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Reverse
Terms modified by Reverse Selected AbstractsBaseline Characteristics of Patients Randomized in the Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE) StudyCONGESTIVE HEART FAILURE, Issue 2 2008Cecilia Linde MD The Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE) study is a randomized controlled trial currently assessing the safety and efficacy of cardiac resynchronization therapy in patients with asymptomatic left ventricular (LV) dysfunction with previous symptoms of mild heart failure. This paper describes the baseline characteristics of randomized patients; 610 patients with New York Heart Association (NYHA) class II (82.3%) heart failure or asymptomatic (NYHA class I) LV dysfunction with previous symptoms (17.7%) were randomized in 73 centers. The mean age was 62.5±11.0 years, the mean LV ejection fraction was 26.7%±7.0%, and the mean LV end-diastolic diameter was 66.9±8.9 mm. A total of 97% of patients were taking angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and 95.1% were taking ,-blockers, which were at the target dose in 35.1% of patients. Compared with previous randomized cardiac resynchronization therapy trials, REVERSE patients are on better pharmacologic treatment, are younger, and have a narrower QRS width despite similar LV dysfunction. [source] Laďcité in Reverse: Mono-Religious Democracies and the Issue of Religion in the Public SphereCONSTELLATIONS: AN INTERNATIONAL JOURNAL OF CRITICAL AND DEMOCRATIC THEORY, Issue 1 2010Nadia Urbinati First page of article [source] Contractile Reserve Assessed Using Dobutamine Echocardiography Predicts Left Ventricular Reverse Remodeling after Cardiac Resynchronization Therapy: Prospective Validation in Patients with Left Ventricular DyssynchronyECHOCARDIOGRAPHY, Issue 6 2010F.R.C.P.C., Mario Sénéchal M.D. Background: The presence of viable myocardium may predict response to cardiac resynchronization therapy (CRT). The aim of this study is to evaluate in patients with left ventricular (LV) dyssynchrony whether response to CRT is related to myocardial viability in the region of the pacing lead. Methods: Forty-nine consecutive patients with advanced heart failure, LV ejection fraction < 35%, QRS duration > 120 ms and intraventricular asynchronism , 50 ms were included. Dobutamine stress echocardiography was performed within the week before CRT implantation. Resting echocardiography was performed 6 months after CRT implantation. Viability in the region of LV pacing lead was defined as the presence of viability in two contiguous segments. Response to CRT was defined by evidence of reverse LV remodeling (,15% reduction in LV end-systolic volume). Results: Thirty-one patients (63%) were identified as responders at follow-up. The average of viable segments was 5.9 ± 2 in responders and 3.2 ± 3 in nonresponders (P = 0.0003). Viability in the region of the pacing lead had a sensitivity of 94%, a specificity of 67%, a positive predictive value of 83%, and a negative predictive value of 86% for the prediction of response to CRT. Conclusions: In patients with LV dyssynchrony, reverse remodeling after CRT requires viability in the region of the pacing lead. This simple method using echocardiography dobutamine for the evaluation of local viability (i.e., viability in two contiguous segments) may be useful to the clinician in choosing the best LV lead positioning. (Echocardiography 2010;27:668-676) [source] Reverse Flow in Left Coronary Artery as the Clue to Diagnosis of an Anomalous Origin of the Left Coronary into Pulmonary Artery in an Infant with Dilated CardiomyopathyECHOCARDIOGRAPHY, Issue 6 2008Rodrigo Estévez M.D. No abstract is available for this article. [source] "Reverse degradomics", monitoring of proteolytic trimming by multi-CE and confocal detection of fluorescent substrates and reaction productsELECTROPHORESIS, Issue 13 2009Helene Piccard Abstract A platform for profiling of multiple proteolytic activities acting on one specific substrate, based on the use of a 96-channel capillary DNA sequencer with CE-LIF of labeled substrate peptides and reaction products is introduced. The approach consists of synthesis of a substrate peptide of interest, fluorescent labeling of the substrate, either aminoterminally by chemical coupling, or carboxyterminally by transglutaminase reaction, proteolysis by a biological mixture of proteases in the absence or presence of protease inhibitors, multi-channel analysis of substrate and reaction products, and data collection and processing. Intact substrate and reaction products, even when varying by only one amino acid, can be relatively semi-quantified in a high-throughput manner, yielding information on proteases acting in complex biological mixtures and without prepurification. Monitoring, classification and inhibition of multiple proteolytic activities are demonstrated on a model substrate, the aminoterminus of the mouse granulocyte chemotactic protein-2. In view of extensive processing of chemokines into various natural forms with different specific biological activities, and of the fragmentary knowledge of processing proteases, examples of processing by neutrophil degranulate, tumor cell culture fluids and plasma are provided. An example of selection and comparison of inhibitory mAbs illustrates that the platform is suitable for inhibitor screening. Whereas classical degradomics technologies analyze the substrate repertoire of one specific protease, here the complementary concept, namely the study of all proteases acting, in a biological context, on one specific substrate, is developed and tuned to identify key proteases and protease inhibitors for