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  • Article
    Travouillon KJ, Simões BF, Miguez RP, Brace S, Brewer P, Stemmer D, Price GJ, Cramb J, Louys J.
    Zootaxa. 2019 Mar 13;4566(1):zootaxa.4566.1.1.
    The Pig-footed Bandicoot, Chaeropus ecaudatus, an extinct arid-adapted bandicoot, was named in 1838 based on a specimen without a tail from the Murray River in New South Wales. Two additional species were later named, C. castanotis and C. occidentalis, which have since been synonymised with C. ecaudatus. Taxonomic research on the genus is rather difficult because of the limited material available for study. Aside from the types of C. castanotis and C. occidentalis housed at the Natural History Museum in London, and the type of C. ecaudatus at the Australian Museum in Sydney, there are fewer than 30 other modern specimens in other collections scattered around the world. Examining skeletal and dental characters for several specimens, and using a combination of traditional morphology, morphometrics, palaeontology and molecular phylogenetics, we have identified two distinct species, C. ecaudatus and C. yirratji sp. nov., with C. ecaudatus having two distinct subspecies, C. e. ecaudatus and C. e. occidentalis. We use palaeontological data to reconstruct the pre-European distribution of the two species, and review the ecological information known about these extinct taxa.
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  • Article
    Lu N, Guo H, Wang L, Wu X, Zeng XC.
    Nanoscale. 2014 May 07;6(9):4566-71.
    We perform a comprehensive first-principles study of the electronic properties of van der Waals (vdW) trilayers via intercalating a two-dimensional (2D) monolayer (ML = BN, MoSe2, WS2, or WSe2) between a MoS2 bilayer to form various MoS2/ML/MoS2 sandwich trilayers. We find that the BN monolayer is the most effective sheet to decouple the interlayer vdW coupling of the MoS2 bilayer, and the resulting sandwich trilayer can recover the electronic structures of the MoS2 monolayer, particularly the direct-gap character. Further study of the MoS2/BN superlattices confirms the effectiveness of the BN monolayer for the decoupling of the MoS2-MoS2 interaction. In addition, the intercalation of a transition-metal dichalcogenide (TMDC) MoSe2 or WSe2 sheet makes the sandwich trilayer undergo an indirect-gap to direct-gap transition due to the newly formed heterogeneous S/Se interfaces. In contrast, the MoS2/WS2/MoS2 sandwich trilayer still retains the indirect-gap character of the MoS2 bilayer due to the lack of the heterogeneous S/Se interfaces. Moreover, the 3D superlattice of the MoS2/TMDC heterostructures also exhibits similar electronic band characters to the MoS2/TMDC/MoS2 trilayer heterostructures, albeit a slight decrease of the bandgap compared to the trilayers. Compared to the bulk MoS2, the 3D MoS2/TMDC superlattice can give rise to new and distinctive properties. Our study offers not only new insights into electronic properties of the vdW multilayer heterostructures but also guidance in designing new heterostructures to modify electronic structures of 2D TMDC crystals.
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  • Article
    Zhao Y, Chen Y, Jin M, Wang J.
    Theranostics. 2021;11(9):4549-4566.
    Epigenetic regulation involves a range of sophisticated processes which contribute to heritable alterations in gene expression without altering DNA sequence. Regulatory events predominantly include DNA methylation, chromatin remodeling, histone modifications, non-coding RNAs (ncRNAs), and RNA modification. As the most prevalent RNA modification in eukaryotic cells, N6-methyladenosine (m6A) RNA methylation actively participates in the modulation of RNA metabolism. Notably, accumulating evidence has revealed complicated interrelations occurring between m6A and other well-known epigenetic modifications. Their crosstalk conspicuously triggers epigenetic remodeling, further yielding profound impacts on a variety of physiological and pathological processes, especially tumorigenesis. Herein, we provide an up-to-date review of this emerging hot area of biological research, summarizing the interplay between m6A RNA methylation and other epigenetic regulators, and highlighting their underlying functions in epigenetic reprogramming.
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  • Article
    Wells SM, Widen JC, Harki DA, Brummond KM.
    Org Lett. 2016 09 16;18(18):4566-9.
    The Nicholas reaction has been applied to the installation of alkyne ligation handles. Acid-promoted propargylation of hydroxyl, sulfhydryl, amino, and carboxyl groups using dicobalt hexacarbonyl-stabilized propargylium ions is reported. This method is useful for introduction of propargyl groups into base-sensitive molecules, thereby expanding the toolbox of methods for the incorporation of alkynes for bio-orthogonal reactions. High-value molecules are used as the limiting reagent, and various propargylium ion precursors are compared.
