bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular motion regulates the activity of the Mitochondrial Serine Protease HtrA2
Authors: Merski Matthew , Moreira Cátia , Abreu Rui MV , Ramos Maria João , Fernandes Pedro A , Martins L Miguel , Pereira Pedro José Barbosa , Macedo-Ribeiro Sandra 
Published: October 2017

AbstractHtrA2 (high-temperature requirement 2) is a human mitochondrial protease that has a role in apoptosis and Parkinson’s disease. The structure of HtrA2 with an intact catalytic triad was determined, revealing a conformational change in the active site loops, involving mainly the regulatory LD loop, which resulted in burial of the catalytic serine relative to the previously reported structure of the proteolytically inactive mutant. Mutations in the loops surrounding the active site that significantly restricted their mobility, reduced proteolytic activity both in vitro and in cells, suggesting that regulation of HtrA2 activity cannot be explained by a simple transition to an activated conformational state with enhanced active site accessibility. Manipulation of solvent viscosity highlighted an unusual bi-phasic behavior of the enzymatic activity, which together with MD calculations supports the importance of motion in the regulation of the activity of HtrA2. HtrA2 is an unusually thermostable enzyme (TM=97.3 °C), a trait often associated with structural rigidity, not dynamic motion. We suggest that this thermostability functions to provide a stable scaffold for the observed loop motions, allowing them a relatively free conformational search within a rather restricted volume.
Zika virus infection dysregulates human neural stem cell growth and inhibits differentiation into neuroprogenitor cells
Authors: Devhare Pradip , Meyer Keith , Steele Robert , Ray Ratna B , Ray Ranjit 
Published: October 2017

AbstractThe current outbreak of Zika virus-associated diseases in South America and its threat to spread to other parts of the world has emerged as a global health emergency. A strong link between Zika virus and microcephaly exists, and the potential mechanisms associated with microcephaly are under intense investigation. In this study, we evaluated the effect of Zika virus infection of Asian and African lineages (PRVABC59 and MR766) in human neural stem cells (hNSCs). These two Zika virus strains displayed distinct infection pattern and growth rates in hNSCs. Zika virus MR766 strain increased serine 139 phosphorylation of histone H2AX (γH2AX), a known early cellular response proteins to DNA damage. On the other hand, PRVABC59 strain upregulated serine 15 phosphorylation of p53, p21 and PUMA expression. MR766-infected cells displayed poly (ADP-ribose) polymerase (PARP) and caspase-3 cleavage. Interestingly, infection of hNSCs by both strains of Zika virus for 24 h, followed by incubation in astrocyte differentiation medium, induced rounding and cell death. However, astrocytes generated from hNSCs by incubation in differentiation medium when infected with Zika virus displayed minimal cytopathic effect at an early time point. Infected hNSCs incubated in astrocyte differentiating medium displayed PARP cleavage within 24–36 h. Together, these results showed that two distinct strains of Zika virus potentiate hNSC growth inhibition by different mechanisms, but both viruses strongly induce death in early differentiating neuroprogenitor cells even at a very low multiplicity of infection. Our observations demonstrate further mechanistic insights for impaired neuronal homeostasis during active Zika virus infection.
New insights into the impacts of suspended particulate matter on phytoplankton density in a tributary of the Three Gorges Reservoir, China
Authors: He Qiang , Qiu Yixi , Liu Haohang , Sun Xingfu , Kang Li , Cao Li , Li Hong , Ai Hainan 
Published: October 2017

AbstractPhytoplankton density can be influenced by a wide range of factors whereas the role of suspended particulate matter (SPM) are not clear in river that annually subjected to hydrodynamics shift. Here, spatial-temporal variation of environmental parameters and phytoplankton density were studied from January 2013 to December 2014 in Yulin River, a tributary of the Three Gorges Reservoir, China. Laboratory experiments were conducted to elucidate the key parameter and interpret how it impacted phytoplankton density. SPM is negatively correlated with phytoplankton density. Despite SPM in Yulin River revealed weaker NH3-N, NO3-N and PO4-P adsorption capabilities in comparison to that in other aquatic ecosystems, increase of water velocity from 0.1 to 0.8 m/s led to approximately 6.8-times increase of light attenuation rate. In experiments evaluating the aggregation of Chlorella pyrenoidosa upon SPM, floc size showed 7.4 to 22% fold increase compared to the SPM or algae itself, which was due to the interaction between SPM and phytoplankton extracellular polymeric substances. Our results suggest that SPM could contribute to the variation of phytoplankton density through the integrated process including light attenuation, nutrient adsorption and algae aggregation. This is the first evaluation of the multiple processes underlying the impact of SPM on phytoplankton.
Therapeutic potential of Bifidobacterium breve strain A1 for preventing cognitive impairment in Alzheimer’s disease
Authors: Kobayashi Yodai , Sugahara Hirosuke , Shimada Kousuke , Mitsuyama Eri , Kuhara Tetsuya , Yasuoka Akihito , Kondo Takashi , Abe Keiko , Xiao Jin-zhong 
Published: October 2017

