bluuebunny/crossref_metadata_2025 huggingface dataset:
Unveiling the Role of Active Oxygen Species in Oxidative Dehydrogenation of Ethane with CO2 over NiFe/CeO2
Authors: Guo Man , Feng Kai , Wang Yaning , Yan Binhang
Published: April 2021

The oxidative dehydrogenation of ethane (ODH) assisted by CO2 to produce ethylene is inevitably accompanied by the side reaction of dry reforming (DRE) to produce carbon monoxide. However, the key factor determining the dehydrogenation selectivity is still ambiguous. In this paper, four different NiFe/CeO2 catalysts were synthesized via an impregnation method over four types of CeO2. The dehydrogenation selectivity of the four catalysts ranged from 40 % to 83 %. Temperature‐programmed surface reaction and transient response experiments reveal the existence of two types of oxygen species over NiFe/CeO2 catalysts. FeOx layers exist as an oxygen species supply buffer over CeO2 supports. Weakly electrophilic oxygen species supplied by FeOx overlayers could participate in producing C2H4 while strong electrophilic oxygen species supplied by CeO2 supports could participate in producing CO. The content of weakly electrophilic oxygen species is identified to be a rational descriptor of C2H4 selectivity.
High‐Quality Thin Films of UiO‐66‐NH2 by Coordination Modulated Layer‐by‐Layer Liquid Phase Epitaxy
Authors: Semrau A. Lisa , Fischer Roland A.
Published: April 2021

We report the fabrication of macroscopically and microscopically homogeneous, crack‐free metal‐organic framework (MOF) UiO‐66‐NH2 (UiO: Universitetet i Oslo; [Zr6O4(OH)4(bdc‐NH2)6]; bdc‐NH22−: 2‐amino‐1,4‐benzene dicarboxylate) thin films on silicon oxide surfaces. A DMF‐free, low‐temperature coordination modulated (CM), layer‐by‐layer liquid phase epitaxy (LPE) using the controlled secondary building block approach (CSA). Efficient substrate activation was determined as a key factor to obtain dense and smooth coatings by comparing UiO‐66‐NH2 thin films grown on ozone and piranha acid‐activated substrates. Films of 2.60 μm thickness with a minimal surface roughness of 2 nm and a high sorption capacity of 3.53 mmol g−1 MeOH (at 25 °C) were typically obtained in an 80‐cycle experiment at mild conditions (70 °C, ambient pressure).
Self‐Foaming Metal‐Organic Gels Based on Phytic Acid and Their Mechanical, Moldable, and Load‐Bearing Properties.
Authors: Xiao Yali , Gong Xi , Zhang Jianyong
Published: April 2021

A catalogue of metal‐organic gels are synthesized from phytic acid (PA) and a diversity of metal ions (Fe3+, Cr3+, Al3+, Ce3+, Y3+, Co2+, Ni2+, Mn2+, Cu2+, Zn2+, Mg2+) upon heating at 80 °C. PA−M gels have various morphologies, including irregular granular (PA−Fe, PA−Al, PA−Ce, PA−Cr, PA−Ni, PA−Co), spongy (PA−Y), and hollow tremella‐like (PA−Cu) morphologies. Interestingly for PA−Fe‐1 : 4 (PA:Fe3+=1 : 4) a large amount of gas is generated during the gelation process leading to a self‐foaming gel. The PA−Fe‐1 : 4 self‐foaming gel shows reversible gel‐sol phase transition. The gel is unusually weakened and transformed into a sol at room temperature, and the sol is reversed to gelation when heated again at 80 °C. PA−Fe‐1 : 4 gel also shows shapeable and load‐bearing properties, and it can bear up to 200 times of its weight, depending on the gas amount fixed in the foam gel and the aging time. This work provides a catalogue of self‐foaming supramolecular gels with tunable properties based on naturally abundant resources.
The Unusual Photochromic and Hydrochromic Switching Behavior of Cellulose‐Embedded 1,8‐Naphthalimide‐Viologen Derivatives in the Solid‐State
Authors: Sun Zhimin , Ni Yanhai , Prakasam Thirumurugan , Liu Wenqi , Wu Huang , Zhang Zhao , Di Haiting , Baldridge Kim K. , Trabolsi Ali , Olson Mark A.
Published: April 2021

Stimuli‐responsive chromic materials such as photochromics, hydrochromics, thermochromics, and electrochromics have a long history of capturing the attention of scientists due to their potential industrial applications and novelty in popular culture. However, hybrid chromic materials that combine two or more stimuli‐triggered color changing properties are not so well known. Herein, we report a design strategy that has led to a series of emissive 1,8‐naphthalimide‐viologen dyads which exhibit unusual dual photochromic and hydrochromic switching behavior in the solid‐state when embedded in a cellulose matrix. This behavior manifests as reversible solid state fluorescence hydrochromism upon changes in atmospheric relative humidity (RH), and reversible solid state photochromism upon generation of a cellulose‐stabilized viologen radical cation. In this design strategy, the bipyridinium unit serves as both a water‐sensitive receptor for the hydrochromic fluorophore‐receptor system, and a photochromic group, capable of eliciting its own visible colorimetric response, generating a fluorescence quenching radical cation with prolonged exposure to ultraviolet (UV) light. These dyes can be inkjet‐printed onto cellulose paper or drop‐cast as cellulose powder‐based films and can be unidirectionally cycled between three different states which can be characteristically visualized under UV light or visible light. The material's photochromism, hydrochromism, and underlying mechanism of action was investigated using computational analysis, dynamic vapor sorption/desorption isotherms, electron paramagnetic resonance spectroscopy, and variable humidity UV‐Vis adsorption and fluorescence spectroscopies.
Rhodium‐Catalyzed Enantioselective Synthesis of Highly Fluorescent and CPL‐Active Dispiroindeno[2,1‐c]fluorenes
Authors: Cadart Timothée , Nečas David , Kaiser Reinhard P. , Favereau Ludovic , Císařová Ivana , Gyepes Róbert , Hodačová Jana , Kalíková Květa , Bednárová Lucie , Crassous Jeanne , Kotora Martin
Published: April 2021

