bluuebunny/crossref_metadata_2025_split huggingface dataset:
Superresolution microscopy reveals photoreceptor-specific subciliary location and function of Cep290
Authors: Potter Valencia L. , Moye Abigail R. , Robichaux Michael A. , Wensel Theodore G. 
Published: October 2020

AbstractMutations in the cilium-associated protein CEP290 cause retinal degeneration as part of multi-organ syndromic ciliopathies or as retina-specific diseases. The precise location and the functional roles of CEP290 within cilia and, specifically, the connecting cilia (CC) of photoreceptors, remain unclear. We used superresolution fluorescence microscopy and electron microscopy (TEM) to localize CEP290 in the CC and in primary cilia of cultured cells with sub-diffraction resolution, and to determine effects of CEP290 deficiency. Radially, CEP290 co-localizes with the microtubule doublets and extends beyond them. Longitudinally, it is distributed throughout the length of the CC but is strictly confined to the very base of primary cilia in hRPE-1 cells. We found Y-shaped links, the ciliary sub-structures between microtubules and membrane, at the base of the transition zone in primary cilia of epithelial cells and throughout the length of the CC. Severe CEP290 deficiencies in mouse models did not prevent assembly of cilia or cause obvious mislocalization of ciliary components in early stages of degeneration. They did not lead to loss of the Y-shaped links but caused changes in their structures. These results point to photoreceptor-specific functions of CEP290 essential for CC maturation and stability following the earliest stages of ciliogenesis.
Genetic ancestry predicts male-female affiliation in a natural baboon hybrid zone
Authors: Fogel Arielle S. , McLean Emily M. , Gordon Jacob B. , Archie Elizabeth A. , Tung Jenny , Alberts Susan C. 
Published: October 2020

ABSTRACTOpposite-sex social relationships are important predictors of fitness in many animals, including several group-living mammals. Consequently, understanding sources of variance in the tendency to form opposite-sex relationships is important for understanding social evolution. Genetic contributions are of particular interest due to their importance in long-term evolutionary change, but little is known about genetic effects on male-female relationships in social mammals, especially outside of the mating context. Here, we investigate the effects of genetic ancestry on male-female affiliative behavior in a hybrid zone between the yellow baboon (Papio cynocephalus) and the anubis baboon (P. anubis), in a population in which male-female social bonds are known predictors of lifespan. We place our analysis within the context of other social and demographic predictors of affiliative behavior in baboons. Genetic ancestry was the most consistent predictor of opposite-sex affiliative behavior we observed, with the exception of strong effects of dominance rank. Our results show that increased anubis genetic ancestry is associated with subtly, but significantly higher rates of opposite-sex affiliative behavior, in both males and females. Additionally, pairs of anubis-like males and anubis-like females were the most likely to socially affiliate, resulting in moderate assortativity in grooming and proximity behavior as a function of genetic ancestry. Our findings indicate that opposite-sex affiliative behavior partially diverged during baboon evolution to differentiate yellow and anubis baboons, despite overall similarities in their social structures and mating systems. Further, they suggest that affiliative behavior may simultaneously promote and constrain baboon admixture, through additive and assortative effects of ancestry, respectively.HIGHLIGHTSOpposite-sex social relationships can have important fitness consequences.In hybrid baboons, genetic ancestry predicted male-female affiliative behavior.Both an individual’s genetic ancestry and that of its social partner mattered.Male-female affiliation was assortative with respect to genetic ancestry.Dominance rank and group demography also influenced male-female social affiliation.
High dose IFN-βactivates GAF to enhance expression of ISGF3 target genes in epithelial cells
Authors: Kishimoto Kensei , Wilder Catera , Buchanan Justin , Nguyen Minh , Okeke Chidera , Hoffmann Alexander , Cheng Quen J. 
Published: October 2020