AbstractIt has previously been shown that the consumption of probiotics may have beneficial effects not only on peripheral tissues but also on the central nervous system and behavior via the microbiota–gut–brain axis, raising the possibility that treatment with probiotics could be an effective therapeutic strategy for managing neurodegenerative disorders. In this study, we investigated the effects of oral administration ofBifidobacterium brevestrain A1 (B. breveA1) on behavior and physiological processes in Alzheimer’s disease (AD) model mice. We found that administration ofB. breveA1 to AD mice reversed the impairment of alternation behavior in a Y maze test and the reduced latency time in a passive avoidance test, indicating that it prevented cognitive dysfunction. We also demonstrated that non-viable components of the bacterium or its metabolite acetate partially ameliorated the cognitive decline observed in AD mice. Gene profiling analysis revealed that the consumption ofB. breveA1 suppressed the hippocampal expressions of inflammation and immune-reactive genes that are induced by amyloid-β. Together, these findings suggest thatB. breveA1 has therapeutic potential for preventing cognitive impairment in AD.
Long-term toxicity of ZnO nanoparticles to Scenedesmus rubescens cultivated in different media
Authors: Aravantinou Andriana F. , Andreou Fytoula , Manariotis Ioannis D. 
Published: October 2017

AbstractThe aim of this work was to investigate the long-term toxic effect of zinc oxide (ZnO) nanoparticles (NPs) on freshwater microalgae, combined with the nutrient consumption in the culture. For this purpose, two common microalgae media (Blue-Green 11, BG-11, and Bold’s Basal Medium, BBM) were used. Scenedesmus rubescens was used as freshwater microalgae model species and was exposed to ZnO NPs at different concentrations (0.081 to 810 mg/L) for a period up to 28 d. The experimental results revealed that microalgae growth was affected by the time of exposure and the NPs concentrations, but mainly the culture medium used. Differences in microalgae growth rates were observed and attributed to the selected culture medium. The toxic effect of ZnO NPs was higher on microalgae cultured in modified BG-11 compared to BBM, despite the fact that S. rubescens exhibited higher growth rate in modified BG-11 without the exposure of ZnO NPs.
Prediction of Deterministic All-Optical Switching of Ferromagnetic Thin Film by Ultrafast Optothermal and Optomagnetic Couplings
Authors: Du Zhidong , Chen Chen , Cheng Feng , Liu Yongmin , Pan Liang 
Published: October 2017

AbstractAll-optical switching (AOS) of magnetization induced by ultrafast laser pulses is fundamentally interesting and promises unprecedented speed for magnetic data storage that is three orders of magnitudes faster than the current techniques. For ferrimagnetic material, the AOS is attributed to magnetic circular dichroism and angular momentum transfer between sublattices. Recently, ferromagnetic material is demonstrated in AOS under multiple pulses. Since the magnetic field needed to flip the ferromagnetic magnetization within femtosecond timescale is unphysically high, some theories hypothesized that there exists a prolonged magnetic field beyond the pulse duration in the switching process. This is intuitively inconsistent with the phenomenological explanation based on the light-induced magnetic field arising from the inverse Faraday effect (IFE). Here, we numerically study the AOS process and provide new insights into the long-standing paradox of the duration of the induced magnetic field. We show that the prolonged magnetic field duration originates from the ultrafast optothermal and optomagnetic coupling. Moreover, we numerically studied both single- and multiple-pulse AOS under different coupling strength between spins and the thermal bath in the macroscopic Fockker-Planck and Landau-Lifshitz-Bloch model. This numerical model may provide a guide to find suitable ferromagnetic materials for AOS.
A Machine Learning Assisted, Label-free, Non-invasive Approach for Somatic Reprogramming in Induced Pluripotent Stem Cell Colony Formation Detection and Prediction
Authors: Fan Ke , Zhang Sheng , Zhang Ying , Lu Jun , Holcombe Mike , Zhang Xiao 
Published: October 2017