the processing of any biological substrate of interest. [source] Salinity as a structuring factor for the composition and performance of bacterioplankton degrading riverine DOCFEMS MICROBIOLOGY ECOLOGY, Issue 2 2003Silke Langenheder Abstract The impact of salinity on the composition and functional performance (biomass production, growth efficiency and growth rates) of bacterial communities was investigated using batch cultures growing on dissolved organic carbon from a river draining into the Northern Baltic Sea. The cultures were adjusted to riverine or estuarine salinity levels and inoculated with bacteria from these two environments. Bacterial growth efficiencies differed in response to salinity and the origin of the inoculum. When salinity was adjusted to correspond to the salinity at the site where the inoculum was retrieved, growth efficiency was relatively high (11.5±2.6%). However, when bacteria were confronted with a shift in salinity, growth efficiency was lower (7.5±2.0%) and more of the utilized carbon was respired. In contrast, growth rates were higher when bacteria were exposed to a change in salinity. The composition of the bacterial communities developing in the batch cultures differed, as shown by 16S rDNA DGGE, depending on the origin of the inoculum and salinity. Reverse and direct DNA,DNA hybridization revealed salinity optima in the growth of specific bacterial strains as well as broader phylogenetic groups. Strains belonging to the ,- and ,- Proteobacteria, Actinobacteria and ,- Proteobacteria other than the genus Pseudomonas showed higher relative abundance under freshwater conditions, whereas strains of the genus Pseudomonas and the Cytophaga,Flavobacterium,Bacteroides group were favored by estuarine conditions. Generally, our results demonstrate functional changes associated with changes in community composition. We suggest that even moderate changes in salinity affect bacterial community composition, which subsequently leads to altered growth characteristics. [source] Novel Fabrication of Size-Tunable Silica Nanotubes Using a Reverse- Microemulsion-Mediated Sol,Gel Method ,ADVANCED MATERIALS, Issue 9-10 2004J. Jang Size-tunable silica nanotubes have been fabricated using a novel reverse-microemulsion-mediated sol,gel method (see Figure). This facile approach is adaptable to large-scale fabrication, and the diameter of silica nanotubes is tunable through the use of different apolar solvents. The photoluminescence spectrum of the nanotubes displays three emission bands, including a stable and strong blue light emission at 435 nm. [source] Influence on mass-selective ion ejection of the phase difference between the drive r.f. and the axial modulation potentialsJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 6 2005G. Dobson Abstract The phase difference between the drive r.f. and the axial modulation potential is known to influence significantly the mass shift, and all commercial ion trap mass spectrometers use a fixed value for this difference. However, although this important parameter is partly responsible for the good precision achievable today in most commercial ion traps, little discussion on the variation of the phase difference between the drive r.f. and the axial modulation potential has appeared in the literature. We present here an examination of the influence of a low-level axial modulation potential superimposed by capacitive coupling between the electrodes. Low-level axial modulation potentials are used for certain analytical scans such as reverse scan or slow scan speeds. Such low-level potentials help to prevent deterioration of mass resolution due to, for example, the dissociation of the ions during their resonant ejection from the ion trap. Reverse and forward scans are used to illustrate the mass shift and change in resolution, caused by a change in the phase difference between the drive r.f. potential applied to the ring electrode and the axial modulation potential applied on an end-cap electrode, in electrospray ionization mass spectra. Copyright © 2005 John Wiley & Sons, Ltd. [source] Recovery of transition metal complex by reverse flow adsorptionAICHE JOURNAL, Issue 1 2008Jeroen Dunnewijk Abstract Reverse flow adsorption (RFA) is a technique with a definite potential to prevent the leaching of a homogenous catalyst. In this work, we model an RFA-process for a continuous ideally stirred tank reactor with an adsorption bed upstream and another one downstream from the reactor. The model parameters concerning adsorption equilibrium and kinetics are taken from previous experimental studies on CoCl2 adsorption on polymer-bound trifenylfosfine. We use this model to study the concentration profiles of CoCl2 in the adsorption beds during consecutive adsorption,desorption cycles. The model calculations show that the concentration profile eventually reaches a fixed position after a number of adsorption,desorption cycles, even though internal mass transfer was a limiting factor. Hence, the transition metal is kept within the system boundaries, which is an essential requirement for the application of RFA. © 2007 American Institute of Chemical Engineers AIChE J, 2008 [source] A RAPID METHOD OF QUANTIFYING THE RESOLUTION LIMITS OF HEAT-FLOW ESTIMATES IN BASIN MODELSJOURNAL OF PETROLEUM GEOLOGY, Issue 2 2008A. Beha Deterministic forward models are commonly used to quantify the processes accompanying basin evolution. Here, we describe a workflow for the rapid calibration of palaeo heat-flow behaviour. The method determines the heat-flow history which best matches the observed data, such as vitrinite reflectance, which is used to indicate the thermal maturity of a sedimentary rock. A