bluuebunny/crossref_metadata_2025 huggingface dataset:
Drosophila HUWE1 Ubiquitin Ligase Regulates Endoreplication and Antagonizes JNK Signaling During Salivary Gland Development
Authors: Yanku Yifat , Bitman-Lotan Eliya , Zohar Yaniv , Kurant Estee , Zilke Norman , Eilers Martin , Orian Amir
Published: September 2018

The HECT-type ubiquitin ligase HECT, UBA and WWE Domain Containing 1, (HUWE1) regulates key cancer-related pathways, including the Myc oncogene. It affects cell proliferation, stress and immune signaling, mitochondria homeostasis, and cell death. HUWE1 is evolutionarily conserved from Caenorhabditis elegance to Drosophila melanogaster and Humans. Here, we report that the Drosophila ortholog, dHUWE1 (CG8184), is an essential gene whose loss results in embryonic lethality and whose tissue-specific disruption establishes its regulatory role in larval salivary gland development. dHUWE1 is essential for endoreplication of salivary gland cells and its knockdown results in the inability of these cells to replicate DNA. Remarkably, dHUWE1 is a survival factor that prevents premature activation of JNK signaling, thus preventing the disintegration of the salivary gland, which occurs physiologically during pupal stages. This function of dHUWE1 is general, as its inhibitory effect is observed also during eye development and at the organismal level. Epistatic studies revealed that the loss of dHUWE1 is compensated by dMyc proeitn expression or the loss of dmP53. dHUWE1 is therefore a conserved survival factor that regulates organ formation during Drosophila development.
Efficient Antifungal and Flame-Retardant Properties of ZnO-TiO2-Layered Double-Nanostructures Coated on Bamboo Substrate
Authors: Ren Danjing , Li Jingpeng , Xu Jun , Wu Zaixing , Bao Yongjie , Li Neng , Chen Yuhe
Published: September 2018

A facile method to synthesize ZnO-TiO2-layered double-nanostructures with the average thickness of 20 μm on a bamboo substrate was proposed to improve the antifungal and flame-retardant properties. The cross-linked wurtzite ZnO nanostructures with an average thickness of approximately 0.14 μm were uniformly distributed on the anatase TiO2 surface. The energy-dispersive X-ray spectroscopy (EDS) confirmed that the ZnO-TiO2 coating on bamboo was a layered double nanostructure. During a two-month antifungal test conducted in an outdoor environment, the fungi began to grow after one week on pristine bamboo and three weeks on ZnO-bamboo and TiO2-bamboo. Furthermore, there was an infected area of 100% after four weeks for pristine bamboo and six weeks for ZnO-bamboo, while there was an infected area of 43% after eight weeks for TiO2-bamboo. By comparison, there was no visible fungal growth on ZnO-TiO2-bamboo until the end of the test. The electron spin resonance (ESR) technique has demonstrated that the reactive oxygen species (ROS) of •O2− and •OH were produced from the ZnO-TiO2 surface under visible light irradiation (λ > 420 nm). This large quantity of •O2− compared to •OH is considered to be mainly responsible for the inactivation of fungi. Additionally, the limiting oxygen index has increased from 25.6% to 30.2% after being covered with a ZnO-TiO2 coating, which revealed a significant enhancement of its flame-retardant property.
Erosion Behavior of API X120 Steel: Effect of Particle Speed and Impact Angle
Authors: C. Okonkwo Paul , H. Sliem Mostafa , Hassan Sk Mobbassar , Abdul Shakoor Rana , Amer Mohamed Adel Mohamed , M. Abdullah Aboubakr , Kahraman Ramazan
Published: September 2018

The dry erosion behavior of API-X120 pipeline steel was investigated, under the erosive interaction of aluminum oxide particulates, in a range of speed (43–167 m·s−1) and impact angle (30°–90°). Erosion behavior is characterized by surface profile measurement, weight loss measurement, and surface morphology analysis by SEM/EDX. Optical profilometry revealed that the eroded area increased with elevating speed of particles while the penetration depth increased with the increases in impact angle as well as particle speed. Percent weight loss and normalized erosion rate indicated that the lower impact angles and higher speeds led to higher materials loss and erosion. SEM analyses on various combinations of impact angles and particle speeds demonstrated the predominant erosion mechanism under those specific conditions; attributed to the intensity of the resolved components of the momentum vector horizontal or normal to the target metal surface under those conditions.
Entropy Generation Rates in Two-Dimensional Rayleigh–Taylor Turbulence Mixing
Authors: Yang Xinyu , He Haijiang , Xu Jun , Wei Yikun , Zhang Hua
Published: September 2018

Entropy generation rates in two-dimensional Rayleigh–Taylor (RT) turbulence mixing are investigated by numerical calculation. We mainly focus on the behavior of thermal entropy generation and viscous entropy generation of global quantities with time evolution in Rayleigh–Taylor turbulence mixing. Our results mainly indicate that, with time evolution, the intense viscous entropy generation rate s u and the intense thermal entropy generation rate S θ occur in the large gradient of velocity and interfaces between hot and cold fluids in the RT mixing process. Furthermore, it is also noted that the mixed changing gradient of two quantities from the center of the region to both sides decrease as time evolves, and that the viscous entropy generation rate ⟨ S u ⟩ V and thermal entropy generation rate ⟨ S θ ⟩ V constantly increase with time evolution; the thermal entropy generation rate ⟨ S θ ⟩ V with time evolution always dominates in the entropy generation of the RT mixing region. It is further found that a “smooth” function ⟨ S u ⟩ V ∼ t 1 / 2 and a linear function ⟨ S θ ⟩ V ∼ t are achieved in the spatial averaging entropy generation of RT mixing process, respectively.
Control of the Bidirectional Buck-Boost Converter Operating in Boundary Conduction Mode to Provide Hold-Up Time Extension
Authors: Lopez-Santos Oswaldo , Urrego-Aponte José Omar , Tilaguy-Lezama Sebastián , Almansa-López José David
Published: September 2018