AbstractDuring cellular reprogramming, the mesenchymal-to-epithelial transition is accompanied by changes in morphology, which occur prior to iPSC colony formation. The current approach for detecting morphological changes associated with reprogramming purely relies on human experiences, which involve intensive amounts of upfront training, human error with limited quality control and batch-to-batch variations. Here, we report a time-lapse-based bright-field imaging analysis system that allows us to implement a label-free, non-invasive approach to measure morphological dynamics. To automatically analyse and determine iPSC colony formation, a machine learning-based classification, segmentation, and statistical modelling system was developed to guide colony selection. The system can detect and monitor the earliest cellular texture changes after the induction of reprogramming in human somatic cells on day 7 from the 20–24 day process. Moreover, after determining the reprogramming process and iPSC colony formation quantitatively, a mathematical model was developed to statistically predict the best iPSC selection phase independent of any other resources. All the computational detection and prediction experiments were evaluated using a validation dataset, and biological verification was performed. These algorithm-detected colonies show no significant differences (Pearson Coefficient) in terms of their biological features compared to the manually processed colonies using standard molecular approaches.
Hetero-oligomer of dynamin-related proteins participates in the fission of highly divergent mitochondria from Entamoeba histolytica
Authors: Makiuchi Takashi , Santos Herbert J. , Tachibana Hiroshi , Nozaki Tomoyoshi 
Published: October 2017

AbstractEntamoeba histolytica is an anaerobic parasitic protist and possesses mitosomes, one of the most highly divergent mitochondrion-related organelles (MROs). Although unique metabolism and protein/metabolite transport machinery have been demonstrated in Entamoeba mitosomes, the mechanism of mitosomal fusion and fission remains to be elucidated. In this study, we demonstrate that two dynamin-related proteins (DRPs) are cooperatively involved in the fission of Entamoeba mitosomes. Expression of a dominant negative form of EhDrpA and EhDrpB, and alternatively, repression of gene expression of EhDrpA and EhDrpB genes, caused elongation of mitosomes, reflecting inhibition of mitosomal fission. Moreover, EhDrpA and EhDrpB formed an unprecedented hetero-oligomeric complex with an approximate 1:2 to 1:3 ratio, suggesting that the observed elongation of mitosomes is likely caused by the disruption and instability of the complex caused by an imbalance in the two DRPs. Altogether, this is the first report of a hetero-oligomeric DRP complex which participates in the fission of mitochondria and MROs.
Gender Differences in Behavioral and Neural Responses to Unfairness Under Social Pressure
Authors: Zheng Li , Ning Reipeng , Li Lin , Wei Chunli , Cheng Xuemei , Zhou Chu , Guo Xiuyan 
Published: October 2017

AbstractNumerous studies have revealed the key role of social pressure on individuals’ decision-making processes. However, the impact of social pressure on unfairness-related decision-making processes remains unclear. In the present study, we investigated how social pressure modulated men’s and women’s responses in an ultimatum game. Twenty women and eighteen men played the ultimatum game as responders in the scanner, where fair and unfair offers were tendered by proposers acting alone (low pressure) or by proposers endorsed by three supporters (high pressure). Results showed that men rejected more, whereas women accepted more unfair offers in the high versus low pressure context. Neurally, pregenual anterior cingulate cortex activation in women positively predicted their acceptance rate difference between contexts. In men, stronger right anterior insula activation and increased connectivity between right anterior insula and dorsal anterior cingulate cortex were observed when they receiving unfair offers in the high than low pressure context. Furthermore, more bilateral anterior insula and left dorsolateral prefrontal cortex activations were found when men rejected (relative to accepted) unfair offers in the high than low pressure context. These findings highlighted gender differences in the modulation of behavioral and neural responses to unfairness by social pressure.
Tripalmitin nanoparticle formulations significantly enhance paclitaxel antitumor activity against breast and lung cancer cells in vitro
Authors: Leiva María Carmen , Ortiz Raúl , Contreras-Cáceres Rafael , Perazzoli Gloria , Mayevych Iryna , López-Romero Juan Manuel , Sarabia Francisco , Baeyens Jose Manuel , Melguizo Consolación , Prados Jose 
Published: October 2017

