bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bergenin inhibits bladder cancer progression via activating the PPARγ/PTEN/Akt signal pathway
Authors: Liu Junjiang , Zhang Yunxia , Yu Chunhong , Zhang Panying , Gu Shouyi , Wang Gang , Xiao Helong , Li Shoubin 
Published: October 2020

AbstractBladder cancer is one of the most common malignant tumors in the urinary system with high mortality and morbidity. Evidence revealed that bergenin could affect the development of cancer. Here, we aimed to investigate the effect of bergenin on bladder cancer progression and its mechanism. The effect of bergenin on cell function was first detected, followed by assessing the changes of the epithelial‐mesenchymal transition (EMT) in bergenin‐treated cells. The effect of bergenin on peroxisome proliferator‐activated receptor γ (PPARγ)/phosphatase and tensin homolog (PTEN)/Akt signal pathway was measured by Western blotting, followed by the rescue experiments. The results showed that bergenin treatment significantly decreased cell viability and increased G1 phase arrest, accompanied by reduced expression of Ki67, cycling D1, and cycling B1 in bladder cancer cells. Apoptosis was induced by bergenin in bladder cancer cells, as evidenced by increased Bax and cleaved caspase 3 protein levels and decreased Bcl‐2 level in bergenin‐treated cells. Meanwhile, the inhibition of the invasion, migration, and EMT was also observed in bergenin‐treated cells. Mechanism studies showed that bergenin treatment could activate PPARγ/PTEN/Akt signal pathway, as evidence by the increased nucleus PPARγ and phosphatase and tensin homolog (PTEN) expression and decreased Akt expression. Moreover, PPARγ inhibitor administration inverted the effects of bergenin on bladder cancer cell function, including the proliferation, apoptosis, invasion, and migration in bladder cancer cells. Our findings revealed that bergenin could inhibit bladder cancer progression via activating the PPARγ/PTEN/Akt signal pathway, indicating that bergenin may be a potential therapeutic medicine for bladder cancer treatment.
A review on nanotoxicity and nanogenotoxicity of different shapes of nanomaterials
Authors: Demir Eşref 
Published: October 2020

AbstractNanomaterials (NMs) generally display fascinating physical and chemical properties that are not always present in bulk materials; therefore, any modification to their size, shape, or coating tends to cause significant changes in their chemical/physical and biological characteristics. The dramatic increase in efforts to use NMs renders the risk assessment of their toxicity highly crucial due to the possible health perils of this relatively uncharted territory. The different sizes and shapes of the nanoparticles are known to have an impact on organisms and an important place in clinical applications. The shape of nanoparticles, namely, whether they are rods, wires, or spheres, is a particularly critical parameter to affect cell uptake and site‐specific drug delivery, representing a significant factor in determining the potency and magnitude of the effect. This review, therefore, intends to offer a picture of research into the toxicity of different shapes (nanorods, nanowires, and nanospheres) of NMs to in vitro and in vivo models, presenting an in‐depth analysis of health risks associated with exposure to such nanostructures and benefits achieved by using certain model organisms in genotoxicity testing. Nanotoxicity experiments use various models and tests, such as cell cultures, cores, shells, and coating materials. This review article also attempts to raise awareness about practical applications of NMs in different shapes in biology, to evaluate their potential genotoxicity, and to suggest approaches to explain underlying mechanisms of their toxicity and genotoxicity depending on nanoparticle shape.
Drain site enterocutaneous fistula after hyperthermic intraperitoneal chemotherapy
Authors: Kumar Navin , Lata Kanak , Ray Mukur Dipi 
Published: October 2020

AbstractSpontaneous sigmoid colon perforation after cytoreduction surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) is a rare complication. It is more commonly seen with mitomycin‐based HIPEC. This case study's patient presented with pus discharge at the drain site after 4 weeks of surgery. The symptoms persisted after conservative treatment. High suspicion after the feculent smell of the discharge fluidled to the prompt diagnosis of enterocutaneous fistula. There was limitedperforation with abscess formation, followed by fistula formation. The patient was treated successfully with surgery.
New pathogen, same disparities: why COVID‐19 and HIV remain prevalent in U.S. communities of colour and implications for ending the HIV epidemic
Authors: Millett Gregorio A 
Published: October 2020

