bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synchronous, Crosstalk-free Correlative AFM and Confocal Microscopies/Spectroscopies
Authors: Fernandes Thales F. D. , Saavedra-Villanueva Oscar , Margeat Emmanuel , Milhiet Pierre-Emmanuel , Costa Luca 
Published: April 2020

AbstractMicroscopies have become pillars of our characterization tools to observe biological systems and assemblies. Correlative and synchronous use of different microscopies relies on the fundamental assumption of non-interference during images acquisitions. In this work, by exploring the correlative use of Atomic Force Microscopy and confocal-Fluorescence-Lifetime Imaging Microscopy (AFM-FLIM), we quantify cross-talk effects occurring during synchronous acquisition. We characterize and minimize optomechanical forces on different AFM cantilevers interfering with normal AFM operation as well as spurious luminescence from the tip and cantilever affecting time-resolved fluorescence detection. By defining non-interfering experimental imaging parameters, we show accurate real-time acquisition and two-dimensional mapping of interaction force, fluorescence lifetime and intensity characterizing morphology (AFM) and local viscosity (FLIM) of gel and fluid phases separation of supported lipid model membranes. Finally, as proof of principle by means of synchronous force and fluorescence spectroscopies, we precisely tune the lifetime of a fluorescent nanodiamond positioned on the AFM tip by controlling its distance from a metallic surface. This opens up a novel pathway of quench sensing to image soft biological samples such as membranes since it does not require tip-sample mechanical contact in contrast with conventional AFM in liquid.
Opposing roles of hematopoietic-specific small GTPase Rac2 and the guanine nucleotide exchange factor Vav1 in osteoclast differentiation
Authors: Kang In Soon , Jang Jin Sun , Kim Chaekyun 
Published: April 2020

AbstractVav1 regulates Rac activation as a hematopoietic-specific Rho/Rac-family guanine nucleotide exchange factor. Rac is a subfamily of Rho GTPases that regulates the bone-resorbing capacity of osteoclasts (OCs). In this study, we show that hematopoietic-specific Rac2 and Vav1 play opposing roles by enhancing or attenuating OC differentiation, respectively. This was demonstrated by higher and lower bone density in the femurs from Rac2-deficient (Rac2−/−) and Vav1-deficient (Vav1−/−) mice, respectively, compared to the wild-type (WT) mice. Accordingly, Rac2−/− cells displayed low numbers of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (41%) compared to WT cells, whereas, Vav1−/− cells showed high TRAP-positive cell numbers (150%), and the double-knockout Rac2−/−Vav1−/− mice nullified the effects on OC numbers achieved by the individual knockouts. These reciprocal roles of Rac2 and Vav1 in OC differentiation were confirmed by reduced and increased levels of OC-specific markers, such as TRAP, calcitonin receptor, cathepsin K, and DC-STAMP in the Rac2−/− and Vav1−/− OCs, respectively. Our findings of decrease and increase in actin ring formation and αvβ3 integrin-mediated adhesion in Rac2−/− and Vav1−/− mice, respectively, suggest that Vav1 and its downstream GTPase, Rac2, may counteract to fine-tune OC differentiation and bone resorption.
The 2018 periodontitis case definition improves accuracy performance of full-mouth partial diagnostic protocols
Authors: Botelho João , Machado Vanessa , Proença Luís , Mendes José João 
Published: April 2020

AbstractWe aimed to compare the accuracy performance of the new 2018 periodontitis case definition by the European Federation of Periodontology (EFP)/ American Association of Periodontology (AAP) with Centers for Disease Control (CDC)/AAP 2012 in full-mouth partial recording protocols (PRP). Retrospective data from NHANES 2011-2012 and 2013-2014 were analyzed. For each case definition, full-mouth diagnostic was defined as the reference standard. Patients were diagnosed for the presence of periodontitis and staging for each PRP. Sensitivity, specificity, accuracy and precision, through several indicators, were determined. Performance measurement was assessed through binary and multiclass ROC/AUC analyses. Our performance analysis shows that the new 2018 classification outperforms the 2012 classification regarding the diagnosis and staging of periodontitis on full-mouth PRPs. This recent case definition has strengthened the utility of PRPs and its improvements certainly explain the observed findings. Also, our findings contribute to the reliability of PRPs and its use in future worldwide epidemiological surveys.
Graphene Quantum Dot Oxidation Governs Noncovalent Biopolymer Adsorption
Authors: Jeong Sanghwa , Pinals Rebecca L. , Dharmadhikari Bhushan , Song Hayong , Kalluri Ankarao , Debnath Debika , Wu Qi , Ham Moon-Ho , Patra Prabir , Landry Markita P. 
Published: April 2020

