bluuebunny/crossref_metadata_2025 huggingface dataset:
Stroke Incidence Is Decreasing in Whites But Not in Blacks
Authors: Kleindorfer Dawn O. , Khoury Jane , Moomaw Charles J. , Alwell Kathleen , Woo Daniel , Flaherty Matthew L. , Khatri Pooja , Adeoye Opeolu , Ferioli Simona , Broderick Joseph P. , Kissela Brett M.
Published: May 2010

Background and Purpose—

Although other studies (in largely white populations) have found that stroke incidence declined during the 1990s, we previously reported that stroke incidence in our population (18% of which was black) did not change during that decade and that incidence rates in blacks were significantly higher than in whites. We sought to update temporal trends in stroke incidence by adding new data obtained from our large, biracial population in 2005. The objective of this study was to examine temporal trends in stroke incidence and case-fatality within a large biracial population over time by comparing stroke incidence rates from 1993 to 1994, 1999, and 2005.

Methods—

Within the Greater Cincinnati/Northern Kentucky population of 1.3 million, all strokes among area residents were ascertained at all local hospitals during July 1993 to June 19/94 and calendar years 1999 and 2005. A sampling scheme was used to ascertain cases in the out-of-hospital setting. Only first-ever strokes were included in this analysis. Race-specific incidence rates, standardized to the 2000 US Census population, and case-fatality rates were calculated.

Results—

The number of physician-confirmed first-ever strokes in patients ≥20 years of age was 1942 in 1993 to 1994, 2041 in 1999, and 1921 in 2005. In all study periods, blacks had higher stroke incidence than whites, and case-fatality rates were similar between races. In contrast to previous study periods, we found a significant decrease in overall stroke incidence in 2005. When stratified by race and stroke subtype, this change was driven by a decrease in ischemic stroke incidence among whites, whereas ischemic stroke incidence in blacks was unchanged. Hemorrhagic stroke incidence was unchanged in both races.

Conclusions—

For the first time, we report a significant decrease in stroke incidence within our population, which is consistent with other reports in the literature. This decrease was found only among whites, which suggests a worsening of the racial disparity in stroke incidence.
Analysis of Intraseasonal and Interannual Variability of the Asian Summer Monsoon Using a Hidden Markov Model
Authors: Yoo Jin Ho , Robertson Andrew W. , Kang In-Sik
Published: May 2010

Intraseasonal and interannual variability of Asian summer monsoon rainfall in pentad precipitation data is examined using a hidden Markov model (HMM). The spatial patterns of discrete rainfall states derived with the HMM and the associated transition probabilities between the states are shown to represent well the principal Asian summer monsoon intraseasonal oscillation (ISO), propagating eastward and northward with a period of 40–50 days. Stochastic simulations made with the HMM reasonably reproduce the canonical ISO propagation and its observed statistics such as the frequency of ISO events.

The interannual modulation of the ISO associated with El Niño–Southern Oscillation (ENSO) is assessed by employing a nonhomogeneous HMM (NHMM) with summer-mean Niño-3.4 index prescribed as an input variable. ENSO influence on the ISO is found to manifest as preferences toward particular ISO phases depending on the ENSO condition, thus adding an asymmetry to the ISO. In the presence of seasonal mean anomalies, it is shown that the El Niño seasonal mean rainfall anomaly pattern is identified by the HMM as a distinct state, in addition to the ISO states, whereas the La Niña seasonal mean rainfall anomaly pattern does not appear distinct from the ISO states.
Multiscale Momentum Flux and Diffusion due to Whitecapping in Wave–Current Interactions
Authors: Restrepo Juan M. , Ramírez Jorge M. , McWilliams James C. , Banner Michael
Published: May 2010

Whitecapping affects the Reynolds stresses near the ocean surface. A model for the conservative dynamics of waves and currents is modified to include the averaged effect of multiple, short-lived, and random wave-breaking events on large spatiotemporal scales. In this study’s treatment, whitecapping is parameterized stochastically as an additive uncertainty in the fluid velocity. It is coupled to the Stokes drift as well as to the current velocity in the form of nonlinear momentum terms in the vortex force and the Bernoulli head. The effects of whitecapping on tracer dynamics, mass balances, and boundary conditions are also derived here. Whitecapping also modifies the dynamics and the size of the sea surface boundary layer. This study does not resolve the boundary layer, however, the authors appeal to traditional viscosity parameterizations to include these diffusive effects, modified for the context of wave–current interactions.

The parameterized breaking velocity field is endowed with empirical rules that link their generation in space and time to properties and dynamics of wave groups. The energy convergence rate of wave groups is used as an indicator for the onset of wave breaking. A methodology is proposed for evaluating this criterion over an evolving random Gaussian model for the ocean surface. The expected spatiotemporal statistics of the breaking events are not imposed, but rather computed, and are found to agree with the general expectation of its Poisson character. The authors also compute, rather than impose, the shear stress associated with the breaking events and find it to agree with theoretical expectations.