AbstractIntroductionThe U.S. Ending the HIV Epidemic (EHE) Initiative was launched nationally in February 2019. With a target of ending the HIV epidemic by 2030, EHE initially scales up effective HIV prevention and care in 57 localities that comprise the greatest proportion of annual HIV diagnoses in the United States (US). However, the EHE effort has been eclipsed by another infectious disease 11 months into the Initiative’s implementation. SARS‐COV‐2, a novel coronavirus, has infected more than eight million Americans and at least 223 000 (as of 23 October 2020) have succumbed to the disease. This commentary explores the social conditions that place communities of colour at greater risk for COVID‐19 and HIV, and assesses challenges to EHE in a post‐COVID‐19 universe.DiscussionOne of the many common threads between HIV and COVID‐19 is the disproportionate impact of each disease among communities of colour. A recent report by the National Academy of Sciences surmised that as much as 70% of health outcomes are due to health access, socio‐economic factors and environmental conditions. Social determinants of health associated with greater HIV burden in Black and Brown communities have re‐emerged in epidemiological studies of disproportionate COVID‐19 cases, hospitalizations and deaths in communities of colour. Using data from the scientific literature, this commentary makes direct comparisons between HIV and COVID‐19 racial disparities across the social determinants of health. Furthermore, I examine three sets of challenges facing EHE: (1) Challenges that hamper both the EHE and COVID‐19 response (i.e. insufficiently addressing the social determinants of health; amplification of disparities as new health technologies are introduced) (2) Challenges posed by COVID‐19 (i.e. diverting HIV resources to address COVID‐19 and tapering of EHE funding generally); and (3) Challenges unrelated to COVID‐19 (i.e. emergence of new and related health disparities; repeal of the Affordable Care Act and long‐term viability of EHE).ConclusionsRacism and discrimination place communities of colour at greater risk for COVID‐19 as well as HIV. Achieving and sustaining an end to the U.S. HIV epidemic will require structural change to eliminate conditions that give rise to and maintain disparities.
Eliminating irreproducibility in SERS substrates
Authors: Grys David‐Benjamin , Chikkaraddy Rohit , Kamp Marlous , Scherman Oren A. , Baumberg Jeremy J. , de Nijs Bart 
Published: October 2020

AbstractIrreproducibility in surface‐enhanced Raman spectroscopy (SERS) due to variability among substrates is a source of recurrent debate within the field. It is regarded as a major hurdle towards the widespread adoption of SERS as a sensing platform. Most of the literature focused on developing substrates for various applications considers reproducibility of lower importance. Here, we address and analyse the sources of this irreproducibility in order to show how these can be minimised. We apply our findings to a simple substrate demonstrating reproducible SERS measurements with relative standard deviations well below 1% between different batches and days. Identifying the sources of irreproducibility and understanding how to reduce these can aid in the transition of SERS from the lab to real‐world applications.
Experimental tests of surface‐enhanced Raman scattering: Moving beyond the electromagnetic enhancement theory
Authors: Heeg Sebastian , Mueller Niclas S. , Wasserroth Sören , Kusch Patryk , Reich Stephanie 
Published: October 2020

AbstractThe electromagnetic enhancement theory describes surface‐enhanced Raman scattering (SERS) as a Raman effect that takes place in the near‐field of a plasmonic nanostructure. The theory has been very successful in explaining the fundamental properties of SERS, modelling the performance of different metals as enhancing materials and optimizing SERS hotspots for strongest possible enhancement. Over the last decade, a number of carefully designed experimental studies have examined predictions of the electromagnetic theory like the size and shape of SERS hotspots, the absolute magnitude of the enhancement and the width of the SERS resonance. Although the overall picture was quite satisfactory, the theory failed to predict key aspects of SERS, for example, the absolute magnitude of the plasmonic enhancement. We scrutinize these experiments and review them focusing on the results that require going beyond the electromagnetic enhancement theory. We argue that the results of these experiments create the need to develop the theory of SERS further, especially the exact role of plasmonic enhancement in inelastic light scattering.
Weak mineralization despite strong processing of dissolved organic matter in Eastern Arctic tundra ponds
Authors: Laurion Isabelle , Massicotte Philippe , Mazoyer Flora , Negandhi Karita , Mladenov Natalie 
Published: October 2020

