bluuebunny/crossref_metadata_2025 huggingface dataset:
Midkine Interaction with Chondroitin Sulfate Model Synthetic Tetrasaccharides and Their Mimetics: The Role of Aromatic Interactions
Authors: García‐Jiménez María José , Gil‐Caballero Sergio , Maza Susana , Corzana Francisco , Juárez‐Vicente Francisco , Miles Jonathan R. , Sakamoto Kazuma , Kadomatsu Kenji , García‐Domínguez Mario , de Paz José L. , Nieto Pedro M.
Published: July 2021

Midkine (MK) is a neurotrophic factor that participates in the embryonic central nervous system (CNS) development and neural stem cell regulation, interacting with sulfated glycosaminoglycans (GAGs). Chondroitin sulfate (CS) is the natural ligand in the CNS. In this work, we describe the interactions between a library of synthetic models of CS‐types and mimics. We did a structural study of this library by NMR and MD (Molecular Dynamics), concluding that the basic shape is controlled by similar geometry of the glycosidic linkages. Their 3D structures are a helix with four residues per turn, almost linear. We have studied the tetrasaccharide‐midkine complexes by ligand observed NMR techniques and concluded that the shape of the ligands does not change upon binding. The ligand orientation into the complex is very variable. It is placed inside the central cavity of MK formed by the two structured beta‐sheets domains linked by an intrinsically disordered region (IDR). Docking analysis confirmed the participation of aromatics residues from MK completed with electrostatic interactions. Finally, we test the biological activity by increasing the MK expression using CS tetrasaccharides and their capacity in enhancing the growth stimulation effect of MK in NIH3T3 cells.
Bifunctional Polyene Cyclizations: Synthetic Studies on Pimarane Natural Products
Authors: Feilner Julian M. , Plangger Immanuel , Wurst Klaus , Magauer Thomas
Published: July 2021

Polyene cyclizations generate molecular complexity from a linear polyene in a single step. While methods to initiate these cyclizations have been continuously expanded and improved over the years, the majority of polyene substrates are still limited to simple alkyl‐substituted alkenes. In this study, we took advantage of the unique reactivity of higher‐functionalized bifunctional alkenes. The realization of a polyene tetracyclization of a dual nucleophilic aryl enol ether involving a transannular endo‐termination step enabled the total synthesis of the tricyclic diterpenoid pimara‐15‐en‐3α‐8α‐diol. The highly flexible and modular route allowed for the preparation of a diverse library of cyclization precursors specifically designed for the total synthesis of the tetracyclic nor‐diterpenoid norflickinflimiod C. The tetracyclization of three diversely substituted allenes enabled access to complex pentacyclic products and provided a detailed insight into the underlying reaction pathways.
Low‐Cost Membranen für die Vanadium‐Redox‐Flow‐Batterie
Authors: Düerkop Dennis , Widdecke Hartmut , Kunz Ulrich , Schilde Carsten , Schmiemann Achim
Published: July 2021

Gewebeverstärkte Protonenaustauschermembranen (gPEM) werden durch die Verarbeitung einer Polymersuspension bestehend aus gelöstem Polyethersulfon (PES) und dispersem Polystyrol (vernetzt, sulfonyliert und sulfoniert) mit Polymergeweben hergestellt und charakterisiert. Unter Verwendung eines Gewebes aus Polyetheretherketon (PEEK) mit einer Dicke von 128 µm weisen die hergestellten gPEM gegenüber Selemion CMVN und Nafion N115 eine höhere Protonenleitfähigkeit bei 25 °C auf. Die Energieeffizienz der bei 100 mA cm−2 getesteten Vanadium‐Redox‐Flow‐Zelle liegt mit Nafion N115 bei 68,6 %, mit CMVN bei 53,1 % und mit gPEM bei 69,4 %.
Integration of NRP1, RGS5, and FOXM1 expression, and tumour necrosis, as a postoperative prognostic classifier based on molecular subtypes of clear cell renal cell carcinoma
Authors: Yoshida Takashi , Ohe Chisato , Ikeda Junichi , Atsumi Naho , Saito Ryoichi , Taniguchi Hisanori , Ohsugi Haruyuki , Sugi Motohiko , Tsuta Koji , Matsuda Tadashi , Kinoshita Hidefumi
Published: July 2021

Molecular mechanisms of progression of clear cell renal cell carcinoma (ccRCC) have been proven with recent genomic or transcriptional analyses. However, it is still difficult to apply these analyses to daily clinical practice owing to economical and practical issues. Here, we established a pathology‐based, postoperative prognostic classification based on the well‐validated transcriptional classifier, ClearCode34, in ccRCC. A total of 342 cases with available tissue were identified and randomly allocated into a discovery cohort (n = 138) and a validation cohort (n = 204). Levels of mRNA were quantified using a nCounter Digital Analyzer, and the ccA/ccB subtypes were determined. Histological and immunohistochemistry (IHC) analyses were subsequently performed to establish a pathology‐based classification based on the mRNA levels. Finally, the prognostic ability of the new classifier was evaluated in both the discovery and validation cohorts. Of 138 cases in the discovery cohort, 78 (56.5%) and 60 (43.5%) were assigned to the ccA and ccB subtypes, respectively. Proangiogenic genes, neuropilin 1 (NRP1) and regulator of G protein signalling 5 (RGS5), were especially overexpressed in all ccRCC samples and were enriched in ccA‐assigned tumours. Histologically, tumour necrosis and the sarcomatoid feature were associated with the ccB subtype. In IHC analyses, expression of NRP1, RGS5, and forkhead box M1 (FOXM1), an epithelial–mesenchymal transition‐related factor, significantly correlated with the ccA/ccB subtypes. Combining these three IHC factors and tumour necrosis, we developed the IHC/histology‐based classifier, which showed good concordance with the ClearCode34 classifier with an accuracy of 0.80. The established classification significantly stratified relapse‐free, cancer‐specific, and overall survival rates in both the discovery and validation cohorts. The novel molecular pathology classifier integrating NRP1, RGS5, FOXM1, and tumour necrosis may enable the stratification of oncological outcomes for patients with ccRCC undergoing resection surgery.
Development of AC265347‐Inspired Calcium‐Sensing Receptor Ago‐Positive Allosteric Modulators
Authors: Dinh Le Vi , DeBono Aaron , Keller Andrew N. , Josephs Tracy M. , Gregory Karen J. , Leach Katie , Capuano Ben
Published: July 2021