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  • Article
    Feng Y, Xu W, Zhang W, Wang W, Liu T, Zhou X.
    Theranostics. 2019;9(15):4558-4566.
    Background: We generated a rat model of diabetic cardiomyopathy (DCM) and reported significant upregulation of the long non-coding RNA DCRF. This study was designed to determine the molecular mechanisms of DCRF in the development of DCM. Methods: Real-time PCR and RNA fluorescent in situ hybridization were conducted to detect the expression pattern of DCRF in cardiomyocytes. Histological and echocardiographic analyses were used to assess the effect of DCRF knockdown on cardiac structure and function in diabetic rats. mRFP-GFP-LC3 fluorescence microscopy, transmission electron microscopy, and Western blotting were carried out to determine cardiomyocyte autophagy. RNA immunoprecipitation and luciferase reporter assays were performed to elucidate the regulatory role of DCRF/miR-551b-5p/PCDH17 pathway in cardiomyocyte autophagy. Results: Our findings showed that DCRF knockdown reduced cardiomyocyte autophagy, attenuated myocardial fibrosis, and improved cardiac function in diabetic rats. High glucose increased DCRF expression and induced autophagy in cardiomyocytes. RNA immunoprecipitation and luciferase reporter assays indicated that DCRF was targeted by miR-551b-5p in an AGO2-dependent manner and PCDH17 was the direct target of miR-551b-5p. Forced expression of DCRF was found to attenuate the inhibitory effect of miR-551b-5p on PCDH17. Furthermore, DCRF knockdown decreased PCDH17 expression and suppressed autophagy in cardiomyocytes treated with high glucose. Conclusion: Our study suggests that DCRF can act as a competing endogenous RNA to increase PCDH17 expression by sponging miR-551b-5p, thus contributing to increased cardiomyocyte autophagy in DCM.
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  • Article
    Salzano G, Costa DF, Torchilin VP.
    Curr Pharm Des. 2015;21(31):4566-73.
    Since its discovery in the late 1990, small interfering RNA (siRNA) have quickly crept into the biopharmaceutical research as a new and powerful tool for the treatment of different human diseases based on altered gene-expression. Despite promising data from many pre-clinical studies, concrete hurdles still need to be overcome to bring therapeutic siRNAs in clinic. The design of stimuli-sensitive nanopreparations for gene therapy is a lively area of the current research. Compared to conventional systems for siRNA delivery, this type of platform can respond to local stimuli that are characteristics of the pathological area of interest, allowing the release of nucleic acids at the desired site. Acidic pH, de-regulated levels of enzymes, altered redox potential and magnetic field are examples of stimuli exploit to design stimuli-sensitive nanoparticles. In this review, we discuss on recent stimulisensitive strategies for siRNA delivery and we highlight on the potential of combining multiple stimuli-sensitive strategies in the same nano-platform for a better therapeutic outcome.
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  • Article
    Gaiser P, Binz J, Gompf B, Berrier A, Dressel M.
    Nanoscale. 2015 Mar 14;7(10):4566-71.
    Tunable metal/dielectric composites are promising candidates for a large number of potential applications in electronics, sensor technologies and optical devices. Here we systematically investigate the dielectric properties of Ag-nanoparticles embedded in the highly flexible elastomer poly-dimethylsiloxane (PDMS). As tuning parameter we use uniaxial and biaxial strain applied to the composite. We demonstrate that both static variations of the filling factor and applied strain lead to the same behavior, i.e., the filling factor of the composite can be tuned by application of strain. In this way the effective static permittivity εeff of the composite can be varied over a very large range. Once the Poisson's ratio of the composite is known, the strain dependent dielectric constant can be accurately described by effective medium theory without any additional free fit parameter up to metal filling factors close to the percolation threshold. It is demonstrated that, starting above the percolation threshold in the metallic phase, applying strain provides the possibility to cross the percolation threshold into the insulating region. The change of regime from conductive phase down to insulating follows the description given by percolation theory and can be actively controlled.
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  • Article
    Hu K, Yin F, Yu M, Sun C, Li J, Liang Y, Li W, Xie M, Lao Y, Liang W, Li ZG.
    Theranostics. 2017;7(18):4566-4576.