AbstractPermafrost thawing mobilizes large quantities of organic carbon that was sequestered in Arctic regions over the last glacial cycle. Processes involved in the oxidation of this carbon need to be further assessed to estimate the fraction to be released into the atmosphere. Shallow tundra ponds are sites of active carbon turnover on the landscape and significant sources of greenhouse gases. Dissolved organic matter (DOM) leached from thawing peat into these ponds is exposed to sunlight, with the potential to accelerate its mineralization directly into CO2 or through the production of more labile molecules. We tested the catalytic effect of sunlight on DOM mineralization in tundra ponds formed on organic‐rich polygonal landscapes originating from syngenetic permafrost, including a pond exposed to active permafrost erosion. Microbial decay rates, measured as the loss of chromophoric DOM, were similar to photodecay rates (1%–3% d−1). Groups of fluorescing molecules were formed through microbial transformation or lost through photolysis at differing rates among studied ponds, with the erosive trough pond presenting a unique response suggesting the involvement of soil microbes. Despite the stimulation of microbial growth under sunlight and the dynamic response of DOM optical properties, the loss of dissolved organic carbon was not significant under any treatment. This suggests that microbial and photochemical mineralization of DOM was slow and potentially substrate‐limited during the dry period when ponds were sampled. The static nature of tundra ponds, with their long water retention time, may thus constrain hot moments when water moves and transports carbon on the landscape.
Requirements of LEFTY and Nodal overexpression for tumor cell survival under hypoxia in glioblastoma
Authors: Matsumoto Toshihide , Chino Hiromi , Akiya Masashi , Hashimura Miki , Yokoi Ako , Tochimoto Masataka , Nakagawa Mayu , Jiang Zesong , Saegusa Makoto 
Published: October 2020

AbstractGlioblastomas (GBM) contain numerous hypoxic foci associated with a rare fraction of glioma stem cells (GSCs). Left‐right determination factor (LEFTY) and Nodal, members of the transforming growth factor β (TGF‐β) superfamily, have glycogen synthase kinase 3β (GSK‐3β) phosphorylation motifs and are linked with stemness in human malignancies. Herein, we investigated the roles of LEFTY and Nodal in GBM hypoxic foci. In clinical samples, significantly higher expression of LEFTY, Nodal, phospho (p) GSK‐3β, pSmad2, and Nestin, as well as higher apoptotic and lower proliferation rates, were observed in nonpseudopalisading (non‐Ps) perinecrotic lesions as compared to Ps and non‐necrotic tumor lesions, with a positive correlation between LEFTY, Nodal, pGSK‐3β, or pSmad2 scores. In KS‐1, a GBM cell line that lacks endogenous Nodal expression, treatment with the hypoxic mimetic CoCl2 increased LEFTY, pGSK‐3β, and pSmad2 levels, but decreased pAkt levels. Moreover, the promoter for LEFTY, but not Nodal, was activated by Smad2 or TGF‐β1, suggesting that overexpression of LEFTY and Nodal may be due to Akt‐independent GSK‐3β inactivation, with or without cooperation of the TGF‐β1/Smad2 axis. LEFTY and Nodal overexpression increased proliferation rates and reduced susceptibility to CoCl2‐induced apoptosis, and increased the expression of epithelial‐mesenchymal transition (EMT)/GSC‐related markers. An increased ALDH1high population and more efficient spheroid formation was also observed in LEFTY‐overexpressing cells. These findings suggest that LEFTY and Nodal may contribute to cell survival in non‐Ps GBM perinecrotic lesions, leading to alterations in apoptosis, proliferation, or EMT/GCS features.
Spatial orthogonal attention generative adversarial network for MRI reconstruction
Authors: Zhou Wenzhong , Du Huiqian , Mei Wenbo , Fang Liping 
Published: October 2020