When the relative role played by waves and breaking events on currents is compared, this study finds that waves, via the vortex force, purely advect the vorticity of currents that are essentially only dependent on transverse coordinates. The authors show that currents will tend to get rougher in the direction of steady wind, when whitecapping is present. Breaking events can alter and even suppress the rate of advection in the vortex force. When comparing the rates of transport, the waves will tend to dominate the short term and the whitecapping of the long-term rate.
Optical Characteristics of OTD Flashes and the Implications for Flash-Type Discrimination
Authors: Koshak W. J.
Published: May 2010

Flashes detected by the Optical Transient Detector (OTD) that occur over the continental United States (CONUS) are intercompared with data from the National Lightning Detection Network (NLDN) in order to partition the OTD flashes into ground and cloud flashes. The entire 5-yr OTD dataset for CONUS is analyzed. The statistical distributions of a variety of optical characteristics are examined, including five flash-level attributes (radiance, area, duration, number of optical groups, and number of optical events), and two group-level attributes [the maximum number of events in a group (MNEG), and a closely related parameter, the maximum group area (MGA)]. On average, there were 5.6 optical groups per return stroke in a ground flash, which is in part due to the likelihood that OTD detects interstroke K changes. It was found that return strokes within ground flashes typically produce large optical groups; hence, the MNEG and MGA parameters serve as useful “return-stroke detectors.” The results of this study provide insight on how to construct an algorithm for retrieving the fraction of ground flashes in a set of flashes observed from a satellite lightning imager. Specifically, even though it is shown that the statistical distributions of the optical characteristics for ground and cloud flashes overlap substantially, the mean values of these distributions differ. Hence, a retrieval method that is based on an analysis of the distribution of the means, and that employs the central limit theorem of statistics, is recommended. As the sample size used to compute the means is increased, the overlap in the distributions of the means for ground and cloud flashes is diminished, making ground flash fraction retrieval feasible. Of the seven optical characteristics examined here, the mean MNEG and mean MGA parameters are suggested as being the most useful for discriminating between ground and cloud flashes in the context of this “central limit theorem” approach.
Wave Heights during Hurricane Katrina: An Evaluation of PPP and PPK Measurements of the Vertical Displacement of the GPS Antenna
Authors: Bender L. C. , Howden S. D. , Dodd D. , Guinasso N. L.
Published: May 2010

In August 2005 the eye of Hurricane Katrina passed 49 n mi to the west of a 3-m discus buoy operated by the Central Gulf of Mexico Ocean Observing System (CenGOOS). Buoy motions were measured with a strapped-down 6 degrees of freedom accelerometer, a three-axis magnetometer, and a survey-grade GPS receiver. The significant wave heights were computed from the buoy’s accelerometer record and from the dual-frequency GPS measurements that were processed in two different ways. The first method was postprocessed kinematic (PPK) GPS, which requires another GPS receiver at a fixed known location, and the other was precise point positioning (PPP) GPS, which is another postprocessed positioning technique that yields absolute rather than differential positions. Unlike inertial measurement units, either GPS technique can be used to obtain both waves and water levels. The purpose of this note is to demonstrate the excellent reliability and accuracy of both methods for determining wave heights and periods from a GPS record. When the motion of the GPS antenna is properly understood as the motion of the buoy deck and not the true vertical motion of the sea surface, the GPS wave heights are as reliable as a strapped-down 1D accelerometer.
Formation of Charge Structures in a Supercell
Authors: Bruning Eric C. , Rust W. David , MacGorman Donald R. , Biggerstaff Michael I. , Schuur Terry J.
Published: May 2010

Lightning mapping, electric field, and radar data from the 26 May 2004 supercell in central Oklahoma are used to examine the storm’s charge structure. An initial arc-shaped maximum in lightning activity on the right flank of the storm’s bounded weak echo region was composed of an elevated normal polarity tripole in the region of precipitation lofted above the storm’s weak echo region. Later in the storm, two charge structures were associated with precipitation that reached the ground. To the left of the weak echo region, six charge regions were inferred, with positive charge carried on hail at the bottom of the stack. Farther forward in the storm’s precipitation region, four charge regions were inferred, with negative charge at the bottom of the stack. There were different charge structures in adjacent regions of the storm at the same time, and regions of opposite polarity charge were horizontally adjacent at the same altitude. Flashes occasionally lowered positive charge to ground from the forward charge region. A conceptual model is presented that ties charge structure in different regions of the storm to storm structure inferred from radar reflectivity.
Effect of Sodium Alginate on Acid Gastroesophageal Reflux Disease in Preterm Infants: A Pilot Study
Authors: Atasay Begum , Erdeve Omer , Arsan Saadet , Türmen Tomris
Published: May 2010

The objective of this study was to evaluate the effect of the antireflux barrier formed by Na alginate on pH‐metry‐defined acid reflux events in preterms. Four times/day, 1 mL/kg of Na alginate was administered as an intervention to the preterm infants whose gastroesophageal reflux disease was confirmed by 24‐hour pH monitoring, and the measurement was repeated after 48 hours. The major outcomes were improvement in the number of reflux events per 24 hours, the duration of the longest episode, the number of episodes >5 minutes per 24 hours, and reflux index on pH‐metry. Thirty‐four (83%) of 41 preterm infants who completed the study had pathologic measurement on 24‐hour pH monitoring; 27 (83%) of the patients responded to treatment, whereas 7 patients (17%) did not. Na alginate treatment significantly improved the number of episodes with pH <4 per 24 hours, the reflux index, the number of episodes >5 minutes with pH <4, and the duration of longest episode with pH <4. Patients showed significant improvement in 2 evaluated clinical symptoms, which were vomiting and weight gain after the treatment. No side effect except thickening of stool in 3 patients was observed. Na alginate treatment for gastroesophageal reflux disease in preterm infants seems to be safe and effective.
The Myth of “the” Micro-Macro Divide: Bridging System-Level and Disciplinary Divides
Authors: Molloy Janice C. , Ployhart Robert E. , Wright Patrick M.
Published: May 2010