AbstractInterferonβ(IFN-β) signaling activates the transcription factor complex ISGF3 to induce gene expression programs critical for antiviral defense and host immune responses. It has also been observed that IFN-βactivates a second transcription factor, γ-activated factor (GAF), but the significance of this coordinated activation is unclear. We report that in respiratory epithelial cells high doses of IFN-βindeed activate both ISGF3 and GAF, which bind to distinct genomic locations defined by their respective DNA sequence motifs. In contrast, low doses of IFN-βpreferentially activate ISGF3 but not GAF. Surprisingly, in epithelial cells GAF binding does not induce nearby gene expression even when strongly bound to the promoter. Yet expression of interferon stimulated genes is enhanced when GAF and ISGF3 are both active compared to ISGF3 alone. Our data suggest that GAF enhances ISGF3 target gene expression by co-localizing with ISGF3 at some promoters and facilitating chromosome looping between distal enhancers and other promoters. We propose that GAF may function as a dose-sensitive amplifier of ISG expression to enhance antiviral immunity and establish pro-inflammatory states in respiratory epithelial cells.One sentence summaryGAF is transcriptionally inactive in epithelial cells but enhances expression of ISGF3 target genes, thus functioning as a dose-sensitive amplifier of the IFN-βresponse.
Emergent collective organization of bone cells in complex curvature fields
Authors: Callens Sebastien J.P. , Fan Daniel , van Hengel Ingmar A.J. , Minneboo Michelle , Fratila-Apachitei Lidy E. , Zadpoor Amir A. 
Published: October 2020

AbstractIndividual cells and multicellular systems have been shown to respond to cell-scale curvatures in their environments, guiding migration, orientation, and tissue formation. However, it remains unclear how cells collectively explore and pattern complex landscapes with curvature gradients across the Euclidean and non-Euclidean spectra, partly owing to fabrication limitations and the lack of formal geometric considerations. Here, we show that micro-engineered substrates with controlled curvature variations induce the collective spatiotemporal organization of preosteoblasts. By leveraging mathematical surface design and a high-resolution free-form fabrication process, we exposed cells to a broad yet controlled, heterogeneous spectrum of curvature fields. We quantified curvature-induced spatial patterning at different time points and found that cells generally prefer regions with at least one negative principal curvature. We also show that multicellular cooperation enables cells to venture into unfavourably-curved territories, bridging large portions of the substrates, and collectively aligning their stress fibres. We demonstrate that this behaviour is partly regulated by cellular contractility and extracellular matrix development, underscoring the mechanical nature of curvature guidance. Our findings offer unifying perspectives on cell-geometry interactions that could be harnessed in the design of micro-engineered biomaterials, for example, for tissue engineering applications.
Automated Detection and Diameter Estimation for Mouse Mesenteric Artery using Semantic Segmentation
Authors: Higaki Akinori , Mahmoud Ahmad U. M. , Paradis Pierre , Schiffrin Ernesto L. 
Published: October 2020

AbstractBackgroundPressurized myography is useful for the assessment of small artery structure and function, and widely used in the field of cardiovascular research. However, this procedure requires technical expertise for the sample preparation and effort to choose an appropriate size of artery. In this study we sought to develop an automatic artery-vein differentiation and size measurement system utilizing the U-Net-based machine learning algorithms.Methods and ResultsWe used 654 independent mesenteric artery images from 59 mice for the model training and validation. Our segmentation model yielded 0.744 ±0.031 in IoU and 0.881 ±0.016 in Dice coefficient with 5-fold cross validation. The vessel size and the lumen size calculated from the predicted vessel contours demonstrated a strong linear correlation with the manually determined vessel sizes (R = 0.722 ±0.048, p<0.001 for vessel size and R = 0.908 ±0.027, p<0.001 for lumen size). Lastly, we assessed the relation between the vessel size before and after dissection using pressurized myography system. We observed a strong positive correlation between the wall/lumen ratio before dissection and the lumen expansion ratio (R2= 0.671, p<0.01). Using multivariate binary logistic regression, two models estimating whether the vessel met the size criteria (lumen size of 160 to 240 μm) were generated with area under the ROC curve of 0.761 for the upper limit and 0.747 for the lower limit.ConclusionOur novel image analysis method with U-Net could streamline the experimental approach and may facilitate cardiovascular research.
Neuromuscular control of gait stability in older adults is adapted to environmental demands but not improved after standing balance training
Authors: Alizadehsaravi Leila , Bruijn Sjoerd M. , Muijres Wouter , Koster Ruud A.J. , van Dieën Jaap H. 
Published: October 2020