The enantioselective synthesis of chiral [7]‐helical dispirodihydro[2,1‐c]indenofluorenes (DSF‐IFs) was achieved for the first time in good yields with high er values (er up to 99 : 1). The crucial step of the whole reaction sequence was the enantioselective intramolecular [2+2+2] cycloaddition of tethered triynediols to indenofluorenediols, which was catalyzed by a Rh/SEGPHOS® complex. Further transformations led to the corresponding DSF‐IFs. The prepared helically chiral DSF‐IFs combine circularly polarized luminescence (CPL) activity (glum=∼10−3) with exceptionally high fluorescence quantum yields (up to Φlum=0.97).
The proof of the pudding is in the bleaching … oder so ähnlich
Authors: Emden Markus , Hild Pitt , Murer Livia
Published: April 2021

Anliegen der in loser Folge erscheinenden Versuche ist es, Impulse für chemische Versuche zu geben, die gefahrlos zu Hause mit haushaltsüblichen Gegenständen durchgeführt werden können. Sie können damit als Quelle für das gemeinsame Ausprobieren mit Kindern zuhause dienen, in Kindergärten oder an Schulen sowie zur Verwendung bei Tagen der offenen Tür. Ein Stückweit sind sie zu verstehen als Antwort auf den oft gehörten Satz: „Ach, Du bist Chemiker/in? Dann mach doch mal eben ein Experiment.“
Gradient of vernalization requirement in carrot cultivars from diverse geographical origins
Authors: Wohlfeiler Josefina , Alessandro María Soledad , Cavagnaro Pablo Federico , Galmarini Claudio Rómulo
Published: April 2021

On the basis of their vernalization requirement (VR) for flowering, a genetically conditioned trait, carrots (Daucus carota L.) are typically classified as annuals and biennials. A previous study using F2 populations derived from crosses among carrots from different geographical origins revealed a model of two genes and three alleles controlling VR, with dominance of annuality for both genes. The present work evaluated VR in carrot cultivars from diverse origins, including those used in a previous study. We induced vernalization during different periods of cold exposure (20, 30, 40, 60, and 90 d) and different temperatures (∼5 and ∼15 °C). Increased flowering rates and earlier onset of flowering were associated with longer and more intense cold exposures. In most cultivars, 60–90 d at 5 °C (but not at 15 °C) were enough for vernalizing a large proportion of the plants. In general, biennials required longer cold exposure than annuals to flower, although variation within annuals and biennials was also found, suggesting a gradient of VR in the carrot germplasm, which reinforces our previously proposed genetic model. The plant materials used in this work cover the broadest range of VR in carrot reported to date. These findings contribute to carrot breeding and production, helping to choose the specific genotype and appropriate sowing time in different environments either for root or seed production.
Perivascular macrophages create an intravascular niche for CD8+ T cell localisation prior to the onset of fatal experimental cerebral malaria
Authors: Qin Jim , Lovelace Michael D , Mitchell Andrew J , de Koning‐Ward Tania , Grau Georges ER , Pai Saparna
Published: April 2021

Objectives

The immunologic events that build up to the fatal neurological stage of experimental cerebral malaria (ECM) are incompletely understood. Here, we dissect immune cell behaviour occurring in the central nervous system (CNS) when Plasmodium berghei ANKA (PbA)‐infected mice show only minor clinical signs.

Methods

A 2‐photon intravital microscopy (2P‐IVM) brain imaging model was used to study the spatiotemporal context of early immunological events in situ during ECM.

Results

Early in the disease course, antigen‐specific CD8+ T cells came in contact and arrested on the endothelium of post‐capillary venules. CD8+ T cells typically adhered adjacent to, or were in the near vicinity of, perivascular macrophages (PVMs) that line post‐capillary venules. Closer examination revealed that CD8+ T cells crawled along the inner vessel wall towards PVMs that lay on the abluminal side of large post‐capillary venules. ‘Activity hotspots’ in large post‐capillary venules were characterised by T‐cell localisation, activated morphology and clustering of PVM, increased abutting of post‐capillary venules by PVM and augmented monocyte accumulation. In the later stages of infection, when mice exhibited neurological signs, intravascular CD8+ T cells increased in number and changed their behaviour, actively crawling along the endothelium and displaying frequent, short‐term interactions with the inner vessel wall at hotspots.