We clarify that management scholars do not have a shared conceptualization of what the terms micro and macro mean. Therefore, there is not one, but rather there are multiple micro—macro divides within management. Specifically, there are three micro—macro divides that separate scholarship at three levels of the social and economic systems that management scholars study. These system levels include individuals and groups, organizations, and the broader social and economic systems (which contain individuals and organizations—such as industries, labor markets, and societies). Scholarship at these three system levels is often based in different disciplines. For example, scholarship on individuals and groups is often based in psychology whereas scholarship regarding organizations and social and economic systems is often based in economics or sociology. Yet there are fundamental differences in the theoretical assumptions and methodological traditions underlying these disciplines. We call these differences disciplinary divides and argue that because disciplinary divides oftentimes coexist with system-level divides, scholars bridging system levels need to be cognizant of disciplinary divides. The purpose of this article is to help scholars bridge these divides. To this end, we first identify the nature and specific types of divides. We then present a content analysis of 300 articles as a snapshot of the extent to which bridging scholarship is conducted. Finally, we provide a road-map that details the specific intellectual steps required to bridge system-level and disciplinary divides and make one’s scholarship more accessible to scholars from other disciplines and management subdomains.
Merleau-Ponty’s phenomenology of politics: A humanism in extension
Authors: Melançon Jérôme
Published: May 2010

Merleau-Ponty’s phenomenology also extends to politics, which he does not only understand from a Marxist point of view. In his articles on Montaigne and Machiavelli, he operates a reduction of the political subject in order to show how it is always already involved in the world, in history and in political affairs, how these phenomena appear to it, and how it can act. In this light, the ‘Preface’ to Humanism and Terror presents both a description of the demands of political judgment and action, and a statement of Merleau-Ponty’s position as a political subject in postwar France.
The business of expectations: How promissory organizations shape technology and innovation
Authors: Pollock Neil , Williams Robin
Published: May 2010

The business of technological expectations has yet to be explored thoroughly by scholars interested in the role of expectations and visions in the emergence of technological innovations. However, intermediaries specializing in the production, commodification and selling of future-oriented knowledge have emerged to exert new kinds of influence on the shaping of technology and innovation. We focus on the work of those specialist forms of consultants known as ‘industry analysts’ and consider them as promissory organizations to capture how they are successful in mobilizing and indeed increasingly organizing expectations within procurement and innovation markets. Our aim is to highlight the important role these actors play in shaping technologies and, in so doing, to show how they typically exhibit complex and highly uneven forms of influence. The paper is organized around a central question: Why are certain kinds of promissory behaviour more influential than others? To answer this, we draw from discussions of the ‘constitutive’ nature of promises in the literature on technology expectations, which provide a useful but arguably partial analytical approach for articulating the dynamics and differences surrounding product based expectations. We thus supplement our understanding with recent developments in Economic Sociology and the Sociology of Finance where an ambitious theoretical framework is unfolding in relation to the ‘performativity of economic theory’. By contrasting different forms of promissory work conducted by industry analysts and varying forms of accountability to which this work is subject, we begin to map out a typology that characterises promissory behaviour according to differences in kind and effect.
Promoting Community Empowerment Among Rural Tibetans in China Using Focus Group Discussions
Authors: Ljunggren Anethe , Zuli Huang  , Fang Wang  , Johansson Eva
Published: May 2010

We had two aims in conducting this study: to explore if focus group discussions (FGDs) could empower rural Tibetans in Western China to recognize their own needs and potential, and to investigate if the process could be monitored by way of repeat FGDs. Five FGDs were conducted among each of three focus groups (FGs) over a 5-year period, amounting to 15 FGDs. The FG participants also took part in volunteer training and in community practice. Content analysis was used to analyze the transcripts of the FGD sessions. Our findings indicate that repeat FGDs can be used as a tool to monitor the process of community empowerment. The method can motivate community members to take part in their own development, improve their self-awareness, and help them become conscious of the real issues facing the community.
Lack of Identification of Asthmatic Players in a Youth Soccer League
Authors: Weiss Pnina , Bazzy-Asaad Alia , Tolomeo Concettina
Published: May 2010