    Inhibition of the interaction between p53 and MDM2/MDMX has attracted significant attention in anticancer therapy development. We designed a series of in-tether chiral center-induced helical stabilized peptides, among which MeR/PhR effectively reactivated p53. The activation of p53 inhibits cell proliferation and induces apoptosis in both the MCF-7 normal tumor cell line and the PA-1 pluripotent cancer cell line with only minimal cellular toxicity towards normal cells or cancer cell lines with p53 mutations. The in vivo bioactivity study of the peptide in the ovarian teratocarcinoma (PA-1) xenograft model showed a tumor growth rate inhibition of 70% with a dosage of 10 mg/kg (one injection every other day). This is the first application of a stabilized peptide modulator targeting stem-like cancer cell both in vitro and in vivo and provides references to cancer stem cell therapy.
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  • Article
    Saulle R, Semyonov L, La Torre G.
    Nutrients. 2013 Nov 18;5(11):4566-86.
    The growing impact of chronic degenerative pathologies (such as cardiovascular disease, type 2 diabetes and Alzheimer's disease) requires and pushes towards the development of new preventive strategies to reduce the incidence and prevalence of these diseases. Lifestyle changes, especially related to the Mediterranean diet, have the potential to modify disease outcomes and ultimately costs related to their management. The objective of the study was to perform a systematic review of the scientific literature, to gauge the economic performance and the cost-effectiveness of the adherence to the Mediterranean diet as a prevention strategy against degenerative pathologies. We investigated the monetary costs of adopting Mediterranean dietary patterns by determining cost differences between low and high adherence. Research was conducted using the PubMed and Scopus databases. Eight articles met the pre-determined inclusion criteria and were reviewed. Quality assessment and data extraction was performed. The adherence to the Mediterranean diet has been extensively reported to be associated with a favorable health outcome and a better quality of life. The implementation of a Mediterranean dietary pattern may lead to the prevention of degenerative pathologies and to an improvement in life expectancy, a net gain in health and a reduction in total lifetime costs.
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  • Article
    Vasanthakrishnan RB, de Las Heras A, Scortti M, Deshayes C, Colegrave N, Vázquez-Boland JA.
    Environ Microbiol. 2015 Nov;17(11):4566-79.
    Virulence traits are essential for pathogen fitness, but whether they affect microbial performance in the environment, where they are not needed, remains experimentally unconfirmed. We investigated this question with the facultative pathogen Listeria monocytogenes and its PrfA virulence regulon. PrfA-regulated genes are activated intracellularly (PrfA 'ON') but shut down outside the host (PrfA 'OFF'). Using a mutant PrfA regulator locked ON (PrfA*) and thus causing PrfA-controlled genes to be constitutively activated, we show that virulence gene expression significantly impairs the listerial growth rate (μ) and maximum growth (A) in rich medium. Deletion analysis of the PrfA regulon and complementation of a L. monocytogenes mutant lacking all PrfA-regulated genes with PrfA* indicated that the growth reduction was specifically due to the unneeded virulence determinants and not to pleiotropic regulatory effects of PrfA ON. No PrfA*-associated fitness disadvantage was observed in infected eukaryotic cells, where PrfA-regulated virulence gene expression is critical for survival. Microcosm experiments demonstrated that the constitutively virulent state strongly impaired L. monocytogenes performance in soil, the natural habitat of these bacteria. Our findings provide empirical proof that virulence carries a significant cost to the pathogen. They also experimentally substantiate the assumed, although not proven, key role of virulence gene regulation systems in suppressing the cost of bacterial virulence outside the host.
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  • Article
    Yang J, Zhang N, He Z, Xiong J, Meng W, Xue C, Ying L, Li M, Liu M, Ouyang T.
    J Cancer. 2024;15(14):4566-4576.
    Background: OTUB1, an essential deubiquitinating enzyme, is upregulated in various types of cancer. Previous studies have shown that OTUB1 may be an oncogene in glioblastoma multiforme (GBM), but its specific regulatory mechanism remains unclear. This study aimed to investigate the mechanism by which OTUB1 and the JAK2/STAT1 signaling pathway co-regulate the growth of GBM. Methods: Using bioinformatics, GBM tissues, and cells, we evaluated the expression and clinical significance of OTUB1 in GBM. Subsequently, we explored the regulatory mechanisms of OTUB1 on malignant behaviors in GBM in vitro and in vivo. In addition, we added the JAK2 inhibitor AZD1480 to explore the regulation of OTUB1 for JAK2/STAT1 pathway in GBM. Results: We found that OTUB1 expression was upregulated in GBM. Silencing OTUB1 promotes apoptosis and cell cycle arrest at G1 phase, inhibiting cell proliferation. Moreover, OTUB1 knockdown effectively inhibited the invasion and migration of GBM cells, and the opposite phenomenon occurred with overexpression. In vivo experiments revealed that OTUB1 knockdown inhibited tumor growth, further emphasizing its crucial role in GBM progression. Mechanistically, we found that OTUB1 was negatively correlated with the JAK2/STAT1 pathway in GBM. The addition of the JAK2 inhibitor AZD1480 significantly reversed the effects of silencing OTUB1 on GBM. Conclusion: Our study reveals a novel mechanism by which OTUB1 inhibits the JAK2/STAT1 signaling pathway. This contributes to a better understanding of OTUB1's role in GBM and provides a potential avenue for targeted therapeutic intervention.