limiting factor in determining the heat-flow history is the ability of the algorithm used in the software for the maturity calculation to resolve information inherent in the measured data. Thermal maturation is controlled by the temperature gradient in the basin over time and is therefore greatly affected by maximum burial depth. Calibration, i.e. finding the thermal history model which best fits the observed data (e.g. vitrinite reflectance), can be a time-consuming exercise. To shorten this process, a simple pseudo-inverse model is used to convert the complex thermal behaviour obtained from a basin simulator into more simple behaviour, using a relatively simple equation. By comparing the calculated "simple" maturation trend with the observed data points using the suggested workflow, it becomes relatively straightforward to evaluate the range within which a best-fit model will be found. Reverse mapping from the simple model to the complex behaviour results in precise values for the heat-flow which can then be applied to the basin model. The goodness-of-fit between the modelled and observed data can be represented by the Mean Squared Residual (MSR) during the calibration process. This parameter shows the mean squared difference between all measured data and the respective predicted maturities. A minimum MSR value indicates the "best fit". Case studies are presented of two wells in the Horn Graben, Danish North Sea. In both wells calibrating the basin model using a constant heat-flow over time is not justified, and a more complex thermal history must be considered. The pseudo-inverse method was therefore applied iteratively to investigate more complex heat-flow histories. Neither in the observed maturity data nor in the recorded stratigraphy was there evidence for erosion which would have influenced the present-day thermal maturity pattern, and heat-flow and time were therefore the only variables investigated. The aim was to determine the simplest "best-fit" heat-flow history which could be resolved at the maximum resolution given by the measured maturity data. The conclusion was that basin models in which the predicted maturity of sedimentary rocks is calibrated solely against observed vitrinite reflectance data cannot provide information on the timing of anomalies in the heat-flow history. The pseudo inverse method, however, allowed the simplest heat-flow history that best fits the observed data to be found. [source] Preparation of gradient copolymers via ATRP using a simultaneous reverse and normal initiation process.JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2005Abstract Spontaneous gradient copolymers were prepared in both bulk and miniemulsion systems via Atom Transfer Radical Polymerization (ATRP) utilizing a Simultaneous Reverse and Normal Initiation (SR & NI) process. Both instantaneous and cumulative compositions were used to characterize the gradient copolymers. The gradient copolymers were obtained with an array of gradient compositions ranging from a subtle to strong variation in monomer distribution along the polymer backbones, depending on the ratio of comonomers initially added to the copolymerization system. The compositions of the gradient copolymer produced in miniemulsion systems were similar to those generated in bulk. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3616,3622, 2005 [source] Reverse flow facial artery as recipient vessel for perforator flapsMICROSURGERY, Issue 6 2009D.D.S., Frank Hölzle M.D., Ph.D. In perforator flaps, anastomosis between flap and recipient vessels in the neck area is often difficult due to small vessel diameter and short pedicle. The aim of this study was to investigate whether the retrograde flow of the distal, paramandibular part of the facial artery would provide sufficient pressure and size to perfuse perforator flaps. Before and after occlusion of the contralateral facial artery, retrograde and anterograde arterial pressure was measured on both sides of the facial artery in 50 patients. The values were compared with the mean systemic arterial pressure. Diameters of facial arteries in the paramandibular region and perforator flap vessels were evaluated by morphometry. Arterial pressure in the distal facial artery with retrograde flow was 76% of the systemic arterial pressure. The latter equaled approximately the anterograde arterial pressure in the proximal end of the facial artery. Mean arterial pressure of the facial arteries decreased after proximal occlusion of the contralateral facial artery, which was not significant (P = 0.09). Mean diameter of the distal facial arteries in the mandibular region was 1.6 mm (range 1.3,2.2 mm; standard deviation 0.3 mm; n = 50), that of the perforator flap arteries 1.3 mm (0.9,2.6 mm; 0.4 mm; n = 20). Facial arteries, based on reverse flow, successfully supported all 20 perforator flaps. Retrograde pulsatile flow in the distal facial artery sustains perforator flaps even if the contralateral facial artery is occluded. Proximity of the distal facial arteries to the defect compensates for short pedicles. Matching diameters of the arteries are ideal for end-to-end anastomosis. © 2009 Wiley-Liss, Inc. Microsurgery, 2009. [source] Correlation of Electrical and Mechanical Reverse Remodeling after Cardiac Resynchronization TherapyANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2009Swapna Kamireddy M.D. Background: Cardiac resynchronization therapy (CRT) improves clinical outcome in many patients with refractory heart failure (HF). This study examined whether CRT is associated with reverse electrical remodeling by surface electrocardiogram (ECG). Methods: Consecutive CRT recipients at the University of