The calcium‐sensing receptor (CaSR) is a clinical target in the treatment of hyperparathyroidism and related diseases. However, clinical use of approved CaSR‐targeting drugs such as cinacalcet is limited due to adverse side effects including hypocalcaemia, nausea and vomiting, and in some instances, a lack of efficacy. The CaSR agonist and positive allosteric modulator (ago‐PAM), AC265347, is chemically distinct from clinically‐approved CaSR PAMs. AC265347 potently suppressed parathyroid hormone (PTH) release in rats with a lower propensity to cause hypocalcaemia compared to cinacalcet and may therefore offer benefits over current CaSR PAMs. Here we report a structure activity relationship (SAR) study seeking to optimise AC265347 as a drug candidate and disclose the discovery of AC265347‐like compounds with diverse pharmacology and improved physicochemical and drug‐like properties.
N‐(Anilinoethyl)amide Melatonergic Ligands with Improved Water Solubility and Metabolic Stability
Authors: Ferlenghi Francesca , Mari Michele , Gobbi Gabriella , Elisi Gian Marco , Mor Marco , Rivara Silvia , Vacondio Federica , Bartolucci Silvia , Bedini Annalida , Fanini Fabiola , Spadoni Gilberto
Published: July 2021

The MT2‐selective melatonin receptor ligand UCM765 (N‐(2‐((3‐methoxyphenyl)(phenyl)amino)ethyl)acetamide), showed interesting sleep inducing, analgesic and anxiolytic properties in rodents, but suffers from low water solubility and modest metabolic stability. To overcome these limitations, different strategies were investigated, including modification of metabolically liable sites, introduction of hydrophilic substituents and design of more basic derivatives. Thermodynamic solubility, microsomal stability and lipophilicity of new compounds were experimentally evaluated, together with their MT1 and MT2 binding affinities. Introduction of a m‐hydroxymethyl substituent on the phenyl ring of UCM765 and replacement of the replacement of the N,N‐diphenyl‐amino scaffold with a N‐methyl‐N‐phenyl‐amino one led to highly soluble compounds with good microsomal stability and receptor binding affinity. Docking studies into the receptor crystal structure provided a rationale for their binding affinity. Pharmacokinetic characterization in rats highlighted higher plasma concentrations for the N‐methyl‐N‐phenyl‐amino derivative, consistent with its improved microsomal stability and makes this compound worthy of consideration for further pharmacological investigation.
A Versatile Ambient‐to‐High‐Pressure Reaction Transmission Cell for in situ/operando Infrared Spectroscopic Investigations
Authors: Weiß Jana , Rautenberg Christine , Rall Thomas , Kubis Christoph , Kondratenko Evgenii , Bentrup Ursula , Brückner Angelika
Published: July 2021

Design and applications of an in‐house developed high pressure/high temperature transmission FTIR reaction cell are presented. By coupling with a mass spectrometer online analysis of product formation is possible enabling operando FTIR spectroscopic studies. The cell, made of stainless‐steel, has been designed to be operable at pressures up to 30 bar and temperatures between 22 °C and 300 °C. Long‐time tests, with no signs of damage of the cell and windows have been conducted at 15 bar and 250 °C. The performance of the cell was tested by studying three types of CO2 hydrogenation reactions (CO2 Fischer‐Tropsch synthesis, CO2 methanation, CO2 conversion to dimethyl ether) on selected catalyst systems by varying temperature and pressure. The operando spectroscopic measurements revealed reliable data which reflect the same trends as found by respective catalytic tests.
A Versatile Ambient‐to‐High‐Pressure Reaction Transmission Cell for in situ/operando Infrared Spectroscopic Investigations
Authors: Weiß Jana , Rautenberg Christine , Rall Thomas , Kubis Christoph , Kondratenko Evgenii , Bentrup Ursula , Brückner Angelika
Published: July 2021