PurposeRecent studies have witnessed that self‐attention modules can better solve the vision understanding problems by capturing long‐range dependencies. However, there are very few works designing a lightweight self‐attention module to improve the quality of MRI reconstruction. Furthermore, it can be observed that several important self‐attention modules (e.g., the non‐local block) cause high computational complexity and need a huge number of GPU memory when the size of the input feature is large. The purpose of this study is to design a lightweight yet effective spatial orthogonal attention module (SOAM) to capture long‐range dependencies, and develop a novel spatial orthogonal attention generative adversarial network, termed as SOGAN, to achieve more accurate MRI reconstruction.MethodsWe first develop a lightweight SOAM, which can generate two small attention maps to effectively aggregate the long‐range contextual information in vertical and horizontal directions, respectively. Then, we embed the proposed SOAMs into the concatenated convolutional autoencoders to form the generator of the proposed SOGAN.ResultsThe experimental results demonstrate that the proposed SOAMs improve the quality of the reconstructed MR images effectively by capturing long‐range dependencies. Besides, compared with state‐of‐the‐art deep learning‐based CS‐MRI methods, the proposed SOGAN reconstructs MR images more accurately, but with fewer model parameters.ConclusionsThe proposed SOAM is a lightweight yet effective self‐attention module to capture long‐range dependencies, thus, can improve the quality of MRI reconstruction to a large extent. Besides, with the help of SOAMs, the proposed SOGAN outperforms the state‐of‐the‐art deep learning‐based CS‐MRI methods.
A variational formulation for motion design of adaptive compliant structures
Authors: Sachse Renate , Bischoff Manfred 
Published: October 2020

AbstractAdaptive structures are characterized by their ability to adjust their geometrical and other properties to changing loads or requirements during service. This contribution deals with a method for the design of quasi‐static motions of structures between two prescribed geometrical configurations that are optimal with regard to a specified quality function while taking large deformations into account. It is based on a variational formulation and the solution by two finite element discretizations, the spatial discretization (the standard finite element mesh) and an additional discretization of the deformation path or trajectory. For the investigations, an exemplary objective function, the minimization of the internal energy, integrated along the deformation path, is used. The method for motion design presented herein uses the Newton‐Raphson method as a second‐order optimization algorithm and allows for analytical sensitivity analysis. The proposed method is verified and its properties are investigated by benchmark examples including rigid body motions, instability phenomena, and determination of inextensible deformations of shells.
N‐Terminomics for the Identification of In Vitro Substrates and Cleavage Site Specificity of the SARS‐CoV‐2 Main Protease
Authors: Koudelka Tomas , Boger Juliane , Henkel Alessandra , Schönherr Robert , Krantz Stefanie , Fuchs Sabine , Rodríguez Estefanía , Redecke Lars , Tholey Andreas 
Published: October 2020

AbstractThe genome of coronaviruses, including SARS‐CoV‐2, encodes for two proteases, a papain like (PLpro) protease and the so‐called main protease (Mpro), a chymotrypsin‐like cysteine protease, also named 3CLpro or non‐structural protein 5 (nsp5). Mpro is activated by autoproteolysis and is the main protease responsible for cutting the viral polyprotein into functional units. Aside from this, it is described that Mpro proteases are also capable of processing host proteins, including those involved in the host innate immune response. To identify substrates of the three main proteases from SARS‐CoV, SARS‐CoV‐2, and hCoV‐NL63 coronviruses, an LC‐MS based N‐terminomics in vitro analysis is performed using recombinantly expressed proteases and lung epithelial and endothelial cell lysates as substrate pools. For SARS‐CoV‐2 Mpro, 445 cleavage events from more than 300 proteins are identified, while 151 and 331 Mpro derived cleavage events are identified for SARS‐CoV and hCoV‐NL63, respectively. These data enable to better understand the cleavage site specificity of the viral proteases and will help to identify novel substrates in vivo. All data are available via ProteomeXchange with identifier PXD021406.
Thermal unimolecular reactivity pathways in dehydro‐diazines radicals
Authors: Saraswat Mayank , Venkataramani Sugumar 
Published: October 2020