Pittsburgh Medical Center with >90 days of follow-up were included in this analysis. ECG data were abstracted from medical records. Subjects with a relative increase of ,15% in left ventricular ejection fraction (LVEF) after CRT were considered responders. Results: A total of 113 patients (age 69 ± 11 years, men 70%, white 92%) were followed for a mean duration of 407 ± 290 (92,1439) days. Overall, LVEF increased after CRT (29 ± 13% vs 24 ± 9%; P < 0.01) and 50% of patients were responders. The mean native QRS interval among responders was higher than in nonresponders (163 ± 32 ms vs 148 ± 29 ms; P < 0.01). More than 3 months after CRT, there was no change in the paced QRS duration compared to baseline. Paced QRS duration, however, decreased among responders and increased among nonresponders and was significantly different by response status (P < 0.001). There was a significant correlation between increase in LVEF and decrease in paced QRS width in the overall population (r =,0.3; P < 0.01). Conclusions: Among responders to CRT, the paced QRS width decreases significantly, whereas it increases among nonresponders. Given the paced nature of the QRS, the improved conduction probably reflects enhanced cell-to-cell coupling after CRT as opposed to improved conduction within the His-Purkinje system. These findings have significant implications as to the mechanisms of benefit from CRT. [source] Parameters of Coseismic Reverse- and Oblique-Slip Surface Ruptures of the 2008 Wenchuan Earthquake, Eastern Tibetan PlateauACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2009Xiwei XU Abstract: On May 12th, 2008, the Mw7.9 Wenchuan earthquake ruptured the Beichuan, Pengguan and Xiaoyudong faults simultaneously along the middle segment of the Longmenshan thrust belt at the eastern margin of the Tibetan plateau. Field investigations constrain the surface rupture pattern, length and offsets related to the Wenchuan earthquake. The Beichuan fault has a NE-trending right-lateral reverse rupture with a total length of 240 km. Reassessment yields a maximum vertical offset of 6.5 ± 0.5 m and a maximum right-lateral offset of 4.9 ± 0.5 m for its northern segment, which are the largest offsets found; the maximum vertical offset is 6.2 ± 0.5 m for its southern segment. The Pengguan fault has a NE-trending pure reverse rupture about 72 km long with a maximum vertical offset of about 3.5 m. The Xiaoyudong fault has a NW-striking left-lateral reverse rupture about 7 km long between the Beichuan and Pengguan faults, with a maximum vertical offset of 3.4 m and left-lateral offset of 3.5 m. This pattern of multiple co-seismic surface ruptures is among the most complicated of recent great earthquakes and presents a much larger danger than if they ruptured individually. The rupture length is the longest for reverse faulting events ever reported. [source] Ascorbate Inhibits Reduced Arteriolar Conducted Vasoconstriction in Septic Mouse Cremaster MuscleMICROCIRCULATION, Issue 7 2007REBECCA L. MCKINNON ABSTRACT Objective: The mechanism of neuronal nitric oxide synthase (nNOS)-dependent reduction in arteriolar conducted vasoconstriction in sepsis, and the possible protection by antioxidants, are unknown. The authors hypothesized that ascorbate inhibits the conduction deficit by reducing nNOS-derived NO production. Methods: Using intravital microscopy and the cecal ligation and perforation (CLP) model of sepsis (24 h), arterioles in the cremaster muscle of male C57BL/6 wild-type mice were locally stimulated with KCl to initiate conducted vasoconstriction. The authors used the ratio of conducted constriction (500 , m upstream) to local constriction as an index of conduction (CR500). Cremaster muscle NOS enzymatic activity and protein expression, and plasma nitrite/nitrate levels were determined in control and septic mice. Intravenous ascorbate bolus (200 mg/kg in 0.1 ml of saline) was given early (0 h) or delayed at 23 h post CLP. Results: Sepsis reduced CR500 from 0.73 ± 0.03 to 0.21 ± 0.03, increased nNOS activity from 87 ± 9 to 220 ± 29 pmol/mg/h and nitrite/nitrate from 16 ± 1 to 39 ± 3 , M, without affecting nNOS protein expression. Ascorbate at 0 and 23 h prevented/reversed the conduction deficit and the increases in nNOS activity and nitrite/nitrate level. NO donor SNAP (S -nitroso- N -acetylpenicillamine) reestablished the conduction deficit in ascorbate-treated septic mice. Superoxide scavenger MnTBAP (Mn(III)tetrakis(4-benzoic acid)porphyrin chloride) did not affect this deficit. Conclusion: These data indicate that early and delayed intravenous boluses of ascorbate prevent/reverse sepsis-induced deficit in arteriolar conducted vasoconstriction in the cremaster muscle by inhibiting nNOS-derived NO production. [source] Regulation of skeletal muscle mitochondrial function: genes to proteinsACTA PHYSIOLOGICA, Issue 4 2010I. R. Lanza Abstract The impact of ageing on mitochondrial function and the deterministic role of mitochondria on senescence continue to be topics of vigorous debate. Many studies report that skeletal muscle mitochondrial content and function are reduced with ageing and metabolic diseases associated with insulin resistance. However, an accumulating body of literature suggests that physical inactivity typical of ageing may be a more important determinant of mitochondrial function than chronological age, per se. Reports of age-related declines in mitochondrial function have spawned a vast body of literature devoted to understanding the underlying mechanisms. These mechanisms include decreased abundance of mtDNA, reduced mRNA levels, as well as decreased synthesis and expression of mitochondrial proteins, ultimately resulting