AbstractGraphene quantum dots (GQDs) are an allotrope of carbon with a planar surface amenable to functionalization and nanoscale dimensions that confer photoluminescence. Collectively, these properties render GQDs an advantageous platform for nanobiotechnology applications, including optical biosensing and delivery. Towards this end, noncovalent functionalization offers a route to reversibly modify and preserve the pristine GQD substrate, however, a clear paradigm has yet to be realized. Herein, we demonstrate the feasibility of noncovalent polymer adsorption to GQD surfaces, with a specific focus on single-stranded DNA (ssDNA). We study how GQD oxidation level affects the propensity for polymer adsorption by synthesizing and characterizing four types of GQD substrates ranging ~60-fold in oxidation level, then investigating noncovalent polymer association to these substrates. Adsorption of ssDNA quenches intrinsic GQD fluorescence by 31.5% for low-oxidation GQDs and enables aqueous dispersion of otherwise insoluble no-oxidation GQDs. ssDNA-GQD complexation is confirmed by atomic force microscopy, by inducing ssDNA desorption, and with molecular dynamics simulations. ssDNA is determined to adsorb strongly to no-oxidation GQDs, weakly to low-oxidation GQDs, and not at all for heavily oxidized GQDs. Finally, we reveal the generality of the adsorption platform and assess how the GQD system is tunable by modifying polymer sequence and type.
A spatio-temporal analysis to identify the drivers of malaria transmission in Bhutan
Authors: Wangdi Kinley , Xu Zhijing , Suwannatrai Apiporn T. , Kurscheid Johanna , Lal Aparna , Namgay Rinzin , Glass Kathryn , Gray Darren J. , Clements Archie C. A. 
Published: April 2020

AbstractAt a time when Bhutan is on the verge of malaria elimination, the aim of this study was to identify malaria clusters at high geographical resolution and to determine its association with local environmental characteristics. Malaria cases from 2006–2014 were obtained from the Vector-borne Disease Control Program under the Ministry of Health, Bhutan. A Zero-Inflated Poisson multivariable regression model with a conditional autoregressive (CAR) prior structure was developed. Bayesian Markov chain Monte Carlo (MCMC) simulation with Gibbs sampling was used to estimate posterior parameters. A total of 2,062 Plasmodium falciparumand 2,284 Plasmodium vivaxcases were reported during the study period. Both species of malaria showed seasonal peaks with decreasing trend. Gender and age were not associated with the transmission of either species of malaria.P. falciparumincreased by 0.7% (95% CrI: 0.3%, 0.9%) for a one mm increase in rainfall, while climatic variables (temperature and rainfall) were not associated withP. vivax. Insecticide treated bed net use and residual indoor insecticide coverage were unaccounted for in this study. Hot spots and clusters of both species were isolated in the central southern part of Bhutan bordering India. There was significant residual spatial clustering after accounting for climate and demographic variables.
Neonicotinoids suppress contact chemoreception in a common farmland spider
Authors: Korenko Stanislav , Sýkora Jakub , Řezáč Milan , Heneberg Petr 
Published: April 2020

