bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel population of memory‐activated natural killer cells associated with low parasitaemia in Plasmodium falciparum‐exposed sickle‐cell trait children
Authors: Loiseau Claire , Doumbo Ogobara K , Traore Boubacar , Brady Jamie L , Proietti Carla , de Sousa Karina P , Crompton Peter D , Doolan Denise L
Published: April 2020

Objectives

The sickle‐cell trait phenotype is associated with protection from malaria. Multiple molecular mechanisms have been proposed to explain this protection, but the role of the host immune system has been poorly investigated. We hypothesised that cellular immunity to malaria may develop differently in sickle‐cell trait children (HbAS) and children with normal haemoglobin (HbAA) repeatedly exposed to Plasmodium falciparum (Pf).

Methods

Paired samples collected prior to the Pf transmission season and during the first malaria episode of the ensuing transmission season from HbAS and HbAA children were analysed by multiplex bead‐based assay and comprehensive multi‐dimensional flow cytometry profiling.

Results

Cellular immune profiles were enriched in HbAS relative to HbAA children before the start of the Pf transmission season, with a distinct NK subset. These cells were identified as a novel subset of memory‐activated NK cells characterised by reduced expression of the ecto‐enzyme CD38 as well as co‐expression of high levels of HLA‐DR and CD45RO. The frequency of this NK subset before the transmission season was negatively correlated with parasite density quantified during the first malaria episode of the ensuing transmission season. Functional assessment revealed that these CD38dim CD45RO+ HLA‐DR+ NK cells represent a important source of IFN‐γ.

Conclusion

Our data suggest that this novel memory‐activated NK cell subset may contribute to an accelerated and enhanced IFN‐γ‐mediated immune response and to control of parasite density in individuals with the sickle‐cell trait. This distinct cellular immune profile may contribute to predispose HbAS children to a relative protection from malaria.
Competition influences tree growth, but not mortality, across environmental gradients in Amazonia and tropical Africa
Authors: Rozendaal Danaë M. A. , Phillips Oliver L. , Lewis Simon L. , Affum‐Baffoe Kofi , Alvarez-Davila Esteban , Andrade Ana , Aragão Luiz E. O. C. , Araujo‐Murakami Alejandro , Baker Timothy R. , Bánki Olaf , Brienen Roel J. W. , Camargo José Luis C. , Comiskey James A. , Djuikouo Kamdem Marie Noël , Fauset Sophie , Feldpausch Ted R. , Killeen Timothy J. , Laurance William F. , Laurance Susan G. W. , Lovejoy Thomas , Malhi Yadvinder , Marimon Beatriz S. , Marimon Junior Ben‐Hur , Marshall Andrew R. , Neill David A. , Núñez Vargas Percy , Pitman Nigel C. A. , Poorter Lourens , Reitsma Jan , Silveira Marcos , Sonké Bonaventure , Sunderland Terry , Taedoumg Hermann , ter Steege Hans , Terborgh John W. , Umetsu Ricardo K. , van der Heijden Geertje M.F. , Vilanova Emilio , Vos Vincent , White Lee J. T. , Willcock Simon , Zemagho Lise , Vanderwel Mark C.
Published: April 2020

Competition among trees is an important driver of community structure and dynamics in tropical forests. Neighboring trees may impact an individual tree’s growth rate and probability of mortality, but large‐scale geographic and environmental variation in these competitive effects has yet to be evaluated across the tropical forest biome. We quantified effects of competition on tree‐level basal area growth and mortality for trees ≥10‐cm diameter across 151 ~1‐ha plots in mature tropical forests in Amazonia and tropical Africa by developing nonlinear models that accounted for wood density, tree size, and neighborhood crowding. Using these models, we assessed how water availability (i.e., climatic water deficit) and soil fertility influenced the predicted plot‐level strength of competition (i.e., the extent to which growth is reduced, or mortality is increased, by competition across all individual trees). On both continents, tree basal area growth decreased with wood density and increased with tree size. Growth decreased with neighborhood crowding, which suggests that competition is important. Tree mortality decreased with wood density and generally increased with tree size, but was apparently unaffected by neighborhood crowding. Across plots, variation in the plot‐level strength of competition was most strongly related to plot basal area (i.e., the sum of the basal area of all trees in a plot), with greater reductions in growth occurring in forests with high basal area, but in Amazonia, the strength of competition also varied with plot‐level wood density. In Amazonia, the strength of competition increased with water availability because of the greater basal area of wetter forests, but was only weakly related to soil fertility. In Africa, competition was weakly related to soil fertility and invariant across the shorter water availability gradient. Overall, our results suggest that competition influences the structure and dynamics of tropical forests primarily through effects on individual tree growth rather than mortality and that the strength of competition largely depends on environment‐mediated variation in basal area.
Habitat fragmentation changes top‐down and bottom‐up controls of food webs
Authors: Wang Rong , Zhang Xin , Shi Yi‐Su , Li Yuan‐Yuan , Wu Jianguo , He Fangliang , Chen Xiao‐Yong
Published: April 2020

Top‐down and bottom‐up controls regulate the structure and stability of ecosystems, but their relative roles in terrestrial systems have been debated. Here we studied a hydro‐inundated land‐bridge system in subtropical China and tested the relative importance of these two controls in determining the rodent‐mediated regeneration of a locally dominant tree species. Our results showed that both controls operated in terrestrial habitats and that their relative importance switched as habitat size changed. Habitat loss initially removed predators of rodents that released rodent populations and triggered massive seed predation (top‐down control), leading to reduced seedling establishment. A further reduction in habitat size led to decrease in rodent population that was supposed to increase seedling survival of the tree species, but the decline in habitat size deteriorated the abiotic environments (bottom‐up control) that severely prevented seedling recruitment. As the ongoing global land use change is creating increasing number of small‐sized forest fragments, our findings provide novel insights into the restoration of seriously fragmented forests.
Fe3O4@MOF Magnetic Nanocomposites: Synthesis and Applications
Authors: Aghayi‐Anaraki Milad , Safarifard Vahid
Published: April 2020