A hold-up time extension circuit (HTEC) is used to charge and discharge an auxiliary capacitor. This capacitor stores the energy required to extend the operation time of critical loads experiencing short duration failures (SDF) at the DC bus to which they are connected. This paper presents complete modeling and a control-wise approach to a parallel HTEC based on the bidirectional buck-boost converter, which operates in Boundary Conduction Mode (BCM) with a variable switching frequency. The circuit permanently regulates the voltage of the auxiliary capacitor as well as the voltage of the DC bus during SDF, which is uncommon in industrial versions of HTEC. Enforcing the operation in BCM allows a reduction in the size of the inductor in the converter without requiring additional control circuitry. The entire behavior of the proposed HTEC, in all its operation modes, was analyzed theoretically and validated using simulation and experimental results, showing the potential of the circuit to be used in real applications.
Fault Diagnosis Based on an Approach Combining a Spectrogram and a Convolutional Neural Network with Application to a Wind Turbine System
Authors: Yu Wenxin , Huang Shoudao , Xiao Weihong
Published: September 2018

To investigate problems involving wind turbines that easily occur but are hard to diagnose, this paper presents a wind turbine (WT) fault diagnosis algorithm based on a spectrogram and a convolutional neural network. First, the original data are sampled into a phonetic form. Then, the data are transformed into a spectrogram in the time-frequency domain. Finally, the data are sent into a convolutional neural network (CNN) model with batch regularization for training and testing. Experimental results show that the method is suitable for training a large number of samples and has good scalability. Compared with Back Propagation Neural Network (BPNN), Support Vector Machine (SVM), Extreme Learning Machine (ELM), and other fault diagnosis methods, the average diagnostic correctness rate is higher; so, the method can provide more accurate reference information for wind turbine fault diagnosis.
Biodiesel Production from a Novel Nonedible Feedstock, Soursop (Annona muricata L.) Seed Oil
Authors: Su Chia-Hung , Nguyen Hoang Chinh , Pham Uyen Khanh , Nguyen My Linh , Juan Horng-Yi
Published: September 2018

This study investigated the optimal reaction conditions for biodiesel production from soursop (Annona muricata) seeds. A high oil yield of 29.6% (w/w) could be obtained from soursop seeds. Oil extracted from soursop seeds was then converted into biodiesel through two-step transesterification process. A highest biodiesel yield of 97.02% was achieved under optimal acid-catalyzed esterification conditions (temperature: 65 °C, 1% H2SO4, reaction time: 90 min, and a methanol:oil molar ratio: 10:1) and optimal alkali-catalyzed transesterification conditions (temperature: 65 °C, reaction time: 30 min, 0.6% NaOH, and a methanol:oil molar ratio: 8:1). The properties of soursop biodiesel were determined and most were found to meet the European standard EN 14214 and American Society for Testing and Materials standard D6751. This study suggests that soursop seed oil is a promising biodiesel feedstock and that soursop biodiesel is a viable alternative to petrodiesel.
Characteristics Analysis of Doubly Fed Magnetic Geared Motor Considering Winding Frequency Conditions
Authors: Shin Homin , Chang Junghwan
Published: September 2018

The magnetic geared motor, which has improved torque density because of the magnetic gearing effect, has been researched. However, its narrow operating region due to the operating mechanism by the magnetic gearing effect and field flux by the PM is a challenge that needs to be overcome. Whereas, the doubly fed magnetic geared motor (DFMGM) can extend the operating region because of the double stator and double winding structure with the individual frequency control of the current fed to the inner and outer windings. However, two rotating magnetic fields, which are produced by the inner and outer winding flux, exist at the air-gap, and the large numbers of space harmonic components of the modulated flux density are produced at the air-gaps. These space harmonic components, which are produced by the winding MMF, influence not only the back-EMF of the winding but also the performances of the operating torque. Besides, the inner and outer windings affect each other in the back-EMF, and its characteristics appears differently in the inner and outer windings. Thus, in this paper, the structure, operating strategy, and basic characteristics according to the frequency condition in the inner and outer windings are presented.
Analytical Measurements and Efficient Process Generation Using a Dual–Arm Robot Equipped with Electronic Pipettes
Authors: Fleischer Heidi , Baumann Daniel , Joshi Shalaka , Chu Xianghua , Roddelkopf Thomas , Klos Michael , Thurow Kerstin
Published: September 2018

The continued growth in life sciences is being accompanied by the constantly rising demand for robotic systems. Today, bioscreening and high–throughput screening processes are well automated. In contrast, a deficit can be found in the area of analytical measurements with complex and frequently changing processes. Robots undertake not only transportation tasks, but also direct sample manipulation and subsequent analytical measurements. Due to their human-like structure, dual-arm robots perform such processes similar to human operation. Liquid handling is required to transfer chemicals, to prepare standard solutions, or to dilute samples. Two electronic pipettes with different volume ranges (5–200 µL and 50–1000 µL) were integrated into a dual–arm robotic system. The main focus in this publication is the software interface for alternating robot and pipette control as well as the high–level process control system. The performance using a dual–arm robot equipped with electronic pipettes and conventional manual pipettes was determined and compared. The automation system presented is the first integration of a dual-arm robot in analytical measurement processes. Conventional manual laboratory pipettes and electronic pipettes are simultaneously used for liquid-handling tasks. The software control system enables a flexible and user-friendly process generation.
Vibrational Study of Iodide-Based Room-Temperature Ionic-Liquid Effects on Candidate N719-Chromophore/Titania Interfaces for Dye-Sensitised Solar-Cell Applications from Ab-Initio Based Molecular-Dynamics Simulation
Authors: Krishnan Yogeshwaran , Byrne Aaron , English Niall J.
Published: September 2018