Exercise-induced bronchoconstriction occurs in 10% to 15% of the general population and in up to 40% of youth soccer players. Sports-induced asthma exacerbations are a well-recognized cause of death in children. The aim of this descriptive study was to determine whether coaches and managers of a youth soccer league were aware of which players on their team carried the diagnosis of asthma or used bronchodilators and whether they had an emergency asthma action plan for these players. Secondary outcomes were the coaches’ and managers’ knowledge of asthma. Data collection consisted of a multiple-choice survey that was sent to 58 volunteer parent coaches and managers of a Connecticut town soccer organization. Twenty-nine (50%) coaches and managers responded to the survey; they supervised a total of 376 children. Most coaches and managers were not sure which players on their team had asthma (16, 55%) or used inhalers (17, 59%). Five (17%) coaches and managers identified 6 children who used an inhaler; 5 of the children had their inhalers on the field for both practices and games. Most (22, 85%) never discussed an asthma action plan with parents or players. Most (16, 67%) felt that they did not know how to treat an asthma attack. Approximately half demonstrated knowledge about the use of bronchodilator for asthma exacerbations (10) and preexercise treatment (12). This is the first study describing asthma awareness and knowledge in a youth soccer league. Findings demonstrated a lack of both awareness and knowledge in supervising coaches and managers. Children in this age group have the highest risk of dying from sports-related asthma and symptoms. Therefore, it is critical to understand the reasons for this lack of awareness and to address it. Asthma education can play an integral role in addressing this deficiency.
Evolutionary ancestry and novel functions of the mammalian glucose transporter (GLUT) family
Authors: Wilson-O'Brien Amy L , Patron Nicola , Rogers Suzanne
Published: May 2010

Background

In general, sugar porters function by proton-coupled symport or facilitative transport modes. Symporters, coupled to electrochemical energy, transport nutrients against a substrate gradient. Facilitative carriers transport sugars along a concentration gradient, thus transport is dependent upon extracellular nutrient levels. Across bacteria, fungi, unicellular non-vertebrates and plants, proton-coupled hexose symport is a crucial process supplying energy under conditions of nutrient flux. In mammals it has been assumed that evolution of whole body regulatory mechanisms would eliminate this need. To determine whether any isoforms bearing this function might be conserved in mammals, we investigated the relationship between the transporters of animals and the proton-coupled hexose symporters found in other species.

Results

We took a comparative genomic approach and have performed the first comprehensive and statistically supported phylogenetic analysis of all mammalian glucose transporter (GLUT) isoforms. Our data reveals the mammalian GLUT proteins segregate into five distinct classes. This evolutionary ancestry gives insight to structure, function and transport mechanisms within the groups. Combined with biological assays, we present novel evidence that, in response to changing nutrient availability and environmental pH, proton-coupled, active glucose symport function is maintained in mammalian cells.

Conclusions

The analyses show the ancestry, evolutionary conservation and biological importance of the GLUT classes. These findings significantly extend our understanding of the evolution of mammalian glucose transport systems. They also reveal that mammals may have conserved an adaptive response to nutrient demand that would have important physiological implications to cell survival and growth.
Adenosine thiamine triphosphate accumulates in Escherichia coli cells in response to specific conditions of metabolic stress
Authors: Gigliobianco Tiziana , Lakaye Bernard , Wins Pierre , El Moualij Benaïssa , Zorzi Willy , Bettendorff Lucien
Published: May 2010

Background

E. coli cells are rich in thiamine, most of it in the form of the cofactor thiamine diphosphate (ThDP). Free ThDP is the precursor for two triphosphorylated derivatives, thiamine triphosphate (ThTP) and the newly discovered adenosine thiamine triphosphate (AThTP). While, ThTP accumulation requires oxidation of a carbon source, AThTP slowly accumulates in response to carbon starvation, reaching ~15% of total thiamine. Here, we address the question whether AThTP accumulation in E. coli is triggered by the absence of a carbon source in the medium, the resulting drop in energy charge or other forms of metabolic stress.

Results

In minimal M9 medium, E. coli cells produce AThTP not only when energy substrates are lacking but also when their metabolization is inhibited. Thus AThTP accumulates in the presence of glucose, when glycolysis is blocked by iodoacetate, or in the presence lactate, when respiration is blocked by cyanide or anoxia. In both cases, ATP synthesis is impaired, but AThTP accumulation does not appear to be a direct consequence of reduced ATP levels. Indeed, in the CV2 E. coli strain (containing a thermolabile adenylate kinase), the ATP content is very low at 37°C, even in the presence of metabolizable substrates (glucose or lactate) and under these conditions, the cells produce ThTP but not AThTP. Furthermore, we show that ThTP inhibits AThTP accumulation. Therefore, we conclude that a low energy charge is not sufficient to trigger AThTP accumulation and the latter can only accumulate under conditions where no ThTP is synthesized. We further show that AThTP production can also be induced by the uncoupler CCCP but, unexpectedly, this requires the presence of pyruvate or a substrate yielding pyruvate (such a D-glucose or L-lactate). Under the conditions described, AThTP production is not different when RelA or SpoT mutants are used.

Conclusions

In E. coli, AThTP accumulates in response to two different conditions of metabolic stress: lack of energy substrates (or inhibition of their metabolization) and uncoupled pyruvate oxidation. Both conditions prevent bacterial growth. There is no obvious link with the stringent response or catabolite repression.
A descriptive analysis of child-relevant systematic reviews in the Cochrane Database of Systematic Reviews
Authors: Bow Simon , Klassen Jeffrey , Chisholm Annabritt , Tjosvold Lisa , Thomson Denise , Klassen Terry P , Moher David , Hartling Lisa
Published: May 2010

Background

Systematic reviews (SRs) are considered an important tool for decision-making. There has been no recent comprehensive identification or description of child-relevant SRs. A description of existing child-relevant SRs would help to identify the extent of available child-relevant evidence available in SRs and gaps in the evidence base where SRs are required. The objective of this study was to describe child-relevant SRs from the Cochrane Database of Systematic Reviews (CDSR, Issue 2, 2009).

