bluuebunny/crossref_metadata_2025_split huggingface dataset:
Navigating with grid and place cells in cluttered environments
Authors: Edvardsen Vegard , Bicanski Andrej , Burgess Neil 
Published: August 2019

AbstractHippocampal formation contains several classes of neurons thought to be involved in navigational processes, in particular place cells and grid cells. Place cells have been associated with a topological strategy for navigation, while grid cells have been suggested to support metric vector navigation. Grid cell‐based vector navigation can support novel shortcuts across unexplored territory by providing the direction toward the goal. However, this strategy is insufficient in natural environments cluttered with obstacles. Here, we show how navigation in complex environments can be supported by integrating a grid cell‐based vector navigation mechanism with local obstacle avoidance mediated by border cells and place cells whose interconnections form an experience‐dependent topological graph of the environment. When vector navigation and object avoidance fail (i.e., the agent gets stuck), place cell replay events set closer subgoals for vector navigation. We demonstrate that this combined navigation model can successfully traverse environments cluttered by obstacles and is particularly useful where the environment is underexplored. Finally, we show that the model enables the simulated agent to successfully navigate experimental maze environments from the animal literature on cognitive mapping. The proposed model is sufficiently flexible to support navigation in different environments, and may inform the design of experiments to relate different navigational abilities to place, grid, and border cell firing.
PD‐L1 expression is low in large B‐cell lymphoma with MYC or double‐hit translocation
Authors: Elbæk Mette Vestergaard , Pedersen Mette Ølgod , Breinholt Marie Fredslund , Reddy Anupama , Love Cassandra , Clasen‐Linde Erik , Knudsen Helle , Nielsen Signe Ledou , Gang Anne Ortved , Høgdall Estrid , Dave Sandeep , Nørgaard Peter 
Published: August 2019

AbstractIn large B‐cell lymphoma (LBCL), MYC translocation and MYC/BCL2 or MYC/BCL6 double hit (DH) are associated with poor prognosis, and there is an unmet need for novel treatment targets in this patient group. Treatments targeting the PD‐L1/PD‐1 pathway are still poorly elucidated in LBCL. PD‐L1 expression might predict response to treatment targeting the PD‐L1/PD‐1 pathway. We therefore investigated the relationship between PD‐L1 protein and mRNA expression levels and MYC and DH translocation in LBCL. We detected MYC, BCL2, and BCL6 translocation by fluorescent in situ hybridization in tissue samples from 130 patients randomly selected from two cohorts of patients with LBCL: 49 patients with MYC translocation of whom 36 had DH and 81 without MYC translocation. PD‐L1 protein expression was detected by immunohistochemistry (IHC) in tissue samples from 77 patients and PD‐L1 mRNA expression by next‐generation RNA sequencing (NGS) in another 77 patients. Twenty‐four patients overlapped, ie, were analysed with both IHC and NGS. Nonparametric tests were performed to evaluate intergroup differences. PD‐L1 protein expression level was significantly lower in patients with MYC (n = 42, median = 3.3%, interquartile range [IQR] 0.0‐10.8) or DH translocations (n = 31, median = 3.3%, IQR 0.0‐10.0) compared with patients with no MYC (n = 35, median = 16.7%, IQR 3.3‐30.0) or no DH translocations (n = 46, 13.3%, IQR 2.5‐30.0), P = .004 and P ≤ .001, respectively. PD‐L1 mRNA expression was also significantly lower in patients with MYC or DH translocations, P = .001 and P = .006, respectively. Higher PD‐L1 protein and mRNA expression levels were associated with non–germinal centre (GC) type compared with germinal centre B‐cell (GCB)‐type diffuse LBCL (DLBCL), P = .004 and P = .002, respectively. In conclusion, we report an association between low PD‐L1 expression and MYC and DH translocation in patients with LBCL. Our findings may indicate that patients with MYC or DH translocation may benefit less from treatment with PD‐L1/PD‐1‐inhibitors compared with patients without these translocations. This should be evaluated in larger, prospective, consecutive trials.
Three‐dimensional interventional photoacoustic imaging for biopsy needle guidance with a linear array transducer
Authors: Wang Hang , Liu Songde , Wang Tong , Zhang Chenxi , Feng Ting , Tian Chao 
Published: August 2019