The accurate ab-initio modelling of prototypical and well-representative photo-active interfaces for candidate dye-sensitised solar cells is a challenging problem. To this end, using ab-initio molecular-dynamics (AIMD) simulation based on Density Functional Theory (DFT), the effects of explicit solvation by iodide-based, I−[bmim]+ room-temperature ionic liquids (RTILs) have been assessed on modelling a N719-chromophore sensitising dye adsorbed onto an anatase-titania (101) surface. In particular, the vibrational spectra for this model photo-active interface were calculated by means of Fourier transformed mass-weighted velocity autocorrelation functions. These were compared with experiment and against each other to gain an understanding of how using iodine-based RTILs as the electrolytic hole acceptor alters the dynamical properties of the widely-used N719 dye. The effect of Perdew-Burke-Ernzerhof (PBE) and Becke-Lee-Yang-Parr (BLYP) functionals on the vibrational spectra were assessed. PBE generally performed best in producing spectra which matched the typically expected experimental frequency modes.
A Simple-to-Implement Fault Diagnosis Method for Open Switch Fault in Wind System PMSG Drives without Threshold Setting
Authors: Yanghong Tan , Haixia Zhang , Ye Zhou
Published: September 2018

The conversion system is a major contributor to failure rates. These faults lead to time and cost consuming. Fault diagnosis capabilities pay as a solver to achieve a steady system. This paper presents a full analysis of permanent magnet synchronous generator wind system (PMSGWS) and proposes a special RMS voltage-based fault diagnosis method. The full analysis presents a comprehensive knowledge of faulty behaviors especially under arm current flowing or cutting off. Due to enough knowledge of faulty behaviors, the implementation of the detection method without threshold setting is contributed by the special RMS voltage. Its sample period is set longer than the time of the maximum pulse width ratio (MPR) and shorter than the fault show time of lower tube voltage. Due to this, the detection speed and robustness are achieved. By these simple settings for the fault diagnosis method, the faulty switch is detected in less than 1/4 of the period. Simulation and experimental results confirm the validity and feasibility of the new proposed fault detection method.
Assessment of Alternative Agricultural Land Use Options for Extending the Availability of the Ogallala Aquifer in the Northern High Plains of Texas
Authors: Chen Yong , Marek Gary W. , Marek Thomas H. , Moorhead Jerry E. , Heflin Kevin R. , Brauer David K. , Gowda Prasanna H. , Srinivasan Raghavan
Published: September 2018

The Ogallala Aquifer has experienced a continuous decline in water levels due to decades of irrigation pumping with minimal recharge. Corn is one of the major irrigated crops in the semi-arid Northern High Plains (NHP) of Texas. Selection of less water-intensive crops may provide opportunities for groundwater conservation. Modeling the long-term hydrologic impacts of alternative crops can be a time-saving and cost-effective alternative to field-based experiments. A newly developed management allowed depletion (MAD) irrigation scheduling algorithm for Soil and Water Assessment Tool (SWAT) was used in this study. The impacts of irrigated farming, dryland farming, and continuous fallow on water conservation were evaluated. Results indicated that simulated irrigation, evapotranspiration, and crop yield were representative of the measured data. Approximately 19%, 21%, and 32% reductions in annual groundwater uses were associated with irrigated soybean, sunflower, and sorghum, respectively, as compared to irrigated corn. On average, annual soil water depletion was more than 52 mm for dryland farming scenarios. In contrast, only 18 mm of soil water was lost to evaporation annually, for the long-term continuous fallow simulation. The fallow scenario also showed 31 mm of percolation for aquifer recharge.
Water Salinity Should Be Reduced for Irrigation to Minimize Its Risk of Increased Soil N2O Emissions
Authors: Wei Qi , Xu Junzeng , Liao Linxian , Li Yawei , Wang Haiyu , Rahim Shah Fahad
Published: September 2018

To reveal the effect of irrigation salinity on soil nitrous oxide (N2O) emission, pot experiments were designed with three irrigation salinity levels (NaCl and CaCl2 of 1, 2.5 and 4 g/L equivalence, Ec = 3.6, 8.1 and 12.7 ds/m), either for 0 kg N/ha (N0) or 120 kg N/ha (N120) nitrogen inputs. N2O emissions from soils irrigated at different salinity levels varied in a similar pattern which was triggered by soil moisture dynamics. Yet, the magnitudes of pulse N2O fluxes were significantly varied, with the peak flux at 5 g/L irrigation salinity level being much higher than at 2 and 8 g/L. Compared to fresh water irrigated soils, cumulative N2O fluxes were reduced by 22.7% and 39.6% (N0), 29.1% and 39.2% (N120) for soils irrigated with 2 and 8 g/L saline water, while they were increased by 87.7% (N0) and 58.3% (N120) for soils irrigated with 5 g/L saline water. These results suggested that the effect degree of salinity on consumption and production of N2O might vary among irrigation salinity ranges. As such, desalinating brackish water to a low salinity level (such as 2 g/L) before it is used for irrigation might be helpful for solving water resources crises and mitigating soil N2O emissions.
Organisational Justice, Burnout, and Engagement in University Students: A Comparison between Stressful Aspects of Labour and University Organisation
Authors: Navarro-Abal Yolanda , Gómez-Salgado Juan , López-López María José , Climent-Rodríguez José Antonio
Published: September 2018