Conclusion

Our study suggests an active interaction between PVM and CD8+ T cells occurs across the blood–brain barrier (BBB) in early ECM, which may be the initiating event in the inflammatory cascade leading to BBB alteration and neuropathology.
Identifying changing interspecific associations along gradients at multiple scales using wavelet correlation networks
Authors: Ding Zhangqi , Ma Keming
Published: April 2021

Identifying interspecific associations is very important for understanding the community assembly process. However, most methods provide only an average association and assume that the association strength does not vary along the environmental gradient or with time. The scale effects are generally ignored. We integrated the idea of wavelet and network topological analysis to provide a novel way to detect nonrandom species associations across scales and along gradients using continuous or presence–absence ecological data. We first used a simulated species distribution data set to illustrate how the wavelet correlation analysis builds an association matrix and demonstrates its statistical robustness. Then, we applied the wavelet correlation network to a presence–absence data set of soil invertebrates. We found that the associations of invertebrates varied along an altitudinal gradient. We conclude by discussing several possible extensions of this method, such as predicting community assembly, utility in the temporal dimension, and the shifting effects of highly connected species within a community. The combination of the multiscale decomposition of wavelet and network topology analysis has great potential for fostering an understanding of the assembly and succession of communities, as well as predicting their responses to future climate change across spatial or temporal scales.
Plasticity in response to plant–plant interactions and water availability
Authors: Wang Shu , Callaway Ragan M.
Published: April 2021

The plastic responses of plants to abiotic and biotic environmental factors have generally been addressed separately; thus we have a poor understanding of how these factors interact. For example, little is known about the effects of plant–plant interactions on the plasticity of plants in response to water availability. Furthermore, few studies have compared the effects of intra‐ and interspecific interactions on plastic responses to abiotic factors. To explore the effects of intraspecific and interspecific plant–plant interactions on plant responses to water availability, we grew Leucanthemum vulgare and Potentilla recta with a conspecific or the other species, and grew pairs of each species as controls in pots with the roots, but not shoots, physically separated. We subjected these competitive arrangements to mesic and dry conditions, and then measured shoot mass, root mass, total mass and root : shoot ratio and calculated plasticity in these traits. The total biomass of both species was highly suppressed by both intra‐ and interspecific interactions in mesic soil conditions. However, in drier soil, intraspecific interactions for both species and the effect of P. recta on L. vulgare were facilitative. For plasticity in response to water supply, when adjusted for total biomass, drought increased shoot mass, and decreased root mass and root : shoot ratios for both species in intraspecific interactions. When grown alone, there were no plastic responses in any trait except total mass, for either species. Our results suggested that plants interacting with other plants often show improved tolerance for drought than those grown alone, perhaps because of neighbor‐induced shifts in plasticity in biomass allocation. Facilitative effects might also be promoted by plasticity to drought in root : shoot ratios.
Ir−Sn Tetrazole Complexes with Proton‐Responsive P−OH Groups and an Ir−Ir Tetrazole Complex for CO2 Hydrogenation
Authors: Ocansey Edward , Darkwa James , Makhubela Banothile C. E.
Published: April 2021

Bimetallic catalytic systems, especially heterogeneous bimetallic catalytic systems, have been shown to be effective catalysts for CO2 hydrogenation as a result of synergistic effects. Here‐in we report the synthesis of bimetallic Ir−Ir, Ir−Sn and a novel five‐membered heteroatomic Ir−Sn tetrazole complex. These complexes were obtained as a result of the heterolysis of P−S bond in the ligands during complexation. These complexes were evaluated for catalytic activity in homogeneous CO2 hydrogenation where they displayed excellent catalytic activity generating formate selectively. The mechanism of action for the Ir−Sn catalysts for CO2 hydrogenation indicates metal−metal bond breakage prior to formation of catalytically active species. However, this metal−metal bond breakage did not result in the decomposition of the catalysts. In addition, these bimetallic complexes were observed to effectively hydrogenate CO2 directly, or hydrogenate bicarbonate ions formed in solution during the catalytic cycle. For Ir−Ir catalyst, only one metal center was found to be directly involved in CO2 hydrogenation with the second iridium center primarily responsible as an electron source
Biomass derived hierarchically porous carbon inherent structure as an effective metal free cathode for Li‐O2/air battery
Authors: Arjunan Ariharan , Subbiah Maheswari , Sekar Mahendran , VS. Ajay Piriya , Balasubramanian Viswanathan , Sundara Ramaprabhu
Published: April 2021

A hierarchical porous carbon framework derived from betel‐nut is synthesized and employed as a bifunctional cathode in a Li‐O2/air battery. The prepared betel nut derived activated porous carbon (BNAPC) material exhibits an ordered and merged tube‐like porous morphology and a high specific surface area of 768 m2/g. The presence of both meso and micro porous leads to a well‐developed 3D interconnected carbon framework, which provides an efficient path for the diffusion of the reactant (oxygen as well as air) and also allows stocking the discharge product of Li2O2. Therefore, it exhibits a high specific capacity and excellent rate performance. A maximum discharge capacity of 9560 and 2000 mAh/g at a current density of 100 mA/g for oxygen and ambient air respectively as the reactant is achieved. The prepared material also exhibits reversible cyclic stability of 27 cycles with a specific capacity of 1000 mAh/g at a 100 mA/g current density in oxygen atmosphere.
pH‐driven entrapment of enrofloxacin in casein‐based nanoparticles for the enhancement of oral bioavailability
Authors: Yuan Zhi‐xiang , Deng Shichen , Chen Li , Hu You , Gu Jian , He Lili
Published: April 2021

