bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Contribution of Symbiodinium Microadriaticum to the Symbiosome Membrane in the Anthozoan Host Aiptasia Pallida
Authors: Wakefield Timothy S , Kempf Stephen C , Farmer Mark A 
Published: July 2020

Abstract
Most endosymbionts remain separated from their host cell by a derivative of the phagocytic membrane. This membrane and its contents have been defined as a novel “organelle-like” structure called a symbiosome. However, in the case of many cnidarian-dinoflagellate symbioses the putative symbiosome is composed of multiple layers of apparent membranes (Fig. 1). In the past the origin of these membranes has been assigned to host and/or symbiont with very little experimental evidence to support either view; however, several interesting hypotheses have been proposed to explain the origin of the “membranes”. Trench and Blank suggest that occasionally the outer most layer of the vegetative symbiont's cell wall is sloughed off the surface of the cell. They concede that the outer most layer of “membranes” must be the host vacuolar membrane, but believe that it simply prevents the sloughed layer from moving away from the cell, (as would happen in culture), and that, over time, multiple sloughed layers accumulate beneath the host vacular membrane.
Amino Acid Composition and Immunolabelling of a 42.5 KDA Protein from Phloem Exudate of Luffa Cylindrica Fruits
Authors: Wang M C , Chen Y R 
Published: July 2020

Abstract
Phloem proteins are specifically presented in phloem tissues of monocotyledons and dicotyledons. Ultrastructural studies showed that they were filamentous, spherical, tubular, crystalline and amorphous in shaped They were present in the sieve elements and sometimes are also found in companion cells and phloem parenchyma cells. The diversities in shape and biogenesis of plant p-protein in relation to plant species and developmental stage of phloem tissues were reported. In the present study, a 42.5 kDA protein obtained from phloem exudate of Luffa cylindrica fruits were examined with amino acid composition, immnoblotting, and immunolocalization.
Phloem exudates leaking from Luffa cylindrica fruits by a simple razor blade cutting were mixed with the extraction medium containing antioxidant and rapidly separated by 2-dimensional gel of native and sodium dodecylsulfate (SDS) polyacrylamide gel electrophoresis (PAGE).
Recognizing Sample-Selection Bias in Historical Data
Authors: Zimran Ariell 
Published: July 2020

ABSTRACTRecent research has ignited a debate in social science history over whether and how to draw conclusions for whole populations from sources that describe only select subsets of these populations. The idiosyncratic availability and survival of historical sources create a threat of sample-selection bias—an error that arises when there are systematic differences between the observed sample and the population of interest. This danger is common in studying trends in health as measured by average stature—scholars can often observe these trends only for soldiers and other similar groups; but whether these patterns are representative of those of the broader population is unclear. This article illustrates what simple patterns in a potentially selected sample can be used to recognize the presence of sample-selection bias in a source, and to understand how such bias might affect conclusions drawn from this source. Applying this intuition to the use of military data to describe stature in the antebellum United States, I present several simple empirical exercises based on these patterns. Finally, I use the results of these exercises to describe how sample-selection bias might affect the use of these data in testing for differences in average stature between the Northeast and the Midwest.
Coupled Time‐Lapse Full‐Waveform Inversion for Subsurface Flow Problems Using Intrusive Automatic Differentiation
Authors: Li Dongzhuo , Xu Kailai , Harris Jerry M. , Darve Eric 
Published: July 2020

AbstractWe describe a novel framework for estimating subsurface properties, such as rock permeability and porosity, from time‐lapse observed seismic data by coupling full‐waveform inversion (FWI), subsurface flow processes, and rock physics models. For the inverse modeling, we handle the back propagation of gradients by an intrusive automatic differentiation strategy that offers three levels of user control: (1) At the wave physics level, we adopted the discrete adjoint method in order to use our existing high‐performance FWI code; (2) at the rock physics level, we used built‐in automatic differentiation operators from the TensorFlow backend; (3) at the flow physics level, we implemented customized partial differential equation (PDE) operators for the multiphase flow equations. The three‐level coupled inversion strategy strikes a good balance between computational efficiency and programming efforts, and when the gradients are chained together, it constitutes a coupled inverse system. Our numerical experiments demonstrate that the three‐level coupled inverse problem is superior in terms of accuracy to a traditional decoupled inversion strategy. Additionally, our method is able to simultaneously invert for parameters in empirical relationships such as the rock physics models. Our proposed inverted model can be used for reservoir performance prediction and reservoir management/optimization purposes.
Subduction Initiation by Plume‐Plateau Interaction: Insights From Numerical Models
Authors: Baes Marzieh , Sobolev Stephan V. , Gerya Taras , Brune Sascha 
Published: July 2020