Invited for this month's cover is the group of Angelika Brücker at the Leibniz Institute for Catalysis in Rostock (Germany). The cover picture shows a self‐developed stainless‐steel reaction cell for operando transmission FTIR studies of heterogeneous catalytic gas‐phase reactions at pressures up to 30 bar and temperatures up to 300°C, which is connected to a mass spectrometer for online product analysis. The performance of the cell has been tested in three types of CO2 hydrogenation reactions (CO2 Fischer‐Tropsch synthesis, CO2 methanation, CO2 conversion to dimethyl ether) on various solid catalysts implemented as self‐supporting wafers. Catalytic data obtained with this cell showed the same trends as those measured in a fixed‐bed plug‐flow reactor, thus confirming their reliability. Read the full text of their Full Paper at 10.1002/cmtd.202100024.
Distress mediates the relationship between cognitive appraisal of medical care and benefit finding/posttraumatic growth in long‐term cancer survivors
Authors: Liu Zhunzhun , Doege Daniela , Thong Melissa S. Y. , Koch‐Gallenkamp Lena , Bertram Heike , Eberle Andrea , Holleczek Bernd , Nennecke Alice , Waldmann Annika , Zeißig Sylke Ruth , Pritzkuleit Ron , Arndt Volker
Published: July 2021

Background

The objective of this study was to ascertain long‐term cancer survivors' (LTCS') appraisal of medical care and how these perceptions may influence their health and well‐being, including benefit finding (BF) and posttraumatic growth (PTG).

Methods

In total, 6952 LTCS from a multiregional population‐based study in Germany completed the Benefit Finding Scale, the Posttraumatic Growth Inventory, the Questionnaire on Stress in Cancer, and self‐designed questions on cognitive appraisal of medical care. The authors explored the mediating role of distress between medical care appraisal and BF and PTG and the possible moderation of time since diagnosis in this relationship.

RESULTS

LTCS' medical care appraisals (“no unresolved/untreated symptoms,” “satisfaction with cancer care,” and “satisfaction with care for other diseases”) were positively associated with BF. PTG was positively associated with “no unresolved/untreated symptoms” and negatively associated with “satisfaction with care for other diseases.” Cancer distress partially mediated the associations between appraisals of medical care and BF, between “no unresolved/untreated symptoms” and PTG and between “satisfaction with care for other diseases” and PTG; whereas it totally mediated the association between “satisfaction with cancer care” and PTG. Time was a significant moderator in the model; the negative indirect effect of cognitive appraisal on BF and PTG through cancer distress weakened with longer time since diagnosis.

Conclusions

Cancer survivors' medical care appraisal is associated with their perceptions of BF and PTG through distress. Therefore, distress screening could be part of the regular workup to identify distressed cancer survivors who are not satisfied with medical care; these survivors may benefit from interventions to reduce distress and increase BF and PTG.
Exploring The Sequence of Electron Density Along The Chemical Reactions Between Carbonyl Oxides And Ammonia/Water Using Bond Evolution Theory
Authors: Adjieufack Abel Idrice , Bake Maraf Mbah , Nguimkeu Charnel Nguemo , Pilmé Julien , Ndassa Ibrahim Mbouombouo
Published: July 2021

The molecular mechanism of the reactions between four carbonyl oxides and ammonia/water are investigated using the M06‐2X functional together with 6‐311++G(d,p) basis set. The analysis of activation and reaction enthalpy shows that the exothermicity of each process increased with the substitution of electron donating substituents (methyl and ethenyl). Along each reaction pathway, two new chemical bonds C−N/C−O and O−H are expected to form. A detailed analysis of the flow of the electron density during their formation have been characterized from the perspective of bonding evolution theory (BET). For all reaction pathways, BET revealed that the process of C−N and O−H bond formation takes place within four structural stability domains (SSD), which can be summarized as follows: the depopulation of V(N) basin with the formation of first C−N bond (appearance of V(C,N) basin), cleavage of N−H bond with the creation of V(N) and V(H) monosynaptic basin, and finally the V(H,O) disynaptic basin related to O−H bond. On the other hand, in the case of water, the cleavage of O−H bond with the formation of V(O) and V(H) basins is the first stage, followed by the formation of the O−H bond as a second stage, and finally the creation of C−O bond.
Understanding the Molecular Origin of the Collective Movement in a Diarylethene‐based Photo‐Responsive Actuator
Authors: Amirjalayer Saeed
Published: July 2021

Remotely controlling macroscopic movement is one of the key elements to realize intelligent materials for applications ranging from sensing to robotics. Over the last few years, a number of photomechanical materials based on diarylethene derivatives have been developed. However, a detailed picture of the structural evolution within these soft actuators is often missing. In this work, an atomistic investigation uncovers how the photo‐induced molecular dynamics propagates to large‐scale motion and results in macroscopic deformation of the crystal. By correlating the intramolecular rearrangement within the photo‐responsive switching unit with the intermolecular packing, the molecular mechanism for the photomechanical phenomena is deciphered, which is fundamental for a rational development of photo‐responsive actuators.
Mechanochemical Process to Construct Porous Ionic Polymers by Menshutkin Reaction
Authors: Hou Shengtai , Meng Minshan , Liu Dandan , Zhang Pengfei
Published: July 2021

Abstract: The synthesis of porous ionic polymers (PIPs) via the Menshutkin reaction is intriguing because the reaction works smoothly in catalyst‐free condition with 100 % atom utilization. However, the rotation of methane site, nonrigid knots, and charge interaction all may cause collapses of the channel, which is detrimental to the synthesis PIP in solid‐state conditions. In this work, an inorganic salt (NaBr, NaCl: pollution‐free and easy to recycle) was rationally chosen as the hard template and effectively prevented the intermolecular packing. Moreover, the increased surface area dramatically promoted the catalytic activity of PIP for cyclic carbonate synthesis. This work provides a green and efficient strategy to construct PIPs via the Menshutkin reaction.
What is the effect of poaching activity on wildlife species?
Authors: Moore Jennifer F. , Uzabaho Eustrate , Musana Abel , Uwingeli Prosper , Hines James E. , Nichols James D.
Published: July 2021

