bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimizing Recombinant Protein Production in the Escherichia coli Periplasm Alleviates Stress
Authors: Baumgarten Thomas , Ytterberg A. Jimmy , Zubarev Roman A. , de Gier Jan-Willem 
Published: April 2018

ABSTRACTInEscherichia coli, many recombinant proteins are produced in the periplasm. To direct these proteins to this compartment, they are equipped with an N-terminal signal sequence so that they can traverse the cytoplasmic membrane via the protein-conducting Sec translocon. Recently, using the single-chain variable antibody fragment BL1, we have shown that harmonizing the target gene expression intensity with the Sec translocon capacity can be used to improve the production yields of a recombinant protein in the periplasm. Here, we have studied the consequences of improving the production of BL1 in the periplasm by using a proteomics approach. When the target gene expression intensity is not harmonized with the Sec translocon capacity, the impaired translocation of secretory proteins, protein misfolding/aggregation in the cytoplasm, and an inefficient energy metabolism result in poor growth and low protein production yields. The harmonization of the target gene expression intensity with the Sec translocon capacity results in normal growth, enhanced protein production yields, and, surprisingly, a composition of the proteome that is—besides the produced target—the same as that of cells with an empty expression vector. Thus, the single-chain variable antibody fragment BL1 can be efficiently produced in the periplasm without causing any notable detrimental effects to the production host. Finally, we show that under the optimized conditions, a small fraction of the target protein is released into the extracellular milieu via outer membrane vesicles. We envisage that our observations can be used to design strategies to further improve the production of secretory recombinant proteins inE. coli.IMPORTANCEThe bacteriumEscherichia coliis widely used to produce recombinant proteins. Usually, trial-and-error-based screening approaches are used to identify conditions that lead to high recombinant protein production yields. Here, for the production of an antibody fragment in the periplasm ofE. coli, we show that an optimization of its production is accompanied by the alleviation of stress. This indicates that the monitoring of stress responses could be used to facilitate enhanced recombinant protein production yields.
Genome Sequence of a Heterotrophic Nitrifier and Aerobic Denitrifier, Paracoccus denitrificans Strain ISTOD1, Isolated from Wastewater
Authors: Medhi Kristina , Mishra Arti , Thakur Indu Shekhar 
Published: April 2018

ABSTRACT

We report here the draft genome sequence of
Paracoccus denitrificans
strain ISTOD1 of 4.9 Mb, isolated from wastewater. It has been identified as a heterotrophic nitrifying and aerobic denitrifying bacterium. Genomic analysis revealed genes related to nitrogen and phosphorus removal, showing that the strain holds potential for bioremediation and biorefinery uses.
Genome Sequences of Five Mycobacterium bovis Strains Isolated from Farmed Animals and Wildlife in Canada
Authors: Andrievskaia Olga , Duceppe Marc-Olivier , Lloyd Dara 
Published: April 2018

ABSTRACT

Mycobacterium bovis
is the causative agent of bovine tuberculosis, an infectious disease that affects both animals and humans and thus presents a risk to public health and the livestock industry. Here, we report the genome sequences of five
Mycobacterium bovis
strains that represent major genotype clusters observed in farmed animals and wildlife in Canada.
Draft Genome Sequence of Janthinobacterium sp. Strain ROICE36, a Putative Secondary Metabolite-Synthesizing Bacterium Isolated from Antarctic Snow
Authors: Chiriac Cecilia , Baricz Andreea , Coman Cristian 
Published: April 2018

ABSTRACT

The draft genome assembly of
Janthinobacterium
sp. strain ROICE36 has 207 contigs, with a total genome size of 5,977,006 bp and a G+C content of 62%. Preliminary genome analysis identified 5,363 protein-coding genes and a total of 7 secondary metabolic gene clusters (encoding bacteriocins, nonribosomal peptide-synthetase [NRPS], terpene, hserlactone, and other ketide synthases).
Actigraphy assessment of sleep quality among patients with acute myeloid leukaemia during induction chemotherapy
Authors: Yang Chi-Fu Jeffrey , Aibel Kelli , Meyerhoff Ryan , Wang Frances , Harpole David , Abernethy Amy P , LeBlanc Thomas W 
Published: April 2018