AbstractIt has recently been demonstrated that the interaction of a mantle plume with sufficiently old oceanic lithosphere can initiate subduction. However, the existence of large lithospheric heterogeneities, such as a buoyant plateau, in proximity to a rising plume head may potentially hinder the formation of a new subduction zone. Here, we investigate this scenario by means of 3‐D numerical thermomechanical modeling. We explore how plume‐lithosphere interaction is affected by lithospheric age, relative location of plume head and plateau border, and the strength of the oceanic crust. Our numerical experiments suggest four different geodynamic regimes: (a) oceanic trench formation, (b) circular oceanic‐plateau trench formation, (c) plateau trench formation, and (d) no trench formation. We show that regardless of the age and crustal strength of the oceanic lithosphere, subduction can initiate when the plume head is either below the plateau border or at a distance less than the plume radius from the plateau edge. Crustal heterogeneity facilitates subduction initiation of old oceanic lithosphere. High crustal strength hampers the formation of a new subduction zone when the plume head is located below a young lithosphere containing a thick and strong plateau. We suggest that plume‐plateau interaction in the western margin of the Caribbean could have resulted in subduction initiation when the plume head impinged onto the oceanic lithosphere close to the border between plateau and oceanic crust.
Ionospheric and Magnetic Signatures of a Space Weather Event on 25–29 August 2018: CME and HSSWs
Authors: Younas W. , Amory‐Mazaudier C. , Khan Majid , Fleury R. 
Published: July 2020

AbstractWe present a study concerning a space weather event on 25–29 August 2018, accounting for its ionospheric and magnetic signatures at low latitudes and midlatitudes. The effects of a storm in several longitudinal sectors (Asia, Africa, America, and the Pacific) have been analyzed using various parameters such as total electron content (TEC), geomagnetic field, and column [O/N2] ratio. Positive ionospheric storms are found in all the longitudinal sectors having its maximum effects in the Asian sector, whereas the negative ionospheric storms have been observed in the summer hemisphere (Northern Hemisphere). A large decrease in [O/N2] ratio in the Northern Hemisphere is a possible cause of the observed negative storm effects. Ionospheric F2 region maximum electron density (NmF2) and TEC have shown a positive correlation during this storm. The study suggests that storm time‐generated wind does not have a uniform planetary extension and mainly affects dayside (America and Pacific) and duskside (Africa) sectors. During the space weather event, we observe an asymmetric variation of the magnetic field as a function of the longitude. On the other hand, the magnetic variations at midlatitudes are found to be symmetric in both hemispheres. A signature of the disturbance dynamo (anti‐Sq circulation) has been observed, mainly at low latitudes. We emphasize that the partial ring current (PRC), estimated by the ASYM‐H magnetic index, must also be taken into account along with the SYM‐H index for a better approximation of ionospheric currents. The study further suggests existence of several electric current cells in the ionosphere, which is consistent with the Blanc‐Richmond model.
Dexmedetomidine promotes the progression of hepatocellular carcinoma through hepatic stellate cell activation
Authors: Chen Peng , Luo Xiaojun , Dai Guanqi , Jiang Yuchuan , Luo Yue , Peng Shuang , Wang Hao , Xie Penghui , Qu Chen , Lin Wenyu , Hong Jian , Ning Xue , Li Aimin 
Published: July 2020

AbstractDexmedetomidine (DEX) is an anesthetic that is widely used in the clinic, and it has been reported to exhibit paradoxical effects in the progression of multiple solid tumors. In this study, we sought to explore the mechanism by which DEX regulates hepatocellular carcinoma (HCC) progression underlying liver fibrosis. We determined the effects of DEX on tumor progression in an orthotopic HCC mouse model of fibrotic liver. A coculture system and a subcutaneous xenograft model involving coimplantation of mouse hepatoma cells (H22) and primary activated hepatic stellate cells (aHSCs) were used to study the effects of DEX on HCC progression. We found that in the preclinical mouse model of liver fibrosis, DEX treatment significantly shortened median survival time and promoted tumor growth, intrahepatic metastasis and pulmonary metastasis. The DEX receptor (ADRA2A) was mainly expressed in aHSCs but was barely detected in HCC cells. DEX dramatically reinforced HCC malignant behaviors in the presence of aHSCs in both the coculture system and the coimplantation mouse model, but DEX alone exerted no significant effects on the malignancy of HCC. Mechanistically, DEX induced IL-6 secretion from aHSCs and promoted HCC progression via STAT3 activation. Our findings provide evidence that the clinical application of DEX may cause undesirable side effects in HCC patients with liver fibrosis.
Evolutionary compromises in fungal fitness: hydrophobins can hinder the adverse dispersal of conidiospores and challenge their survival
Authors: Cai Feng , Gao Renwei , Zhao Zheng , Ding Mingyue , Jiang Siqi , Yagtu Civan , Zhu Hong , Zhang Jian , Ebner Thomas , Mayrhofer-Reinhartshuber Michael , Kainz Philipp , Chenthamara Komal , Akcapinar Günseli Bayram , Shen Qirong , Druzhinina Irina S 
Published: July 2020