Poaching is a pervasive threat to wildlife, yet quantifying the direct effect of poaching on wildlife is rarely possible because both wildlife and threat data are infrequently collected concurrently. In this study, we used poaching data collected through the Management Information System (MIST) and wildlife camera trap data collected by the Tropical Ecology Assessment and Monitoring (TEAM) network from 2014 to 2017 in Volcanoes National Park, Rwanda. We implemented co‐occurrence multi‐season occupancy models that accounted for imperfect detection to investigate the effect of poaching on initial occupancy, colonization, and extinction of five mammal species. Specifically, we focused on two species of conservation concern (mountain gorilla [Gorilla beringei beringei] and golden monkey [Cercopithecus mitis kandti]), and three species targeted by poachers (black‐fronted duiker [Cephalophus nigrifrons], bushbuck [Tragelaphus scriptus], and African buffalo [Syncerus caffer]). We found that the probability of local extinction was highest in sites with poaching activity for golden monkey and bushbuck. In addition, the probability of initial occupancy for golden monkey was highest in sites without poaching activity. We only found weak evidence of effects of poaching on parameters governing the occupancy dynamics of the other species. All species showed evidence of poaching presence affecting the probability of detection of the wildlife species. This is the first study to our knowledge to combine direct threat observations from ranger‐based monitoring data with camera trap wildlife observations to quantify the effect of poaching on wildlife. Given the widespread collection of ranger‐based monitoring and camera trap data, our approach is broadly applicable to numerous protected areas and has the potential to significantly improve conservation management. Specifically, the relationship between poaching activity and wildlife population dynamics can be combined with information on the relationship between ranger patrols and poaching activity to develop models useful for making wise decisions about ranger patrol deployment.
Mixed‐conifer forest reference conditions for privately owned timberland in the southern Cascade Range
Authors: Collins Brandon M. , Bernal Alexis , York Robert A. , Stevens Jens T. , Juska Andrew , Stephens Scott L.
Published: July 2021

The overwhelming majority of information on historical forest conditions in western North America comes from public lands, which may provide an incomplete description of historical landscapes. In this study we made use of an archive containing extensive timber survey data collected in the early 1920s from privately owned forestland. These data covered over 50,000 ha and effectively represent a 19% sample of the entire area. The historical forest conditions reconstructed from these data fit the classic model of frequent‐fire forests: large trees, low density, and pine‐dominated. However, unlike other large‐scale forest reconstructions, our study area exhibited relatively low overall variability in forest structure and composition across the historical landscape. Despite having low variability, our analyses revealed evidence of biophysical controls on tree density and pine fraction. Annual climatic variables most strongly explained the range in historical tree densities, whereas historical pine fraction was explained by a combination of topographic and climatic variables. Contemporary forest inventory data collected from both public and private lands within the same general area, albeit not a direct remeasurement, revealed substantial increases in tree density and greatly reduced pine fractions relative to historical conditions. Contemporary forests exhibited a far greater range in these conditions than what existed historically. These findings suggest that private forestland managed with multiaged silviculture may be similar to public forestland with respect to departure in forest structure and compositions from that of historical forests. However, there may be differences between management objectives that favor timber production, more typical on private lands, vs. those that favor restoration, increasingly supported on public lands.
Sex differences in morphology across an expanding range edge in the flightless ground beetle, Carabus hortensis
Authors: Yarwood Elisabeth , Drees Claudia , Niven Jeremy E. , Gawel Marisa , Schuett Wiebke
Published: July 2021

Species’ ranges are dynamic, changing through range shifts, contractions, and expansions. Individuals at the edge of a species’ shifting range often possess morphological traits that increase movement capacity, that are not observed in individuals farther back within the species’ range. Although morphological traits that increase in proportion toward the range edge may differ between the sexes, such sex differences are rarely studied.

Here, we test the hypotheses that body size and condition increase with proximity to an expanding range edge in the flightless ground beetle, Carabus hortensis, and that these trait changes differ between the sexes.

Male, but not female, body size increased with proximity to the range edge. Body size was positively correlated with male front and mid tibia length and to female hind tibia length, indicating that body size is indicative of movement capacity in both sexes. Body condition (relative to body size) decreased with increasing population density in males but not females. Population density was lowest at the range edge.

Our results indicate that sex is an important factor influencing patterns in trait distribution across species’ ranges, and future studies should investigate changes in morphological traits across expanding range margins separately for males and females. We discuss the implications for sex differences in resource allocation and reproductive rates for trait differentiation across species’ shifting ranges.
Short‐term impact of fire on the total soil microbial and nitrifier communities in a wet savanna
Authors: Srikanthasamy Tharaniya , Barot Sébastien , Koffi Fulgence K. , Tambosco Kevin , Marcangeli Yoan , Carmignac David , N'Dri Aya Brigitte , Gervaix Jonathan , Le Roux Xavier , Lata Jean‐Christophe
Published: July 2021