AbstractBalance training aims to improve balance and transfer acquired skills to real-life tasks and conditions. How older adults adapt gait control to different conditions, and whether these adaptations are altered by balance training remains unclear. We investigated adaptations in neuromuscular control of gait in twenty-two older adults (72.6 ± 4.2 years) between normal (NW) and narrow-base walking (NBW), and the effects of a standing balance training program shown to enhance unipedal balance control in the same participants. At baseline, after one session and after 3-weeks of training, kinematics and EMG of NW and NBW on a treadmill were measured. Gait parameters and temporal activation profiles of five synergies extracted from 11 muscles were compared between time-points and gait conditions. No effects of balance training or interactions between training and walking condition on gait parameters or synergies were found. Trunk center of mass (CoM) displacement and velocity (vCoM), and the local divergence exponent (LDE), were lower in NBW compared to NW. For synergies associated with stance of the non-dominant leg and weight acceptance of the dominant leg, full width at half maximum (FWHM) of the activation profiles was smaller in NBW compared to NW. For the synergy associated with non-dominant heel strike, FWHM was greater in NBW compared to NW. The Center of Activation (CoA) of the activation profile associated with dominant leg stance occurred earlier in NBW compared to NW. CoAs of activation profile associated with non-dominant stance and non-dominant and dominant heel strikes were delayed in NBW compared to NW. The adaptations of synergies to NBW can be interpreted as related to a more cautious weight transfer to the new stance leg and enhanced control over CoM movement in the stance phase. However, control of mediolateral gait stability and these adaptations were not affected by balance training.
Inhibition of USP4 attenuates epithelial-mesenchymal transition of renal tubular epithelial cells by TβRI
Authors: Pu Jin-yun , Zhang Yu , Wang Li-xia , Wang Jie , Zhou Jian-hua 
Published: October 2020

AbstractThe process of epithelial-mesenchymal transition (EMT) is required for the progression of renal interstitial fibrosis (RIF). Ubiquitin-specific protease 4 (USP4) can facilitate development of transforming growth factor, beta 1 (TGF-β1) induced EMT in some cancer cells. However, the role of USP4 in EMT during RIF remains unknown. We aimed to explore the effect of USP4 on the EMT induced by TGF-β1 of renal tubular epithelial cells and involved mechanism in RIF. In vivo, on the 7th and 14th day after unilateral ureteral obstruction (UUO), the expression of USP4 protein in the obstructed kidneys was detected by immunohistochemistry and Western blot assay. In vitro, NRK-52E cells were stimulated with TGF-β1 10ng/ml. The protein expressions of USP4, E-cadherin and alpha smooth muscle actin (α-SMA) were detected at different time points by Western blot. After transfected with USP4 siRNA, the cells were cultured with TGF-β1 for additional 24 hours. The expressions of E-cadherin, α-SMA, and TGFβ receptor type I (TβRI) were detected by immunofluorescence. And the protein expressions of USP4, E-cadherin, α-SMA and TβRI were detected by Western blot assay. Compared with sham operation group, the expression of USP4 in UUO model group increased significantly with the prolongation of obstruction time. After NRK-52E was stimulated by TGF-β1, the expression of USP4 protein increased gradually. At 6h, 12h, and 24h, the difference between the experimental group and the control group was statistically significant. At the same time, E-cadherin decreased significantly, while α-SMA increased significantly. Compared with the TGF-β1 group, the cells in USP4 siRNA transfection group restored E-cadherin and weakened α-SMA expression. At the same time, protein expressions of USP4 and TβRI were also significantly decreased. These data imply that USP4 is a harmful molecule induced by TGF-β1, which plays an important role by upregulating the expression of TβRI and promoting EMT of renal tubular epithelial cells, thereby facilitating renal interstitial fibrosis.
Sirt1 overexpression attenuates high-fat diet induced aortic stiffening
Authors: Gogulamudi Venkateswara R. , Machin Daniel R. , Henson Grant , Donato Anthony J. , Lesniewski Lisa A. 
Published: October 2020