ObjectivesPatients receiving induction chemotherapy for acute myeloid leukaemia (AML) anecdotally describe poor sleep, but sleep disturbances have not been well-characterised in this population. We aimed to test the feasibility of measuring sleep quality in AML inpatients using a wearable actigraphy device.MethodsUsing the Actigraph GT3X ‘watch’, we assessed the total sleep time, sleep onset latency, wake after sleep onset, number of awakenings after sleep onset and sleep eﬃciency for inpatients with AML receiving induction chemotherapy. We assessed patient self-reported sleep quality using the Pittsburgh Sleep Quality Index (PSQI).ResultsOf the 12 patients enrolled, 11 completed all actigraphy and PSQI assessments, demonstrating feasibility. Patients wore the Actigraph device for a mean (SD) of 15.92 (8.3) days, and actigraphy measures suggested poor sleep. Patients had a median average awakening length of 6.92 min, a median number of awakenings after sleep onset of 4 and a median sleep onset latency of 10.8 min. Actual median sleep efficiency (0.91) was high, suggesting that patients’ poor sleep was not due to insomnia but perhaps due to interruptions, such as administration of medications, lab draws and vital sign measurements.ConclusionsCollection of sleep quality data among inpatients with AML via a wearable actigraphy device is feasible. AML inpatients appear to have poor sleep quality and quantity, suggesting that sleep issues represent an area of unmet supportive care needs in AML. Further research in this areas is needed to inform the development of interventions to improve sleep duration and quality in hospitalised patients with AML.
Multi-Sequential Word Relations
Authors: Jecker Ismaël , Filiot Emmanuel 
Published: April 2018

Rational relations are binary relations of finite words that are realised by non-deterministic finite state transducers (NFT). A multi-sequential relation is a rational relation which is equal to a finite union of (graphs) of partial sequential functions, i.e. functions realised by input-deterministic transducers. The particular case of multi-sequential functions was studied by Choffrut and Schützenberger who proved that given a rational function (as a transducer), it is decidable whether it is multi-sequential. Their procedure is based on an effective characterisation of unambiguous transducers that do not define multi-sequential functions, that we call the fork property. In this paper, we show that the fork property also characterises the class of transducers that do not define multi-sequential relations. Moreover, we prove that the fork property can be decided in PTime. This leads to a PTime procedure which, given a transducer, decides whether it defines a multi-sequential relation.
Action potential propagation recorded from single axonal arbors using multielectrode arrays
Authors: Tovar Kenneth R. , Bridges Daniel C. , Wu Bian , Randall Connor , Audouard Morgane , Jang Jiwon , Hansma Paul K. , Kosik Kenneth S. 
Published: April 2018

We report the presence of co-occurring extracellular action potentials (eAPs) from cultured mouse hippocampal neurons among groups of planar electrodes on multielectrode arrays (MEAs). The invariant sequences of eAPs among coactive electrode groups, repeated co-occurrences, and short interelectrode latencies are consistent with action potential propagation in unmyelinated axons. Repeated eAP codetection by multiple electrodes was widespread in all our data records. Codetection of eAPs confirms they result from the same neuron and allows these eAPs to be isolated from all other spikes independently of spike sorting algorithms. We averaged co-occurring events and revealed additional electrodes with eAPs that would otherwise be below detection threshold. We used these eAP cohorts to explore the temperature sensitivity of action potential propagation and the relationship between voltage-gated sodium channel density and propagation velocity. The sequence of eAPs among coactive electrodes “fingerprints” neurons giving rise to these events and identifies them within neuronal ensembles. We used this property and the noninvasive nature of extracellular recording to monitor changes in excitability at multiple points in single axonal arbors simultaneously over several hours, demonstrating independence of axonal segments. Over several weeks, we recorded changes in interelectrode propagation latencies and ongoing changes in excitability in different regions of single axonal arbors. Our work illustrates how repeated eAP co-occurrences can be used to extract physiological data from single axons with low-density MEAs. However, repeated eAP co-occurrences lead to oversampling spikes from single neurons and thus can confound traditional spike-train analysis. NEW & NOTEWORTHY We studied action potential propagation in single axons using low-density multielectrode arrays. We unambiguously identified the neuronal sources of propagating action potentials and recorded extracellular action potentials from several positions within single axonal arbors. We found a surprisingly high density of axonal voltage-gated sodium channels responsible for a high propagation safety factor. Our experiments also demonstrate that excitability in different segments of single axons is regulated independently on timescales from hours to weeks.
Somatosensory electrical stimulation improves skill acquisition, consolidation, and transfer by increasing sensorimotor activity and connectivity
Authors: Veldman Menno P. , Maurits Natasha M. , Zijdewind Inge , Maffiuletti Nicola A. , van Middelkoop Stella , Mizelle J. Chris , Hortobágyi Tibor 
Published: April 2018