Enrofloxacin (ENR), a broad‐spectrum antibacterial drug, has extremely poor water solubility contributing to low bioavailability, which prevents drug formulation design and limits its wide application in livestock farming and aquaculture. Compared to conventional formulations of ENR, casein (Cas)‐based drug delivery system has been reported to have significant advantages in the improvement of solubility and bioavailability of drugs. In this paper, we report the preparation process of ENR‐loaded Cas nanoparticles (ENR‐Cas) using magnetic agitation without any organic agent and the optimization of the formulation. Transmission electron microscopy (TEM), dynamic light scattering (DLS), differential scanning calorimetry (DSC), powder X‐ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) were all adopted to characterize the ENR‐Cas. Results showed that the obtained ENR‐Cas were approximately spherical with a particle size of 171.6 ± 13.8 nm with a polydispersity index of 0.322 ± 0.053. In vitro release behavior of ENR‐Cas showed a sustained release profile. Additionally, in vivo study in rats displayed that the mean plasma concentration of ENR after oral administration of ENR‐Cas was significantly higher than that treated with ENR suspension. The mean residence time (MRT0–24) of ENR was enhanced by Cas nanoparticles from 9.287 ± 0.524 to 11.372 ± 1.139 hr in comparison with ENR suspension. Accordingly, the area under the curve (AUC0–24) of ENR‐Cas was 80.521 ± 6.624 μg·hr/ml, 3.8‐fold higher than that of ENR suspension (20.850 ± 1.715 μg·hr/ml). Therefore, it can be concluded that ENR‐Cas enhanced the absorption, prolonged the retention time, and improved oral bioavailability of ENR. Taken the good oral safety of Cas into consideration, ENR‐Cas should be a more promising oral preparation of ENR for clinical application.
Sedimentology of the Baluti Formation (Late Triassic) in the Warte area, northeastern Iraqi Kurdistan region
Authors: Asaad Irfan Sh. , Balaky Sardar M. , Hasan Goran F. , Aswad Mahdi Kh.
Published: April 2021

A detailed sedimentological investigation of the Baluti Formation (Late Triassic) in the Warte section, Imbricated Zone, northeastern Kurdistan region of Iraq has been undertaken for the first time. The formation is comprised of 34 m of dolomitic limestone, marly limestone, and marly dolomitic limestone which is partially brecciated and all interbedded with shale and several beds of marl in the lower part. Based on the field observations and petrographic inspections, four different lithostratigraphic units were identified in the studied section, which are, in ascending order: marly dolomitic limestone interbedded with marl and shale unit, brecciated marly dolomitic limestone interbedded with shale unit, fractured marly dolomitic limestone unit, and marly limestone interbedded with shale unit. The petrographic study of 19 thin sections of Baluti carbonates shows that the majority are composed of carbonate mud (micrite). The skeletal grains include ostracods, calcispheres, benthonic foraminifera, gastropods, bivalves, clasts, and bioclasts. While non‐skeletal grains include peloids, intraclasts, and extraclasts. The results of X‐ray diffraction (XRD) of five samples and scanning electron microscope (SEM) of three samples of the shale and marl of the studied formation show that the main clay mineral is illite, whereas non‐clay mineral is dolomite. The carbonate rocks of the Baluti Formation were subjected to different diagenetic processes, such as micritization, dolomitization, cementation, compaction, solution, pyritization, neomorphism, and fracturing. Three main microfacies were identified in the Baluti carbonates and according to their environmental interpretation, they are grouped into one basic type of facies association—subtidal‐semi restricted lagoon. Field observation, petrographic, microfacies, and textural analysis indicate that the Baluti Formation in the Warte section was deposited in a shallow marine, subtidal (lagoon) environment with semi‐restricted conditions.
Group‐2 Innate Lymphoid Cells Promote HCC Progression Through CXCL2‐Neutrophil‐Induced Immunosuppression
Authors: Xu Xingyuan , Ye Longyun , Zhang Qi , Shen Hang , Li Shanshan , Zhang Xiaoyu , Ye Mao , Liang Tingbo
Published: April 2021

Background and Aims

Due to their inherent characteristics, the function of group‐2 innate lymphoid cells (ILC2s) varies in a context‐dependent manner. ILC2s are involved in certain liver diseases; however, their involvement in HCC is unknown. In the present study, we assessed the role of an HCC‐derived ILC2 population in tumor progression.

Approach and Results

Through FACS and single‐cell RNA sequencing, we discovered that ILC2s were highly enriched in human HCC and correlated significantly with tumor recurrence and worse progression‐free survival as well as overall survival in patients. Mass cytometry identified a subset of HCC‐derived ILC2s that had lost the expression of killer cell lectin‐like receptor subfamily G, member 1 (KLRG1). Distinct from their circulating counterparts, these hepatic ILC2s highly expressed CD69 and an array of tissue resident–related genes. Furthermore, reduction of E‐cadherin in tumor cells caused the loss of KLRG1 expression in ILC2s, leading to their increased proliferation and subsequent accumulation in HCC sites. The KLRG1− ILC2 subset showed elevated production of chemotaxis factors, including C‐X‐C motif chemokine (C‐X‐C motif) ligand (CXCL)‐2 and CXCL8, which in turn recruited neutrophils to form an immunosuppressive microenvironment, leading to tumor progression. Accordingly, restoring KLRG1 in ILC2s, inhibiting CXCL2 in ILC2s, or depleting neutrophils inhibited tumor progression in a murine HCC model.

Conclusions

We identified HCC‐associated ILC2s as an immune regulatory cell type that promotes tumor development, suggesting that targeting these ILC2s might lead to new treatments for HCC.
Evidence and politics of patient experience in Ontario: The perspective of healthcare providers and administrators
Authors: Zakkar Moutasem A. , Meyer Samantha B. , Janes Craig R.
Published: April 2021

Background

Patient experience has a direct impact on patients' engagement in healthcare, their commitment to treatment plans, and their relationship with their healthcare providers, all of which can impact their health outcomes. The complexity of the healthcare system, the increasing health needs of the population, and the priority and knowledge differences among healthcare stakeholders impact how they conceptualize and seek to achieve the ideal patient experience and the weights that they give to different elements of this experience.