In this review, we gather a great deal of information about magnetic nanocomposites, which are made from the combination of Fe3O4 magnetic nanoparticles (MNPs) and metal‐organic frameworks (MOFs). Due to the high saturation magnetization, biocompatibility, low toxicity, stability, and cost‐effectiveness, MNPs have attracted a lot of interest in recent years. Furthermore, MOFs, which are porous materials, formed by the connection between organic linkers and metal ions. The combination of MNPs and MOFs results in the formation of magnetic framework composites (MFCs). The information about the MFCs is classified according to their applications and we provide brief information about the synthesizing of these materials. MFCs have a wide array of uses in various fields such as catalysis, biomedical, extraction, etc. We discussed these applications in detail. This information has been amassed to provide researchers with a proper chance to obtain enough information about these materials. Researchers are also able to become aware of some drawbacks in each field, and they can propose some solutions to overcome those drawbacks. We aimed to prepare a well‐organized review to respond to the desire of using MFCs in different fields.
Catecholate‐Based Helicates
Authors: Albrecht Markus
Published: April 2020

Catechol is a bidentate ligand for metal coordination which is well suited for the formation of helicates and related metallosupramolecular complexes. The development of the self‐assembly and stereochemistry of helicates based on catechol ligands in the last 25 years is discussed. Unsaturated, heteronuclear and hierarchical helicates as well as molecular switches based on catecholate helicates are covered.
Constitutive deletion of astrocytic connexins aggravates kainate‐induced epilepsy
Authors: Deshpande Tushar , Li Tingsong , Henning Lukas , Wu Zhou , Müller Julia , Seifert Gerald , Steinhäuser Christian , Bedner Peter
Published: April 2020

The astroglial gap junctional network formed by connexin (Cx) channels plays a central role in regulating neuronal activity and network synchronization. However, its involvement in the development and progression of epilepsy is not yet understood. Loss of interastrocytic gap junction (GJ) coupling has been observed in the sclerotic hippocampus of patients with mesial temporal lobe epilepsy (MTLE) and in mouse models of MTLE, leading to the suggestion that it plays a causative role in the pathogenesis. To further elucidate this clinically relevant question, we investigated consequences of astrocyte disconnection on the time course and severity of kainate‐induced MTLE with hippocampal sclerosis (HS) by comparing mice deficient for astrocytic Cx proteins with wild‐type mice (WT). Continuous telemetric EEG recordings and video monitoring performed over a period of 4 weeks after epilepsy induction revealed substantially higher seizure and interictal spike activity during the chronic phase in Cx deficient versus WT mice, while the severity of status epilepticus was not different. Immunohistochemical analysis showed that, despite the elevated chronic seizure activity, astrocyte disconnection did not aggravate the severity of HS. Indeed, the extent of CA1 pyramidal cell loss was similar between the experimental groups, while astrogliosis, granule cell dispersion, angiogenesis, and microglia activation were even reduced in Cx deficient as compared to WT mice. Interestingly, seizure‐induced neurogenesis in the adult dentate gyrus was also independent of astrocytic Cxs. Together, our data indicate that constitutive loss of GJ coupling between astrocytes promotes neuronal hyperexcitability and attenuates seizure‐induced histopathological outcomes.
Comprehensive Health‐State Utilities in Contemporary Patients With Cirrhosis
Authors: Foster Chelsey , Baki Jad , Nikirk Samantha , Williams Sydni , Parikh Neehar D. , Tapper Elliot B.
Published: April 2020

Cost‐effectiveness analysis depends on generalizable health‐state utilities. Unfortunately, the available utilities for cirrhosis are dated, may not reflect contemporary patients, and do not capture the impact of cirrhosis symptoms. We aimed to determine health‐state utilities for cirrhosis, using both the standard gamble (SG) and visual analog scale (VAS). We prospectively enrolled 305 patients. Disease severity (Child‐Pugh [Child] class, Model for End‐Stage Liver Disease with sodium [MELD‐Na] scores), symptom burden (sleep quality, cramps, falls, pruritus), and disability (activities of daily living) were assessed. Multivariable models were constructed to determine independent clinical associations with utility values. The mean age was 57 ± 13 years, 54% were men, 30% had nonalcoholic steatohepatitis, 26% had alcohol‐related cirrhosis, 49% were Child class A, and the median MELD‐Na score was 12 (interquartile range [IQR], 8‐18). VAS displayed a normal distribution with a wider range than SG. The Child‐specific SG‐derived utilities had a median value of 0.85 (IQR, 0.68‐0.98) for Child A, 0.78 (IQR, 0.58‐0.93) for Child B, and 0.78 (IQR, 0.58‐0.93) for Child C. VAS‐derived utilities had a median value of 0.70 (IQR, 0.60‐0.85) for Child A, 0.61 (IQR, 0.50‐0.75) for Child B, and 0.55 (IQR, 0.40‐0.70) for Child C. VAS and SG were weakly correlated (Spearman's rank correlation coefficient, 0.12; 95% confidence interval, 0.006‐0.23). In multivariable models, disability, muscle cramps, and MELD‐Na were significantly associated with SG utilities. More clinical covariates were significantly associated with the VAS utilities, including poor sleep, MELD‐Na, disability, falls, cramps, and ascites. Conclusion: We provide health‐state utilities for contemporary patients with cirrhosis as well as estimates of the independent impact of specific symptoms on each patient’s reported utility.
Prognostic significance of infectious episodes occurring during first‐line therapy for diffuse large B‐cell lymphoma ‐ A nationwide cohort study
Authors: Clausen Michael R. , Ulrichsen Sinna P. , Juul Maja B. , Poulsen Christian B. , Iversen Brian , Pedersen Per T. , Madsen Jakob , Pedersen Robert S. , Josefsson Pär L. , Gørløv Jette S. , Nørgaard Mette , d'Amore Francesco
Published: April 2020