AbstractIncreased arterial stiffness is a cardiovascular disease risk factor in the setting of advancing age and high-fat (HF) diet induced obesity. Increases in large artery stiffness, as measured by pulse wave velocity (PWV), occur within 8 weeks of HF feeding in mice. Sirtuin-1 (Sirt1), a NAD-dependent deacetylase, regulates cellular metabolic activity and activation of this protein has been associated with vasoprotection in aged mice. The aim of the present study was to elucidate the effect of global Sirt1 overexpression (Sirttg) on HF diet-induced arterial stiffening. Sirt1 overexpression did not influence PWV in normal chow (NC) fed mice (Sirttg: 263 ± 6 vs WT: 274 ± 7, p=0.28). However, PWV was higher in wild-type (WT) mice (376 ± 22, p<0.04), but not Sirttg(304 ± 2 cm/s, p=0.07), after 12 weeks of HF diet. Despite no effect of Sirt1 overexpression on aortic collagen content in NC (p=0.71), aortic elastin content was higher in Sirttgmice compared with WT mice fed NC diet (P<0.05). Surprisingly, despite increased arterial stiffness, collagen content was lower (p<0.02) and elastin content was unchanged (p=0.05) in the aortas of WT mice after HF. Neither collagen (p=0.18) nor elastin content (p=0.56) were impacted by HF diet in the Sirttgmice. Likewise, there was no difference in wall thickness in NC (Sirttg: 40.7 ± 2 vs WT: 41.6 ± 2, p= 0.78). However, wall thickness was higher in mice WT mice fed a HF diet (51.7 ± 2, p<0.01) and there was no difference in Sirttgmice after HF diet (p=0.66). Similarly, there was no difference in wall-to-lumen ratio in mice fed NC diet (Sirttg: 0.08 vs WT: 0.08, p=0.48) was higher in HF diet fed WT mice (p<0.01), though, HF diet was associated with a higher wall-to-lumen ratio in WT (0.11, p<0.01), but not different in Sirttgmice fed HF diet (0.08, p=0.59). These findings demonstrate a vasoprotective effect of Sirt1 overexpression that limits increases in arterial stiffness and protects against alterations in vessel morphology in response to HF feeding. As such, activation of Sirt1 may be a novel therapeutic target to prevent elevated CVD risk associated with HF-induced aortic stiffening.
Ethacridine inhibits SARS-CoV-2 by inactivating viral particles in cellular models
Authors: Li Xiaoquan , Lidsky Peter , Xiao Yinghong , Wu Chien-Ting , Garcia-Knight Miguel , Yang Junjiao , Nakayama Tsuguhisa , Nayak Jayakar V. , Jackson Peter K. , Andino Raul , Shu Xiaokun 
Published: October 2020

AbstractSARS-CoV-2 is the coronavirus that causes the respiratory disease COVID-19, which is now the third-leading cause of death in the United States. The FDA has recently approved remdesivir, an inhibitor of SARS-CoV-2 replication, to treat COVID-19, though recent data from the WHO shows little to no benefit with use of this anti-viral agent. Here we report the discovery of ethacridine, a safe antiseptic use in humans, as a potent drug for use against SARS-CoV-2 (EC50~ 0.08μM). Ethacridine was identified via high-throughput screening of an FDA-approved drug library in living cells using a fluorescent assay. Interestingly, the main mode of action of ethacridine is through inactivation of viral particles, preventing their binding to the host cells. Indeed, ethacridine is effective in various cell types, including primary human nasal epithelial cells. Taken together, these data identify a promising, potent, and new use of the old drug possessing a distinct mode of action for inhibiting SARS-CoV-2.
Structural insights into the cooperative interaction of the intrinsically disordered co-activator TIF2 with retinoic acid receptor heterodimer (RXR/RAR)
Authors: Senicourt Lucile , Maire Albane le , Allemand Frédéric , Carvalho JoÃo E. , Guee Laura , Germain Pierre , Schubert Michael , Bernadó Pau , Bourguet William , Sibille Nathalie 
Published: October 2020

ABSTRACTRetinoic acid receptors (RARs) and retinoid X receptors (RXRs) form heterodimers that activate target gene transcription by recruiting co-activator complexes in response to ligand binding. The nuclear receptor (NR) co-activator TIF2 mediates this recruitment by interacting with the ligand-binding domain (LBD) of NRs trough the nuclear receptor interaction domain (TIF2NRID) containing three highly conserved α-helical LxxLL motifs (NR-boxes). The precise binding mode of this domain to RXR/RAR is not clear due to the disordered nature of TIF2. Here we present the structural characterization of TIF2NRIDby integrating several experimental (NMR, SAXS, CD, SEC-MALS) and computational data. Collectively, the data are in agreement with a largely disordered protein with partially structured regions, including the NR-boxes and their flanking regions, which are evolutionary conserved. NMR and X-ray crystallographic data on TIF2NRIDin complex with RXR/RAR reveal a cooperative binding of the three NR-boxes as well as an active role of their flanking regions in the interaction.
Innervation and Neuronal Control of the Mammalian Sinoatrial Node: A Comprehensive Atlas
Authors: Hanna Peter , Dacey Michael J. , Brennan Jaclyn , Moss Alison , Robbins Shaina , Achanta Sirisha , Biscola Natalia P. , Swid Mohammed A. , Rajendran Pradeep S. , Mori Shumpei , Hadaya Joseph E. , Smith Elizabeth H. , Peirce Stanley G. , Chen Jin , Havton Leif A. , Cheng Zixi (Jack) , Vadigepalli Rajanikanth , Schwaber James , Lux Robert L. , Efimov Igor , Tompkins John D. , Hoover Donald B. , Ardell Jeffrey L. , Shivkumar Kalyanam 
Published: October 2020