Savannas are characterized by the coexistence of grasses and trees. Fires are critical for their coexistence, because they decrease the survival of tree seedlings and saplings and their recruitment to the adult stage. In some humid savannas, perennial grasses inhibit nitrification and trees stimulate nitrification, which likely favors coexistence between trees and grasses. However, fires may influence plant capacity to control nitrogen cycling, which could subsequently influence tree–grass coexistence and savanna nitrogen budget. Therefore, we sampled soil in a humid savanna of Ivory Coast under the dominant nitrification‐inhibiting grass species and the dominant nitrification‐stimulating tree species and under bare soil before and after (i.e., 5 days) fire during the long dry season. We quantified the total microbial and nitrifier abundances and transcriptional activities and the nitrification enzyme activity. Fire decreased soil water content, probably by increasing evaporation and, maybe, by triggering the growth of grasses, and increased soil ammonium availability likely due to ash deposition and increased mineralization. Fire did not impact the total archaeal, bacterial, or fungal abundances, or that of the nitrifiers. Fire did not impact archaeal transcriptional activity and increased bacterial and fungal total transcriptional activities. In contrast, fire decreased the archaeal nitrifier transcriptional activities and the nitrification enzymatic activity, likely due to the often reported resumption of the growth of nitrification‐inhibiting grasses quickly after the fire (and the subsequent increase in root exudation). These results pave the way for a better understanding of the short‐term effects of fire on nitrogen cycling and tree–grass competition for nitrogen.
Excluding spatial sampling bias does not eliminate oversplitting in DNA‐based species delimitation analyses
Authors: Lukic Daniel , Eberle Jonas , Thormann Jana , Holzschuh Carolus , Ahrens Dirk
Published: July 2021

DNA barcoding and DNA‐based species delimitation are major tools in DNA taxonomy. Sampling has been a central debate in this context, because the geographical composition of samples affects the accuracy and performance of DNA barcoding. Performance of complex DNA‐based species delimitation is to be tested under simpler conditions in absence of geographic sampling bias. Here, we present an empirical dataset sampled from a single locality in a Southeast‐Asian biodiversity hotspot (Laos: Phou Pan mountain). We investigate the performance of various species delimitation approaches on a megadiverse assemblage of herbivorous chafer beetles (Coleoptera: Scarabaeidae) to infer whether species delimitation suffers in the same way from exaggerate infraspecific variation despite the lack of geographic genetic variation that led to inconsistencies between entities from DNA‐based and morphology‐based species inference in previous studies. For this purpose, a 658 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) was analyzed for a total of 186 individuals of 56 morphospecies. Tree‐based and distance‐based species delimitation methods were used. All approaches showed a rather limited match ratio (max. 77%) with morphospecies. Poisson tree process (PTP) and statistical parsimony network analysis (TCS) prevailingly over‐splitted morphospecies, while 3% clustering and Automatic Barcode Gap Discovery (ABGD) also lumped several species into one entity. ABGD revealed the highest congruence between molecular operational taxonomic units (MOTUs) and morphospecies. Disagreements between morphospecies and MOTUs have to be explained by historically acquired geographic genetic differentiation, incomplete lineage sorting, and hybridization. The study once again highlights how important morphology still is in order to correctly interpret the results of molecular species delimitation.
Essential requirement for polypyrimidine tract binding proteins 1 and 3 in the maturation and maintenance of mature B cells in mice
Authors: Monzón‐Casanova Elisa , Bates Kirsty J. , Smith Christopher W. J. , Turner Martin
Published: July 2021

The maturation of immature B cells and the survival of mature B cells is stringently controlled to maintain a diverse repertoire of antibody specificities while avoiding self‐reactivity. At the molecular level this is regulated by signaling from membrane Ig and the BAFF‐receptor that sustain a pro‐survival program of gene expression. Whether and how posttranscriptional mechanisms contribute to B cell maturation and survival remains poorly understood. Here, we show that the polypyrimidine tract binding proteins (PTBP) PTBP1 and PTBP3 bind to a large and overlapping set of transcripts in B cells. Both PTBP1 and PTBP3 bind to introns and exons where they are predicted to regulate alternative splicing. Moreover, they also show high‐density of binding to 3’ untranslated regions suggesting they influence the transcriptome in diverse ways. We show that PTBP1 and PTBP3 are required in B cells beyond the immature cell stage to sustain transitional B cells and the B1, marginal zone and follicular B cell lineages. Therefore, PTBP1 and PTBP3 promote the maturation of quiescent B cells by regulating gene expression at the posttranscriptional level.
Amperometric Sarcosine Biosensors Based on Electrodeposited Conductive Films Contain Indole‐6‐carboxylic Acid
Authors: Zhang Xiaofang , Chen Jing , Wang Qia , Du Bing , Fan Gaochao , Zheng Weidong , Yang Haipeng , Xu Tailin
Published: July 2021

Sarcosine level in serum is of important clinical significance in distinguishing prostate cancer. This work depicts an amperometric sarcosine biosensor with good anti‐interference performance by electro‐codepositing manganese phosphate, 3,4‐ethylenedioxythiophene (EDOT) and indole‐6‐carboxylic acid (IA) on the glass carbon electrode. The prepared sarcosine biosensor has a wide linear detection range (1–55 μM) with a low detection limit of 0.11 μM. This work provides an anti‐interference approach by controlling the surface charge density of the biosensor to sarcosine sensing, which has great potential to be used as point of care testing (POCT) device for the rapid detection of prostate cancer biomarkers.
Sheath‐assisted versus sheathless dielectrophoretic particle separation
Authors: Dalili Arash , Hoorfar Mina
Published: July 2021