Infections during first‐line therapy for DLBCL are often associated with chemotherapy dose reductions and increased mortality. Systemic infections have also been suggested as beneficial promotors of immunological responses. However, whether there is an association between the timing of an infectious episode and outcome during treatment has not yet been clarified. We investigated how the occurrence and timing of infectious episodes during the first line of treatment for “de novo” DLBCL influenced patient outcome. We used data on DLBCL patients from the Danish Lymphoma Registry, the Danish National Patient Registry, and the Danish National Pathology Registry. Infections were categorized according to type (ICD‐10) and time of occurrence after treatment start. “Early” infections were defined as occurring between days 7 and 42 and “late” infections between days 100 and 150 from treatment start. Patients experiencing both “early and late” infections were categorized separately. We used multivariable Cox regression and Kaplan‐Meier estimates to assess the association between infections and survival adjusting for NCCN‐IPI, sex, comorbidity, and rituximab treatment. We identified 3546 patients, median age 65 years (IQR 56,73). Infectious episodes occurred in 1171 (33%) patients, of which 666 had “early,” 303 “late,” and 202 both “early and late” events. Patients without registered infections had a 5‐year overall survival (OS) rates of 74%. Those with “early,” “late,” or “early+late” had 5‐year OS of 65%, 62%, and 53%, respectively. Compared with patients without any registered infections, hazard rate ratios (HR) were 1.24 (95% CI 1.05‐1.47), 1.32 (95% CI 1.06–1.63), and 1.59 (95% CI 1.27‐2.00), respectively, in the multivariable model. We observed that infectious episodes during first‐line treatment for “de novo” DLBCL occurred in 44% of the patients. Irrespective of timing, patients with infectious episodes had an inferior outcome compared to those without. Outcome patterns were similar for patients registered with sepsis.
Effect of venlafaxine dosage, valproic acid concentration, sex, and age on steady state dose‐corrected concentrations of venlafaxine and O‐desmethylvenlafaxine: A retrospective analysis of therapeutic drug monitoring data in a Chinese population
Authors: Wang Zhan‐zhang , Deng Shu‐hua , Lu Hao‐yang , Li Lu , Zhu Xiu‐qing , Hu Jin‐qing , Xie Huan‐shan , Chen Hong‐zhen , Chen Yu‐qing , Zhang Ming , Fang Zi‐yan , Wen Yu‐guan , Shang De‐wei
Published: April 2020

Purpose

This study aimed to investigate the influence of diagnosis, body weight, sex, age, smoking, formulations, and concomitant drugs on steady‐state dose‐corrected serum concentrations (C/D) of venlafaxine (VEN) and O‐desmethylvenlafaxine (ODV).

Methods

A retrospective analysis of therapeutic drug monitoring (TDM) was carried out. Patients' demographic data, therapeutic regimens, and concentrations were collected.

Results

We included 91 verified samples from 80 patients. Females had by average 13% smaller body weight, 50% higher C/D of VEN, and VEN + ODV and 25% smaller ODV/VEN than males. Patients >60 years had by average 33–59% higher C/D levels of ODV and VEN + ODV than younger patients. The concomitant use of valproic acid caused an average 51% higher C/D of ODV and a 2.2‐fold larger ODV/VEN, while clozapine was related with 40% smaller ratio of ODV/VEN and 38% lower C/D levels of ODV. Positive correlations were detected between valproic acid concentrations and the C/D of VEN and VEN + ODV. In a multiple linear regression analysis, variance in the C/D of VEN + ODV was partly attributed to the daily dose of VEN, sex, age and valproic acid concentration.

Conclusion

Our results suggested daily dose of VEN, sex, age, and valproic acid as indicators for the C/D of VEN + ODV in Chinese patients. TDM as a valuable tool was suggested in elderly female patients and patients receiving polypharmacy.
Reducing data acquisition for light‐sheet microscopy by extrapolation between imaged planes
Authors: Shemesh Ziv , Chaimovich Gal , Gino Liron , Ozana Nisan , Nylk Jonathan , Dholakia Kishan , Zalevsky Zeev
Published: April 2020

Light‐sheet fluorescence microscopy (LSFM) is a powerful technique that can provide high‐resolution images of biological samples. Therefore, this technique offers significant improvement for three‐dimensional (3D) imaging of living cells. However, producing high‐resolution 3D images of a single cell or biological tissues, normally requires high acquisition rate of focal planes, which means a large amount of sample sections. Consequently, it consumes a vast amount of processing time and memory, especially when studying real‐time processes inside living cells. We describe an approach to minimize data acquisition by interpolation between planes using a phase retrieval algorithm. We demonstrate this approach on LSFM data sets and show reconstruction of intermediate sections of the sparse samples. Since this method diminishes the required amount of acquisition focal planes, it also reduces acquisition time of samples as well. Our suggested method has proven to reconstruct unacquired intermediate planes from diluted data sets up to 10× fold. The reconstructed planes were found correlated to the original preacquired samples (control group) with correlation coefficient of up to 90%. Given the findings, this procedure appears to be a powerful method for inquiring and analyzing biological samples.
Frizzled 6 disruption suppresses osteoblast differentiation induced by nanotopography through the canonical Wnt signaling pathway
Authors: Abuna Rodrigo Paolo Flores , Oliveira Fabiola Singaretti , Adolpho Leticia Faustino , Fernandes Roger Rodrigo , Rosa Adalberto Luiz , Beloti Marcio Mateus
Published: April 2020