Methods

SRs were assessed for relevance using pre-defined criteria. Data were extracted and entered into an electronic form. Univariate analyses were performed to describe the SRs overall and by topic area.

Results

The search yielded 1666 SRs; 793 met the inclusion criteria. 38% of SRs were last assessed as up-to-date prior to 2007. Corresponding authors were most often from the UK (41%). Most SRs (59%) examined pharmacological interventions. 53% had at least one external source of funding. SRs included a median of 7 studies (IQR 3, 15) and 679 participants (IQR 179, 2833). Of all studies, 48% included only children, and 27% only adults. 94% of studies were published in peer-reviewed journals. Primary outcomes were specified in 72% of SRs. Allocation concealment and the Jadad scale were used in 97% and 25% of SRs, respectively. Adults and children were analyzed separately in 12% of SRs and as a subgroup analysis in 14%. Publication bias was assessed in only 14% of SRs. A meta-analysis was conducted in 68% of SRs with a median of 5 trials (IQR 3, 9) each. Variations in these characteristics were observed across topic areas.

Conclusions

We described the methodological characteristics and rigour of child-relevant reviews in the CDSR. Many SRs are not up-to-date according to Cochrane criteria. Our study describes variation in conduct and reporting across SRs and reveals clinicians' ability to access child-specific data.
Design of the Anti-tuberculosis Drugs induced Adverse Reactions in China National Tuberculosis Prevention and Control Scheme Study (ADACS)
Authors: Xia Yin Yin , Hu Dai Yu , Liu Fei Ying , Wang Xiao Meng , Yuan Yan Li , Tu De Hua , Chen Yi Xin , Zhou Lin , Zhu Li Zhen , Gao Wei Wei , Wang Hong Yuan , Chen Da Fang , Yang Li , He Ping Ping , Li Xiao Ting , He Ying Jian , Sun Feng , Zhan Si Yan
Published: May 2010

Background

More than 1 million tuberculosis (TB) patients are receiving the standard anti-TB treatment provided by China National Tuberculosis Prevention and Control Scheme (CNTS) in China every year. Adverse reactions (ADRs) induced by anti-TB drugs could both do harm to patients and lead to anti-TB treatment failure. The ADACS aimed to explore ADRs' incidences, prognoses, economical and public health impacts for TB patients and TB control, and build a DNA bank of TB patients.

Methods/Design

Multiple study designs were adopted. Firstly, a prospective cohort with 4488 sputum smears positive pulmonary tuberculosis patients was established. Patients were followed up for 6-9 months in 52 counties of four regions. Those suspected ADRs should be checked and confirmed by Chinese State Food and Drug Administration (SFDA). Secondly, if the suspected ADR was anti-TB drug induced liver injury (ATLI), a nested case-control study would be performed which comprised choosing a matched control and doing a plus questionnaire inquiry. Thirdly, health economical data of ADRs would be collected to analyze financial burdens brought by ADRs and cost-effectiveness of ADRs' treatments. Fourthly, a drop of intravenous blood for each patient was taken and saved in FTA card for DNA banking and genotyping. Finally, the demographic, clinical, environmental, administrative and genetic data would be merged for the comprehensive analysis.

Discussion

ADACS will give an overview of anti-TB drugs induced ADRs' incidences, risk factors, treatments, prognoses, and clinical, economical and public health impacts for TB patients applying CNTS regimen in China, and provide suggestions for individualized health care and TB control policy.
Reduced evolvability of Escherichia coli MDS42, an IS-less cellular chassis for molecular and synthetic biology applications
Authors: Umenhoffer Kinga , Fehér Tamás , Balikó Gabriella , Ayaydin Ferhan , Pósfai János , Blattner Frederick R , Pósfai György
Published: May 2010

Background

Evolvability is an intrinsic feature of all living cells. However, newly emerging, evolved features can be undesirable when genetic circuits, designed and fabricated by rational, synthetic biological approaches, are installed in the cell. Streamlined-genome E. coli MDS42 is free of mutation-generating IS elements, and can serve as a host with reduced evolutionary potential.

Results

We analyze an extreme case of toxic plasmid clone instability, and show that random host IS element hopping, causing inactivation of the toxic cloned sequences, followed by automatic selection of the fast-growing mutants, can prevent the maintenance of a clone developed for vaccine production. Analyzing the molecular details, we identify a hydrophobic protein as the toxic byproduct of the clone, and show that IS elements spontaneously landing in the cloned fragment relieve the cell from the stress by blocking transcription of the toxic gene. Bioinformatics analysis of sequence reads from early shotgun genome sequencing projects, where clone libraries were constructed and maintained in E. coli, suggests that such IS-mediated inactivation of ectopic genes inhibiting the growth of the E. coli cloning host might happen more frequently than generally anticipated, leading to genomic instability and selection of altered clones.

Conclusions

Delayed genetic adaptation of clean-genome, IS-free MDS42 host improves maintenance of unstable genetic constructs, and is suggested to be beneficial in both laboratory and industrial settings.
Inhibition of nuclear factor-kappa B differentially affects thyroid cancer cell growth, apoptosis, and invasion
Authors: Bauerle Kevin T , Schweppe Rebecca E , Haugen Bryan R
Published: May 2010

Background

Nuclear factor-κB (NF-κB) is constitutively activated in many cancers and plays a key role in promoting cell proliferation, survival, and invasion. Our understanding of NF-κB signaling in thyroid cancer, however, is limited. In this study, we have investigated the role of NF-κB signaling in thyroid cancer cell proliferation, invasion, and apoptosis using selective genetic inhibition of NF-κB in advanced thyroid cancer cell lines.