Lab‐on‐chip devices are widely being used for binary and ternary cell/particle separation applications. Among the lab‐on‐chip methods, dielectrophoresis (DEP) is a cost‐effective and label‐free method, with great capabilities for size‐based separation of cells and particles, which is mostly performed in sheath‐assisted forms. However, the elimination of the sheath flows offers advantages such as ease of operation and higher sample throughput. In this work, we present a comparison of sheath‐assisted and sheathless DEP separation of three sizes of microparticles using tilted electrodes. The sheath‐assisted design was capable of separating the 5, 10, and 15 μm particles with a separation efficiency as high as 98.0% for 15 μm particles. By adding a DEP focusing region, a sheathless DEP separator was proposed, which offered higher throughputs (up to 10 times) at the cost of lowering the separation efficiency (a reduction up to 10.3% for 15 μm) compared to the sheath‐assisted design. To enhance the separation efficiency, a combination of the DEP focusing accompanied by weak sheath flows from both sides was proposed. This design achieved the highest sample separation yield in the outlets (as high as 98.7% for 15 μm) with a sample throughput of more than 4.2 μL/min. This study provides insights into the choice of an appropriate platform for any application in which the yield, purity, throughput, and portability must be considered.
Patterned vascularization in a directional ice‐templated scaffold of decellularized matrix
Authors: Shen Li , Song Xiuyue , Xu Yalan , Tian Runhua , Wang Yin , Li Peifeng , Li Jing , Bai Hao , Zhu Hai , Wang Dong
Published: July 2021

Vascularization is fundamental for large‐scale tissue engineering. Most of the current vascularization strategies including microfluidics and three‐dimensional (3D) printing aim to precisely fabricate microchannels for individual microvessels. However, few studies have examined the remodeling capacity of the microvessels in the engineered constructs, which is important for transplantation in vivo. Here we present a method for patterning microvessels in a directional ice‐templated scaffold of decellularized porcine kidney extracellular matrix. The aligned microchannels made by directional ice templating allowed for fast and efficient cell seeding. The pure decellularized matrix without any fixatives or cross‐linkers maximized the potential of tissue remodeling. Dramatical microvascular remodeling happened in the scaffold in 2 weeks, from small primary microvessel segments to long patterned microvessels. The majority of the microvessels were aligned in parallel and interconnected with each other to form a network. This method is compatible with other engineering techniques, such as microfluidics and 3D printing, and multiple cell types can be co‐cultured to make complex vascularized tissue and organ models.
Experimental investigation on the application of carbon dioxide adsorption for a shale reservoir
Authors: Zhang Hongyan , Khayatnezhad Majid , Davarpanah Afshin
Published: July 2021

New advancements in unconventional oil reservoirs to enhance cumulative oil production are essential for petroleum industries to develop new oilfields. Carbon dioxide injection (CO2) is considered one of the most functional enhanced oil recovery (EOR) methods, especially in shale reservoirs, regarding their low permeability of pores and cracks. This paper aims to experimentally investigate the crucial factors such as shale particle size, pressure, and temperature on the CO2 adsorption that can be used as a useful guideline for developing unconventional hydrocarbon reservoirs. Thereby, pressure increase would be an essential parameter to increase CO2 storage capacity; however, temperature increase has a reverse pattern and has caused to decrease the CO2 storage capacity. The essence of the oil recovery factor from shale reservoirs is another crucial factor that depends on the pressure, temperature, and soaking time factors. CO2 injection would be a proper (EOR) method to increase the oil recovery factor for higher pressures and temperatures. Therefore, the applicability of CO2 injection in shale reservoirs could provide efficient results rather than other EOR techniques.
Founder and professionalCEOs' performance differences across institutions: Ameta‐analyticstudy
Authors: Zaandam Aten , Hasija Dinesh , Ellstrand Alan E. , Cummings Michael E.
Published: July 2021

Research Summary

We examine the effect of institutions on performance differences between founder and professional CEOs. We do so by integrating an institutional perspective with findings from the literatures on CEOs' managerial discretion and cognition. Specifically, we theorize that in informal institutional environments characterized by high power distance and individualism and in formal institutional contexts characterized by low regulatory and political quality, differences in cognitive styles lead founders to enjoy performance advantages over professional CEOs. The results of our meta‐analysis of 117 studies across 22 countries conducted between 1987 and 2020 support our predictions. We conclude by discussing the implications for research and policy regarding institutional development and the governance of entrepreneurial firms.

Managerial Summary

We develop a framework to examine the influence of the institutional environment on performance differences between founder and professional CEOs. Our results show that founder CEOs experience performance advantages across high discretionary institutional settings when compared with professional CEOs. Boards may use this information to guide their recommendations or decisions related to founder CEO succession or retention. Moreover, firms pursuing international strategies such as joint ventures may also use this information as one of their search criteria while shortlisting their potential prospect partners.
The paradoxical effect of responsible leadership on employee cyberloafing: A moderated mediation model
Authors: Zhu Jinqiang , Wei Hongguo , Li Hai , Osburn Holly
Published: July 2021

Drawing on the conservation of resources theory (COR), this study examines the relationship between responsible leadership and counterproductive work behavior of employee cyberloafing. Incorporating related concepts of felt obligation, job stress, and conscientiousness as possible mediators and moderators between responsible leadership and cyberloafing, a field study and a quasi‐experimental design were conducted on two data sets. Data from Study 1 showed that while responsible leadership reduced employee cyberloafing through increased felt obligation, it also promoted employee cyberloafing through increasing job stress. Study 2 further showed that conscientiousness moderated the mediating effect of felt obligation between responsible leadership and cyberloafing. The results from this work illustrate the paradoxical mechanisms of self‐regulatory resources anticipated from COR.
Piezotronics in two‐dimensional materials
Authors: Zhang Qin , Zuo Shanling , Chen Ping , Pan Caofeng
Published: July 2021