AbstractNeonicotinoid insecticides are increasingly recognized for their role as information disruptors by modifying the chemical communication system of insects and therefore decreasing the chances of reproduction in target insects. However, data from spiders are lacking. In the present study, we tested the responses of males of a common agrobiont spider, Pardosa agrestis, to the application of field-realistic concentration of acetamiprid, which was formulated as Mospilan, and trace amounts of thiacloprid, which was formulated as Biscaya. We applied fresh or 24-h-old residues of Mospilan or Biscaya to the males just prior to the experiment or treated only the surface of a tunnel containing female draglines. We evaluated the ability of the males to recognize female cues from female dragline silk in a Y-maze. The field-realistic, sublethal doses of Mospilan altered pheromone-guided behavior. The choice of the tunnel with female draglines by males was hampered by tarsal treatment of the males with 24 h-old residues of Mospilan. The mating dance display was commonly initiated in control males that came into contact with female draglines and was suppressed by the Mospilan treatments in all three experimental settings. Some males only initiated the mating dance but did not manage to complete it; this was particularly true for males that were treated tarsally with fresh Mospilan residues, as none of these males managed to complete the mating dance. All three experimental settings with Mospilan decreased the frequency of males that managed to both select the tunnel with female draglines and complete the mating dance. The responses to the low-dose Biscaya were much milder and the study was not sufficiently powered to confirm the effects of Biscaya; however, the surprisingly observed trends in responses to very low Biscaya concentrations call for further analyses of long-term effects of trace amounts of neonicotinoids on the pheromone-guided behavior of spiders. These are the first conclusive data regarding the effects of commercially available formulations of neonicotinoid insecticides on the intraspecific chemical communication of spiders.
Nectar mimicry: a new phenomenon
Authors: Lunau Klaus , Ren Zong-Xin , Fan Xiao-Qing , Trunschke Judith , Pyke Graham H. , Wang Hong 
Published: April 2020

AbstractNectar is the most common floral reward for flower-visiting flies, bees, bats and birds. Many flowers hide nectar in the floral tube and preclude sensing of nectar by flower-visitors from a distance. Even in those flowers that offer easily accessible nectar, the nectaries are mostly inconspicuous to the human eye and the amount of nectar is sparse. It is widely accepted that many flowers display nectar guides in order to direct flower-visitors towards the nectar. Using false colour photography, covering ultraviolet, blue and green ranges of wavelength, revealed a yet unknown conspicuousness of nectar, nectaries and false nectaries for bees due to concordant reflection in the ultraviolet range of wavelength. Nectars, many nectaries and false nectaries have glossy surfaces and reflect all incident light including UV-light. In most cases, this is not particularly conspicuous to the human eye, but highly visible for UV-sensitive insects, due to the fact that the glossy areas are often positioned in UV-absorbing central flower parts and thus produce a strong UV-signal. The optical contrast produced by the glossiness of small smooth areas in close proximity to nectar holders represents a widespread yet overlooked floral cue that nectarivorous flower-visitors might use to locate the floral nectar.
Dietary Patterns Associated to Clinical Aspects in Crohn’s Disease Patients
Authors: de Castro Marina Moreira , Corona Ligiana Pires , Pascoal Lívia Bitencourt , Miyamoto Josiane Érica , Ignacio-Souza Leticia Martins , de Lourdes Setsuko Ayrizono Maria , Torsoni Marcio Alberto , Torsoni Adriana Souza , Leal Raquel Franco , Milanski Marciane 
Published: April 2020

AbstractDiet is an important factor in both the pathogenesis and in the clinical course of Crohn’s disease (CD). However, data on dietary patterns of CD patients are rather limited in the literature. This cross-sectional study included 60 patients with CD, aged 18–60 years. Dietary intake was assessed using a validated food frequency questionnaire to measure food consumption patterns by principal component analysis (PCA). Multiple regression analysis was performed to investigate the association between dietary patterns and clinical and demographic variables. Three dietary patterns were identified: “Traditional + FODMAP” was associated with symptoms, gender, previous surgeries, and duration of the disease. “Fitness style” was positively associated with physical activity and negatively associated with body mass index and smoking. “Snacks and processed foods” was positively associated with duration of the disease and negatively associated with age. According to the weekly food consumption analysis, patients with active disease consumed less coffee and tea. We found significant associations between the three dietary patterns and the variables, but not with the stage of the disease. Prospective studies are necessary to determine the effects of food consumption patterns on the clinical course of CD.
Heterogenetic parabiosis between healthy and dystrophic mice improve the histopathology in muscular dystrophy
Authors: Lu Aiping , Guo Ping , Wang Liang , Tseng Chieh , Huard Matthieu , Allen Chris , McCarrick-Walmsley Ruth , Whitney Kaitlyn E. , Huard Johnny 
Published: April 2020