The interaction between the somatosensory and motor systems is important for normal human motor function and learning. Enhancing somatosensory input using somatosensory electrical stimulation (SES) can increase motor performance, but the neuronal mechanisms underlying these effects are largely unknown. With EEG, we examined whether skill acquisition, consolidation, and interlimb transfer after SES was related to increased activity in sensorimotor regions, as assessed by the N30 somatosensory evoked potential or rather increased connectivity between these regions, as assessed by the phase slope index (PSI). Right- and left-hand motor performance and EEG measures were taken before, immediately after, and 24 h ( day 2) after either SES ( n = 12; 5 men) or Control ( n = 12; 5 men). The results showed skill acquisition and consolidation in the stimulated right hand immediately after SES (6%) and on day 2 (9%) and interlimb transfer to the nonstimulated left hand on day 2 relative to Control (8%, all P < 0.05). Increases in N30 amplitudes correlated with skill acquisition while PSI from electrodes that represent the posterior parietal and primary somatosensory cortex to the electrode representing the primary motor cortex correlated with skill consolidation. In contrast, interlimb transfer did not correlate with the EEG-derived neurophysiological estimates obtained in the present study, which may indicate the involvement of subcortical structures in interlimb transfer after SES. In conclusion, weak peripheral somatosensory inputs in the form of SES improve skill acquisition, consolidation, and interlimb transfer that coincide with different cortical adaptations, including enhanced N30 amplitudes and PSI.NEW & NOTEWORTHY The relationship between adaptations in synaptic plasticity and motor learning following somatosensory electrical stimulation (SES) is incompletely understood. Here, we used for the first time a multifactorial approach that examined skill acquisition, consolidation, and interlimb transfer following 20 min of SES. In addition, we quantified sensorimotor integration and the magnitude and direction of connectivity with EEG. Following artificial electrical stimulation, increases in sensorimotor integration and connectivity were found to correlate with skill acquisition and consolidation, respectively.
Methyl Chavicol and Its Synthetic Analogue as Possible Antioxidant and Antilipase Agents Based on the In Vitro and In Silico Assays
Authors: Santos Bruna Celeida Silva , Pires Andressa Soares , Yamamoto Célia Hitomi , Couri Mara Rubia Costa , Taranto Alex Gutterres , Alves Maria Silvana , Araújo Ana Lúcia dos Santos de Matos , de Sousa Orlando Vieira 
Published: April 2018

This study investigated the in vitro and in silico biological properties of the methyl chavicol (MC) and its analogue 2‐[(4‐methoxyphenyl)methyl]oxirane (MPMO), emphasizing the antioxidant and antilipase effects. MPMO was synthesized from MC that reacted with meta‐chloroperbenzoic acid and, after separation and purification, was identified by 1H and 13C NMR and GC‐MS. The antioxidant activity was investigated by DPPH, cooxidation β‐carotene/linoleic acid, and thiobarbituric acid assays. With the use of colorimetric determination, the antilipase effect on the pancreatic lipase was tested, while the molecular interaction profiles were evaluated by docking molecular study. MC (IC50 = 312.50 ± 2.28 μg/mL) and MPMO (IC50 = 8.29 ± 0.80 μg/mL) inhibited the DPPH free radical. The inhibition of lipid peroxidation (%) was 73.08 ± 4.79 and 36.16 ± 4.11 to MC and MPMO, respectively. The malonaldehyde content was significantly reduced in the presence of MC and MPMO. MC and MPMO inhibited the pancreatic lipase in 58.12 and 26.93%, respectively. MC and MPMO (−6.1 kcal·mol−1) produced a binding affinity value lower than did diundecylphosphatidylcholine (−5.6 kcal·mol−1). These findings show that MC and MPMO present antioxidant and antilipase activities, which may be promising molecular targets for the treatment of diseases associated with oxidative damage and lipid metabolism.
Effects of Impella on Coronary Perfusion in Patients With Critical Coronary Artery Stenosis
Authors: Alqarqaz Mohammad , Basir Mir , Alaswad Khaldoon , O’Neill William 
Published: April 2018