The fascinating two‐dimensional (2D) materials are being potentially applied in various fields from science to engineering benefitting from the charming physical and chemical properties on optics, electronics, and magnetism, compared with the bulk crystal, while piezotronics is a universal and pervasive phenomenon in the materials with broking center symmetry, promoting the new field and notable achievements of piezotronics in 2D materials with higher accuracy and sensitivity. For example, 20 parts per billion of the detecting limitations in NO2 sensor, 500 μm of spatial strain resolution in flexible devices, and 0.363 eV output voltage in nanogenerators. In this review, three categories of 2D piezotronics materials are first introduced ranging from organic to inorganic data, among which six types of 2D inorganic materials are emphasized based on the geometrical arrangement of different atoms. Then, the microscopic mechanism of carrier transport and separation in 2D piezotronic materials is highlighted, accompanied with the presentation of four measured methods. Subsequently, the developed applications of 2D piezotronics are discussed comprehensively including different kinds of sensors, piezo‐catalysis, nanogenerators and information storage. Ultimately, we suggest the challenges and provide the ideas for qualitative–quantitative research of microscopic mechanism and large‐scale integrated applications of 2D piezotronics.

image
Promoting the emergence of tacting three‐digit numerals through a chain prompt combined with matrix training
Authors: Clements Andrea , Fisher Wayne W. , Keevy Madeleine
Published: July 2021

Children with autism spectrum disorder (ASD) have difficulty generalizing from directly trained responses to untrained responses (i.e., emergent responding). In this study, we used a chain prompt combined with matrix training to teach 2 participants with ASD to tact 192 three‐digit numerals. We used a multiple‐baseline design across matrices to evaluate the treatment effects on trained and untrained tacts of numerals. Both participants mastered all numerals exposed to training and all numerals not exposed to training after 3 to 5 sixteen‐trial sessions per matrix. One participant learned to tact 8 numerals for each 1 numeral exposed to direct training, and the other participant learned to tact 12 numerals for each 1 numeral exposed to direct training. We discuss these results relative to the effectiveness and efficiency of our chain prompt combined with matrix training for teaching tacting skills for targets with shared stimulus properties that facilitate generalization to untrained targets.
Differential Iron Requirements for Osteoblast and Adipocyte Differentiation
Authors: Edwards Daniel F. , Miller Christopher J. , Quintana‐Martinez Arelis , Wright Christian S. , Prideaux Matthew , Atkins Gerald J. , Thompson William R. , Clinkenbeard Erica L.
Published: July 2021

Bone marrow mesenchymal progenitor cells are precursors for various cell types including osteoblasts, adipocytes, and chondrocytes. The external environment and signals act to direct the pathway of differentiation. Importantly, situations such as aging and chronic kidney disease display alterations in the balance of osteoblast and adipocyte differentiation, adversely affecting bone integrity. Iron deficiency, which can often occur during aging and chronic kidney disease, is associated with reduced bone density. The purpose of this study was to assess the effects of iron deficiency on the capacity of progenitor cell differentiation pathways. Mouse and human progenitor cells, differentiated under standard osteoblast and adipocyte protocols in the presence of the iron chelator deferoxamine (DFO), were used. Under osteogenic conditions, 5μM DFO significantly impaired expression of critical osteoblast genes, including osteocalcin, type 1 collagen, and dentin matrix protein 1. This led to a reduction in alkaline phosphatase activity and impaired mineralization. Despite prolonged exposure to chronic iron deficiency, cells retained viability as well as normal hypoxic responses with significant increases in transferrin receptor and protein accumulation of hypoxia inducible factor 1α. Similar concentrations of DFO were used when cells were maintained in adipogenic conditions. In contrast to osteoblast differentiation, DFO modestly suppressed adipocyte gene expression of peroxisome‐proliferating activated receptor gamma, lipoprotein lipase, and adiponectin at earlier time points with normalization at later stages. Lipid accumulation was also similar in all conditions. These data suggest the critical importance of iron in osteoblast differentiation, and as long as the external stimuli are present, iron deficiency does not impede adipogenesis. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
The Co(OH)2@Glu‐TSC nanoflakes enhance the apoptosis in hepatoma G2 cell
Authors: Shahrokhshahi Asal , Salehzadeh Ali , Vaziri Hamid Reza , Moradi‐Shoeili Zeinab
Published: July 2021