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  • Article
    Feng J, Zhang Y, Ren X, Li D, Fu H, Liu C, Zhou W, Liu Q, Liu Q, Wu M.
    Oncogene. 2020 06;39(23):4551-4566.
    Temozolomide (TMZ) insensitivity and resistance are major causes of treatment failure and poor prognosis for GBM patients. Here, we identify LRRC4 as a novel autophagy inhibitor that restores the sensitivity of GBMs to TMZ. LRRC4 was associated with the DEPTOR/mTOR complex, and this interaction resulted in autophagy inhibition. Further investigation demonstrated that the PDZ binding domain of LRRC4 binds to the PDZ domain of DEPTOR. This binding decreases the half-life of DEPTOR via ubiquitination, thus inhibiting GBM cell autophagy and increasing the TMZ treatment response of GBM. Combined LRRC4 expression and TMZ treatment prolonged the survival of mice with tumour xenografts. Furthermore, the levels of LRRC4, DEPTOR and autophagy are clinically relevant for GBM, indicating that LRRC4 is likely to have significant potential as a therapeutic marker and target for TMZ treatment in glioma patients.
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  • Article
    Sequeira AMM, Mellin C, Lozano-Montes HM, Meeuwig JJ, Vanderklift MA, Haywood MDE, Babcock RC, Caley MJ.
    PeerJ. 2018;6:e4566.
    Reliable abundance estimates for species are fundamental in ecology, fisheries, and conservation. Consequently, predictive models able to provide reliable estimates for un- or poorly-surveyed locations would prove a valuable tool for management. Based on commonly used environmental and physical predictors, we developed predictive models of total fish abundance and of abundance by fish family for ten representative taxonomic families for the Great Barrier Reef (GBR) using multiple temporal scenarios. We then tested if models developed for the GBR (reference system) could predict fish abundances at Ningaloo Reef (NR; target system), i.e., if these GBR models could be successfully transferred to NR. Models of abundance by fish family resulted in improved performance (e.g., 44.1% <R2 < 50.6% for Acanthuridae) compared to total fish abundance (9% <R2 < 18.6%). However, in contrast with previous transferability obtained for similar models for fish species richness from the GBR to NR, transferability for these fish abundance models was poor. When compared with observations of fish abundance collected in NR, our transferability results had low validation scores (R2 < 6%, p > 0.05). High spatio-temporal variability of patterns in fish abundance at the family and population levels in both reef systems likely affected the transferability of these models. Inclusion of additional predictors with potential direct effects on abundance, such as local fishing effort or topographic complexity, may improve transferability of fish abundance models. However, observations of these local-scale predictors are often not available, and might thereby hinder studies on model transferability and its usefulness for conservation planning and management.
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  • Article
    Hutton LA, O'Neil GD, Read TL, Ayres ZJ, Newton ME, Macpherson JV.
    Anal Chem. 2014 May 06;86(9):4566-72.
    The development of a novel analytical technique, electrochemical X-ray fluorescence (EC-XRF), is described and applied to the quantitative detection of heavy metals in solution, achieving sub-ppb limits of detection (LOD). In EC-XRF, electrochemical preconcentration of a species of interest onto the target electrode is achieved here by cathodic electrodeposition. Unambiguous elemental identification and quantification of metal concentration is then made using XRF. This simple electrochemical preconcentration step improves the LOD of energy dispersive XRF by over 4 orders of magnitude (for similar sample preparation time scales). Large area free-standing boron doped diamond grown using microwave plasma chemical vapor deposition techniques is found to be ideal as the electrode material for both electrodeposition and XRF due to its wide solvent window, transparency to the XRF beam, and ability to be produced in mechanically robust freestanding thin film form. During electrodeposition it is possible to vary both the deposition potential (Edep) and deposition time (tdep). For the metals Cu(2+) and Pb(2+) the highest detection sensitivities were found for Edep = -1.75 V and tdep (=) 4000 s with LODs of 0.05 and 0.04 ppb achieved, respectively. In mixed Cu(2+)/Pb(2+) solutions, EC-XRF shows that Cu(2+) deposition is unimpeded by Pb(2+), across a broad concentration range, but this is only true for Pb(2+) when both metals are present at low concentrations (10 nM), boding well for trace level measurements. In a dual mixed metal solution, EC-XRF can also be employed to either selectively deposit the metal which has the most positive formal reduction potential, E(0), or exhaustively deplete it from solution, enabling uninhibited detection of the metal with the more negative E(0).