in decreased function of the whole organelle. Effective therapies to prevent, reverse or delay the onset of the aforementioned mitochondrial changes, regardless of their inevitability or precise underlying causes, require an intimate understanding of the processes that regulate mitochondrial biogenesis, which necessitates the coordinated regulation of nuclear and mitochondrial genomes. Herein we review the current thinking on regulation of mitochondrial biogenesis by transcription factors and transcriptional co-activators and the role of hormones and exercise in initiating this process. We review how exercise may help preserve mitochondrial content and functionality across the lifespan, and how physical inactivity is emerging as a major determinant of many age-associated changes at the level of the mitochondrion. We also review evidence that some mitochondrial changes with ageing are independent of exercise or physical activity and appear to be inevitable consequences of old age. [source] Effects of short-term food deprivation on orexin-A-induced intestinal bicarbonate secretion in comparison with related secretagoguesACTA PHYSIOLOGICA, Issue 3 2010G. Flemström Abstract Studies of gastrointestinal physiology in humans and intact animals are usually conducted after overnight fast. We compared the effects of orexin-A, vasoactive intestinal polypeptide (VIP), melatonin, serotonin, uroguanylin, ghrelin and prostaglandin E2 (PGE2) on duodenal bicarbonate secretion in fed and overnight fasted animals. This review is a summary of our findings. Secretagogues were administered by intra-arterial infusion or luminally (PGE2). Enterocyte intracellular calcium ([Ca2+]i) signalling was studied by fluorescence imaging. Total RNA was extracted, reverse transcripted to cDNA and expression of orexin receptors measured by quantitative real-time PCR. Orexin-A stimulates the duodenal secretion in continuously fed animals but not in food-deprived animals. Similarly, short-term fasting causes a 100-fold decrease in the amount of the muscarinic agonist bethanechol required for stimulation of secretion. In contrast, fasting does not affect secretory responses to intra-arterial VIP, melatonin, serotonin, uroguanylin and ghrelin, or that to luminal PGE2. Orexin-A induces [Ca2+]i signalling in enterocytes from fed rats but no significant [Ca2+]i responses occur in enterocytes from fasted animals. In addition, overnight fasting decreases the expression of mucosal orexin receptors. Short-term food deprivation thus decreases duodenal expression of orexin receptors and abolishes the secretory response to orexin-A as well as orexin-A-induced [Ca2+]i signalling. Fasting, furthermore, decreases mucosal sensitivity to bethanechol. The absence of declines in secretory responses to other secretagogues tested strongly suggests that short-term fasting does not affect the secretory capacity of the duodenal mucosa in general. Studies of intestinal secretion require particular evaluation with respect to feeding status. [source] Earnings Quality and the Equity Risk Premium: A Benchmark Model,CONTEMPORARY ACCOUNTING RESEARCH, Issue 3 2006Kenton K. Yee Abstract This paper solves a model that links earnings quality to the equity risk premium in an infinite-horizon consumption capital asset pricing model (CAPM) economy. In the model, risk-averse traders hold diversified portfolios consisting of risk-free bonds and shares of many risky firms. When constructing their portfolios, traders rely on noisy reported earnings and dividend payments for information about the risky firms. The main new element of the model is an explicit representation of earnings quality that includes hidden accrual errors that reverse in subsequent periods. The model demonstrates that earnings quality magnifies fundamental risk. Absent fundamental risk, poor earnings quality cannot affect the equity risk premium. Moreover, only the systematic (undiversified) component of earnings-quality risk contributes to the equity risk premium. In contrast, all components of earnings-quality risk affect earnings capitalization factors. The model ties together consumption CAPM and accounting-based valuation research into one price formula linking earnings quality to the equity risk premium and earnings capitalization factors. [source] POST-PASTEURIAN CULTURES: The Microbiopolitics of Raw-Milk Cheese in the United StatesCULTURAL ANTHROPOLOGY, Issue 1 2008HEATHER PAXSON ABSTRACT Out of concern for public health, the U.S. government bans the sale of cheese made from unpasteurized milk if it is aged fewer than 60 days. But while the FDA views raw-milk cheese as a potential biohazard, riddled with pathogenic microbes, aficionados see it as the reverse: as a traditional food processed for safety by the action of good microbes. This article offers a theoretical frame for understanding the recent rise in American artisan raw-milk cheese production, as well as wider debates over food localism, nutrition, and safety. Drawing on ethnographic interviews with cheese makers and purveyors and on participant-labor conducted on a Vermont sheep dairy farm, I develop the concept of microbiopolitics to analyze how farmer,cheese makers, industry consultants, retailers, and consumers negotiate Pasteurian (hygienic) and post-Pasteurian (probiotic) attitudes about the microbial agents at the heart of raw-milk cheese and controversies about this nature,culture hybrid. [source] Thinking about flagellar oscillationCYTOSKELETON, Issue 8 2009Charles J. Brokaw Abstract Bending of cilia and flagella results from sliding between the microtubular outer doublets, driven by dynein motor enzymes. This review reminds us that many questions