AbstractIn this work, we investigated the detailed reactivity of dehydro‐diazine radicals through unimolecular dissociation pathways. Aromatic six‐membered rings with two nitrogens as heteroatoms are classified as diazines, which include pyrimidine 1, pyridazine 2, and pyrazine 3. The C–H bond scission in pyrimidine, pyridazine, and pyrazine leads to three (1a–1c), two (2a and 2b), and one (3a) radical isomers, respectively. Through quantum chemical calculations, reactivity aspects of all the six radical isomers have been investigated by considering different modes of unimolecular reactions. On the basis of the computations at (U)B3LYP/cc‐pVTZ, (U)M06‐2X/cc‐pVTZ, and (U)CCSD(T)/cc‐pVTZ//(U)B3LYP/cc‐pVTZ levels of theory and analysis, we found out that ring‐opening pathways were kinetically more favorable compared with isomerization (1,2‐H shift) pathways or C–H bond dissociation leading to biradicals. In all the cases, ring‐opening via C–N bond cleavage has a lower energy barrier compared with C–C bond cleavage owing to the stabilizing interaction between radical electron and the nitrogen lone pair. Moreover, the unimolecular decomposition channels can lead to several fragmentation products, which are interesting in the astrochemical context. On the basis of these investigations and also the impact of three centered–five electrons (3c–5e) interactions on the reactivity aspects, we determined the kinetic stability order among the six isomeric dehydrodiazine radicals.
What we need to know to prevent a mass extinction of plant species
Authors: Pimm Stuart L. 
Published: October 2020

Social Impact StatementHuman actions are driving plant species to extinction at rates a hundred to a thousand times faster than normal. To prevent extinctions, it would be helpful to have a more comprehensive taxonomic catalogue and much greater knowledge of where plant species live. Addressing these questions must be a scientific priority. However, what we know at present is enough to effect practical conservation actions, such as protecting more land in biodiverse places, reconnecting fragmented habitats, and eliminating species introduced outside their native ranges. For the benefit of people and the planet, we can, and must act on what we know already, to prevent catastrophic plant extinctions.SummaryContinuing destruction of habitats—and especially tropical forests—the introduction of plant and herbivorous animal species outside their native ranges, and global climate disruption all contribute to the extinction of plant species. What can we do to prevent this? Do we have enough basic information to make effective conservation decisions? First, how many plant species are there? This question has an easy element—how many species we know now—and a much more difficult one—how many do we not know. Second, where are the concentrations of plant species? Third, where are the species we do not yet know? Fourth, what plant species have gone extinct, and where did they live? A related question is which species are threatened with extinction and where do they live? Fifth, how well can we map threats to species? For habitat loss, remote sensing provides satellite images globally and very frequently. It does so at a resolution that often displays individual trees and bushes. Sixth, supposing we had detailed answers to the previous questions, what are we doing to protect species? How well does the existing network of protected areas encompass species, especially those with the smallest ranges? Does that network allow for species moving upslope as the climate heats up? How well are managers doing in removing introduced species? Although answering these questions must be a scientific priority, we cannot wait until we have all the answers. We can, and indeed must, act on what we know already.
Enhancement of air stability and photovoltaic performance in organic solar cells by structural modulation of bis‐amide‐based donor‐acceptor copolymers: A computational insight
Authors: Bhattacharya Labanya , Sharma Sagar , Sahu Sridhar 
Published: October 2020

AbstractThe effect of structural modulation on a series of donor‐acceptor (D‐A) copolymers (1‐7), comprising of thieno[3,2‐b]thiophene (TT) donor and thiazole‐flanked different bis‐amide‐functionalized acceptor units, has been explored. Structural functionalization has been performed by incorporating aromatic rings in the bis‐amide‐functionalized bipyrrolylidene‐2,2′(1H,1′H)‐dione (BPD) (1) acceptor unit, and six D‐A copolymers containing isoindigo (2), azaisoindigo (3), benzoisoindigo (4), benzoazaisoindigo (5), 1,5‐naphthyridine‐BPD (6), and 1,8‐naphthyridine‐BPD (7) as acceptor units are designed. Density functional theory has been employed to understand the impact of structural modulation on geometrical, optoelectronic, charge transport, and photovoltaic properties of the copolymers. The higher proportion of N‐heteroatom in copolymers 3, 6, and 7 leads to low‐lying highest occupied molecular orbital (lowest unoccupied molecular orbital) levels and thus improves their air stability and open‐circuit voltage. The computed optical absorption in the visible range (602‐754 nm) ensures that the studied compounds can efficiently harvest photon energy. The ratio of charge transfer rate (KCT) and charge recombination rate (KCR) at donor/PC61BM interfaces of structurally tuned copolymers are found to be ∼107 to 1022 times higher than 1/PC61BM. The maximum predicted power conversion efficiency by Scharber diagram could reach up to ∼8% for 3, 6, and 7. The calculated results shed light on the fact that the structural modulation of bis‐amide‐functionalized D‐A copolymers can efficaciously lead to enhanced air stability and photovoltaic performance.