Aims

This study sought to understand the perspectives of healthcare providers and administrators in Ontario regarding the factors affecting the patient experience.

Materials & Methods

Qualitative data were collected between April 2018 and May 2019. Twenty‐one semi‐structured interviews were conducted. Interviewees included physicians, nurses, optometrists, dietitians, quality managers, and policymakers. Thematic analysis was used to analyse the data, utilizing and extending a previously developed patient experience framework.

Results

Several themes emerged in the data, and they represent two perspectives on patient experience: the biomedical perspective, which prioritizes health outcomes and gives high weights to healthcare experience factors that can be controlled by healthcare providers, while ignoring other factors, and the sociopolitical perspective, which recognizes the impacts of healthcare politics and the social context of health on patient experience in Ontario.

Conclusion

The study is timely in light of the current changes in the Ontario healthcare system and the healthcare reform started by the new government, as it sheds light on the possible negative impact of healthcare policy and politics on patient experience.
Preservation of female fertility: The current therapeutic strategy
Authors: Henry Laurie , Labied Soraya , Jouan Caroline , Nisolle Michelle
Published: April 2021

Background

Preservation of female fertility is a relatively new field in medicine that has grown very rapidly in recent decades. At the beginning, embryo freezing remained the most effective technique. Thereafter, cryopreservation of oocytes and ovarian tissue was considered a secure tool in human fertility preservation. Storage of cortical ovarian tissue is moreover relevant for children, prepubertal girls, and adult patients who cannot benefit from cryopreservation of oocytes.

Objective

To analyze and review recent and relevant scientific literature on medical and social reasons for preservation of fertility.

Methods

The review was conducted based on articles identified from PubMed databases using keywords.

Main results

Oocyte vitrification allows women to preserve their fertility without the need for fertilization. Nowadays, thousands of healthy children have been born from this procedure. Occurrence of pregnancy depends on two main factors: the number of mature oocytes in storage and the age of the patient at the time of vitrification. Numerous adaptations have been developed to suit the ovarian stimulation regiments to patients with cancer. In young prepubertal girls, freezing of ovarian tissue remains the best and only option.

Conclusion

Oocyte vitrification therefore appears to be the gold standard technique of preserving fertility in young women.
Tumor suppressor role of hsa_circ_0035445 in gastric cancer
Authors: Sun Weiliang , Zhang Haiyan , Duan Wenbiao , Zhu Hui , Gu Chijiang
Published: April 2021

Circular RNAs (circRNAs) are closely related to the occurrence and development of cancers. However, the roles of circRNAs in gastric cancer are largely unknown. Total 104 pairs of gastric cancer tissues and non‐cancer tissues, fasting plasma of 42 healthy people and 42 gastric cancer patients’ one day before operation and 10 days after operation were collected. Quantitative reverse transcription‐polymerase chain reaction was used to detect the expression level of hsa_circ_0035445. The receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were used to analyze its diagnostic value. Small interfering RNA and overexpression vector were used to downregulate and upregulate the expression of hsa_circ_0035445, respectively. Cell Counting Kit‐8 and colony formation assays were used to detect the proliferation ability. Trans‐well assay and scratch assay were used to detect the migration ability. Finally, flow cytometry was used to detect the changes of cell cycle distribution and apoptosis. Hsa_circ_0035445 was lowly expressed in gastric cancer tissues, plasma of gastric cancer patients, and gastric cancer cells. The expression level of hsa_circ_0035445 in gastric cancer tissues was relationship with tumor size and distant metastasis. The AUC of hsa_circ_0035445 in tissues and plasma was 0.68 and 0.86, respectively. Upregulation of hsa_circ_0035445 suppressed the proliferation and migration, promoted apoptosis, and blocked cells at G0/G1 phase. Downregulation of hsa_circ_0035445 promoted the proliferation and migration, suppressed apoptosis, and blocked cells at S phase. In conclusion, hsa_circ_0035445 may become a new target for the treatment of gastric cancer.
Gait mechanics of a blind echolocating rodent: Implications for the locomotion of small arboreal mammals and proto‐bats
Authors: Granatosky Michael C. , Amanat Sonia , Panyutina Aleksandra A. , Youlatos Dionisios
Published: April 2021

Arboreal mammals have evolved a range of biomechanical adaptations that allow them to navigate trees effectively. One such feature that has received considerable attention is the importance of vision that helps arboreal animals assess gap distances, assure proper foot placement, and inspect potential risks. While there is considerable debate about the relative importance of the visual system specifics, there is little doubt that the ability to at least see the environment must confer some level of safety when navigating arboreal substrates. In this study, we explore spatiotemporal and kinematic patterns of arboreal locomotion in the Vietnamese pygmy dormouse (Typhlomys chapensis), a blind rodent that uses ultrasonic echolocation to navigate in tree canopies. We compare these data with five other species of arboreal rodents and primates. Spatiotemporal gait characteristics are largely similar between the Vietnamese pygmy dormouse and other small‐bodied arboreal species analyzed. Most notable is the tendency for relatively high‐speed asymmetrical gaits on large‐diameter substrates and slower symmetrical lateral‐sequence gaits on small‐diameter substrates. Furthermore, for all species speed is primarily regulated by increasing stride frequency rather than length. Kinematics of the Vietnamese pygmy dormouse changed little in response substrate size and were primarily driven by speed. These findings suggest that the information gathered during ultrasonic scanning is sufficient to allow effective quadrupedal locomotion while moving on arboreal supports. The Vietnamese pygmy dormouse may serve as a model for the quadrupedal nocturnal ancestor of bats, which had started developing ultrasonic echolocation and reducing vision while likely occupying an arboreal niche.
The effect of variable temperature, humidity, and substrate wettability on Gecko (Gekko gecko) locomotor performance and behavior
Authors: Ringenwald Bridget E. , Bogacki Erin C. , Narvaez Carla A. , Stark Alyssa Y.
Published: April 2021