Results

Three pharmacologic inhibitors of NF-κB differentially inhibited growth in a panel of advanced thyroid cancer cell lines, suggesting that these NF-κB inhibitors may have off-target effects. We therefore used a selective genetic approach to inhibit NF-κB signaling by overexpression of a dominant-negative IκBα (mIκBα). These studies revealed decreased cell growth in only one of five thyroid cancer cell lines (8505C), which occurred through a block in the S-G2/M transition. Resistance to TNFα-induced apoptosis was observed in all cell lines, likely through an NF-κB-dependent mechanism. Inhibition of NF-κB by mIκBα sensitized a subset of cell lines to TNFα-induced apoptosis. Sensitive cell lines displayed sustained activation of the stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK) pathway, defining a potential mechanism of response. Finally, NF-κB inhibition by mIκBα expression differentially reduced thyroid cancer cell invasion in these thyroid cancer cell lines. Sensitive cell lines demonstrated approximately a two-fold decrease in invasion, which was associated with differential expression of MMP-13. MMP-9 was reduced by mIκBα expression in all cell lines tested.

Conclusions

These data indicate that selective inhibition of NF-κB represents an attractive therapeutic target for the treatment of advanced thyroid. However, it is apparent that global regulation of thyroid cancer cell growth and invasion is not achieved by NF-κB signaling alone. Instead, our findings suggest that other important molecular processes play a critical role in defining the extent of NF-κB function within cancer cells.
Study of stability of time-domain features for electromyographic pattern recognition
Authors: Tkach Dennis , Huang He , Kuiken Todd A
Published: May 2010

Background

Significant progress has been made towards the clinical application of human-machine interfaces (HMIs) based on electromyographic (EMG) pattern recognition for various rehabilitation purposes. Making this technology practical and available to patients with motor deficits requires overcoming real-world challenges, such as physical and physiological changes, that result in variations in EMG signals and systems that are unreliable for long-term use. In this study, we aimed to address these challenges by (1) investigating the stability of time-domain EMG features during changes in the EMG signals and (2) identifying the feature sets that would provide the most robust EMG pattern recognition.

Methods

Variations in EMG signals were introduced during physical experiments. We identified three disturbances that commonly affect EMG signals: EMG electrode location shift, variation in muscle contraction effort, and muscle fatigue. The impact of these disturbances on individual features and combined feature sets was quantified by changes in classification performance. The robustness of feature sets was evaluated by a stability index developed in this study.

Results

Muscle fatigue had the smallest effect on the studied EMG features, while electrode location shift and varying effort level significantly reduced the classification accuracy for most of the features. Under these disturbances, the most stable EMG feature set with combination of four features produced at least 16.0% higher classification accuracy than the least stable set. EMG autoregression coefficients and cepstrum coefficients showed the most robust classification performance of all studied time-domain features.

Conclusions

Selecting appropriate EMG feature combinations can overcome the impact of the studied disturbances on EMG pattern classification to a certain extent; however, this simple solution is still inadequate. Stabilizing electrode contact locations and developing effective classifier training strategies are suggested to further improve the robustness of HMIs based on EMG pattern recognition.
Coexistence of mal de Meleda and congenital cataract in a consanguineous Tunisian family: two case reports
Authors: Bchetnia Mbarka , Merdassi Ahlem , Charfeddine Cherine , Mgaieth Fatma , Kassar Selma , Ouechtati Farah , Chouchene Ibtissem , Boussen Hamouda , Mokni Mourad , Osman Amel Dhahri-Ben , Boubaker Med Samir , Abdelhak Sonia , Elmatri Leila
Published: May 2010

Introduction

Mal de Meleda is a rare form of palmoplantar keratoderma, with autosomal recessive transmission. It is characterized by diffuse erythema and hyperkeratosis of the palms and soles. Recently, mutations in the ARS (component B) gene (ARS, MIM: 606119) on chromosome 8q24.3 have been identified in families with this disorder. Congenital cataract is a visual disease that may interfere with sharp imaging of the retina. Mutations in the heat-shock transcription factor 4 gene (HSF4; MIM: 602438) may result in both autosomal dominant and autosomal recessive congenital cataracts.

Case presentation

A Tunisian family with two female siblings aged 45 and 30 years, presented with a clinical association of mal de Meleda and congenital cataract. The two patients exhibited diffuse palmoplantar keratodermas. One of them presented with a total posterior subcapsular cataract and had a best corrected visual acuity at 1/20 in the left eye and with the right eye was only able to count fingers at a distance of one foot. The other woman had a slight posterior subcapsular lenticular opacity and her best corrected visual acuity was 8/10 in the right eye and with her left eye she was only able to count fingers at a distance of one foot. A mutational analysis of their ARS gene revealed the presence of the homozygous missense mutation C99Y and two single nucleotide polymorphisms (-55G>C and -60G>C). The splice mutation (c.1327+4A-G) within intron 12 of the HSF4 gene, which has been previously described in Tunisian families with congenital cataract, was not found in the two probands within this family.