Abstract
Fungal evolutionary biology is impeded by the scarcity of fossils, irregular life cycles, immortality, and frequent asexual reproduction. Simple and diminutive bodies of fungi develop inside a substrate and have exceptional metabolic and ecological plasticity, which hinders species delimitation. However, the unique fungal traits can shed light on evolutionary forces that shape the environmental adaptations of these taxa. Higher filamentous fungi that disperse through aerial spores produce amphiphilic and highly surface-active proteins called hydrophobins (HFBs), which coat spores and mediate environmental interactions. We exploited a library of HFB-deficient mutants for two cryptic species of mycoparasitic and saprotrophic fungi from the genus Trichoderma (Hypocreales) and estimated fungal development, reproductive potential, and stress resistance. HFB4 and HFB10 were found to be relevant for Trichoderma fitness because they could impact the spore-mediated dispersal processes and control other fitness traits. An analysis in silico revealed purifying selection for all cases except for HFB4 from T. harzianum, which evolved under strong positive selection pressure. Interestingly, the deletion of the hfb4 gene in T. harzianum considerably increased its fitness-related traits. Conversely, the deletion of hfb4 in T. guizhouense led to the characteristic phenotypes associated with relatively low fitness. The net contribution of the hfb4 gene to fitness was found to result from evolutionary tradeoffs between individual traits. Our analysis of HFB-dependent fitness traits has provided an evolutionary snapshot of the selective pressures and speciation process in closely related fungal species.
Spermidine activates RIP1 deubiquitination to inhibit TNF-α-induced NF-κB/p65 signaling pathway in osteoarthritis
Authors: Chen Zhong , Lin Chuang-Xin , Song Bin , Li Chang-Chuan , Qiu Jun-Xiong , Li Shi-Xun , Lin Si-Peng , Luo Wen-Qiang , Fu Yuan , Fang Gui-Bin , Wei-Ping Li , Saw Phei Er , Ding Yue 
Published: July 2020

AbstractSpermidine has been known to inhibit the production of pro-inflammatory cytokines. However, there are no reports about anti-inflammatory effects of spermidine on osteoarthritis (OA). Herein, we examined whether OA progression could be delayed by intraperitoneal injection (i.p.) of spermidine in the anterior cruciate ligament transection (ACLT) and TNF-α induced arthritis (TIA) mouse models. During the process, human FLS cells (H-FLS) were used to investigate the potential ubiquitination mechanism of spermidine-mediated RIP1 in TNF-α-induced NF-κB/p65 signaling. We found that spermidine attenuated synovitis, cartilage degeneration and osteophyte formation, resulting in substantially lower OARSI scores and TNF-α scores in spermidine-treated ACLT and TIA mice. In terms of the mechanism, 9 μM spermidine did not affect the viability, proliferation, cell cycle and apoptosis of H-FLS, and exerted inhibitory effects by activating CYLD-mediated RIP1 deubiquitination on TNF-α-induced NF-κB/p65 signaling in H-FLS. From these data, we can conclude that spermidine attenuates OA progression by the inhibition of TNF-α-induced NF-κB pathway via the deubiquitination of RIP1 in FLS. Therefore, intake of spermidine could be a potential therapy for preventing OA.
Metabolic and psychiatric effects of acyl coenzyme A binding protein (ACBP)/diazepam binding inhibitor (DBI)
Authors: Joseph Adrien , Moriceau Stéphanie , Sica Valentina , Anagnostopoulos Gerasimos , Pol Jonathan , Martins Isabelle , Lafarge Antoine , Maiuri Maria Chiara , Leboyer Marion , Loftus Josephine , Bellivier Frank , Belzeaux Raoul , Berna Fabrice , Etain Bruno , Capdevielle Delphine , Courtet Philippe , Dubertret Caroline , Dubreucq Julien , Thierry D’. Amato , Fond Guillaume , Gard Sebastien , Llorca Pierre-Michel , Mallet Jasmina , Misdrahi David , Olié Emilie , Passerieux Christine , Polosan Mircea , Roux Paul , Samalin Ludovic , Schürhoff Franck , Schwan Raymond ,   the FACE-SZ and FACE-BD (FondaMental Academic Centers of Expertise, for Schizophrenia and for Bipolar Disorder) Groups, Magnan Christophe , Oury Franck , Bravo-San Pedro José M. , Kroemer Guido 
Published: July 2020