This study aimed to investigate if wingless‐related integration site (Wnt) signaling participates in the high osteogenic potential of titanium with nanotopography (Ti‐Nano). We showed that among the several components of the Wnt signaling pathway, Frizzled 6 (Fzd6) was the transcript most intensely modulated by nanotopography compared with the untreated Ti surface (Ti‐Machined). Then, we investigated whether and how Fzd6 participates in the regulation of osteoblast differentiation caused by nanotopography. The Fzd6 silencing with CRISPR–Cas9 transfection in MC3T3‐E1 cells induced a more pronounced inhibition of osteoblast differentiation of cells cultured on nanotopography than those cultured on Ti‐Machined. The analysis of the expression of calcium‐calmodulin‐dependent protein kinase II and β‐catenin demonstrated that Fzd6 disruption inhibited the osteoblast differentiation induced by Ti‐Nano by preventing the activation of Wnt/β‐catenin but not that of Wnt/Ca2+ signaling, which is usually triggered by the receptor Fzd6. These findings elucidate the biological function of Fzd6 as a receptor that triggers Wnt/β‐catenin signaling and the cellular mechanisms modulated by nanotopography during osteoblast differentiation.
Aurora kinase inhibitor restrains STAT5‐activated leukemic cell proliferation by inducing mitochondrial impairment
Authors: Wang Jin‐Xing , Zhang Ling , Huang Ze‐Wei , Zhang Xue‐Ning , Jiang Yan‐Yan , Liu Fang‐Jie , Long Liang , Xue Man‐Jie , Lu Gui , Liu Quentin , Long Zi‐Jie
Published: April 2020

Current chemotherapy regimens on acute myeloid leukemia (AML) still have some drawbacks, such as intolerance and drug resistance, which calls need for the development of targeted therapy. Signal transducer and activator of transcription 5 (STAT5) is often overexpressed or abnormally activated in leukemia and involved in cell self‐renewal, proliferation, and stress adaptation. Overexpressed Aurora A (AURKA) is associated with poor prognosis in tumors, and inhibitors against AURKA are already in clinical trials. However, it has rarely been reported whether AURKA inhibitors restrain STAT5‐activated leukemia cells. In this study, we constructed STAT5 constitutively activated (cS5) cells and found that STAT5 promoted cell proliferation and colony formation. Moreover, cS5 cells showed elevated reactive oxygen species (ROS) and adenosine triphosphate (ATP) levels, which indicated higher mitochondrial metabolism in cS5 cells. A novel AURKA inhibitor AKI604 was synthesized and showed significant inhibitory effects to the proliferation and colony formation in both STAT5 constitutively activated and nonactivated AML cells. AKI604 induced mitochondrial impairment, leading to the disruption of mitochondrial membrane potential and the elevation of ROS as well as cellular calcium (Ca2+) levels. AKI604 could also decline basal oxygen consumption rate and ATP biosynthesis, indicating the damage of oxidative phosphorylation. Furthermore, AKI604 exhibited significant antitumor effect in the HL‐60 cS5 xenograft model of the BALB/c nude mice without an obvious influence on mice body weight and other healthy indicators. This study suggested that AKI604 was a potential strategy to overcome STAT5‐induced leukemic proliferation in AML treatment by inducing mitochondrial impairment.
Adipose‐derived stem cells: An appropriate selection for osteogenic differentiation
Authors: Shafaei Hajar , Kalarestaghi Hossein
Published: April 2020

Mesenchymal stem cells (MSCs) are a major component of various forms of tissue engineering. MSCs have self‐renewal and multidifferential potential. Osteogenic differentiation of MSCs is an area of attention in bone regeneration. One form of MSCs are adipose‐derived stem cells (ASCs), which can be simply harvested and differentiated into several cell lineages, such as chondrocytes, adipocytes, or osteoblasts. Due to special properties, ASCs are frequently used in vitro and in vivo bone regeneration. Identifying factors involved in osteogenic differentiation of ASCs is important for better understanding the mechanism of osteogenic differentiation. Different methods are used to stimulate osteogenesis of ASCs in literature, including common osteogenic media, growth factors, hormones, hypoxia, mechanical and chemical stimuli, genetic modification, and nanotechnology. This review article provides an overview describing the isolation procedure, characterization, properties, current methods for osteogenic differentiation of ASCs, and their basic biological mechanism.
Glucose, glycolysis, and neurodegenerative diseases
Authors: Tang Bor Luen
Published: April 2020