Conclusion

To the best of our knowledge, such original clinical association has not been reported previously. The association of these two autosomal recessive diseases might have occurred in this family due to a high degree of inbreeding. The C99Y mutation may be specific to the Tunisian population as it has been exclusively reported so far in only three Tunisian families with mal de Meleda.
Extracorporeal life support for management of refractory cardiac or respiratory failure: initial experience in a tertiary centre
Authors: Peris Adriano , Cianchi Giovanni , Biondi Simona , Bonizzoli Manuela , Pasquini Andrea , Bonacchi Massimo , Ciapetti Marco , Zagli Giovanni , Bacci Simona , Lazzeri Chiara , Bernardo Pasquale , Mascitelli Erminia , Sani Guido , Gensini Gian Franco
Published: May 2010

Introduction

Extracorporeal Life Support (ECLS) and extracorporeal membrane oxygenation (ECMO) have been indicated as treatment for acute respiratory and/or cardiac failure. Here we describe our first year experience of in-hospital ECLS activity, the operative algorithm and the protocol for centralization of adult patients from district hospitals.

Methods

At a tertiary referral trauma center (Careggi Teaching Hospital, Florence, Italy), an ECLS program was developed from 2008 by the Emergency Department and Heart and Vessel Department ICUs. The ECLS team consists of an intensivist, a cardiac surgeon, a cardiologist and a perfusionist, all trained in ECLS technique. ECMO support was applied in case of severe acute respiratory distress syndrome (ARDS) not responsive to conventional treatments. The use of veno-arterial (V-A) ECLS for cardiac support was reserved for cases of cardiac shock refractory to standard treatment and cardiac arrests not responding to conventional resuscitation.

Results

A total of 21 patients were treated with ECLS during the first year of activity. Among them, 13 received ECMO for ARDS (5 H1N1-virus related), with a 62% survival. In one case of post-traumatic ARDS, V-A ECLS support permitted multiple organ donation after cerebral death was confirmed. Patients treated with V-A ECLS due to cardiogenic shock (N = 4) had a survival rate of 50%. No patients on V-A ECLS support after cardiac arrest survived (N = 4).

Conclusions

In our centre, an ECLS Service was instituted over a relatively limited period of time. A strict collaboration between different specialists can be regarded as a key feature to efficiently implement the process.
UPR-mediated TRIB3 expression correlates with reduced AKT phosphorylation and inability of interleukin 6 to overcome palmitate-induced apoptosis in RINm5F cells
Authors: Nicoletti-Carvalho José Edgar , Araújo Nogueira Tatiane C , Gorjão Renata , Bromati Carla Rodrigues , Yamanaka Tatiana S , Boschero Antonio Carlos , Velloso Licio Augusto , Curi Rui , Anhê Gabriel Forato , Bordin Silvana
Published: May 2010

Unfolded protein response (UPR)-mediated pancreatic β-cell death has been described as a common mechanism by which palmitate (PA) and pro-inflammatory cytokines contribute to the development of diabetes. There are evidences that interleukin 6 (IL6) has a protective action against β-cell death induced by pro-inflammatory cytokines; the effects of IL6 on PA-induced apoptosis have not been investigated yet. In the present study, we have demonstrated that PA selectively disrupts IL6-induced RAC-alpha serine/threonine-protein kinase (AKT) activation without interfering with signal transducer and activator of transcription 3 phosphorylation in RINm5F cells. The inability of IL6 to activate AKT in the presence of PA correlated with an inefficient protection against PA-induced apoptosis. In contrast to PA, IL6 efficiently reduced apoptosis induced by pro-inflammatory cytokines. In addition, we have demonstrated that IL6 is unable to overcome PA-stimulated UPR, as assessed by activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP) expression, X-box binding protein-1 gene mRNA splicing, and pancreatic eukaryotic initiation factor-2α kinase phosphorylation, whereas no significant induction of UPR by pro-inflammatory cytokines was detected. This unconditional stimulation of UPR and apoptosis by PA was accompanied by the stimulation of CHOP and tribble3 (TRIB3) expression, irrespective of the presence of IL6. These findings suggest that IL6 is unable to protect pancreatic β-cells from PA-induced apoptosis because it does not repress UPR activation. In this way, CHOP and ATF4 might mediate PA-induced TRIB3 expression and, by extension, the suppression of IL6 activation of pro-survival kinase AKT.
Extracellular-regulated kinase and p38 mitogen-activated protein kinases are involved in the antiapoptotic action of 17β-estradiol in skeletal muscle cells
Authors: Ronda Ana Carolina , Vasconsuelo Andrea , Boland Ricardo
Published: May 2010