remain to be answered before we can understand how dynein-driven sliding causes the oscillatory bending of cilia and flagella. Does oscillation require switching between two distinct, persistent modes of dynein activity? Only one mode, an active forward mode, has been characterized, but an alternative mode, either inactive or reverse, appears to be required. Does switching between modes use information from curvature, sliding direction, or both? Is there a mechanism for reciprocal inhibition? Can a localized capability for oscillatory sliding become self-organized to produce the metachronal phase differences required for bend propagation? Are interactions between adjacent dyneins important for regulation of oscillation and bend propagation? Cell Motil. Cytoskeleton 2008. © 2008 Wiley-Liss, Inc. [source] Twenty-five-year course and outcome in anxiety and depression in the Upper Bavarian Longitudinal Community StudyACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2010M. M. Fichter Fichter MM, Quadflieg N, Fischer UC, Kohlboeck G. Twenty-five-year course and outcome in anxiety and depression in the Upper Bavarian Longitudinal Community Study. Objective:, Assessment of 25-year course of pure and mixed anxiety and depression in a community sample. Method:, Participants were grouped into pure anxiety, pure depression, mixed anxiety and depression, and no anxiety or depressive syndrome at baseline. Assessments consisted of a: i) baseline survey, ii) 5-year follow-up, iii) 25-year follow-up. Self-rating scales as well as expert-rating interviews yielded data on social and psychopathological risk factors and outcome measures. Results:, Baseline prevalence for mixed anxiety and depressive syndrome was 8.7%. Subjects with combined anxiety and depressive syndrome were more predisposed towards later adverse mental health outcomes and reduced functionality. The transition from anxiety syndrome (pure and mixed) to depressive syndrome over the 25-year study is more likely than the reverse. Logistic regression analysis emphasized the impact of early anxiety syndromes on later depression. Conclusion:, Results underscore the long-term risks of suffering from a combined anxiety and depressive syndrome. [source] Individuation of pairs of objects in infancyDEVELOPMENTAL SCIENCE, Issue 4 2007Alan M. Leslie Looking-time studies examined whether 11-month-old infants can individuate two pairs of objects using only shape information. In order to test individuation, the object pairs were presented sequentially. Infants were familiarized either with the sequential pairs, disk-triangle/disk-triangle (XY/XY), whose shapes differed within but not across pairs, or with the sequential pairs, disk-disk/triangle-triangle (XX/YY), whose shapes differed across but not within pairs. The XY/XY presentation looked to adults like a single pair of objects presented repeatedly, whereas the XX/YY presentation looked like different pairs of objects. Following familiarization to these displays, infants were given a series of test trials in which the screen was removed, revealing two pairs of objects in one of two outcomes, XYXY or XXYY. On the first test trial, infants familiarized with the identical pairs (XY/XY) apparently expected a single pair to be revealed because they looked longer than infants familiarized with the distinct pairs (XX/YY). Infants who had seen the distinct pairs apparently expected a double pair outcome. A second experiment showed outcomes of a single XY pair. This outcome is unexpected for XX/YY-familiarized infants but expected for XY/XY-familiarized infants, the reverse of Experiment 1. This time looking times were longer for XX/YY infants. Eleven-month-olds appear to be able to represent not just individual objects but also pairs of objects. These results suggest that if they can group the objects into sets, infants may be able to track more objects than their numerosity limit or available working memory slots would normally allow. We suggest possible small exact numerosity representations that would allow tracking of such sets. [source] Medium-term outcome of fundoplication after lung transplantationDISEASES OF THE ESOPHAGUS, Issue 8 2009P. R. Burton SUMMARY Gastroesophageal reflux disease (GERD) in lung transplant recipients has gained increasing attention as a factor in allograft failure. There are few data on the impact of fundoplication on survival or lung function, and less on its effect on symptoms or quality of life. Patients undergoing fundoplication following lung transplantation from 1999 to 2005 were included in the study. Patient satisfaction, changes in GERD symptoms, and the presence of known side effects were assessed. The effect on lung function, body mass index, and rate of progression to the bronchiolitis obliterans syndrome (BOS) were recorded. Twenty-one patients (13 males), in whom reflux was confirmed on objective criteria, were included, with a mean age of 43 years (range 20,68). Time between transplantation and fundoplication was 768 days (range 145,1524). The indication for fundoplication was suspected microaspiration in 13 and symptoms of GERD in 8. There was one perioperative death, at day 17. There were three other late deaths. Fundoplication did not appear to affect progression to BOS stage 1, although it may have slowed progression to stage 2 and 3. Forced expiratory volume-1% predicted was 72.9 (20.9), 6 months prior to fundoplication and 70.4 (26.8), six months post-fundoplication, P= 0.33. Body mass index decreased significantly in the 6 months following fundoplication (23 kg/m2 vs. 21 kg/m2, P= 0.05). Patients were satisfied with the outcome of the fundoplication (mean satisfaction score 8.8 