AbstractNeedle placement is important for many clinical interventions, such as tissue biopsy, regional anesthesia and drug delivery. It is essential to visualize the spatial position of the needle and the target tissue during the interventions using appropriate imaging techniques. Based on the contrast of optical absorption, photoacoustic imaging is well suited for the guidance of interventional procedures. However, conventional photoacoustic imaging typically provides two‐dimensional (2D) slices of the region of interest and could only visualize the needle and the target when they are within the imaging plane of the probe at the same time. This requires great alignment skill and effort. To ease this problem, we developed a 3D interventional photoacoustic imaging technique by fast scanning a linear array ultrasound probe and stitching acquired image slices. in vivo sentinel lymph node biopsy experiment shows that the technique could precisely locate a needle and a sentinel lymph node in a tissue volume while a perfusion experiment demonstrates that the technique could visualize the 3D distribution of injected methylene blue dye underneath the skin at high temporal and spatial resolution. The proposed technique provides a practical way for photoacoustic image‐guided interventions.
Antimicrobial blue light for decontamination of platelets during storage
Authors: Lu Min , Dai TianHong , Hu SiSi , Zhang Qi , Bhayana Brijesh , Wang Li , Wu Mei X. 
Published: August 2019

AbstractPlatelet (PLT) storage is currently limited to 5 days in clinics in the United States, in part, due to an increasing risk for microbial contamination over time. In light of well‐documented antimicrobial activity of blue light (405‐470 nm), we investigated potentials to decontaminate microbes during PLT storage by antimicrobial blue light (aBL). We found that PLTs produced no detectable levels of porphyrins or their derivatives, the chromophores that specifically absorb blue light, in marked contrast to microbes that generated porphyrins abundantly. The difference formed a basis with which aBL selectively inactivated contaminated microbes prior to and during the storage, without incurring any harm to PLTs. In accordance with this, when contamination with representative microbes was simulated in PLT concentrates supplemented with 65% of PLT additive solution in a standard storage bag, all “contaminated” microbes tested were completely inactivated after exposure of the bag to 405 nm aBL at 75 J/cm2 only once. While killing microbes efficiently, this dose of aBL irradiation exerted no adverse effects on the viability, activation or aggregation of PLTs ex vivo and could be used repeatedly during PLT storage. PLT survival in vivo was also unaltered by aBL irradiation after infusion of aBL‐irradiated mouse PLTs into mice. The study provides proof‐of‐concept evidence for a potential of aBL to decontaminate PLTs during storage.
Three‐dimensional cryogels for biomedical applications
Authors: Razavi Mehdi , Qiao Yang , Thakor Avnesh S. 
Published: August 2019

AbstractCryogels are a subset of hydrogels synthesized under sub‐zero temperatures: initially solvents undergo active freezing, which causes crystal formation, which is then followed by active melting to create interconnected supermacropores. Cryogels possess several attributes suited for their use as bioscaffolds, including physical resilience, bio‐adaptability, and a macroporous architecture. Furthermore, their structure facilitates cellular migration, tissue‐ingrowth, and diffusion of solutes, including nano‐ and micro‐particle trafficking, into its supermacropores. Currently, subsets of cryogels made from both natural biopolymers such as gelatin, collagen, laminin, chitosan, silk fibroin, and agarose and/or synthetic biopolymers such as hydroxyethyl methacrylate, poly‐vinyl alcohol, and poly(ethylene glycol) have been employed as 3D bioscaffolds. These cryogels have been used for different applications such as cartilage, bone, muscle, nerve, cardiovascular, and lung regeneration. Cryogels have also been used in wound healing, stem cell therapy, and diabetes cellular therapy. In this review, we summarize the synthesis protocol and properties of cryogels, evaluation techniques as well as current in vitro and in vivo cryogel applications. A discussion of the potential benefit of cryogels for future research and their application are also presented.
Specific concentration of hyaluronan amide derivative induces osteogenic mineralization of human mesenchymal stromal cells: Evidence of RUNX2 and COL1A1 genes modulation
Authors: Paolella Francesca , Gabusi Elena , Manferdini Cristina , Schiavinato Antonella , Lisignoli Gina 
Published: August 2019