17β-Estradiol (E2) stimulates the mitogen-activated protein kinases (MAPKs) in various cellular types. We have shown that the hormone activates extracellular-regulated kinase (ERK) and p38 MAPK in skeletal muscle cells. However, the functions of MAPK modulation by the estrogen in muscle cells have not been studied yet. We have recently reported antiapoptotic actions of E2 in C2C12 cells. Here, the role of MAPKs mediating the hormone effect in muscle cells was investigated. The results showed that cells exposed to 0.5 mM hydrogen peroxide (H2O2) presented cytoskeleton disorganization, mitochondrial redistribution, and picnotic/fragmented nuclei. Pretreatment with 10−8 M E2 prevented these morphological apoptotic characteristics, except in the presence of ERK or p38 MAPK inhibitors, U0126 and SB203580 respectively. Mitochondrial membrane integrity was also studied. Preincubation of cultures with 10−8 M E2 abrogated H2O2 effects such as Janus Green oxidation, presence of cytochrome c oxidase activity in the cytoplasm, and SMAC/DIABLO release from mitochondria. When MAPKs were inhibited, the hormone could not prevent mitochondrial membrane damage exerted by oxidative stress. Blocking experiments with small interfering RNAs confirmed that both ERK and p38 MAPKs mediate the antiapoptotic effects of the hormone at the mitochondrial level. Further, some of the molecular mechanisms involved were also investigated. Thus, E2 was able to induce AKT (Ser473) and BAD (Ser112) phosphorylation in C2C12 cells in the absence or in the presence of H2O2 but not when the cultures were incubated with H2O2 and MAPK inhibitors. Altogether, these results show that E2 exerts a survival action in skeletal muscle cells involving ERK and p38 MAPK activation.
Recovery of nitrogen from saponification wastewater by struvite precipitation
Authors: Huang Haiming , Xiao Xianming , Yang Liping , Yan Bo
Published: May 2010

In general, saponification wastewater produced from the separation process of rare-earth elements contains high ammonium concentration. In this study, a series of experiments were conducted to investigate the parameters to enhance the struvite precipitation potential for ammonium removal from the wastewater having an ammonium concentration of 4,100 mg/L. Experimental results showed that increasing the dose and grain size of pre-formed struvite, which was added as the seeding material in struvite reaction, could increase ammonium removal. The removal efficiency increased 7.6% when the dose of pre-formed struvite with crystal grain size range of 0.098–0.150 mm increased from 0 g/L to 60 g/L. Additionally, struvite precipitation was tested with the intermittent addition of magnesium and phosphate to utilize the struvite crystals formed during the reaction process as the seeding material for the subsequent reaction. The results revealed that intermittently adding magnesium 7 times effectively enhanced ammonium removal by around 8%, which was equivalent to that of using pre-formed struvite as the seeding material. Furthermore, the chemical composition of the struvite recovered with intermittent addition of magnesium was characterized, showing the struvite could be used as fertilizer. An economic evaluation indicated that intermittent addition of magnesium 7 times can save 13.4% cost for recovering per kg NH4+ compared to that of bulk addition.
Organic carbon effect on nitrifying bacteria in a mixed culture
Authors: Racz L. , Datta T. , Goel R. K.
Published: May 2010

This study investigated the effect of organic carbon source on ammonia oxidizing community in single sludge laboratory scale sequencing batch reactors (SBR). Two sequencing batch reactors performing simultaneous carbon oxidation and nitrification were operated. Operationally and functionally, these two reactors were identical, except that one reactor was fed peptone and sodium acetate, and the other was fed glucose and sodium acetate as external organic carbon sources. The peptone-fed reactor had 98.1±1.84% COD removal and 97.3±6.69% NH3-N oxidation. The glucose-fed reactor had 99.1±1.29% COD removal and 99.4±0.76% NH3-N oxidation. The reactor fed with peptone, a complex organic carbon source comprised of enzymatic digests of animal proteins, had greater diversity in both the heterotrophic bacterial community and the ammonia oxidizing bacteria community than in the reactor fed with glucose, a simple sugar as evidenced by automated ribosomal intergenic spacer analysis (ARISA) and terminal restriction fragment length polymorphism (TRFLP) experiments respectively.
Mathematical model of biofilm induced calcite precipitation
Authors: Zhang T. , Klapper I.
Published: May 2010

Microbially modulated carbonate precipitation is a fundamentally important phenomenon of both engineered and natural environments. In this paper, we propose a mixture model for biofilm induced calcite precipitation. The model consists of three phases – calcite, biofilm and solvent – which satisfy conservation of mass and momentum laws with addition of a free energy of mixing. The model also accounts for chemistry, mechanics, thermodynamics, fluid and electrodiffusion transport effects. Numerical simulations qualitatively capturing the dynamics of this process and revealing effects of kinetic parameters and external flow conditions are presented.
Impact of pollution and seasonal changes on microbial community structure in surface water
Authors: Mlejnková H. , Sovová K.
Published: May 2010

We studied the differences in a microbial community structure with respect to the water pollution level and seasonal changes. The determination of phylogenetic groups of Bacteria and Archaea was done using fluorescent in situ hybridization (FISH). The total number of microorganisms was determined by direct counting of DAPI (4′,6-diamidino-2-phenylindole) stained samples using a fluorescence microscope. Our results showed that the microbial community structure was significantly dependent on the level of water pollution, both in absolute microbial counts and in relative abundance of phylogenetic groups. For surface water with anthropogenic pollution, the microbial community with significant proportion of Betaproteobacteria and Cytophaga-Flavobacterium was characteristic. Gammaproteobacteria were significant in municipal waste water. In microbial communities with low numbers of microorganisms (e.g. non-polluted water and some industrial waste water) represented the significant component groups Alphaproteobacteria and Archaea. The impact of seasonal changes on the microbial distribution was not significant.