Burnout, engagement, and organisational justice concepts are usually studied in the context of labour organisations, but not in universities. For this, the objective of this research is to identify the students’ empirically evidenced relationships in the employment context, such as levels of organisational justice, stress indicators, burnout and work commitment. On the other hand, engagement is analysed as a mediating variable that explains the relationship between organisational justice and burnout. A sample of 543 students from three Spanish universities, selected by purposive sampling, is used ensuring voluntary and anonymous participation. The instruments used to measure the four variables to analyse are a protocol for data collection, MBI-SS instrument for Academic Burnout, Utrecht Work Engagement Student Scale (UWES) for Engagement and the Scale of Organisational Justice for Organisational Justice. As a result, college students show behaviours that promote academic achievement, and they feel more engaged when they are treated fairly. As for the burnout syndrome dimensions, average levels of emotional exhaustion and academic efficacy, and high levels of cynicism are revealed. In addition, the proposed structural equation model supports the main hypothesis; engagement is a mediating variable in the organisational justice and burnout relationship. To conclude, academic stress and its explanatory framework cannot be conceived only from an organisational perspective, where the context of each student must be considered. The adoption of organisational preventive measures can be relevant in ensuring a healthy and conducive academic performance in our students.
Contribution of Resident Stem Cells to Liver and Biliary Tree Regeneration in Human Diseases
Authors: Overi Diletta , Carpino Guido , Cardinale Vincenzo , Franchitto Antonio , Safarikia Samira , Onori Paolo , Alvaro Domenico , Gaudio Eugenio
Published: September 2018

Two distinct stem/progenitor cell populations of biliary origin have been identified in the adult liver and biliary tree. Hepatic Stem/progenitor Cells (HpSCs) are bipotent progenitor cells located within the canals of Hering and can be differentiated into mature hepatocytes and cholangiocytes; Biliary Tree Stem/progenitor Cells (BTSCs) are multipotent stem cells located within the peribiliary glands of large intrahepatic and extrahepatic bile ducts and able to differentiate into hepatic and pancreatic lineages. HpSCs and BTSCs are endowed in a specialized niche constituted by supporting cells and extracellular matrix compounds. The actual contribution of these stem cell niches to liver and biliary tree homeostatic regeneration is marginal; this is due to the high replicative capabilities and plasticity of mature parenchymal cells (i.e., hepatocytes and cholangiocytes). However, the study of human liver and biliary diseases disclosed how these stem cell niches are involved in the regenerative response after extensive and/or chronic injuries, with the activation of specific signaling pathways. The present review summarizes the contribution of stem/progenitor cell niches in human liver diseases, underlining mechanisms of activation and clinical implications, including fibrogenesis and disease progression.
Blood Pressure Profile and N-Terminal-proBNP Dynamics in Response to Intravenous Methylprednisolone Pulse Therapy of Severe Graves’ Orbitopathy
Authors: Miskiewicz Piotr , Milczarek-Banach Justyna , Bednarczuk Tomasz , Opolski Grzegorz , Glowczynska Renata
Published: September 2018

Hypercortisolemia is associated with increased risk of hypertension. Natural and synthetic glucocorticoids (GCs) have different effects on blood pressure (BP). The effect of synthetic GCs on BP depends on the dose, treatment duration, type of GCs, and route of administration. Intravenous methylprednisolone (IVMP) pulse therapy is the first line of treatment for severe Graves’ orbitopathy (GO). The aim of this study was to evaluate influence of IVMP pulses on BP and N-terminal pro-brain natriuretic peptide (NT-proBNP) dynamics. A total of 32 patients with GO were treated with one IVMP pulse every week for 12 weeks. We performed 48-h BP monitoring (24-h before and 24-h after IVMP) and measured NT-proBNP before, 24 h, and 48 h after the 1st, 6th, and 12th IVMP pulse. Mean BP did not change after any of the pulses. We did not observe an increase in maximal systolic BP or mean nocturnal BP, except after the last pulse. Additionally, the dipping phenomenon was less frequent after the last pulse. We found a significant increase in median NT-proBNP levels after all analyzed pulses. Our study suggests that IVMP may have an unfavorable cumulative effect on BP. Variation in NT-proBNP concentration indicates a compensatory effect of brain natriuretic peptide secretion.
G Protein-Coupled Receptor Systems as Crucial Regulators of DNA Damage Response Processes
Authors: Leysen Hanne , Van Gastel Jaana , Hendrickx Jhana O. , Santos-Otte Paula , Martin Bronwen , Maudsley Stuart
Published: September 2018