Prolonged survival of a typical postmitotic neuron hinges on a balance between multiple processes, among these are a sustenance of ATP production and protection against reactive oxygen species. In neuropathological conditions, mitochondrial defects often lead to both a drop in ATP levels, as well as increase reactive oxygen species production from inefficient electron transport processes and NADPH‐oxidases activities. The former often resulted in the phenomenon of compensatory aerobic glycolysis. The latter stretches the capacity of the cell's redox buffering capacity, and may lead to damages of key enzymes involved in energy metabolism. Several recent reports have indicated that enhancing glucose availability and uptake, as well as increasing glycolytic flux via pharmacological or genetic manipulation of glycolytic enzymes, could be protective in animal models of several major neurodegenerative diseases, including Parkinson's disease, Huntington's disease, and Amyotrophic lateral sclerosis. Activation of canonical Wnt signaling, which improves disease symptoms in mouse models of Alzheimer's disease also appears to work via an elevation of glycolytic enzymes and enhance glucose metabolism. Here, I discuss these findings and the possible underlying mechanisms of how an increase in glucose uptake and glycolysis could be neuroprotective. Increased glycolytic production of ATP would help alleviate energy deficiency, and ATP's hydrotropic effect may enhance solubility and clearance of toxic aggregates prevalent in many neurodegenerative diseases. Furthermore, channeling of glucose into the Pentose Phosphate Pathway would increase the redox buffering capacity of the cell.
Runoff water quantity and quality data from native tallgrass prairie and crop–livestock systems in Oklahoma between 1977 and 1999
Authors: Nelson Amanda M. , Moriasi Daniel N. , Fortuna Ann‐Marie , Steiner Jean L. , Starks Patrick J. , Northup Brian , Garbrecht Jurgen
Published: April 2020

Erosion and sedimentation pose serious threats to soil and water quality worldwide, including in the U.S. southern Great Plains. To better understand these processes in agricultural landscapes, eight 1.6‐ha watersheds were established and instrumented in 1976 at the USDA‐ARS Grazinglands Research Laboratory, ∼50 km west of Oklahoma City near El Reno, OK, to measure precipitation and surface runoff quantity and quality. Prior to construction, all watersheds were in native grass, primarily big bluestem (Andropogon gerardiiVitman.), little bluestem [Schizachyrium scoparium(Michx.) Nash], and Indiangrass [Sorghastrum nutans(L.) Nash]; afterwards, four of the eight watersheds were cropped initially into winter wheat (Triticum aestivumL.) (two conventionally tilled and two minimally or no‐till). Although there have been many peer‐reviewed papers from the Water Resources and Erosion (WRE) watersheds, none included all the datasets collected during the period 1977–1999. The objectives of this paper were (a) to present and discuss all archived historical data, including methods of collection and analysis, (b) to provide summary analyses of the variability in each dataset, and (c) to provide details about how to access these datasets. These datasets are valuable resources to improve modeling in relation to land use and management changes, climate variability, and other environmental factors and may be useful in developing strategies to mitigate environmental impacts of agricultural systems. They are available athttps://doi.org/10.15482/USDA.ADC/1518421.
On the maximum number of copies of H in graphs with given size and order
Authors: Gerbner Dániel , Nagy Dániel T. , Patkós Balázs , Vizer Máté
Published: April 2020

We study the maximum number of copies of a graph in graphs with a given number of vertices and edges. We show that for any fixed graph is asymptotically realized by the quasi‐clique provided that the edge density is sufficiently large. We also investigate a variant of this problem, when the host graph is bipartite.
Synthesis of novel heterocyclic compounds containing pyrimidine nucleus using the Biginelli reaction: Antiproliferative activity and docking studies
Authors: Çağlar Yavuz Sevtap , Akkoç Senem , Türkmenoğlu Burçin , Sarıpınar Emin
Published: April 2020

In a single reaction step, pyrimidine derivatives (4a‐p) were synthesized from the triple reaction of aromatic aldehydes (1), ethyl cyanoacetate (2), and some guanyl hydrazone derivatives (3a‐n). These compounds were tested as in vitro against two types of cancerous cell lines, namely, a human colon cancerous cell line (DLD‐1) and a human breast cancerous cell line (MDA‐MB‐231). According to the obtained results, nearly all the compounds have cytotoxic activity in the tested cell lines. Especially, the compounds 4j, 4k, and 4n had a significant effect against DLD‐1. Furthermore, compounds 4g, 4m, and 4o exhibited lower IC50 values compared to other synthesized compounds against MDA‐MB‐231. We hope that these compounds can be improved as anticancer agents in the future. Molecular docking was performed according to both topoisomerase I and N‐acetyltransferase 1 proteins to examine theoretically the binding mode and site of pyrimidine compounds having the best activity.
A Self‐Determination Approach to Understanding Individual Values as an Interaction Condition on Employees' Innovative Work Behavior in the High‐Tech Industry
Authors: Wang Zheni , Gao Mengchan , Panaccio Alexandra
Published: April 2020

Drawing on self‐determination theory (SDT; E.L. Deci & R.M. Ryan, 1985, 2000) and using corporate samples (N = 284; 63% Male; Mean Age = 34,SD = 6.09) from high‐tech firms in China, this empirical study explored the path model from satisfaction of the basic psychological needs for autonomy, competence, and relatedness, through autonomous motivation to employees' innovative work behavior (“IWB”; J. De Jong & D. Den Hartog, 2010). It also simultaneously examined the interactions between autonomous work motivation and individual values (collectivism, H.C. Triandis (1995); uncertainty avoidance, R. J. House, P. J. Hanges, M. Javidan, P. W. Dorfman, & V. Gupta (2004); and power distance, J. Farh, R.D. Hackett, & J. Liang (2007)) in the conditioned path model. The regression results obtained from conditional PROCESS analysis (A.F. Hayes, 2013, 2018) suggest that basic psychological needs satisfaction is positively related to employees' IWB via autonomous motivation, but that these indirect effects were weaker when employees' power distance value orientation was high. Implications, limitations, and future research directions are discussed.
Treadmill exercise facilitated rotator cuff healing is coupled with regulating periphery neuropeptides expression in a murine model
Authors: Zhang Tao , Chen Yang , Chen Can , Li Shengcan , Xiao Han , Wang Linfeng , Hu Jianzhong , Lu Hongbin
Published: April 2020