Adhesive and locomotor performances of geckos are inherently linked by specialized morphological and biomechanical features. As such, we predict that conditions that lead to poor adhesive performance (i.e., low resistance to applied force while clinging) also lead to poor locomotor performance and behavior (i.e., slowed running speed, increased frequency and duration of stops, more failed or incomplete runs). In this study, we test the prediction that running speed changes as a function of adhesive performance in variable temperature (12 and 32°C), humidity (30, 55, 70, 80% relative humidity), and substrate wettability (hydrophilic glass, intermediately wetting plexiglass). We also expect other locomotor performance traits and behaviors, such as stopping and avoiding treatment conditions, to change as a function of adhesive performance. The results of this study do not fully support our prediction: gecko locomotor performance does not change as a function of humidity or substrate wettability, unlike adhesive performance. As an anticipated result of ectothermy, geckos run significantly slower and stop more frequently and longer at 12°C than 32°C. At high temperature, geckos required significantly more running attempts on hydrophilic glass than plexiglass to complete the experimental procedure, suggesting that this treatment condition is unfavorable. The results of this study highlight the robust locomotive response of geckos to variation in adhesive performance and environmental conditions, and have significant implications for predictions about habitat use and behavior in their natural environment.
Risk of postpartum hemorrhage in multiparous women with Gaucher disease: A call for reconsidering enzyme replacement therapy in all pregnant patients
Authors: Cohen Yael , Frydman Dafna , Rotem Reut , Kofman Roei , Zimran Ari , Revel‐Vilk Shoshana , Grisaru‐Granovsky Sorina
Published: April 2021

For the last three decades, enzyme replacement therapy (ERT) for Gaucher disease (GD) has been available. We aimed to evaluate the effect of ERT on the pregnancy and obstetric outcome in a unique group of multiparous women with type 1 GD (GD1) who had pregnancies with and without ERT. The Gaucher Unit database (1987‐2019) was searched for multiparous women who had pregnancies before and after the institution of ERT. Data were collected from the clinic files and study‐specific questionnaires. Descriptive, correlation analysis and generalized estimating equations (GEE) were used to study the effect of ERT and confounding variables on study outcomes. We identified 19 women with 105 pregnancies, among which 26 (24.7%) terminated in first‐trimester miscarriage. The risk for miscarriage was associated with the severity of GD1 genotype and phenotype, but not with ERT usage. Early postpartum hemorrhage (PPH) was reported in 16 (84%) women after 25 deliveries (31.6%, 95% CI 21.6%‐43.1%). The risks of early PPH and red blood cell (RBC) transfusions were significantly lower when ERT was used during pregnancy, OR (95% CI) 0.13 (0.03‐0.54) and 0.27 (0.08‐0.94), respectively, compared to pregnancies without the use of ERT. Enzyme replacement therapy during pregnancy is risk reducing for early PPH and RBC transfusions in women with GD1. We suggest considering ERT for the benefit of all pregnant women with GD1, including mild GD1.
High‐yield synthesis of a tau PET radioligand and its nonradioactive ligand using an alternative protection and deprotection strategy
Authors: Kim Hyunjung , Choe Yearn Seong
Published: April 2021

Recently developed tau imaging radiopharmaceuticals show specific uptake in tau protein‐rich regions in human brains without off‐target binding. These radiopharmaceuticals and their nonradioactive reference ligands are generally obtained in low (radio)chemical yields. In the present study, we investigated high‐yield synthesis of 18F‐RO948 ([18F]1) and its nonradioactive ligand (1). The ligand 1 was synthesized by a Suzuki‐Miyaura coupling reaction between 9‐(4‐methoxybenzyl)‐9H‐pyrrolo[2,3‐b:4,5‐c′]dipyridin‐2‐yl trifluoromethanesulfonate (3) and 2‐fluoro‐5‐(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)pyridine (4), followed by oxidative removal of the para‐methoxybenzyl (PMB) group with ceric ammonium nitrate (CAN). This two‐step reaction gave 1 in 55.8% yield. The precursor for [18F]1 was synthesized from 3 and 2‐nitro‐5‐(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)pyridine (6). The resulting PMB‐protected precursor 8 was obtained in 74.5% yield. [18F]1 was synthesized by radiofluorination of 8 (radiochemical conversion (RCC): 95.7 ± 1.7%), followed by deprotection of the PMB group with CAN. This one‐pot, two‐step radiochemical synthesis followed by HPLC purification gave [18F]1 in high decay‐corrected radiochemical yield (54‐60%). The RCC of [18F]fluoride to [18F]1 in our two‐step synthesis method was similar to that in a one‐step radiofluorination reaction of a tert‐butoxycarbonyl (BOC)‐protected precursor 10 that proceeds with concomitant thermal deprotection of the BOC group. Taken together, the results of this study suggest that this high‐yield synthesis method is useful for the synthesis of 18F‐labeled (NH)heteroarene compounds.
Preclinical evaluation of [11C]L‐235 as a radioligand for Positron Emission Tomography cathepsin K imaging in bone
Authors: Bennacef Idriss , Rubins Daniel , Riffel Kerry , Williams Mangay , Posavec Diane J. , Holahan Marie A. , Purcell Mona L. , Haley Hyking D. , Wolf Mary , Stachel Shawn J. , Lubbers Laura S. , Wesolowski Gregg A. , Duong Le T. , Hamill Terence G. , Evelhoch Jeffrey L. , Hostetler Eric D.
Published: April 2021