G protein-coupled receptors (GPCRs) and their associated proteins represent one of the most diverse cellular signaling systems involved in both physiological and pathophysiological processes. Aging represents perhaps the most complex biological process in humans and involves a progressive degradation of systemic integrity and physiological resilience. This is in part mediated by age-related aberrations in energy metabolism, mitochondrial function, protein folding and sorting, inflammatory activity and genomic stability. Indeed, an increased rate of unrepaired DNA damage is considered to be one of the ‘hallmarks’ of aging. Over the last two decades our appreciation of the complexity of GPCR signaling systems has expanded their functional signaling repertoire. One such example of this is the incipient role of GPCRs and GPCR-interacting proteins in DNA damage and repair mechanisms. Emerging data now suggest that GPCRs could function as stress sensors for intracellular damage, e.g., oxidative stress. Given this role of GPCRs in the DNA damage response process, coupled to the effective history of drug targeting of these receptors, this suggests that one important future activity of GPCR therapeutics is the rational control of DNA damage repair systems.
Parathyroid Hormone (PTH) Increases Skeletal Tumour Growth and Alters Tumour Distribution in an In Vivo Model of Breast Cancer
Authors: Brown Hannah K. , Allocca Gloria , Ottewell Penelope D. , Wang Ning , Brown Nicola J. , Croucher Peter I. , Eaton Colby L. , Holen Ingunn
Published: September 2018

Breast cancer cells colonize the skeleton by homing to specific niches, but the involvement of osteoblasts in tumour cell seeding, colonization, and progression is unknown. We used an in vivo model to determine how increasing the number of cells of the osteoblast lineage with parathyroid hormone (PTH) modified subsequent skeletal colonization by breast cancer cells. BALB/c nude mice were injected for five consecutive days with PBS (control) or PTH and then injected with DiD-labelled breast cancer cells via the intra-cardiac route. Effects of PTH on the bone microenvironment and tumour cell colonization and growth was analyzed using bioluminescence imaging, two-photon microscopy, and histological analysis. PTH treatment caused a significant, transient increase in osteoblast numbers compared to control, whereas bone volume/structure in the tibia was unaffected. There were no differences in the number of tumour cells seeding to the tibias, or in the number of tumours in the hind legs, between the control and PTH group. However, animals pre-treated with PTH had a significantly higher number of tumour colonies distributed throughout skeletal sites outside the hind limbs. This is the first demonstration that PTH-induced stimulation of osteoblastic cells may result in alternative skeletal sites becoming available for breast cancer cell colonization.
The Tissue-Engineered Human Psoriatic Skin Substitute: A Valuable In Vitro Model to Identify Genes with Altered Expression in Lesional Psoriasis
Authors: Rioux Geneviève , Pouliot-Bérubé Claudia , Simard Mélissa , Benhassine Manel , Soucy Jacques , Guérin Sylvain , Pouliot Roxane
Published: September 2018

Psoriasis is a chronic inflammatory skin disease for which no cure has emerged. Its complex etiology requires the development of an in vitro model representative of the pathology. In this study, we exploited gene profiling analyses on microarray in order to characterize and further optimize the production of a human psoriatic skin model representative of this in vivo skin disease. Various skin substitutes were produced by tissue-engineering using biopsies from normal, healthy donors, or from lesional or non-lesional skin samples from patients with psoriasis, and their gene expression profiles were examined by DNA microarray. We demonstrated that more than 3540 and 1088 genes (two-fold change) were deregulated between healthy/lesional and lesional/non-lesional psoriatic substitutes, respectively. Moreover, several genes related to lipid metabolism, such as PLA2G4E and PLA2G4C, were identified as repressed in the lesional substitutes. In conclusion, gene profiling analyses identified a list of deregulated candidate genes associated with various metabolic pathways that may contribute to the progression of psoriasis.
Genome Wide Transcriptome Analysis Reveals Complex Regulatory Mechanisms Underlying Phosphate Homeostasis in Soybean Nodules
Authors: Xue Yingbin , Zhuang Qingli , Zhu Shengnan , Xiao Bixian , Liang Cuiyue , Liao Hong , Tian Jiang
Published: September 2018

Phosphorus (P) deficiency is a major limitation for legume crop production. Although overall adaptations of plant roots to P deficiency have been extensively studied, only fragmentary information is available in regard to root nodule responses to P deficiency. In this study, genome wide transcriptome analysis was conducted using RNA-seq analysis in soybean nodules grown under P-sufficient (500 μM KH2PO4) and P-deficient (25 μM KH2PO4) conditions to investigate molecular mechanisms underlying soybean (Glycine max) nodule adaptation to phosphate (Pi) starvation. Phosphorus deficiency significantly decreased soybean nodule growth and nitrogenase activity. Nodule Pi concentrations declined by 49% in response to P deficiency, but this was well below the 87% and 88% decreases observed in shoots and roots, respectively. Nodule transcript profiling revealed that a total of 2055 genes exhibited differential expression patterns between Pi sufficient and deficient conditions. A set of (differentially expressed genes) DEGs appeared to be involved in maintaining Pi homeostasis in soybean nodules, including eight Pi transporters (PTs), eight genes coding proteins containing the SYG1/PHO81/XPR1 domain (SPXs), and 16 purple acid phosphatases (PAPs). The results suggest that a complex transcriptional regulatory network participates in soybean nodule adaption to Pi starvation, most notable a Pi signaling pathway, are involved in maintaining Pi homeostasis in nodules.
Ghrelin Receptor Antagonism of Methamphetamine-Induced Conditioned Place Preference and Intravenous Self-Administration in Rats
Authors: Havlickova Tereza , Charalambous Chrysostomos , Lapka Marek , Puskina Nina , Jerabek Pavel , Sustkova-Fiserova Magdalena
Published: September 2018