AbstractHyaluronic acid (HA) is an ideal material for tissue regeneration. The aim of this study was to investigate whether a hyaluronan amide derivative (HAD) can enhance the mineralization of human mesenchymal stem cells (hMSCs). Osteogenically induced hMSCs cultured with or without HAD at different concentrations (0.5 mg/ml or 1 mg/ml) were analyzed for mineral matrix deposition, metabolic activity, cellular proliferation, and the expression of 14 osteogenic genes. Unmodified HA (HYAL) was used as control. We demonstrated that only cells treated daily until day 28 with 0.5 mg/ml HAD, but not with 1 mg/ml of HAD and HYAL, showed a significant induction of mineralization at day 14 compared to the osteogenic control group. HAD at both concentrations tested, significantly decreased the expression of the proliferating marker MKI67 at day 2. By contrast, increased metabolic activity was induced only by HYAL from day 14. HAD at both concentrations significantly down modulated SNAI2, DLX5, RUNX2, COL1A1, and IBSP genes, while significantly up regulated COL15A1. The induction of mineralization of 0.5 mg/ml of HAD at day 14 was significantly dependent on a specific modulation of RUNX2 and COL1A1. Our data demonstrate that only 0.5 mg/ml of HAD, but not HYAL, modulated hMSCs osteogenic differentiation, suggesting that the physicochemical features and concentration of HA products could differently affect osteogenic maturation.
A bench‐top molding method for the production of cell‐laden fibrin micro‐fibers with longitudinal topography
Authors: Keijdener Hans , Konrad Jens , Hoffmann Bernd , Gerardo‐Nava José , Rütten Stephan , Merkel Rudolf , Vázquez‐Jiménez Jaime , Brook Gary A. , Jockenhoevel Stefan , Mela Petra 
Published: August 2019

AbstractTissue‐engineered constructs have great potential in many intervention strategies. In order for these constructs to function optimally, they should ideally mimic the cellular alignment and orientation found in the tissues to be treated. Here we present a simple and reproducible method for the production of cell‐laden pure fibrin micro‐fibers with longitudinal topography. The micro‐fibers were produced using a molding technique and longitudinal topography was induced by a single initial stretch. Using this method, fibers up to 1 m in length and with diameters of 0.2–3 mm could be produced. The micro‐fibers were generated with embedded endothelial cells, smooth muscle cell/fibroblasts or Schwann cells. Polarized light and scanning electron microscopy imaging showed that the initial stretch was sufficient to induce longitudinal topography in the fibrin gel. Cells in the unstretched control micro‐fibers elongated randomly in both the floating and encapsulated environments, whereas the cells in the stretched micro‐fibers responded to the introduced topography by adopting a similar orientation. Proof of concept bottom‐up tissue engineering (TE) constructs are shown, all displaying various anisotropic organization of cells within. This simple, economical, versatile and scalable approach for the production of highly orientated and cell‐laden micro‐fibers is easily transferrable to any TE laboratory.
Optimization of the catalytic support and membrane for the electrochemical reforming of ethanol in alkaline media
Authors: Calcerrada Ana Belén , de la Osa Ana Raquel , Romero Amaya , Valverde José Luis , de Lucas‐Consuegra Antonio , Dorado Fernando 
Published: August 2019

AbstractBACKGROUNDIn this work, the influence of the anodic catalyst carbonaceous support and the membrane on the electrochemical reforming of ethanol for hydrogen production in alkaline media has been studied. Physicochemical characterization and electrochemical activity measurements were performed for different palladium‐based anodic catalysts. The best anodic catalyst was scaled up to two different membrane electrode assemblies (MEAs) based on anion exchange membranes (AEMs): Tokuyama and KOH‐doped polybenzimidazole (PBI) membranes. In both systems, the influence of the temperature and the stability were evaluated for the electrochemical reforming of ethanol.RESULTSAmong the different investigated catalysts, palladium supported on non‐functionalized low‐surface nanofibers was the best anodic catalyst for the electrochemical reforming of ethanol in alkaline media, which was attributed to the specific physicochemical and textural properties of this material. In addition, the use of a Tokuyama membrane allowed to obtain the highest electrocatalytic activity in hydrogen production together with a suitable stability behavior. Under the optimized conditions, current density values up to 120 mA cm−2 at 1.4 V were obtained, leading to lower energy values for hydrogen production compared with those of water electrolysis in commercial alkaline electrolyzers.CONCLUSIONThe choice of palladium supported on non‐functionalized nanofibers as anodic catalyst and a Tokuyama membrane allows to obtain the best MEA configuration for the electrochemical reforming of ethanol for hydrogen production. © 2019 Society of Chemical Industry
Design, Synthesis, and Pharmacological Assay of Novel Compounds Based on Pyridazine Moiety as Potential Antitumor Agents
Authors: Ali Yasmeen M. , Ismail Mahmoud F. , Abu El‐Azm Fatma S. M. , Marzouk Magda I. 
Published: August 2019