AbstractAcyl coenzyme A binding protein (ACBP), also known as diazepam binding inhibitor (DBI) is a multifunctional protein with an intracellular action (as ACBP), as well as with an extracellular role (as DBI). The plasma levels of soluble ACBP/DBI are elevated in human obesity and reduced in anorexia nervosa. Accumulating evidence indicates that genetic or antibody-mediated neutralization of ACBP/DBI has anorexigenic effects, thus inhibiting food intake and inducing lipo-catabolic reactions in mice. A number of anorexiants have been withdrawn from clinical development because of their side effects including an increase in depression and suicide. For this reason, we investigated the psychiatric impact of ACBP/DBI in mouse models and patient cohorts. Intravenously (i.v.) injected ACBP/DBI protein conserved its orexigenic function when the protein was mutated to abolish acyl coenzyme A binding, but lost its appetite-stimulatory effect in mice bearing a mutation in the γ2 subunit of the γ-aminobutyric acid (GABA) A receptor (GABAAR). ACBP/DBI neutralization by intraperitoneal (i.p.) injection of a specific mAb blunted excessive food intake in starved and leptin-deficient mice, but not in ghrelin-treated animals. Neither i.v. nor i.p. injected anti-ACBP/DBI antibody affected the behavior of mice in the dark–light box and open-field test. In contrast, ACBP/DBI increased immobility in the forced swim test, while anti-ACBP/DBI antibody counteracted this sign of depression. In patients diagnosed with therapy-resistant bipolar disorder or schizophrenia, ACBP/DBI similarly correlated with body mass index (BMI), not with the psychiatric diagnosis. Patients with high levels of ACBP/DBI were at risk of dyslipidemia and this effect was independent from BMI, as indicated by multivariate analysis. In summary, it appears that ACBP/DBI neutralization has no negative impact on mood and that human depression is not associated with alterations in ACBP/DBI concentrations.
Activating PIK3CA mutation promotes osteogenesis of bone marrow mesenchymal stem cells in macrodactyly
Authors: Cui Hengqing , Han Gang , Sun Bin , Fang Xia , Dai Xinyi , Zhou Shengbo , Mao Hailei , Wang Bin 
Published: July 2020

AbstractMacrodactyly is a disabling congenital disease characterized by overgrowth of soft tissues and bones, which leads to finger enlargement and joint deformity. The mechanism of bone overgrowth in macrodactyly was rarely understood. In our study bone manifestations of three macrodactyly patients were analyzed by micro-CT. PIK3CA mutation was detected by next-generation sequencing (NGS) of a tumor gene-panel. The PI3K/AKT/mTOR pathway activation and target genes were analyzed. The osteogenic potential of macrodactyly-derived bone marrow mesenchymal stem cells (MAC-BMSCs) was compared with polydactyly-derived bone marrow mesenchymal stem cells (PD-BMSCs). PIK3CA inhibitors were tested for proliferation and osteogenesis potential of MAC-BMSCs. Activating PIK3CA mutations and activation of PI3K/AKT/mTOR pathway were detected in all MAC-BMSCs. MAC-BMSCs had enhanced osteogenesis potential compared with PD-BMSCs. PIK3CA knockdown by shRNA or BYL719 treatment significantly reduced osteogenic differentiation capacity of MAC-BMSCs. RNA-Seq and qRT-PCR revealed the upregulation of distal-less homeobox 5 (DLX5) in MAC-BMSCs compared with PD-BMSCs. The osteogenic potential of MAC-BMSCs was inhibited by DLX5 knockdown, indicating that DLX5 is a downstream target of PIK3CA activation-mediated osteogenesis. This study revealed that osteogenic differentiation in MAC-BMSCs is enhanced by PIK3CA activation mutation through PI3K/AKT/mTOR signaling pathway and can be reversed by PIK3CA knockdown or drug inhibition.
AMG-232 sensitizes high MDM2-expressing tumor cells to T-cell-mediated killing
Authors: Sahin Ilyas , Zhang Shengliang , Navaraj Arunasalam , Zhou Lanlan , Dizon Don , Safran Howard , El-Deiry Wafik S. 
Published: July 2020