Methamphetamine abuse imposes a significant burden on individuals and society worldwide, and an effective therapy of methamphetamine addiction would provide distinguished social benefits. Ghrelin significantly participates in reinforcing neurobiological mechanisms of stimulants, including amphetamines; thus, ghrelin antagonism is proposed as a promising addiction treatment. The aim of our study was to elucidate whether the pretreatment with growth hormone secretagogue receptor (GHS-R1A) antagonist, substance JMV2959, could reduce the methamphetamine intravenous self-administration (IVSA) and the tendency to relapse, and whether JMV2959 could reduce or prevent methamphetamine-induced conditioned place preference (CPP) in rats. Following an adequate maintenance period, JMV2959 3 mg/kg was administered intraperitoneally 20 min before three consequent daily 180 min sessions of methamphetamine IVSA under a fixed ratio FR1, which significantly reduced the number of active lever-pressings, the number of infusions, and the amount of the consumed methamphetamine dose. Pretreatment with JMV2959 also reduced or prevented relapse-like behavior tested in rats on the 12th day of the abstinence period. Pretreatment with JMV2959 significantly reduced the expression of methamphetamine-induced CPP. Simultaneous administration of JMV2959 with methamphetamine during the conditioning period significantly reduced the methamphetamine-CPP. Our results encourage further research of the ghrelin antagonism as a potential new pharmacological tool for methamphetamine addiction treatment.
Combined Fluid Shear Stress and Melatonin Enhances the ERK/Akt/mTOR Signal in Cilia-Less MC3T3-E1 Preosteoblast Cells
Authors: Kim Chi Hyun , Jeung Eui-Bae , Yoo Yeong-Min
Published: September 2018

We investigated whether combined fluid shear stress (FSS) and melatonin stimulated signal transduction in cilia-less MC3T3-E1 preosteoblast cells. MC3T3-E1 cells were treated with chloral hydrate or nocodazole, and mechanotransduction sensor primary cilia were removed. p-extracellular signal–regulated kinase (ERK) and p-Akt with/without melatonin increased with nocodazole treatment and decreased with chloral hydrate treatment, whereas p-ERK and p-Akt in FSS with/without melatonin increased in cilia-less groups compared to cilia groups. Furthermore, p-mammalian target of rapamycin (mTOR) with FSS-plus melatonin increased in cilia-less groups compared to only melatonin treatments in cilia groups. Expressions of Bcl-2, Cu/Zn-superoxide dismutase (SOD), and catalase proteins were higher in FSS with/without melatonin with cilia-less groups than only melatonin treatments in cilia groups. Bax protein expression was high in FSS-plus melatonin with chloral hydrate treatment. In chloral hydrate treatment with/without FSS, expressions of Cu/Zn-SOD, Mn-SOD, and catalase proteins were high compared to only-melatonin treatments. In nocodazole treatment, Mn-SOD protein expression without FSS was high, and catalase protein level with FSS was low, compared to only melatonin treatments. These data show that the combination with FSS and melatonin enhances ERK/Akt/mTOR signal in cilia-less MC3T3-E1, and the enhanced signaling in cilia-less MC3T3-E1 osteoblast cells may activate the anabolic effect for the preservation of cell structure and function.
Validation of Suitable Housekeeping Genes for the Normalization of mRNA Expression for Studying Tumor Acidosis
Authors: Lemma Silvia , Avnet Sofia , Meade Michael Joseph , Chano Tokuhiro , Baldini Nicola
Published: September 2018

Similar to other types of cancer, acidification of tumor microenvironment is an important feature of osteosarcoma, and a major source of cellular stress that triggers cancer aggressiveness, drug resistance, and progression. Among the different effects of low extracellular pH on tumor cells, we have recently found that short-term exposure to acidosis strongly affects gene expression. This alteration might also occur for the most commonly used housekeeping genes (HKG), thereby causing erroneous interpretation of RT-qPCR data. On this basis, by using osteosarcoma cells cultured at different pH values, we aimed to identify the ideal HKG to be considered in studies on tumor-associated acidosis. We verified the stability of 15 commonly used HKG through five algorithms (NormFinder, geNorm, BestKeeper, ΔCT, coefficient of variation) and found that no universal HKG is suitable, since at least four HKG are necessary for proper normalization. Furthermore, according to the acceptable range of values, YWHAZ, GAPDH, GUSB, and 18S rRNA were the most stable reference genes at different pH. Our results will be helpful for future investigations focusing on the effect of altered microenvironment on cancer behavior, particularly on the effectiveness of anticancer therapies in acid conditions.
Advances in DNA Barcoding of Toxic Marine Organisms
Authors: Gong Shaohua , Ding Yanfei , Wang Yi , Jiang Guangze , Zhu Cheng
Published: September 2018

There are more than 200,000 marine species worldwide. These include many important economic species, such as large yellow croaker, ribbonfish, tuna, and salmon, but also many potentially toxic species, such as blue-green algae, diatoms, cnidarians, ctenophores, Nassarius spp., and pufferfish. However, some edible and toxic species may look similar, and the correct identification of marine species is thus a major issue. The failure of traditional classification methods in certain species has promoted the use of DNA barcoding, which uses short, standard DNA fragments to assist with species identification. In this review, we summarize recent advances in DNA barcoding of toxic marine species such as jellyfish and pufferfish, using genes including cytochrome oxidase I gene (COI), cytochrome b gene (cytb), 16S rDNA, internal transcribed spacer (ITS), and Ribulose-1,5-bisphosphate carboxylase oxygenase gene (rbcL). We also discuss the application of this technique for improving the identification of marine species. The use of DNA barcoding can benefit the studies of biological diversity, biogeography, food safety, and the detection of both invasive and new species. However, the technique has limitations, particularly for the analysis of complex objects and the selection of standard DNA barcodes. The development of high-throughput methods may offer solutions to some of these issues.
Fc Gamma Receptor IIb Expressed in Hepatocytes Promotes Lipid Accumulation and Gluconeogenesis
Authors: Shu Ting , Song Xiaomin , Cui Xingxing , Ge Weipeng , Gao Ran , Wang Jing
Published: September 2018