AbstractDuchenne muscular dystrophy (DMD) is a progressive muscle disease, characterized by mutations in the X-linked dystrophin, that has several therapeutic options but no curative treatment. Transplantation of muscle progenitor cells for treatment of DMD has been widely investigated; however, its application is hindered by limited cell survival due to the harmful dystrophic microenvironment. An alternative approach to utilize progenitor cells and circulatory factors and to improve the dystrophic muscle pathology and microenvironment is through parabiotic pairing, where mice are surgically sutured to create a joint circulatory system. Parabiotic mice were generated by surgically joining wild type (WT) mice expressing green fluorescent protein (GFP) with mdx mice. These mice developed a common circulation (approximately 50% green cells in the blood of mdx mice) 2-weeks after parabiotic pairing. We observed significantly improved dystrophic muscle pathology, including decreased inflammation, necrotic fibers and fibrosis in heterogenetic parabionts. Importantly, the GFP + cells isolated from the mdx mice (paired with GFP mice) underwent myogenic differentiation in vitro and expressed markers of mesenchymal stem cells and macrophages, which may potentially be involved in the improvement of dystrophic muscle pathology. These observations suggest that changing the dystrophic microenvironment can be a new approach to treat DMD.
Method development and validation of ten pyrethroid insecticides in edible mushrooms by Modified QuEChERS and gas chromatography-tandem mass spectrometry
Authors: Tian Fajun , Qiao Chengkui , Luo Jing , Guo Linlin , Pang Tao , Pang Rongli , Li Jun , Wang Caixia , Wang Ruiping , Xie Hanzhong 
Published: April 2020

AbstractA method for simultaneous determination of ten pyrethroid insecticides residues in edible mushrooms was developed. The samples were pretreated by a quick, easy, cheap, effective, rugged (QuEChERS) method. The ten pyrethroid insecticides were extracted from six kinds of edible mushrooms using acetonitrile and subsequently cleaned up by octadecylsilane (C18) or primary secondary amine (PSA). Instrumental analysis was completed in 16 min using gas chromatography-tandem mass spectrometry (GC-MS/MS). The overall average recoveries in the six kinds of edible mushrooms at three levels (10, 100 and 1000 μg kg−1) ranged from 72.8% to 103.6%. The intraday and interday relative standard deviations (RSD) were lower than 13.0%. The quantification limits were below 5.57 μg kg−1 in different matrices. The results demonstrated that the method is convenient for the quick detection of pyrethroid insecticides in edible mushrooms.
A single nucleotide variant of human PARP1 determines response to PARP inhibitors
Authors: Cashman Rivki , Zilberberg Alona , Priel Avner , Philip Hagit , Varvak Alexander , Jacob Avi , Shoval Irit , Efroni Sol 
Published: April 2020

AbstractThe introduction of novel cancer drugs and innovative treatments brings great hope for cancer patients, but also an urgent need to match drugs to suitable patients, since certain drugs that benefit one patient may actually harm others. The newly developed poly-ADP ribose polymerase (PARP) inhibitors (PARPis) are a group of pharmacological enzyme inhibitors used clinically for multiple indications. Several forms of cancer tend to be PARP dependent, making PARP an attractive target for cancer therapy. Specifically, PARPis are commonly used in BRCA-associated breast cancers patients, since unrepaired single-strand breaks are converted into double-strand breaks and BRCA-associated tumors cannot repair them by homologous recombination so that PARPi leads to tumor cell death, by a mechanism called “Synthetic Lethality”. Unfortunately, not all patients respond to PARPi, and it is not currently possible to predict who will or will not respond. Here, we present a specific genomic marker, which reflects a single-nucleotide polymorphism of human PARP1 and correlates in vitro with response to PARPi, throughout all indications. In addition, we report that this SNP is associated with re-shaping mRNA, and mRNA levels, and influences the final protein structure to expose new binding sites while hiding others. The status of the SNP is therefore critical to patients’ care, as it relates responses to PARPi to the PARP1-SNP carried.
Simulating nephron ion transport function using activated wafer electrodeionization
Authors: Hestekin Christa N. , Hestekin Jamie A. , Paracha Sadia , Morrison Grace , Pakkaner Efecan , Moore John , Santos de Souza Leticia , Stephens Sam , Atchley Catey , Kurtz Ira 
Published: April 2020

