mutants for domeless or any other known component of the canonical JAK/STAT signaling pathway display a failure of coordinated cell movement during the development of the proventriculus, a multiply folded organ which is formed by stereotyped cell rearrangements in the posterior foregut. Whereas the JAK/STAT receptor is expressed in all proventricular precursor cells, expression of upd encoding its ligand and of STAT92E, the signal transducer of the pathway, is locally restricted to cells that invaginate during proventriculus development. We demonstrate by analyzing gene expression mediated by a model Notch response element and by studying the expression of the Notch target gene short stop, which encodes a cytoskeletal crosslinker protein, that JAK/STAT signaling is required for the activation of Notch-dependent gene expression in the foregut. Our results provide strong evidence that JAK/STAT and Notch signaling cooperate in the regulation of target genes that control epithelial morphogenesis in the foregut. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles An immunodominant epitope of myelin basic protein is an amphipathic alpha-helix. Feb 13, 2004 Ian R Bates,Jimmy B Feix,Joan M Boggs,George Harauz Myelin basic protein is a candidate autoantigen in multiple sclerosis. One of its dominant antigenic epitopes is segment Pro85 to Pro96 (human sequence numbering, corresponding to Pro82 to Pro93 in the mouse). There have been several, contradictory predictions of secondary structure in this region;... ( view more ) either beta-sheet, alpha-helix, random coil, or combinations thereof have all been proposed. In this paper, molecular dynamics and site-directed spin labeling in aqueous solution indicate that this segment forms a transient alpha-helix, which is stabilized in 30% trifluoroethanol. When bound to a myelin-like membrane surface, this antigenic segment exhibits a depth profile that is characteristic of an amphipathic alpha-helix, penetrating up to 12 A into the bilayer. The alpha-helix is tilted approximately 9 degrees, and the central lysine is in an ideal snorkeling position for side-chain interaction with the negatively charged phospholipid head groups. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Membrane binding, structure, and localization of cecropin-mellitin hybrid peptides: a site-directed spin-labeling study. Jan 2004 Kalpana Bhargava,Jimmy B Feix The interaction of antimicrobial peptides with membranes is a key factor in determining their biological activity. In this study we have synthesized a series of minimized cecropin-mellitin hybrid peptides each containing a single cysteine residue, modified the cysteine with the sulfhydryl-specific ... ( view more )methanethiosulfonate spin-label, and used electron paramagnetic resonance spectroscopy to measure membrane-binding affinities and determine the orientation and localization of peptides bound to membranes that mimic the bacterial cytoplasmic membrane. All of the peptides were unstructured in aqueous solution but underwent a significant conformational change upon membrane binding that diminished the rotational mobility of the attached spin-label. Apparent partition coefficients were similar for five of the six constructs examined, indicating that location of the spin-label had little effect on peptide binding as long as the attachment site was in the relatively hydrophobic C-terminal domain. Depth measurements based on accessibility of the spin-labeled sites to oxygen and nickel ethylenediaminediacetate indicated that at high lipid/peptide ratios these peptides form a single alpha-helix, with the helical axis aligned parallel to the bilayer surface and immersed approximately 5 A below the membrane-aqueous interface. Such a localization would provide exposure of charged/polar residues on the hydrophilic face of the amphipathic helix to the aqueous phase, and allow the nonpolar residues along the opposite face of the helix to remain immersed in the hydrophobic phase of the bilayer. These results are discussed with respect to the mechanism of membrane disruption by antimicrobial peptides. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles A validation of the test of memory malingering in a forensic psychiatric setting. Oct 2003 Michael Weinborn,Tamara Orr,Steven Paul Woods,Emily Conover,Jeffrey Feix The Test of Memory Malingering (TOMM) has not been adequately validated in a forensic psychiatric setting. Dissimulation of cognitive impairment, as assessed by the TOMM, was evaluated in a group of 25 forensic inpatients admitted for evaluation of Competency to Stand Trial (CST/MSO group), and hyp... ( view more )othesized to be at higher risk for feigning cognitive impairment. A comparison group of 36 patients, who were either civilly committed or adjudicated Not Guilty by Reason of Insanity (CIVIL/NGRI group), were hypothesized to be less likely to feign cognitive impairment. Groups were comparable in age, education, premorbid intelligence, and psychiatric symptom severity. Significantly more CST/MSO patients (36%) scored below a recommended TOMM cutoff score relative to CIVIL/NGRI patients (6%). Findings indicate excellent specificity and modest sensitivity, and generally support the validity of the TOMM in a forensic psychiatric population. The utility of different cutoff scores and need for multiple indicators of effort are discussed. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Page 1 of 5 1 2 3 4 > Last >> (115 articles found)

      
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