out of 10). Prevalence of GERD symptoms decreased significantly following surgery (11 of 14 vs. 4 of 17, P= 0.002). Fundoplication does not reverse any decline in lung function when performed at a late stage post-lung transplantation in patients with objectively confirmed GERD. It may, however, slow progression to the more advanced stages of BOS. Reflux symptoms are well controlled and patients are highly satisfied. Whether performing fundoplication early post-lung transplant in selected patients can prevent BOS and improve long-term outcomes requires formal evaluation. [source] Contractile Reserve Assessed Using Dobutamine Echocardiography Predicts Left Ventricular Reverse Remodeling after Cardiac Resynchronization Therapy: Prospective Validation in Patients with Left Ventricular DyssynchronyECHOCARDIOGRAPHY, Issue 6 2010F.R.C.P.C., Mario Sénéchal M.D. Background: The presence of viable myocardium may predict response to cardiac resynchronization therapy (CRT). The aim of this study is to evaluate in patients with left ventricular (LV) dyssynchrony whether response to CRT is related to myocardial viability in the region of the pacing lead. Methods: Forty-nine consecutive patients with advanced heart failure, LV ejection fraction < 35%, QRS duration > 120 ms and intraventricular asynchronism , 50 ms were included. Dobutamine stress echocardiography was performed within the week before CRT implantation. Resting echocardiography was performed 6 months after CRT implantation. Viability in the region of LV pacing lead was defined as the presence of viability in two contiguous segments. Response to CRT was defined by evidence of reverse LV remodeling (,15% reduction in LV end-systolic volume). Results: Thirty-one patients (63%) were identified as responders at follow-up. The average of viable segments was 5.9 ± 2 in responders and 3.2 ± 3 in nonresponders (P = 0.0003). Viability in the region of the pacing lead had a sensitivity of 94%, a specificity of 67%, a positive predictive value of 83%, and a negative predictive value of 86% for the prediction of response to CRT. Conclusions: In patients with LV dyssynchrony, reverse remodeling after CRT requires viability in the region of the pacing lead. This simple method using echocardiography dobutamine for the evaluation of local viability (i.e., viability in two contiguous segments) may be useful to the clinician in choosing the best LV lead positioning. (Echocardiography 2010;27:668-676) [source] Complex networks: two ways to be robust?ECOLOGY LETTERS, Issue 6 2002Carlos J. Melián Abstract Recent studies of biological networks have focused on the distribution of the number of links per node. However, the connectivity distribution does not uncover all the complexity of their topology. Here, we analyse the relation between the connectivity of a species and the average connectivity of its nearest neighbours in three of the most resolved community food webs. We compare the pattern arising with the one recently reported for protein networks and for a simple null model of a random network. Whereas two highly connected nodes are unlikely to be connected between each other in protein networks, the reverse happens in food webs. We discuss this difference in organization in relation to the robustness of biological networks to different types of perturbation. [source] Changes in per capita alcohol sales during the partial privatization of British Columbia's retail alcohol monopoly 2003,2008: a multi-level local area analysisADDICTION, Issue 11 2009Tim Stockwell ABSTRACT Aim To investigate the independent effects on liquor sales of an increase in (a) the density of liquor outlets and (b) the proportion of liquor stores in private rather than government ownership in British Columbia between 2003/4 and 2007/8. Design The British Columbia Liquor Distribution Branch provided data on litres of ethanol sold through different types of outlets in 89 local health areas of the province by beverage type. Multi-level regression models were used to examine the relationship between per capita alcohol sales and outlet densities for different types of liquor outlet after adjusting for potential confounding social, economic and demographic factors as well as spatial and temporal autocorrelation. Setting Liquor outlets in 89 local health areas of British Columbia, Canada. Findings The number of private stores per 10 000 residents was associated significantly and positively with per capita sales of ethanol in beer, coolers, spirits and wine, while the reverse held for government liquor stores. Significant positive effects were also identified for the number of bars and restaurants per head of population. The percentage of liquor stores in private versus government ownership was also associated significantly with per capita alcohol sales when controlling for density of liquor stores and of on-premise outlets (P < 0.01). Conclusion The trend towards privatisation of liquor outlets between 2003/04 and 2007/08 in British Columbia has contributed to increased per capita sales of alcohol and hence possibly also to increased alcohol-related harm. [source] Measurement of electrophoretic mobility of cardiomyocytesELECTROPHORESIS, Issue 21 2009Ying Zhou Abstract The electrophoretic mobility (EPM) of rat cardiomyocytes with or without the treatment of neuraminidase was studied by cell electrophoresis. The EPM was found to change over a range from 0 to 8.67,,m,s,1/V,cm,1, depending on ionic strength, transmembrane potential, pH value, and/or surface charges. It is interesting that zero EPM was observed but reverse of the mobility was not. These results suggested that the negative charges carried on the cardiomyocyte