AbstractCurrent approaches for treating patients with end stage renal disease include hemodialysis and peritoneal dialysis, both of which are diffusion-based treatments that require a dialysate solution. The native kidney has separate filtration (glomerulus) and transport (nephron) capabilities. Although artificial methods for simulating glomerular function using membrane ultrafiltration have been proposed, there are no known technologies for simulating the ion transport functions of the nephron. Here we have created a synthetic nephron using activated wafer electrodeionization (AWEDI). AWEDI incorporates mesh electrodes within an electrodeionization wafer, allowing ion selectivity and transport rate to be modulated independently. We demonstrate the capabilities of AWEDI with several physiologically relevant ions which mimic the fine control of ion transport by the kidney. Furthermore, by integrating our AWEDI technology with ultrafiltration, nanofiltration, and reverse osmosis modules, the possibility of incorporating AWEDI technology in an artificial kidney is demonstrated.
From animal models to patients: the role of placental microRNAs, miR-210, miR-126, and miR-148a/152 in preeclampsia
Authors: Frazier Sonya , McBride Martin W. , Mulvana Helen , Graham Delyth 
Published: April 2020

AbstractPlacental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.
A statistical study of the long-term evolution of coronal hole properties as observed by SDO
Authors: Heinemann S. G. , Jerčić V. , Temmer M. , Hofmeister S. J. , Dumbović M. , Vennerstrom S. , Verbanac G. , Veronig A. M. 
Published: April 2020

Context.Understanding the evolution of coronal holes is especially important when studying the high-speed solar wind streams that emanate from them. Slow- and high-speed stream interaction regions may deliver large amounts of energy into the Earth’s magnetosphere-ionosphere system, cause geomagnetic storms, and shape interplanetary space.Aims.By statistically investigating the long-term evolution of well-observed coronal holes we aim to reveal processes that drive the observed changes in the coronal hole parameters. By analyzing 16 long-living coronal holes observed by the Solar Dynamic Observatory, we focus on coronal, morphological, and underlying photospheric magnetic field characteristics, and investigate the evolution of the associated high-speed streams.Methods.We use the Collection of Analysis Tools for Coronal Holes to extract and analyze coronal holes using 193 Å EUV observations taken by the Atmospheric Imaging Assembly as well as line–of–sight magnetograms observed by the Helioseismic and Magnetic Imager. We derive changes in the coronal hole properties and look for correlations with coronal hole evolution. Further, we analyze the properties of the high–speed stream signatures near 1AU from OMNI data by manually extracting the peak bulk velocity of the solar wind plasma.Results.We find that the area evolution of coronal holes shows a general trend of growing to a maximum followed by a decay. We did not find any correlation between the area evolution and the evolution of the signed magnetic flux or signed magnetic flux density enclosed in the projected coronal hole area. From this we conclude that the magnetic flux within the extracted coronal hole boundaries is not the main cause for its area evolution. We derive coronal hole area change rates (growth and decay) of (14.2 ± 15.0)×108km2per day showing a reasonable anti-correlation (ccPearson = −0.48) to the solar activity, approximated by the sunspot number. The change rates of the signed mean magnetic flux density (27.3 ± 32.2 mG day−1) and the signed magnetic flux (30.3 ± 31.5 1018Mx day−1) were also found to be dependent on solar activity (ccPearson = 0.50 andccPearson = 0.69 respectively) rather than on the individual coronal hole evolutions. Further we find that the relation between coronal hole area and high-speed stream peak velocity is valid for each coronal hole over its evolution, but we see significant variations in the slopes of the regression lines.