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  • Article
    Bouzon Nagem Assad D, Gomes Ferreira da Costa P, Spiegel T, Cara J, Ortega-Mier M, Monteiro Scaff A.
    Sci Rep. 2024 02 25;14(1):4566.
    The World Health Organization has highlighted that cancer was the second-highest cause of death in 2019. This research aims to present the current forecasting techniques found in the literature, applied to predict time-series cancer incidence and then, compare these results with the current methodology adopted by the Instituto Nacional do Câncer (INCA) in Brazil. A set of univariate time-series approaches is proposed to aid decision-makers in monitoring and organizing cancer prevention and control actions. Additionally, this can guide oncological research towards more accurate estimates that align with the expected demand. Forecasting techniques were applied to real data from seven types of cancer in a Brazilian district. Each method was evaluated by comparing its fit with real data using the root mean square error, and we also assessed the quality of noise to identify biased models. Notably, three methods proposed in this research have never been applied to cancer prediction before. The data were collected from the INCA website, and the forecast methods were implemented using the R language. Conducting a literature review, it was possible to draw comparisons previous works worldwide to illustrate that cancer prediction is often focused on breast and lung cancers, typically utilizing a limited number of time-series models to find the best fit for each case. Additionally, in comparison to the current method applied in Brazil, it has been shown that employing more generalized forecast techniques can provide more reliable predictions. By evaluating the noise in the current method, this research shown that the existing prediction model is biased toward two of the studied cancers Comparing error results between the mentioned approaches and the current technique, it has been shown that the current method applied by INCA underperforms in six out of seven types of cancer tested. Moreover, this research identified that the current method can produce a biased prediction for two of the seven cancers evaluated. Therefore, it is suggested that the methods evaluated in this work should be integrated into the INCA cancer forecast methodology to provide reliable predictions for Brazilian healthcare professionals, decision-makers, and oncological researchers.
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  • Article
    Tomson SN, Schreiner MJ, Narayan M, Rosser T, Enrique N, Silva AJ, Allen GI, Bookheimer SY, Bearden CE.
    Hum Brain Mapp. 2015 Nov;36(11):4566-81.
    Neurofibromatosis type I (NF1) is a genetic disorder caused by mutations in the neurofibromin 1 gene at locus 17q11.2. Individuals with NF1 have an increased incidence of learning disabilities, attention deficits, and autism spectrum disorders. As a single-gene disorder, NF1 represents a valuable model for understanding gene-brain-behavior relationships. While mouse models have elucidated molecular and cellular mechanisms underlying learning deficits associated with this mutation, little is known about functional brain architecture in human subjects with NF1. To address this question, we used resting state functional connectivity magnetic resonance imaging (rs-fcMRI) to elucidate the intrinsic network structure of 30 NF1 participants compared with 30 healthy demographically matched controls during an eyes-open rs-fcMRI scan. Novel statistical methods were employed to quantify differences in local connectivity (edge strength) and modularity structure, in combination with traditional global graph theory applications. Our findings suggest that individuals with NF1 have reduced anterior-posterior connectivity, weaker bilateral edges, and altered modularity clustering relative to healthy controls. Further, edge strength and modular clustering indices were correlated with IQ and internalizing symptoms. These findings suggest that Ras signaling disruption may lead to abnormal functional brain connectivity; further investigation into the functional consequences of these alterations in both humans and in animal models is warranted.
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  • Article
    Patterson BD, Gao Y, Seeger T, Kliewer CJ.
    Opt Lett. 2013 Nov 15;38(22):4566-9.