In an endeavor to develop antitumor agents, we made a credible survey regarding synthesis, structure, and pharmacological assay of novel pyridazine derivatives, so that 2‐((6‐(4‐chloro‐3‐methylphenyl)pyridazin‐3‐yl)oxy)acetohydrazide 3 was utilized as scaffold to build novel compounds 4–19 by reaction with various electrophilic reagents, followed by determination and explanation atropisomerism phenomena and tauomerism ratio such as keto‐enol and lactam–lactim tautomers for some synthesized compounds. In vitro, these compounds were screened for antitumor efficacy versus two cell lines, namely, hepatocellular carcinoma and mammary gland breast cancer, by using MTT assay. Among the examined compounds, compound 16 was exhibited promising potent activity (IC50 = 8.67 ± 0.7 μM) versus HepG2 cell line. Meanwhile, compounds 3 and 16 were manifested the very highest efficacy (IC50 = 5.68 ± 0.6 and 9.41 ± 0.9 μM) versus MCF‐7 cell line.
Jordan operator algebras revisited
Authors: Blecher David P. , Wang Zhenhua 
Published: August 2019

AbstractJordan operator algebras are norm‐closed spaces of operators on a Hilbert space with for all . In two recent papers by the authors and Neal, a theory for these spaces was developed. It was shown there that much of the theory of associative operator algebras, in particular, surprisingly much of the associative theory from several recent papers of the first author and coauthors, generalizes to Jordan operator algebras. In the present paper we complete this task, giving several results which generalize the associative case in these papers, relating to unitizations, real positivity, hereditary subalgebras, and a couple of other topics. We also solve one of the three open problems stated at the end of our earlier joint paper on Jordan operator algebras.
Validity of the “Rate‐a‐Plate” Method to Estimate Energy and Protein Intake in Acutely Ill, Hospitalized Patients
Authors: Dekker Ingeborg M. , Langius Jacqueline A. E. , Stelten Stephanie , de Vet Henrica C. W. , Kruizenga Hinke M. , de van der Schueren Marian A. E. 
Published: August 2019

AbstractBackgroundPrevalence of malnutrition in hospitals has been reported around 20% and increases during hospitalization. The “Rate‐a‐Plate” method has been developed to monitor dietary intake and identify patients whose nutrition status deteriorates during hospitalization, but has not yet been validated. The objective was to study the validity and reliability of the method (phase 1) and redesign and revalidate a revised version (phase 2).MethodsDetailed food records provided a reference method. A priori difference of >20% in energy or protein between the reference and the “Rate‐a‐Plate” method was determined as clinically relevant. Intraclass correlation coefficients were used to determine the reliability.ResultsIn phase 1, 24 patients were included with a total 67 test days. In phase 2, 14 patients were included, 28 test days. In phase 1, the “Rate‐a‐Plate” method underestimated intake by 422 kcal (29%, ICC 0.349, 95% CI 304–541) and 5.7 g protein (10%, ICC 0.511, 95% CI 0.0–11.5). Underestimation was found in 65% and 23% for energy and protein intake, respectively. Underestimation was higher when patients had higher intake. In phase 2, underestimation was 109 kcal (7%, ICC 0.788, 95% CI −273 to 56) and 3.7 g protein (6%, ICC 0.905, 95% CI −8.4 to 1.0). In 32% and 21% of the cases, energy and protein intake were underestimated.ConclusionThe revised version of the “Rate‐a‐Plate” method is a valid method to monitor energy and protein intake of hospitalized patients and can be filled out by nutrition assistants. A larger validation study is required.
A Systematic Review of Medical Nutrition Therapy Guidelines for Liver Cirrhosis: Do We Agree?
Authors: Theodoridis Xenophon , Grammatikopoulou Maria G. , Petalidou Arianna , Kontonika Stamatia‐Maria , Potamianos Spyros P. , Bogdanos Dimitrios P. 
Published: August 2019