Postoperative exercise has been found able to accelerate bone‐tendon (B‐T) healing. In this study, we systematically compared tendon‐to‐bone healing in mice subjected to postoperative treadmill exercise and free cage recovery in a murine rotator cuff repair model. Specifically, C57BL/6 mice underwent unilateral supraspinatus tendon (SST) detachment and repair were randomly allocated into treadmill group and control group. Treadmill group received daily treadmill running initiated from postoperative day 7 while the control group was allowed free cage activity. Mice were euthanized at postoperative 4 and 8 weeks for synchrotron radiation micro‐computed tomography (SR‐μCT), histology and biomechanical tests to investigate the effect of treadmill running on B‐T healing. The results indicated that treadmill running initiated at day 7 postoperatively was able to accelerate B‐T healing, as evidenced by better tendon‐to‐bone maturation and increased mechanical property. Recent studies show that peripheral neuropeptides are closely associated with musculoskeletal tissue repair. We furtherly conducted quantitative reverse transcription‐polymerase chain reaction and immunofluorescence staining to investigate the temporal‐spatial expression of calcitonin gene‐related peptide (CGRP), substance P (SP), and peripheral neuropeptide Y (NPY) to verify whether they are related to rotator cuff healing. Our results show increased expression of CGRP, SP, and NPY at the healing site under the effect of mechanical stimulation. In conclusion, delayed postoperative exercise with moderate strength appears to accelerate the early phase of B‐T healing, a process that may prove to be linked to increased expression of periphery neuropeptides known to play a role in tissue healing.
Comparative Study on the Syntheses and Properties of Three N‐lauroyl Aromatic Amino Acid Surfactants
Authors: Yang Jian , Zhou Yawen , Yang Bo , Huang Luyang , Liu Changyao , Han Fu , Xu Baocai
Published: April 2020

Three N‐lauroyl aromatic amino acid surfactants, namely, sodium N‐lauroyl phenylalaninate (SLP), sodium N‐lauroyl tyrosinate, and sodium N‐lauroyl tryptophanate (SLTr), with aromatic group structures were synthesized via methyl ester method. Mass spectrometry, Fourier transform infrared spectroscopy, and nuclear magnetic resonance were applied for the structural representation of products. A comparative study of the three surfactants in terms of surface, foam, and emulsifying properties and decontamination performance was conducted. Results demonstrated that aromatic structure significantly influenced the properties of the three surfactants. SLTr had the best surface performance and foam property, whereas SLP had the best emulsifying property. All three surfactants exhibited strong decontamination effects on protein‐soiled swatches.
Preparative separation of isoquinoline alkaloids from Corydalis impatiens using middle chromatogram isolated gel column coupled with positively charged reversed‐phase liquid chromatography
Authors: Wang Qi , Chen Wenjie , Wang Qilan , Tao Yanduo , Yu Ruitao , Pan Guoqing , Dang Jun
Published: April 2020

Positively charged reversed‐phase liquid chromatography was employed for the efficient preparative separation of isoquinoline alkaloids from Corydalis impatiens. Ten commercially available columns were compared for isoquinoline alkaloids analysis. While tailing, overloading, lower resolution, and buffer salts limited the application in purification of isoquinoline compounds of many of these columns, one positively charged reversed‐phase C18 column (XCharge C18) overcame these drawbacks, allowing for favorable separation resolution, even when loading isoquinoline compounds on a larger, preparative scale. The general separation process is as follows. First, isoquinoline alkaloids are enriched with Corydalis impatiens extract via a middle chromatogram isolated gel column. After column selection, separation is performed on an XCharge C18 analytical column, from which two evident chromatographic peaks are readily obtained. Finally, two isoquinoline alkaloids (protopine and corydamine) are selectively purified on the XCharge C18 preparative column. These results demonstrate that a middle chromatogram isolated gel column coupled with positively charged reversed‐phase liquid chromatography is effective for the preparative separation of isoquinoline alkaloids from Corydalis impatiens.
Palladium‐Catalyzed Polycondensation for the Synthesis of Poly(Aryl)Sulfides
Authors: Hou Peng , Oechsle Peter , Kuckling Dirk , Paradies Jan
Published: April 2020

The palladium‐catalyzed CS cross coupling reaction is investigated as a novel efficient tool for the synthesis of poly(phenyl)sulfide derivatives. The reaction proceeds through the polycondensation of dibromo arenes with a H2S‐surrogate to yield poly(aryl)sulfides. The reaction is generalized by the synthesis of so‐far‐unprecedented poly(2,5‐thiophene)sulfide. Number average molecular weights (Msss) of up to 3780 and 1770 g mol−1 for poly(phenyl)sulfide and poly(thiophene)sulfide are achieved with degrees of polymerization (DPn) of 10 and 7, respectively. A mechanism for the new polycondensation reaction is suggested.
Implementation and validation of ASL perfusion measurements for population imaging
Authors: Warnert Esther A. H. , Steketee Rebecca M. E. , Vernooij Meike W. , Ikram M. Arfan , Vogel Mika , Hernandez Tamames Juan‐Antonio , Kotek Gyula
Published: April 2020

Purpose

Pseudocontinuous arterial spin labeling (pCASL) allows for noninvasive measurement of regional cerebral blood flow (CBF), which has the potential to serve as biomarker for neurodegenerative and cardiovascular diseases. This work aimed to implement and validate pCASL on the dedicated MRI system within the population‐based Rotterdam Study, which was installed in 2005 and for which software and hardware configurations have remained fixed.