surface might comprehensively consist of surface sialic acid, plasmalemma proteins, phospholipids, and transmembrane potential. The aberrant electrical double layer formed between the carried negative charges and adions had a big adsorption layer and a diffusion layer whose sizes changed circularly, making only negative charges be carried on the surface of living cardiomyocytes. The special structures on the surface of cardiomyocytes probably play a considerable role in the process of cardiac electrical activity. [source] Semiquantitative determination of Alicyclobacillus acidoterrestris in orange juice by reverse- transcriptase polymerase chain reaction and capillary electrophoresis , laser induced fluorescence using microchip technologyELECTROPHORESIS, Issue 21-22 2004Maribel Funes-Huacca Abstract The semiquantitative detection of Alicyclobacillus acidoterrrestris in orange juice by reverse-transcriptase polymerase chain reaction (RT-PCR) with a linear dynamic range of 2×105, 2 colony forming units (CFU)/mL in terms of cell count is described. Separation, detection, and quantification of the RT-PCR products were accomplished using the Agilent 2100 bioanalyzer in conjunction with the DNA 1000 LabChip kit. After 0 and 12 h of enrichment, it was possible to generate a linear standard curve between the amount of cells and amplicon concentration of RT-PCR and PCR products. Using this method, cell diminution was verified in samples of orange juice treated with a natural inhibitor (Sapindus saponaria), determining the persistence of viable cells. Semiquantitative RT-PCR using the Agilent 2100 bioanalyzer is a potentially useful approach for rapid in vitro determination of A. acidoterrestris and monitoring of inhibitor susceptibility for the orange juice-producing industry. [source] Small-scaled geographical variation in life-history traits of the blowfly Calliphora vicina between rural and urban populationsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2009C. C. Hwang Abstract The impact of the urban heat-island effect, the warming-up of an urban area caused by human activity, on the blowfly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) was examined at two British sites, 30 km apart. Waterloo in Central London is a highly urbanised built-up area, whereas Box Hill in the county of Surrey is a rural pasture and woodland location. The phenotypic plasticity of 12 C. vicina cultures, originated from single females from each of the two sites, was measured using three developmental characters: adult body size (represented as the length of the cross vein dm-cu of the right wing), development time as accumulated degree-days (ADD), and growth rate (length of dm-cu/ADD), along a constant temperature series of 16, 20, 24, and 28 °C in the laboratory. The blowflies from Box Hill had the same ADD as those from Waterloo, but showed a significantly larger adult size and growth rate at lower temperatures, suggesting the existence of local adaptations that may be caused by the differing levels of urbanisation between the two studied sites. Not surprisingly, a trade-off between adult size and development time was found. Females showed longer development times than males at all four temperatures, indicating they may need to ingest more food as larvae to furnish ovarioles and increase fecundity. However, females had larger adult size than males at 16 and 20 °C but a reverse at 28 °C, suggesting that females may be more cold-adapted than males. [source] Sorption irreversibility of 1,4-dichlorobenzene in two natural organic matter,rich geosorbentsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2009Michael Sander Abstract Hysteresis, a frequently observed phenomenon in sorption studies, is inconsistent with the key assumption of sorption reversibility in most fate and bioavailability models. Therefore, a study of the underlying causes of hysteresis is essential. Carbon-radiolabeled 1,4-dichlorobenzene (DCB) isotope tracer exchange was carried out at select points along the isotherms of DCB in a brown coal and a peat soil, holding total DCB concentration constant. Tracer exchange was performed both in the forward (sorption) and reverse (desorption) directions at the bulk sorption points and in the desorption direction at the corresponding bulk desorption points. Bulk DCB isotherms showed concentration-dependent hysteresis. However, tracer reequilibration in all cases was consistent with free exchange between sorbed and aqueous-phase molecules. These results rule out common experimental artifacts and demonstrate that sorption of bulk DCB is truly hysteretic (i.e., irreversible). The differences in rates between bulk and tracer sorption and desorption are consistent with the coupling of bulk DCB diffusion to other processes that retard equilibration, which we assign to matrix swelling or shrinking. Hysteresis is attributed to matrix deformation,specifically, to inelastic expansion and creation of voids accommodating sorbate molecules in the matrix, which leads to enhanced affinity in the desorption step. Comparing the results to previous results for naphthalene in the coal, we find that irreversible effects are similar for DCB and naphthalene in the coal but differ for DCB between the two sorbents. An explanation based on the different physical properties of these sorbents is provided. Solid-phase extraction of equilibrated DCB with Tenax® revealed a highly desorption-resistant fraction. While too small to account for the observed hysteresis, this fraction may represent molecules that become trapped as the matrix collapses and simultaneously stiffens during abrupt desorption. [source] | |||||||||||||||||||||||||||||||||||||