The cathepsin K (CatK) enzyme is abundantly expressed in osteoclasts, and CatK inhibitors have been developed for the treatment of osteoporosis. In our effort to support discovery and clinical evaluations of a CatK inhibitor, we sought to discover a radioligand to determine target engagement of the enzyme by therapeutic candidates using positron emission tomography (PET). L‐235, a potent and selective CatK inhibitor, was labeled with carbon‐11. PET imaging studies recording baseline distribution of [11C]L‐235, and chase and blocking studies using the selective CatK inhibitor MK‐0674 were performed in juvenile and adult nonhuman primates (NHP) and ovariectomized rabbits. Retention of the PET tracer in regions expected to be osteoclast‐rich compared with osteoclast‐poor regions was examined. Increased retention of the radioligand was observed in osteoclast‐rich regions of juvenile rabbits and NHP but not in the adult monkey or adult ovariectomized rabbit. Target engagement of CatK was observed in blocking studies with MK‐0674, and the radioligand retention was shown to be sensitive to the level of MK‐0674 exposure. [11C]L‐235 can assess target engagement of CatK in bone only in juvenile animals. [11C]L‐235 may be a useful tool for guiding the discovery of CatK inhibitors.
Immunolocalization of epidermal differentiation complex proteins reveals distinct molecular compositions of cells that control structure and mechanical properties of avian skin appendages
Authors: Alibardi Lorenzo , Eckhart Leopold
Published: April 2021

The epidermal differentiation complex (EDC) is a cluster of genes that encode structural proteins of skin derivatives with variable mechanical performances, from the scales of reptiles and birds to the hard claws and beaks, and to the flexible but resistant corneous material of feathers. Corneous proteins with or without extended beta‐regions are produced from avian genomes, and include the largely prevalent corneous beta proteins (CβPs, formerly indicated as beta‐keratins), and minor contribution from histidine‐rich proteins, trichohyalin‐like proteins (scaffoldin), loricrin, and other proteins rich in cysteine or other types of amino acids. The light‐microscopic and ultrastructural immunolocalization of major and minor EDC‐proteins in avian skin (feather CβPs, EDKM, EDWM, EDMTFH, EDDM, and scaffoldin) suggests that each specific appendage consists of a particular mix of these proteins in addition to the main proteins containing a peculiar beta‐region of 34 amino acids, indicated as feather/scale/claw/beak CβPs (fCβPs, sCβPs, cCβPs, bCβPs). This indicates that numerous proteins of the EDC are added to the variable meshwork of intermediate filament keratins to produce avian epidermis with different mechanical and functional properties. Although the specific roles for these proteins are not known they likely make an important contribution to the final material properties of the different skin appendages of birds. The highest number of sauropsid CβPs is found in birds, suggesting a relation to the evolution of feathers, and additional epidermal differentiation proteins have contributed to the evolutionary adaptations of avian skin.
Hypoalbuminemia in patients following their recovery from severe coronavirus disease 2019
Authors: Ali Kameran M. , Ali Ayad M. , Tawfeeq Hassan M. , Figueredo Grazziela P. , Rostam Hassan M.
Published: April 2021

Coronavirus disease 2019 (COVID‐19) is caused by a contagious virus that has spread to more than 200 countries, territories, and regions. Thousands of studies to date have examined all aspects of this disease, yet little is known about the postrecovery status of patients, especially in the long term. Here, we examined erythrocyte sedimentation rate (ESR), C‐reactive protein (CRP), and serum albumin biomarkers in patients with a history of severe and mild‐to‐moderate COVID‐19 following their recovery. In patients with severe COVID‐19 serum albumin had a strong negative correlation with both ESR and CRP levels (R2 = − 0.861 and R2 = − 0.711), respectively. Also, there was a positive correlation between ESR and CRP level (R2 = 0.85) in the same group. However, there was no correlation between these biomarkers among mild‐to‐moderate COVID‐19 patients. In addition, no correlation was recorded between the severe and mild‐to‐moderate COVID‐19 groups. This finding highlights the sustained elevation of ESR and CRP level and reduced serum albumin level that may persist postrecovery in patients with a history of severe COVID‐19.
Optimized lesion size index (o‐LSI): A novel predictor for sufficient ablation of pulmonary vein isolation
Authors: Matsuura Gen , Kishihara Jun , Fukaya Hidehira , Oikawa Jun , Ishizue Naruya , Saito Daiki , Sato Tetsuro , Arakawa Yuki , Kobayashi Shuhei , Shirakawa Yuki , Nishinarita Ryo , Horiguchi Ai , Niwano Shinichi , Ako Junya
Published: April 2021

Background

Although the lesion size index (LSI) has been well established, it is sometimes difficult to achieve first‐pass pulmonary vein isolation (PVI) and to avoid acute pulmonary vein reconnections, even with LSI‐guided procedures. The purpose of this study was to assess the predictive accuracy of a novel parameter, the optimized lesion size index (o‐LSI), to perform PVI.

Methods

The voltage maps created by the Advisor™ high‐density (HD) grid catheter before PVI in 35 atrial fibrillation (AF) patients were examined for an association between the voltage amplitude and insufficient ablation sites (IAS), which were defined as either (i) spontaneous reconnection sites, (ii) dormant PV conduction sites unmasked with 20 mg of adenosine triphosphate disodium hydrate (ATP) injection, or (iii) PV‐LA gap sites after the initial PVI.