Methods

Imaging was performed on two 1.5T MRI systems (General Electric); (I) the Rotterdam Study system, and (II) a hospital‐based system with a product pCASL sequence. An in‐house implementation of pCASL was created on scanner I. A flow phantom and three healthy volunteers (<27 years) were scanned on both systems for validation purposes. The data of the first 30 participants (86 ± 4 years) of the Rotterdam Study undergoing pCASL scans on scanner I only were analyzed with and without partial volume correction for gray matter.

Results

The validation study showed a difference in blood flow velocity, sensitivity, and spatial coefficient of variation of the perfusion‐weighted signal between the two scanners, which was accounted for during post‐processing. Gray matter CBF for the Rotterdam Study participants was 52.4 ± 8.2 ml/100 g/min, uncorrected for partial volume effects of gray matter. In this elderly cohort, partial volume correction for gray matter had a variable effect on measured CBF in a range of cortical and sub‐cortical regions of interest.

Conclusion

Regional CBF measurements are now included to investigate novel biomarkers in the Rotterdam Study. This work highlights that when it is not feasible to purchase a novel ASL sequence, an in‐house implementation is valuable.
Rituximab in late‐onset myasthenia gravis is safe and effective
Authors: Sahai Supreet K. , Maghzi A. Hadi , Lewis Richard A.
Published: April 2020

Introduction

Late‐onset myasthenia gravis (LOMG; onset after 50 years of age) has different therapeutic decisionmaking challenges than MG in younger patients.

Methods

This is a retrospective series of seven patients with acetylcholine receptor antibody–positive MG, all treated with rituximab.

Results

The mean age of onset was 66 years. Three patients were nonresponders to previous therapy and six had developed side effects to prednisone. All patients were treated with at least one dose of rituximab. The MG Foundation of America Post‐Intervention Status ranged from MM‐0 to MM‐3 within a mean of 18.5 weeks. All patients were able to reduce or discontinue maintenance medications. No significant adverse events occurred.

Discussion

This series highlights the safety and efficacy of rituximab in LOMG. The presence of multiple comorbidities and the risks of other immunotherapy in older patients makes rituximab an attractive option. More experience is needed to clarify the use of rituximab for patients in this age group.
Audience success or art for art's sake? Efficiency evaluation of dance companies in the United States
Authors: del Barrio‐Tellado María José , Herrero‐Prieto Luis César , Murray Clare
Published: April 2020

Our aim is to evaluate the performance of American dance companies, considering that the production process may be subdivided into consecutive stages consisting of fundraising, artistic production, and social impact. A three‐stage network‐Data Envelopment Analysis model is applied which takes account of the links between stages in the form of intermediate inputs/outputs and provides an overall indicator of efficiency together with partial performance indicators in the stages. Given the lack of information for some variables, we previously undertook a process to impute missing values following MICE (multiple imputation by chained equations) procedures. Results show that the highest levels of efficiency are achieved during the cultural creation stage, whereas the lowest correspond to social impact, indicating that dance companies pursue artistic excellence in their cultural programming, irrespective of their activity's commercial outcomes. Moreover, public and private funds are seen to be channeled following this guideline, thereby justifying the non‐profit status of these entities.
A cross‐sectional study of distress: A cancer response
Authors: Ekman Hanna , Pettersson Alexandra , Jakobsson Liselotte , Garmy Pernilla
Published: April 2020

Aim

To describe the experience of distress in people with cancer of working age.

Design

A cross‐sectional study.

Methods

In this cross‐sectional study, patients (N = 168) with both ongoing (N = 56) and completed treatment (N = 105) completed the Distress Thermometer and the detailed problem list. Data were analysed by descriptive and analytical statistics.

Results

A large proportion of patients (29%) continued to experience high distress (>3 according to the Distress Thermometer) even after treatment was completed. Patients experienced several problems after treatment had ended such as fatigue (44%), sleep problems (34%), worries (31%), pain (31%), tingling in hands and feet (31%) and problems with memory/concentration (30%). Patients with financial/insurance problems had significantly higher distress than those who did not have these problems.
Data, Predictive Maintenance Promise Operational Benefits
Authors: Howley Andrew Chastain , Stillman Jeff
Published: April 2020

The water and wastewater industry is under growing pressure from expanding populations, aging infrastructure, falling revenues, and extreme weather events caused by climate change. Although new infrastructure will play a large role in positioning the industry for a more sustainable, resilient future, utilities now have the opportunity to harness and use data to improve the performance of existing assets, helping them achieve operational goals.
High‐Performance Methanal Sensor Based on Metal‐Organic Framework Based One‐Dimensional Photonic Crystal
Authors: Xing Yizhou , Shi Laixiang , Yan Jun , Chen Yunlin
Published: April 2020

One‐dimensional photonic crystal (1DPC) based on metal‐organic framework (MOF) ((MIL‐101‐NH2 (Cr) / TiO2)n )was prepared by a spin coating method. The 1DPC structure was built to detect vapor gas. The optical properties of the 1DPC were investigated by varying the number of period, incident angles and thickness of MOF, and the results of the experiment are agreed with theoretical simulation. The 1DPC gas sensor shows good selectivity for vapor gas and allows for a reliable distinction between methanal and other investigated analytes with the maximal peak shift (43 nm). It was found that the response time and recovery time for the sensor are around 500 ms and 20 s, respectively. The relationship between the peak shift position and the methanal concentration was demonstrated to be linear. Moreover, the fabricated 1DPC exhibited high repeatability and long‐term storage and thermal stability, which are beneficial for practical applications.
Revealing the Role of Aggregation and Surface Chemistry in the Bi‐phasic Anion Exchange Reactions of Cesium Lead Halide Perovskites
Authors: Sandeep K.
Published: April 2020