The aim of the present study was to evaluate the impact of cobalt hydroxide nanoparticles conjugated with glutamic acid and thiosemicarbazides (Co(OH)2@Glu‐TSC) on Hepatoma G2 (HpG2) cancer cell lines. The effect of different concentrations of Co(OH)2@Glu‐TSC nanoparticles on the growth of Human Embryonic Kidney‐293 (HEK‐293) normal cells and HpG2 cancer cells was evaluated. The half maximal inhibitory concentration of Co(OH)2@Glu‐TSC nanoparticle on HEK‐293 and HepG2 was 701.65 μg/ml and 133.62 μg/ml, respectively. The percentage of HpG2 living cells in untreated group was significantly higher than that in Co(OH)2@Glu‐TSC‐treated group (95.5 vs. 59.5%; p < .001). Dot plots of Annexin V/PI staining showed a 15.3% early‐stage apoptosis and a 15.3% late‐stage apoptosis in Co(OH)2@Glu‐TSC‐treated cells. Untreated cancer cells exhibited 2.83% early‐stage apoptosis and a 0.23% late‐stage apoptosis. Intracellular Reactive Oxygen Species in Co(OH)2@Glu‐TSC‐treated cells (2,342) was significantly higher than that in untreated cells (2,342 vs. 707; p < .001). The mean expression of Caspase 3, maternally expressed gene 3, and P53 genes were significantly higher in Co(OH)2@Glu‐TSC‐treated cancer cells compared to untreated cancer cells. Co(OH)2@Glu‐TSC nanoparticle has a high cytotoxic effect on cancer cells which is possibly mediated by the induction of overproduction of reactive oxygen species, oxidative stress, and overexpression of apoptotic genes.
miR‐92a promotes cervical cancer cell proliferation, invasion, and migration by directly targeting PIK3R1
Authors: Wang Yijun , Chen Aner , Zheng Chenyang , Zhao Lingjun
Published: July 2021

Objective

To clarify the role of miR‐92a in regulating the malignant progression of cervical cancer and its specific molecular mechanism.

Methods

qRT‐PCR was used to detect the differential expression of miR‐92a in cervical cancer and adjacent tissues. The effects of overexpression of miR‐92a on the proliferation, migration, and invasion of HeLa and SiHa cells were tested. Luciferase assays and rescue experiments were used to investigate the regulatory mechanism of miR‐92a on its downstream gene PIK3R1 and their interaction in the progression of cervical cancer.

Results

miR‐92a was significantly up‐regulated in cervical cancer tissues. Overexpression of miR‐92a significantly increased the ability of cervical cancer cells to proliferate, migrate, and invade. PIK3R1 was identified as a downstream gene of miR‐92a. In cervical cancer tissues, PIK3R1 was found to be down‐regulated and negatively correlated with the level of miR‐92a. Overexpression of PIK3R1 reversed the promotional effect of overexpressed miR‐92a on the proliferation, migration, and invasion of cervical cancer.

Conclusion

miR‐92a is up‐regulated in cervical cancer tissues. miR‐92a promotes the malignant development of cervical cancer by negatively regulating PIK3R1.
Resolution of serologic problems due to cold agglutinin mediated autoimmune hemolytic anemia and its transfusion decision
Authors: Ying Qiming , Lv Dingfeng , Fu Xiaomei , Shi Shuanglu , Chen Luyan , He Yiwen , Yang Jing , Yang Shujun , Mu Qitian
Published: July 2021

Background

Autoimmune hemolytic anemia (AIHA) is a rare disease characterized by hemolysis caused by autoantibodies against erythrocyte surface antigen. These antibodies can be classified as warm, cold, or mixed types.

Methods

We report two cases of cold agglutinin disease (CAD), which were eventually diagnosed owing to blood group discrepancy. Resolution was achieved after washing the red blood cells (RBCs) with warm saline and absorbing the autoantibodies at 4°C with the washed RBCs. We also assessed the patient's condition and discussed the strategy of blood transfusion.

Results

The first case occurred after postoperative chemotherapy for rectal cancer, and the other manifested with anemia from the outset. Direct antiglobulin tests were positive and revealed autoantibodies against C3d only. Cold agglutinin titration was performed, and the titers of both were 1:1024. Eventually, the patient's condition stabilized without blood transfusion.

Conclusion

The serological discrepancies observed in the blood transfusion department can successfully guide blood transfusion decisions in cases of CAD.
Immunohistochemical detection of hepatocyte nuclear factor‐4α in vertebrates
Authors: Jiang Shuying , Tanaka Toshiya , Yagami Ren , Hasegawa Go , Umezu Hajime , Fujiyoshi Yukio , Kodama Tatsuhiko , Naito Makoto , Ajioka Yoichi
Published: July 2021

Hepatocyte nuclear factor‐4α (HNF4α) presents in multiple isoforms generated using alternative promoter (P1 and P2) and splicing. Neither conservation of tissue distribution of HNF4α isoforms, nor presence of alternative promoter usage is known. In this study, to detect the expression of HNF4α in some species of animals, we have applied monoclonal antibodies against P1 (K9218) and P2 (H6939) promoter‐driven and P1/P2 promoter‐driven H1415 HNF4α for immunohistochemistry and western blot analysis. Antibody K9218 was observed in the hepatocytes, proximal tubules of the kidney, and epithelial cells in the mucosa of the small intestine and colon of rats, chicken, and tortoise, whereas antibody H6939 signal were detected in the stomach, pancreas, bile duct, and pancreatic duct of human and rats. The signal for antibody K9218 was recognized in tissues of a wide range of mammals, bird, reptile, amphibian, and fish as well. Antibody H1415 displayed a positive reaction in hepatocytes and intestinal epithelial cells in chicken and tortoise, whereas the bile duct, mucosal epithelial cells in the stomach, or pancreas in these animals were negative. Western blotting showed the binding of the antibody with HNF4α protein from each animal. The sequence of human HNF4α was 100% identical to murine and rat HNF4α, 88.9% to chicken, 77.8% to Xenopus HNF4α, and 81.5% to medaka. However, the specific part of human and invertebrate Drosophila HNF4 shares only 14.8% sequence identity. This antibody is useful for detecting HNF4α isoforms in a wide range of vertebrates, and suggests many insights into animal evolution.