Background—
Mechanical circulatory support devices are used to maintain hemodynamic stability during high-risk percutaneous coronary interventions. Little is known on the effects of such devices on coronary hemodynamics in patients with significant coronary stenosis. We sought to investigate whether mechanical circulatory support in the form of Impella (Abiomed Inc, Danvers, MA) can improve coronary hemodynamics in the presence of a critical coronary stenosis.

Methods and Results—

We examined coronary perfusion pressures and coronary pressure distal to a critical stenosis using a coronary pressure wire in 11 patients (12 coronary lesions) undergoing high-risk percutaneous coronary interventions with the use of mechanical circulatory support. Systemic, ventricular, and coronary hemodynamics were obtained at both minimum and maximum support levels before high-risk percutaneous coronary interventions. All patients had obstructive lesions with angiographically estimated diameter stenosis between 70% and 99% and distal coronary artery pressure to aortic pressure ratios between 0.44 and 0.88. When compared with minimum support, maximum support resulted in a decrease in the left ventricular end-diastolic pressure (27.3±8.6 versus 21.5±5.2 mm Hg;
P
=0.002) and increases in the mean systemic blood pressure (77.6±13.5 versus 88.2±12.2 mm Hg;
P
<0.001) and mean distal coronary pressure (51.8±20.2 versus 60.8±18.1 mm Hg;
P
<0.001). Effective coronary perfusion pressure (mean aortic pressure–left ventricular end-diastolic pressure) significantly increased with maximum support (49.8±15.7 versus 67.2±13.6 mm Hg;
P
<0.001). Diastolic perfusion pressure (diastolic blood pressure–left ventricular end-diastolic pressure) also significantly increased with maximum support (32.9±13.4 versus 52.0±11.6 mm Hg;
P
<0.001).

Conclusions—
Mechanical circulatory support with Impella can improve distal coronary pressure and coronary perfusion pressures in the presence of critical coronary stenosis.
Using the Gradient Boosting Decision Tree to Improve the Delineation of Hourly Rain Areas during the Summer from Advanced Himawari Imager Data
Authors: Ma Liang , Zhang Guoping , Lu Er 
Published: April 2018

AbstractA new classification scheme based on the gradient boosting decision tree (GBDT) algorithm is developed to improve the accuracy of rain area delineation for daytime, twilight, and nighttime modules using Advanced Himawari Imager on board Himawari-8 (AHI-8) geostationary satellite data and the U.S. Geological Survey digital elevation model data. The GBDT algorithm is able to efficiently manage the nonlinear relationships among high-dimensional data without being affected by overfitting problems. The new delineation module utilizes several features related to the physical variables, including cloud-top heights, cloud-top temperatures, cloud water paths, cloud phases, water vapor, temporal changes, and orographic variations. The scheme procedure is as follows. First, we perform extensive experiments to optimize the module parameters such that the equitable threat score (ETS) reaches its maximum value. Then, the GBDT-based modules are trained and classified with the optimum parameters. Finally, validation datasets are applied to test the true performance of the GBDT-based modules. The agreement between the estimations and observations of the ground-based rain gauges is verified. Results show that the ETS values of the GBDT-based modules are 0.42 for the daytime, 0.30 for the twilight period, and 0.32 for the nighttime. The cloud water path and cloud phase features make the most significant contributions to the modules. Comparisons drawn with the two probability-related methods show that our new scheme presents great advantages in terms of statistical scores on the overall performance.
Subseasonal Forecasts of Convectively Coupled Equatorial Waves and the MJO: Activity and Predictive Skill
Authors: Janiga Matthew A. , J. Schreck Carl , Ridout James A. , Flatau Maria , Barton Neil P. , Metzger E. Joseph , Reynolds Carolyn A. 
Published: April 2018