Tuning the emission of cesium lead halide perovskites by the post‐synthetic halogen exchange reactions is one of the easiest methods to obtain the opto‐electronic materials having emission in the entire visible region. Role of aggregation and the surface chemistry on the room temperature bi‐phasic anion exchange reactions of CsPbBr3 nanocrystal is investigated. Aggregation of the nanocrystals resulted in the decrease of surface bromide ions and CsPbBr3 became inactive towards the bi‐phasic anion exchange reactions. On the modification of the surface by enriching with bromide ions, aggregated CsPbBr3 nanocrystals became active towards anion exchange reaction. Surface halide ions have a significant role in the anion exchange reactions and the reaction starts at the surface and diffuses to the inner parts of the crystal as a result of its soft crystal nature. Understanding the role of surface chemistry on the anion exchange reactions, the potential of aggregated CsPbBr3 nanocrystals can be used for the opto‐electronic applications.
Retracted: 0D/3D Cu(II)‐containing coordination complexes constructed from the N,O‐donor ligands: structural insights and anticancer activity
Authors: Wang Jin‐Cai , Hu Peng , Zhao Rui‐Sheng , Li Hui‐Ling , Xu Zhi‐Chao , Guo Fei
Published: April 2020

Two novel coordination polymers based on Cu(II) ions as the metal nodes, {Cu(pydc)(2,2‐bpy)(DMF)}n (1, H2pydc=3,5‐pyridinedicarboxylate, 2,2‐bpy=2,2‐bipyridine) and {[Cu(H2O)2(H2imdc)2](H2O)}n (2, H3imdc=1H‐imidazole‐4,5‐dicarboxylic acid) have been synthesized via the hydrothermal or solvothermal conditions and characterized by techniques of elemental analysis, powder X‐ray diffraction (PXRD) as well as the analysis of single‐crystal X‐ray diffraction. Furthermore, the anti‐tumor activities of compounds 1 and 2 against on U251 brain glioma cells were evaluated in vitro. The Cell Counting Kit‐8 (CCK‐8) detection was performed to assess anti‐tumor activities of compounds 1 and 2 on U251 brain glioma cells. The Annexin V‐FITC/PI approach and Terminal deoxynucleotidyl transferase mediated dUTP nick‐end labeling (TUNEL) staining was used to determine the U251 brain glioma cells apoptosis after compounds treatment. Besides, the ROS assay was utilized to determine the ROS accumulation within U251 brain glioma cells after compounds treatment. The RT‐PCR was conducted to measure the ROS related genes relative expression.
FeCl3‐Mediated Friedel‐Crafts Alkylation and Oxidative Annulations: Facile Synthesis of Benzofurans
Authors: Zhang Xiongfei , Zeng Piaopiao , Zhang Shuo , Chen Zhiwei
Published: April 2020

An efficient method for the facile synthesis of benzofurans through FeCl3‐mediated intermolecular tandem reaction of anisole with glyoxal monohydrates was reported. This process provided the privileged structures of benzofurans in moderate to good yields under mild conditions. This reaction has many advantages, such as readily available starting materials, high atom economy and good functional group tolerance. This is firstly reported that FeCl3, acting as both a Lewis acid and an oxidant, was used for the synthesis of benzofuran.
A Selective and Reversible Fluorescent Probe for Zn2+ Detection in Living Cells
Authors: Chen Xin , Ma Yufan , Zhang Yuanyuan , Chen Qing , Wang Hongmei , Wang Zhuo
Published: April 2020

A newly 8‐aminoquioline based fluorescent probe (NQA) was designed and synthesized as a good turn‐on fluorescence sensor to reversibly detect Zn2+. The probe can detect Zn2+ in an aqueous solution with good selectivity without interference from other metal ions (Cd2+ in particular). And the limit of detection was calculated to be 2.15×10−9 M. The probe can efficiently monitor the change of concentration of Zn2+ in a broad pH range from 4.0 to 11.0. NQA can detection of Zn2+ reversibly based on the coordination interaction. NQA is biocompatibility and can be used to monitor the concentration of Zn2+ in living cells without the interference from other similar cations, especially Cd2+.
The Morphological and Capacitance Characteristics of A Novel Brush‐like Polymer Containing Polyaniline Segment
Authors: Wang Lin , Muslim Arzugul , Lan Haidie , Mamat Milangul
Published: April 2020

The brush‐like polymer composed of poly(acrylic acid)‐block‐grafted polyaniline (PAA42‐b‐PANI30‐g‐PANIm, marked as PAA42‐PANIx) with longer conjugate chain and good capacitance characteristics was synthesized through the combination of Reversible Addition‐Fragmentation Chain Transfer (RAFT) polymerization and free radical polymerization. The structure of the obtained product was characterized with 1H‐NMR and FT‐IR. Additionally, the morphology and particle size distribution of PAA42‐PANIx ultrasonically dispersed in ethanol was characterized with transmission electron microscopy. Through cyclic voltammetry (CV), chronopotentiometry and electrochemical impedance spectroscopy (EIS), the electrochemical properties of the product were analyzed. The results showed that PAA42‐b‐PANIx was a vesicle‐like particle with smaller size, uniform size and uniform morphology distribution, it has the mean particle size of only 38 nm. The final product had good peseudocapacitance, its specific capacitance reached to 1051.51 F⋅g−1 at the current density of 3 A⋅g−1.