    We introduce a multiplex technique for the single-laser-shot determination of S-branch Raman linewidths with high accuracy and precision by implementing hybrid femtosecond (fs)/picosecond (ps) rotational coherent anti-Stokes Raman spectroscopy (CARS) with multiple spatially and temporally separated probe beams derived from a single laser pulse. The probe beams scatter from the rotational coherence driven by the fs pump and Stokes pulses at four different probe pulse delay times spanning 360 ps, thereby mapping collisional coherence dephasing in time for the populated rotational levels. The probe beams scatter at different folded BOXCARS angles, yielding spatially separated CARS signals which are collected simultaneously on the charge coupled device camera. The technique yields a single-shot standard deviation (1σ) of less than 3.5% in the determination of Raman linewidths and the average linewidth values obtained for N(2) are within 1% of those previously reported. The presented technique opens the possibility for correcting CARS spectra for time-varying collisional environments in operando.
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  • Article
    Guo M, Morley MP, Jiang C, Wu Y, Li G, Du Y, Zhao S, Wagner A, Cakar AC, Kouril M, Jin K, ... Show More Gaddis N, Kitzmiller JA, Stewart K, Basil MC, Lin SM, Ying Y, Babu A, Wikenheiser-Brokamp KA, Mun KS, Naren AP, Clair G, Adkins JN, Pryhuber GS, Misra RS, Aronow BJ, Tickle TL, Salomonis N, Sun X, Morrisey EE, Whitsett JA, NHLBI LungMAP Consortium, Xu Y.
    Nat Commun. 2023 07 29;14(1):4566.
    Accurate cell type identification is a key and rate-limiting step in single-cell data analysis. Single-cell references with comprehensive cell types, reproducible and functionally validated cell identities, and common nomenclatures are much needed by the research community for automated cell type annotation, data integration, and data sharing. Here, we develop a computational pipeline utilizing the LungMAP CellCards as a dictionary to consolidate single-cell transcriptomic datasets of 104 human lungs and 17 mouse lung samples to construct LungMAP single-cell reference (CellRef) for both normal human and mouse lungs. CellRefs define 48 human and 40 mouse lung cell types catalogued from diverse anatomic locations and developmental time points. We demonstrate the accuracy and stability of LungMAP CellRefs and their utility for automated cell type annotation of both normal and diseased lungs using multiple independent methods and testing data. We develop user-friendly web interfaces for easy access and maximal utilization of the LungMAP CellRefs.
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  • Article
    Rupp F, Haupt M, Klostermann H, Kim HS, Eichler M, Peetsch A, Scheideler L, Doering C, Oehr C, Wendel HP, Sinn S, Decker E, von Ohle C, Geis-Gerstorfer J.
    Acta Biomater. 2010 Dec;6(12):4566-77.
    Anatase is known to decompose organic material by photocatalysis and to enhance surface wettability once irradiated by ultraviolet (UV) light. In this study, pulse magnetron-sputtered anatase thin films were investigated for their suitability with respect to specific biomedical applications, namely superhydrophilic and biofilm degrading implant surfaces. UV-induced hydrophilicity was quantified by static and dynamic contact angle analysis. Photocatalytic protein decomposition was analyzed by quartz crystal microbalance with dissipation. The surfaces were characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. The radical formation on anatase, responsible for photocatalytic effects, was analyzed by electron spin resonance spectroscopy. Results have shown that the nanocrystalline anatase films, in contrast to reference titanium surfaces, were sensitive to UV irradiation and showed rapid switching towards superhydrophilicity. The observed decrease in carbon adsorbents and the increase in the fraction of surface hydroxyl groups upon UV irradiation might contribute to this hydrophilic behavior. UV irradiation of anatase pre-conditioned with albumin protein layers induces the photocatalytic decomposition of these model biofilms. The observed degradation is mainly caused by hydroxyl radicals. It is concluded that nanocrystalline anatase films offer different functions at implant interfaces, e.g. bedside hydrophilization of anatase-coated implants for improved osseointegration or the in situ decomposition of conditioning films forming the basal layer of biofilms in the oral cavity.
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  • Article
    Zhao MX, Bi HL, Jiang RH, Xu XW, Shi M.
    Org Lett. 2014 Sep 05;16(17):4566-9.
    An efficient diastereo- and enantioselective Mannich-type/cyclization cascade reaction of α-substituted isocyanoacetates and cyclic trifluoromethyl ketimines cooperatively catalyzed by cinchona alkaloid-derived multi-hydrogen-bonding donor squaramide and AgOAc has been investigated, affording the optically active trifluoromethyl-substituted tetrahydroimidazo[1,5-c]quinazoline derivatives in excellent yields (up to 99%) and good to excellent stereoselectivities (up to >15:1 dr, up to 98% ee) under mild conditions.
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