AbstractBackgroundNutrition can play a significant role in the management of liver cirrhosis and its complications. However, adherence to the clinical practice guidelines (CPGs) is essential for the practice of evidence‐based medicine and is considered as a health‐quality indicator.MethodsA systematic search was conducted in scientific databases, and retrieved CPGs fulfilling the inclusion criteria were independently reviewed and appraised from 3 experienced researchers, based on the Appraisal of Guidelines for Research and Evaluation II instrument.ResultsA total of 13 relevant CPGs were retrieved, published by 7 associations/societies, focusing on the nutrition management (enteral nutrition and/or parenteral nutrition) on cirrhosis, decompensated cirrhosis, liver transplantation, and cirrhosis‐related complications. Most CPGs scored low in the stakeholder, rigor of development, and applicability domains. Half of the CPGs recognized the need for counseling patients with cirrhosis on nutrition‐related issues. Small meals spread throughout the day, including a late‐night snack, were suggested, with protein intake ranging between 1.2 and 1.5 g/kg of body weight. In ascites, Na restriction recommendation appeared unanimous.ConclusionsSeveral shortcomings and bias were recognized in cirrhosis‐related medical nutrition therapy CPGs, indicating the need of improving CPG methodology.
A numerical method for a nonlinear structured population model with an indefinite growth rate coupled with the environment
Authors: Ackleh Azmy S. , Miller Robert L. 
Published: August 2019

AbstractA numerical method is developed for a general structured population model coupled with the environment dynamics over a bounded domain where the individual growth rate changes sign. Sign changes notably exhibit nonlocal dependence on the population density and environmental factors (e.g., resource availability and other habitat variables). This leads to a highly nonlinear PDE describing the time‐evolution of the population density coupled with a nonlinear‐nonlocal system of ODEs describing the environmental time‐dynamics. Stability of the finite‐difference numerical scheme and its convergence to the unique weak solution are proved. Numerical experiments are provided to demonstrate the performance of the finite difference scheme and to illustrate a range of biologically relevant potential applications.
Effect of an intervention to improve the prescription of antifungals in pediatric hematology‐oncology
Authors: Santiago‐García Begoña , Rincón‐López Elena María , Ponce Salas Beatriz , Aguilar de la Red Yurena , Garrido Colino Carmen , Martínez Fernández‐Llamazares Cecilia , Saavedra‐Lozano Jesús , Hernández‐Sampelayo Matos Teresa ,   the POPA Study Group
Published: August 2019

AbstractBackgroundThe use of antifungals has expanded in pediatric hematology‐oncology, and the need to develop pediatric‐based surveillance and education activities is becoming crucial. The aims of this study were to evaluate the impact of a multidisciplinary protocol on the adequacy of antifungal prescription in a pediatric hematology‐oncology unit and to assess the effect of an educational intervention to improve the knowledge of prescribing pediatricians over time.MethodsA multidisciplinary team established a protocol for the management of invasive fungal disease (IFD). The use of antifungals before (January 2012‐May 2013) and after the protocol (June 2013‐December 2015) was evaluated. Prescribing pediatricians attended a training course on IFD and were evaluated before 0, 6, and 12 months after the intervention.ResultsDuring the study period, antifungal agents were used in 185 episodes (56 children, 39.3% females), and were administered as prophylaxis (58.9%), empiric (34.6%), or targeted therapy (6.5%). Antifungal prescriptions were inadequate in 7% of the episodes, related to drug selection (53.8%), dosage (38.5%) and route of administration (7.7%). After protocol implementation, inadequate prescriptions decreased 9.9% (15.2% vs 5.3%; P = .04). Following the educational activity, the percentage of adequate responses to the questionnaire improved significantly compared to baseline, and persisted over time (19.7% improvement at 0 months [P < .0001]; 21.1% at 6 months [P < .0001]; 16.6% at 12 months [P = .002]).ConclusionsThe establishment of multidisciplinary protocols and education activities improved the quality of antifungal prescription and the knowledge of prescribers regarding antifungal therapy. Therefore, these activities may be important for the implementation of antifungal stewardship programs in pediatrics.