AbstractCardiac function is under exquisite intrinsic cardiac neural control. Neuroablative techniques to modulate control of cardiac function are currently being studied in patients, albeit with variable and sometimes deleterious results. Recognizing the major gaps in our understanding of cardiac neural control, we sought to evaluate neural regulation of impulse initiation in the sinoatrial node as an initial discovery step. Here, we report an in-depth, multi-scale structural and functional characterization of the innervation of the sinoatrial node (SAN) by the right atrial ganglionated plexus (RAGP) in porcine and human hearts. Combining intersectional strategies including tissue clearing, immunohistochemical and ultrastructural techniques, we have delineated a comprehensive neuroanatomic atlas of the RAGP-SAN complex. The RAGP shows significant phenotypic diversity of neurons while maintaining predominant cholinergic innervation. Cellular and tissue-level electrophysiologic mapping and ablation studies demonstrate interconnected ganglia with synaptic convergence within the RAGP to modulate SAN automaticity, atrioventricular (AV) conduction and left ventricular (LV) contractility. For the first time, we demonstrate that intrinsic cardiac neurons influence the pacemaking site in the heart. This provides an experimental demonstration of a discrete neuronal population controlling a specific geographic region of the heart (SAN) that can serve as a framework for further exploration of other parts of the intrinsic cardiac nervous system (ICNS) in mammalian hearts and for developing targeted therapies.
Pronounced proliferation of non-beta cells in response to beta-cell mitogens in isolated human islets of Langerhans
Authors: Maachi Hasna , Ghislain Julien , Tremblay Caroline , Poitout Vincent 
Published: October 2020

ABSTRACTThe potential to treat diabetes by increasing beta-cell mass is driving a major effort to identify beta-cell mitogens. Demonstration of mitogen activity in human beta cells is frequently performed in ex vivo assays. However, reported disparities in the efficacy of beta-cell mitogens led us to investigate the sources of this variability. We studied 35 male (23) and female (12) human islet batches covering a range of donor ages and BMI. Islets were kept intact or dispersed into single cells and cultured in the presence of harmine, glucose, or heparin-binding epidermal growth factor-like growth factor (HB-EGF), and subsequently analyzed by immunohistochemistry or flow cytometry. Proliferating cells were identified by double labelling with EdU and Ki67 and glucagon, c-peptide or Nkx6.1, and cytokeratin-19 to respectively label alpha, beta, and ductal cells. Harmine and HB-EGF stimulated human beta-cell proliferation, but the effect of glucose was dependent on the assay and the donor. Harmine potently stimulated alpha-cell proliferation and both harmine and HB-EGF increased proliferation of insulin- and glucagon-negative cells, including cytokeratin 19-positive cells. Given the abundance of non-beta cells in human islet preparations, our results suggest that assessment of beta-cell mitogens requires complementary approaches and rigorous identification of cell identity using multiple markers.
Whole-genome analysis of Nigerian patients with breast cancer reveals ethnic-driven somatic evolution and distinct genomic subtypes
Authors: Ansari-Pour Naser , Zheng Yonglan , Pitt Jason J. , Dentro Stefan , Yoshimatsu Toshio F. , Sanni Ayodele , Ajani Mustapha , Woodard Anna , Rajagopal Padma Sheila , Fitzgerald Dominic , Gruber Andreas J. , Odetunde Abayomi , Popoola Abiodun , Falusi Adeyinka G. , Babalola Chinedum Peace , Ogundiran Temidayo , Obafunwa John , Ojengbede Oladosu , Ibrahim Nasiru , Barretina Jordi , Van Loo Peter , Chen Mengjie , White Kevin P. , Huo Dezheng , Wedge David C. , Olopade Olufunmilayo I. 
Published: October 2020

AbstractBlack women of African ancestry experience more aggressive breast cancer with higher mortality rates than White women of European ancestry. Although inter-ethnic germline variation is known, differential somatic evolution has not been investigated in detail. Analysis of deep whole genomes of 97 breast tumors, with RNA-seq in a subset, from indigenous African patients in Nigeria in comparison to The Cancer Genome Atlas (n=76) revealed a higher rate of genomic instability and increased intra-tumoral heterogeneity as well as a unique genomic subtype defined by early clonalGATA3mutations and a 10.5-year younger age at diagnosis. We also found evidence for non-coding mutations in two novel drivers (ZNF217andSYPL1) and a novel INDEL signature strongly associated with African ancestry proportion. This comprehensive analysis of an understudied population underscores the need to incorporate diversity of genomes as a key parameter in fundamental research with potential to tailor clinical intervention and promote equity in precision oncology care.