Results

IAS was observed in 25/1417 of the total ablation sites. IAS was significantly associated with higher bipolar voltage areas (4.20 ± 2.68 vs 2.43 ± 1.93 mV, P < .0001) but not with LSI. A novel index, o‐LSI (defined as LSI/bipolar voltage), was significantly lower in IAS than in others (1.14 [0.82, 1.81] vs 2.35 [1.31, 4.80] LSI/mV). By receiver operating characteristic analysis, an o‐LSI of 2.04 was the best cutoff value for the prediction of IAS (88% sensitivity and 55% specificity, P < .0001, areas under the curve: 0.742).

Conclusion

Low o‐LSI was strongly associated with IAS, potentially providing a novel index to improve first‐pass PV isolation.
A wavelet transform method to determine monsoon onset and retreat from precipitation time‐series
Authors: García‐Franco Jorge L. , Osprey Scott , Gray Lesley J.
Published: April 2021

A new method to determine monsoon onset and retreat timings using wavelet transform methodology applied to precipitation time‐series at the pentad scale is described. The principal advantage of this method is its portability, since it can be easily adapted for any region and dataset. The application of the method is illustrated for the North American Monsoon and the Indian Monsoon using four different precipitation datasets and climate model output. The method is shown to be robust across all the datasets and both monsoon regions. The mean onset and retreat dates agree well with previous methods. Spatial distributions of the precipitation and circulation anomalies identified around the onset and retreat dates are also consistent with previous work and illustrate that this method may be used at the grid‐box scale, not just over large area‐averaged regions. The method is also used to characterize the strength and timing of the Midsummer drought (MSD) in southern Mexico and Central America. A two peak structure is found to be a robust structure in only in 33% of the years, with other years showing only one peak or no signs of a bimodal distribution. The two‐peak structure analysed at the grid‐box scale is shown to be a significant signal in several regions of Central America and southern Mexico. The methodology is also applied to climate model output from the Met Office Hadley Centre UKESM1 and HadGEM3 CMIP6 experiments. The modelled onset and retreat dates agree well with observations in the North American Monsoon but not in the Indian Monsoon. The start and end of the modelled MSD in southern Mexico and Central America is delayed by one pentad and has a stronger bimodal signal than observed.
Painful temporomandibular joint overloading induces structural remodeling in the pericellular matrix of that joint's chondrocytes
Authors: Franklin Melissa , Sperry Megan M. , Phillips Evan , Granquist Eric J. , Marcolongo Michele , Winkelstein Beth A.
Published: April 2021

Mechanical stress to the temporomandibular joint (TMJ) is an important factor in cartilage degeneration, with both clinical and preclinical studies suggesting that repeated TMJ overloading could contribute to pain, inflammation, and/or structural damage in the joint. However, the relationship between pain severity and early signs of cartilage matrix microstructural dysregulation is not understood, limiting the advancement of diagnoses and treatments for temporomandibular joint‐osteoarthritis (TMJ‐OA). Changes in the pericellular matrix (PCM) surrounding chondrocytes may be early indicators of OA. A rat model of TMJ pain induced by repeated jaw loading (1 h/day for 7 days) was used to compare the extent of PCM modulation for different loading magnitudes with distinct pain profiles (3.5N—persistent pain, 2N—resolving pain, or unloaded controls—no pain) and macrostructural changes previously indicated by Mankin scoring. Expression of PCM structural molecules, collagen VI and aggrecan NITEGE neo‐epitope, were evaluated at Day 15 by immunohistochemistry within TMJ fibrocartilage and compared between pain conditions. Pericellular collagen VI levels increased at Day 15 in both the 2N (p = 0.003) and 3.5N (p = 0.042) conditions compared to unloaded controls. PCM width expanded to a similar extent for both loading conditions at Day 15 (2N,p < 0.001; 3.5N,p = 0.002). Neo‐epitope expression increased in the 3.5N group over levels in the 2N group (p = 0.041), indicating pericellular changes that were not identified in the same groups by Mankin scoring of the pericellular region. Although remodeling occurs in both pain conditions, the presence of pericellular catabolic neo‐epitopes may be involved in the macrostructural changes and behavioral sensitivity observed in persistent TMJ pain.
Pancreas cancer: Therapeutic trials in metastatic disease
Authors: Smithy James W. , O'Reilly Eileen M.
Published: April 2021

Metastatic pancreatic ductal adenocarcinoma (PDAC) is a major cause of cancer‐related mortality in 2021. Cytotoxic therapies are the therapeutic mainstay for PDAC. The recent approval of olaparib as maintenance therapy for germlineBRCA1/2‐mutated PDAC and pembrolizumab for mismatch repair deficient PDAC represent molecularly targeted approaches for this disease. Investigational therapeutic strategies include targeting the stroma, metabolism, tumor microenvironment, and the immune system, and selected approaches are reviewed herein.
Trends in the utilization of neoadjuvant therapy for pancreatic ductal adenocarcinoma
Authors: Brown Zachary J. , Cloyd Jordan M.
Published: April 2021

For patients with localized pancreatic cancer, neoadjuvant therapy (NT) is increasingly delivered before surgery to maximize the receipt of multimodality therapy and the odds of a margin‐negative resection. Three decades of refining the use of NT have led to its acceptance as a valid treatment approach for pancreatic adenocarcinoma. In this review, we discuss the rationale for and recent global trends in the utilization of NT for patients with pancreatic cancer.