AbstractIn this study, the contribution of low-frequency (&gt;100 days), Madden–Julian oscillation (MJO), and convectively coupled equatorial wave (CCEW) variability to the skill in predicting convection and winds in the tropics at weeks 1–3 is examined. We use subseasonal forecasts from the Navy Earth System Model (NESM); NCEP Climate Forecast System, version 2 (CFSv2); and ECMWF initialized in boreal summer 1999–2015. A technique for performing wavenumber–frequency filtering on subseasonal forecasts is introduced and applied to these datasets. This approach is better able to isolate regional variations in MJO forecast skill than traditional global MJO indices. Biases in the mean state and in the activity of the MJO and CCEWs are smallest in the ECMWF model. The NESM overestimates cloud cover as well as MJO, equatorial Rossby, and mixed Rossby–gravity/tropical depression activity over the west Pacific. The CFSv2 underestimates convectively coupled Kelvin wave activity. The predictive skill of the models at weeks 1–3 is examined by decomposing the forecasts into wavenumber–frequency signals to determine the modes of variability that contribute to forecast skill. All three models have a similar ability to simulate low-frequency variability but large differences in MJO skill are observed. The skill of the NESM and ECMWF model in simulating MJO-related OLR signals at week 2 is greatest over two regions of high MJO activity, the equatorial Indian Ocean and Maritime Continent, and the east Pacific. The MJO in the CFSv2 is too slow and too weak, which results in lower MJO skill in these regions.
Characteristics and efficacy of digital health education: An overview of systematic reviews
Authors: McCall Marcy , Spencer Elizabeth , Owen Helen , Roberts Nia , Heneghan Carl 
Published: April 2018

Objective: The primary aim of this overview was to synthesise results from studies including digital education and its effect on knowledge or learning outcomes, student satisfaction, student enrolment, attendance rate, course completion rate, clinical practice, health outcomes for patients and cost-effectiveness in health-care education. A secondary aim was to report on successful instructional design strategies, and barriers or contextual factors influencing the effectiveness of online learning course delivery in healthcare education. Method: We conducted an overview of systematic reviews (SRs) for digital education interventions delivered to health-care students and practitioners. Results: We scanned 848 titles, reviewed 247 abstracts and assessed 49 full-text articles against pre-determined inclusion and exclusion criteria. This overview includes data collected from 31,730 participants across 16 SRs. The quality of evidence included in the SRs ranged from very low ( n = 2), low ( n = 6) to moderate ( n = 8). The best available SRs were of moderate quality (7.4 of 11 AMSTAR). SR authors did not report other teaching methods as being superior to digital learning. In most cases ( n = 9), digital education when used in addition to traditional methods augmented knowledge acquisition. Other SRs ( n = 7) did not show statistically significant differences across interventions including digital education as a replacement, or additive resource to traditional intervention. Conclusion: Student enrolment, attendance rates, course completion rates, cost-effectiveness and changes in clinical outcomes for patients are underreported in the existing evidence. Although the quality and quantity of data are limited, evidence-based instructional design for digital education is becoming more possible, especially as educators establish learning activities that track to learning objectives for knowledge acquisition in health care.
Independent Coactors May Improve Performance and Lower Workload: Viewing Vigilance Under Social Facilitation
Authors: Claypoole Victoria L. , Szalma James L. 
Published: April 2018

Objective: The purpose of the present study was to examine the effects of an independent coactor on vigilance task performance. It was hypothesized that the presence of an independent coactor would improve performance in terms of the proportion of false alarms while also increasing perceived workload and stress. Background: Vigilance, or the ability to maintain attention for extended periods, is of great interest to human factors psychologists. Substantial work has focused on improving vigilance task performance, typically through motivational interventions. Of interest to vigilance researchers is the application of social facilitation as a means of enhancing vigilance. Social facilitation seeks to explain how social presence may improve performance. Method: A total of 100 participants completed a 24-min vigil either alone or in the presence of an independent (confederate) coactor. Participants completed measures of perceived workload and stress. Results: The results indicated that performance (i.e., proportion of false alarms) was improved for those who completed the vigil in the presence of an independent coactor. Interestingly, perceived workload was actually lower for those who completed the vigil in the presence of an independent coactor, although perceived stress was not affected by the manipulation. Conclusion: Authors of future research should extend these findings to other forms of social facilitation and examine vigilance task performance in social contexts in order to determine the utility of social presence for improving vigilance. Application: The use of coactors may be an avenue for organizations to consider utilizing to improve performance because of its relative cost-effectiveness and easy implementation.