Non-alcoholic fatty liver disease (NAFLD) is characterized by ectopic lipid accumulation in the liver, usually combined with hepatic insulin resistance. Fc-gamma receptor-IIb (FcγRIIb) and its ligand are reported to be associated with obesity and type 2 diabetes mellitus (T2DM). As knowledge about FcγRIIb in the literature is mostly generated from studies on skeletal muscle tissue, the expression and function of FcγRIIb in the liver and hepatocytes are largely unknown. In this study, we identified the expression of FcγRIIb in primary cultured mouse hepatocytes: FcγRIIb was upregulated in response to oleic acid (OA) in a dose dependent manner. FcγRIIb knockdown using shRNA suppressed the lipid and triglyceride accumulation, and mRNA expression of ACC1, FASn, CD36, MTTP, and ApoB in OA-treated HepG2 cells. FcγRIIb deficiency mice fed with high fat diet (HFD) had significantly lower liver weight and liver to body weight ratio, as well as less triglyceride accumulation in the livers. In glycometabolism, FcγRIIb hindered insulin-induced phosphorylation of AKT and FOXO1, and in turn upregulated G6Pase and PEPCK mRNA expression, suggesting that FcγRIIb promotes gluconeogenesis by suppressing the AKT/FOXO1/G6Pase/PEPCK pathway in hepatocytes. This study reveals a novel role for FcγRIIb in regulating lipid metabolism and glycometabolism, and provides a new therapeutic target to improve NAFLD.
Assay of Secondary Anisotropy in Additively Manufactured Alloys for Dental Applications
Authors: Bassoli Elena , Denti Lucia
Published: September 2018

Even though additive manufacturing (AM) techniques have been available since the late 1980s, their application in medicine is still striving to gain full acceptance. For the production of dental implants, the use of AM allows to save time and costs, but also to ensure closer dimensional tolerances and higher repeatability, as compared to traditional manual processes. Among the several AM solutions, Laser Powder Bed Fusion (L-PBF) is the most appropriate for the production of metal prostheses. The target of this paper was to investigate the mechanical and microstructural characteristics of Co–Cr–Mo and Ti–6Al–4V alloys processed by L-PBF, with a specific focus on secondary anisotropy that is usually disregarded in the literature. Tensile specimens were built in the EOSINT-M270 machine, along different orientations perpendicular to the growth direction. Density, hardness, and tensile properties were measured and the results combined with microstructural and fractographic examination. For both alloys, the results provided evidence of high strength and hardness, combined with outstanding elongation and full densification. Extremely fine microstructures were observed, sufficient to account for the good mechanical response. Statistical analysis of the mechanical properties allowed to attest the substantial absence of secondary anisotropy. The result was corroborated by the observations of the microstructures and of the failure modes. Overall, the two alloys proved to be high-performing, in very close agreement with the values reported in the datasheets, independently of the build orientation.
Characterization and Preliminary Biological Evaluation of 3D-Printed Porous Scaffolds for Engineering Bone Tissues
Authors: Liu Chen-Guang , Zeng Yu-Ting , Kankala Ranjith Kumar , Zhang Shan-Shan , Chen Ai-Zheng , Wang Shi-Bin
Published: September 2018

Some basic requirements of bone tissue engineering include cells derived from bone tissues, three-dimensional (3D) scaffold materials, and osteogenic factors. In this framework, the critical architecture of the scaffolds plays a crucial role to support and assist the adhesion of the cells, and the subsequent tissue repairs. However, numerous traditional methods suffer from certain drawbacks, such as multi-step preparation, poor reproducibility, high complexity, difficulty in controlling the porous architectures, the shape of the scaffolds, and the existence of solvent residue, which limits their applicability. In this work, we fabricated innovative poly(lactic-co-glycolic acid) (PLGA) porous scaffolds, using 3D-printing technology, to overcome the shortcomings of traditional approaches. In addition, the printing parameters were critically optimized for obtaining scaffolds with normal morphology, appropriate porous architectures, and sufficient mechanical properties, for the accommodation of the bone cells. Various evaluation studies, including the exploration of mechanical properties (compressive strength and yield stress) for different thicknesses, and change of structure (printing angle) and porosity, were performed. Particularly, the degradation rate of the 3D scaffolds, printed in the optimized conditions, in the presence of hydrolytic, as well as enzymatic conditions were investigated. Their assessments were evaluated using the thermal gravimetric analyzer (TGA), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC). These porous scaffolds, with their biocompatibility, biodegradation ability, and mechanical properties, have enabled the embryonic osteoblast precursor cells (MC3T3-E1), to adhere and proliferate in the porous architectures, with increasing time. The generation of highly porous 3D scaffolds, based on 3D printing technology, and their critical evaluation, through various investigations, may undoubtedly provide a reference for further investigations and guide critical optimization of scaffold fabrication, for tissue regeneration.
Effect of Surface Nanocrystallization on Corrosion Resistance of the Conformed Cu-0.4%Mg Alloy in NaCl Solution
Authors: Song Dan , Jiang Jinghua , Guan Xiaonan , Qiao Yanxin , Li Xuebin , Chen Jianqing , Sun Jiapeng , Ma Aibin
Published: September 2018