AbstractPaclitaxel (PTX) is one of the drugs of choice in the treatment of breast and lung cancer. However, its severe side effects, including mielosuppression, cardiotoxicity and neurotoxicity, frequently cause treatment to be discontinued. Solid lipid nanoparticles (NPs) of glyceril tripalmitate (tripalmitin) loaded with PTX (Tripalm-NPs-PTX) including modifications by the addition of hexa(ethylene glycol), β-cyclodextrin and macelignan were developed. All NPs-PTX formulations displayed excellent hemocompatibility and significantly enhanced PTX antitumor activity in human breast (MCF7, MDAMB231, SKBR3 and T47D) and lung (A549, NCI-H520 and NCI-H460) cancer cells. Tripalm-NPs-PTX decreased PTX IC50 by as much as 40.5-fold in breast and 38.8-fold in lung cancer cells and Tripalm-NPs-PTX macelignan inhibited P-glycoprotein in resistant tumor cells. In addition, Tripalm-NPs-PTX significantly decreased the volume of breast and lung multicellular tumor spheroids that mimics in vivo tumor mass. Finally, Tripalm-NPs-PTX decreased the PTX IC50 of cancer stem cells (CSCs) derived from both lung and breast cancer cells (6.7- and 14.9-fold for MCF7 and A549 CSCs, respectively). These results offer a new PTX nanoformulation based on the use of tripalmitin which improves the antitumor activity of PTX and that may serve as an alternative PTX delivery system in breast and lung cancer treatment.
Motor recovery after activity-based training with spinal cord epidural stimulation in a chronic motor complete paraplegic
Authors: Rejc Enrico , Angeli Claudia A. , Atkinson Darryn , Harkema Susan J. 
Published: October 2017

AbstractThe prognosis for recovery of motor function in motor complete spinal cord injured (SCI) individuals is poor. Our research team has demonstrated that lumbosacral spinal cord epidural stimulation (scES) and activity-based training can progressively promote the recovery of volitional leg movements and standing in individuals with chronic clinically complete SCI. However, scES was required to perform these motor tasks. Herein, we show the progressive recovery of voluntary leg movement and standing without scES in an individual with chronic, motor complete SCI throughout 3.7 years of activity-based interventions utilizing scES configurations customized for the different motor tasks that were specifically trained (standing, stepping, volitional leg movement). In particular, this report details the ongoing neural adaptations that allowed a functional progression from no volitional muscle activation to a refined, task-specific activation pattern and movement generation during volitional attempts without scES. Similarly, we observed the re-emergence of muscle activation patterns sufficient for standing with independent knee and hip extension. These findings highlight the recovery potential of the human nervous system after chronic clinically motor complete SCI.
Prediction model of voltage–time characteristics for SF6 long gap under VFTO and lightning impulse voltage
Authors: Zhang Lu , Wang Sen , Sun Lei , Mao Chen , Pu Lu , Zhang Qiaogen 
Published: October 2017

Voltage–time (V –t) characteristics of the SF6 long gap under very fast transient overvoltage (VFTO) draw wide attention at the high‐voltage transmission systems. In this research, a generating system of VFTO and lightning impulse (LI) up to 2.5 MV was set up. The V –t characteristics for SF6 gaps with hundreds of millimetres length under negative LI and VFTO were researched. Experimental results indicated the rate of rising of V –t curve for the sphere‐plane gap under VFTO was moderate, and V –t curve under LI was rapid, resulting in the intersection of the two types of V –t curves. However, for the rod‐plane gap, the V –t curve under VFTO was below that under LI at 0.5 MPa. The shape of V –t curve had many relationships with discharge propagation velocity in the SF6 gap, which was determined by the gap distance, field non‐uniformity, gas pressure and applied voltages. Based on analysis of discharge process and physical background of V –t curve, the semi‐empirical formulae were derived and the prediction model was established. It was demonstrated the predicted V –t curves could accurately predict breakdown characteristics of long SF6 gas gaps
Partial discharge detection by extracting UHF signal from inner grading electrode of insulating spacer in GIS
Authors: Shao Xian‐Jun , He Wen‐Lin , Xu Jia‐Long , Zhu Ming‐Xiao , Zhang Guan‐Jun 
Published: October 2017