AbstractOncogenic mouse double minute 2 homolog (MDM2) is an E3-ubiquitin ligase that facilitates proteasomal degradation of p53. MDM2 amplification occurs in cancer and has been implicated in accelerated tumor growth, known as hyper-progression, following immune-checkpoint therapy. MDM2 amplification also predicts poor response to immune-checkpoint inhibitors. We sought to evaluate the role of MDM2 in T-cell-mediated immune resistance. Ovarian clear cell carcinoma cell lines carrying wild-type p53 with low/high MDM2 expression were investigated in a T-cell co-culture system evaluating T-cell-mediated tumor killing. Targeting of MDM2 was achieved by siRNA transfection or a selective MDM2 inhibitor, AMG-232 and tumor cells were tested in the T-cell co-culture system. AMG-232 activated p53 signaling in cancer cells and relative resistance to AMG-232 was observed in high MDM2-expressing cell lines. Cell lines with high MDM2 expression were more resistant to T cell-mediated tumor killing. Targeting MDM2 by gene-silencing or pharmacological blockade with AMG-232 enhanced T-cell killing of cancer cells. AMG-232 potentiated tumor cell killing by T-cells in combination with anti-PD-1 antibody treatment, regardless of changes in PD-L1 expression. The AMG-232 was not toxic to the T-cells. MDM2 inhibition lowered expression of Interleukin-6, a pro-inflammatory pro-tumorigenic cytokine. Our data support targeting MDM2 in tumors with overexpression or amplification of MDM2 as a precision therapy approach to overcome drug resistance including hyper-progression in the context of immune checkpoint therapy.
Self-assembled dodecyl group-modified gelatin microparticle-based hydrogels with angiogenic properties
Authors: Mizuno Yosuke , Taguchi Tetsushi 
Published: July 2020

AbstractSupplying oxygen and nutrients to implanted cells or tissues is an important factor that improves their survivability and function in regenerative medicine. Various efforts have been made to develop angiogenic materials by incorporating and releasing growth factors such as vascular endothelial growth factor (VEGF). However, these exogenous growth factors have a short half-life under physiological conditions. We therefore designed a novel angiogenic microparticle (C12-MP) comprising Alaska pollock-derived gelatin (ApGltn) modified with a dodecyl group (C12-ApGltn) to stimulate endogenous VEGF secretion. The C12-MP suspension formed an injectable hydrogel, the rheological properties and enzymatic degradation of which were evaluated. RAW264 cells, mouse macrophage-like cells, cultured with C12-MPs, secreted significantly more VEGF than the original ApGltn MPs. Based on laser Doppler perfusion imaging, the C12-MP hydrogel clearly induced increased blood perfusion in a subcutaneous mouse model compared with the original ApGltn microparticle (Org-MP) or phosphate-buffered saline controls. Histological studies revealed that the areas of nuclear factor (NF)-κB, CD31, and myeloperoxidase staining showed a greater increase at the site injected with C12-MPs than at the site injected with the original ApGltn microparticles or phosphate-buffered saline. The C12-MP hydrogel is a promising angiogenic material for constructing vascular beds for cell transplantation by promoting endogenous VEGF secretion without additional growth factors.
Rapid geomagnetic changes inferred from Earth observations and numerical simulations
Authors: Davies Christopher J. , Constable Catherine G. 
Published: July 2020

AbstractExtreme variations in the direction of Earth’s magnetic field contain important information regarding the operation of the geodynamo. Paleomagnetic studies have reported rapid directional changes reaching 1° yr−1, although the observations are controversial and their relation to physical processes in Earth’s core unknown. Here we show excellent agreement between amplitudes and latitude ranges of extreme directional changes in a suite of geodynamo simulations and a recent observational field model spanning the past 100 kyrs. Remarkably, maximum rates of directional change reach ~10° yr−1, typically during times of decreasing field strength, almost 100 times faster than current changes. Detailed analysis of the simulations and a simple analogue model indicate that extreme directional changes are associated with movement of reversed flux across the core surface. Our results demonstrate that such rapid variations are compatible with the physics of the dynamo process and suggest that future searches for rapid directional changes should focus on low latitudes.