Surface nano-crystallization (SNC) of a conform-extruded Cu-0.4 wt.% Mg alloy was successfully conducted by high-speed rotating wire-brushing to obtain the deformed zone with dislocation cells and nanocrystallines. SNC promotes the anodic dissolution and corrosion rate of the Cu-Mg alloy in the initial stage of immersion corrosion in 0.1 M NaCl solution. The weakened corrosion resistance is mainly attributed to the higher corrosion activity of SNC-treated alloy. With extending the immersion time, the SNC-treated alloy slows the corrosion rate dramatically and exhibits uniform dissolution of the surface. The formation of the dense corrosion products leads to the improvement of overall corrosion performance. It indicates that the SNC-treated Cu-Mg alloy can function reliably for a longer duration in a corrosive environment.
Advances in the Biology of Seed and Vegetative Storage Proteins Based on Two-Dimensional Electrophoresis Coupled to Mass Spectrometry
Authors: Mouzo Daniel , Bernal Javier , López-Pedrouso María , Franco Daniel , Zapata Carlos
Published: September 2018

Seed storage proteins play a fundamental role in plant reproduction and human nutrition. They accumulate during seed development as reserve material for germination and seedling growth and are a major source of dietary protein for human consumption. Storage proteins encompass multiple isoforms encoded by multi-gene families that undergo abundant glycosylations and phosphorylations. Two-dimensional electrophoresis (2-DE) is a proteomic tool especially suitable for the characterization of storage proteins because of their peculiar characteristics. In particular, storage proteins are soluble multimeric proteins highly represented in the seed proteome that contain polypeptides of molecular mass between 10 and 130 kDa. In addition, high-resolution profiles can be achieved by applying targeted 2-DE protocols. 2-DE coupled with mass spectrometry (MS) has traditionally been the methodology of choice in numerous studies on the biology of storage proteins in a wide diversity of plants. 2-DE-based reference maps have decisively contributed to the current state of our knowledge about storage proteins in multiple key aspects, including identification of isoforms and quantification of their relative abundance, identification of phosphorylated isoforms and assessment of their phosphorylation status, and dynamic changes of isoforms during seed development and germination both qualitatively and quantitatively. These advances have translated into relevant information about meaningful traits in seed breeding such as protein quality, longevity, gluten and allergen content, stress response and antifungal, antibacterial, and insect susceptibility. This review addresses progress on the biology of storage proteins and application areas in seed breeding using 2-DE-based maps.
Anticancer and Differentiation Properties of the Nitric Oxide Derivative of Lopinavir in Human Glioblastoma Cells
Authors: Basile Maria Sofia , Mazzon Emanuela , Krajnovic Tamara , Draca Dijana , Cavalli Eugenio , Al-Abed Yousef , Bramanti Placido , Nicoletti Ferdinando , Mijatovic Sanja , Maksimovic-Ivanic Danijela
Published: September 2018

Glioblastoma (GBM) is the most frequent and deadly form of primary malignant brain tumor among adults. A promising emerging approach for GBM treatment may be offered from HIV protease inhibitors (HIV-PIs). In fact, in addition to their primary pharmacological activity in the treatment of HIV infection, they possess important anti-neoplastic effects. According to previous studies, the addition of a nitric oxide (NO) donating group to parental compounds can reduce their toxicity and enhance the anticancer action of various compounds, including HIV-PIs. In this study we compared the effects of the HIV-PI Lopinavir (Lopi) and of its NO-derivative Lopinavir-NO (Lopi-NO) on the in vitro growth of LN-229 and U-251 human GBM cell lines. Lopi-NO reduced the viability of LN-229 and U-251 cells at significantly lower concentrations than the parental drug. In particular, Lopi-NO inhibited tumor cell proliferation and induced the differentiation of U-251 cells toward an astrocyte-like phenotype without triggering significant cell death in both cell types. The anticancer effect of Lopi-NO was persistent even upon drug removal. Furthermore, Lopi-NO induced strong autophagy that did not appear to be related to its chemotherapeutic action. Overall, our results suggest that Lopi-NO could be a potential effective anticancer drug for GBM treatment.
Spatial Overlap of Claudin- and Phosphatidylinositol Phosphate-Binding Sites on the First PDZ Domain of Zonula Occludens 1 Studied by NMR
Authors: Hiroaki Hidekazu , Satomura Kaori , Goda Natsuko , Nakakura Yukako , Hiranuma Minami , Tenno Takeshi , Hamada Daizo , Ikegami Takahisa
Published: September 2018

Background: The tight junction is an intercellular adhesion complex composed of claudins (CLDs), occludin, and the scaffolding proteins zonula occludens 1 (ZO-1) and its two paralogs ZO-2 and ZO-3. ZO-1 is a multifunctional protein that contains three PSD95/Discs large/ZO-1(PDZ) domains. A key functional domain of ZO-1 is the first PDZ domain (ZO-1(PDZ1)) that recognizes the conserved C-termini of CLDs. Methods: In this study, we confirmed that phosphoinositides bound directly to ZO-1(PDZ1) by biochemical and solution NMR experiments. We further determined the solution structure of mouse ZO-1(PDZ1) by NMR and mapped the phosphoinositide binding site onto its molecular surface. Results: The phosphoinositide binding site was spatially overlapped with the CLD-binding site of ZO-1(PDZ1). Accordingly, inositol-hexaphosphate (phytic acid), an analog of the phosphoinositide head group, competed with ZO-1(PDZ)-CLD interaction. Conclusions: The results suggested that the PDZ domain–phosphoinositide interaction plays a regulatory role in biogenesis and homeostasis of the tight junction.