In this study, a novel ultra‐high frequency (UHF) sensor using an inner grading electrode inside an insulting spacer is employed to detect gas‐insulated switchgear (GIS) partial discharge (PD). The simulation of the waveguide modes of the 252 kV GIS and the frequency response characteristics of this UHF sensor are performed by using the finite difference time domain (FDTD) method. Three kinds of typical defects are employed to investigate the PD detection characteristics of this UHF sensor. It is shown that the resonance frequencies of this sensor are extremely abundant below 3 GHz, and the major resonance frequencies around 0.5–1.2 and 2.2–3 GHz. The phase‐resolved PD (PRPD) images accumulated by using this UHF sensor present the typical PRPD images of defects. The main frequency spectrum of the metal protrusion on a high‐voltage conductor and floating potential defects are distributed below 1.5 GHz, which is consistent with waveguide mode simulation. A resonance frequency of a grading electrode UHF sensor appears at about 115 MHz, which is close to the simulation value of a resonance frequency at 140 MHz. The PD detection sensitivity of this sensor is much higher than that of an external sensor; however, it is a little lower than that of an internal sensor.
RoboTAP: Target priorities for robotic microlensing observations
Authors: Hundertmark M. , Street R. A. , Tsapras Y. , Bachelet E. , Dominik M. , Horne K. , Bozza V. , Bramich D. M. , Cassan A. , D’Ago G. , Figuera Jaimes R. , Kains N. , Ranc C. , Schmidt R. W. , Snodgrass C. , Wambsganss J. , Steele I. A. , Mao S. , Ment K. , Menzies J. , Li Z. , Cross S. , Maoz D. , Shvartzvald Y. 
Published: October 2017

Context. The ability to automatically select scientifically-important transient events from an alert stream of many such events, and to conduct follow-up observations in response, will become increasingly important in astronomy. With wide-angle time domain surveys pushing to fainter limiting magnitudes, the capability to follow-up on transient alerts far exceeds our follow-up telescope resources, and effective target prioritization becomes essential. The RoboNet-II microlensing program is a pathfinder project, which has developed an automated target selection process (RoboTAP) for gravitational microlensing events, which are observed in real time using the Las Cumbres Observatory telescope network.
Aims. Follow-up telescopes typically have a much smaller field of view compared to surveys, therefore the most promising microlensing events must be automatically selected at any given time from an annual sample exceeding 2000 events. The main challenge is to select between events with a high planet detection sensitivity, with the aim of detecting many planets and characterizing planetary anomalies.
Methods. Our target selection algorithm is a hybrid system based on estimates of the planet detection zones around a microlens. It follows automatic anomaly alerts and respects the expected survey coverage of specific events.
Results. We introduce the RoboTAP algorithm, whose purpose is to select and prioritize microlensing events with high sensitivity to planetary companions. In this work, we determine the planet sensitivity of the RoboNet follow-up program and provide a working example of how a broker can be designed for a real-life transient science program conducting follow-up observations in response to alerts; we explore the issues that will confront similar programs being developed for the Large Synoptic Survey Telescope (LSST) and other time domain surveys.
Postoperative Imaging after Impingement Surgery
Authors: Grob Karl , Kim Chan-Hi , Dietrich Tobias 
Published: October 2017

AbstractIn addition to the patient's medical history and clinical evaluation, conventional radiographs and magnetic resonance imaging (MRI) are important tools to indicate appropriate conservative treatment or even revision surgery in patients with symptoms after surgical management of femoroacetabular impingement (FAI). We present an overview of current evidence in postoperative imaging after impingement surgery. Undercorrection of the underlying osseous FAI configuration is the most frequent indication for revision surgery within the first 2 years after index FAI surgery. Femoral neck fractures, iatrogenic chondral injuries, early conversion to total hip arthroplasty, loose bodies, and heterotopic ossifications are rare but typical early complications after surgical treatment of FAI. Abnormal MRI findings after FAI surgery such as intra-articular adhesions, labral tears, cartilage defects, and anterior capsular defects are common findings in both asymptomatic and symptomatic postoperative patients. Avascular necrosis of the femoral head is an extremely rare complication after surgical treatment of FAI.