bluuebunny/crossref_metadata_2025_split huggingface dataset:
Xlrbpa, a Double-stranded RNA-binding Protein Associated with Ribosomes and Heterogeneous Nuclear RNPs
Authors: Eckmann Christian R. , Jantsch Michael F. 
Published: July 2002

We have cloned and characterized Xlrbpa, a double-stranded RNA-binding protein from Xenopus laevis. Xlrbpa is a protein of 33 kD and contains three tandemly arranged, double-stranded RNA-binding domains (dsRBDs) that bind exclusively to double-stranded RNA in vitro, but fail to bind either single-stranded RNA or DNA. Sequence data and the overall organization of the protein suggest that Xlrbpa is the Xenopus homologue of human TAR-RNA binding protein (TRBP), a protein isolated by its ability to bind to human immunodeficiency virus (HIV) TAR-RNA. In transfection assays, TRBP has also been shown to inhibit the interferon-induced protein kinase PKR possibly by direct physical interaction. To determine the function of Xlrbpa and its human homologue we studied the expression and intracellular distribution of the two proteins. Xlrbpa is ubiquitously expressed with marked quantitative differences amongst all tissues. Xlrbpa and human TRBP can be detected in the cytoplasm and nucleus by immunofluorescence staining and Western blotting.
Sedimentation gradient analyses and immunoprecipitation experiments suggest an association of cytoplasmic Xlrbpa with ribosomes. In contrast, a control construct containing two dsRBDs fails to associate with ribosomes in microinjected Xenopus oocytes. Nuclear staining of Xenopus lampbrush chromosome preparations showed the association of the protein with nucleoli, again indicating an association of the protein with ribosomal RNAs. Additionally, Xlrbpa could be located on lampbrush chromosomes and in snurposomes. Immunoprecipitations of nuclear extracts demonstrated the presence of the protein in heterogeneous nuclear (hn) RNP particles, but not in small nuclear RNPs, explaining the chromosomal localization of the protein. It thus appears that Xlrbpa is a general double-stranded RNA-binding protein which is associated with the majority of cellular RNAs, ribosomal RNAs, and hnRNAs either alone or as part of an hnRNP complex.
RNA movies: visualizing RNA secondary structure spaces.
Authors: Evers D , Giegerich R 
Published: July 2002

Abstract
MOTIVATION: RNA Movies is a system for the visualization of RNA secondary structure spaces. Its input is a script consisting of primary and secondary structure information. From this script, the system fully automatically generates animated graphical structure representations. In this way, it creates the impression of an RNA molecule exploring its own two-dimensional structure space. RESULTS: RNA Movies has been used to generate animations of a switching structure in the spliced leader RNA of Leptomonas collosoma and sequential foldings of potato spindle tuber viroid transcripts. AVAILABILITY: Demonstrations of the animations mentioned in this paper can be viewed on our Bioinformatics web server under the following address: http://BiBiServ.TechFak.Uni-Bielefeld. DE/rnamovies/. The RNA Movies software is available upon request from the authors.
Quinupristin/dalfopristin: therapeutic potential for vancomycin-resistant enterococcal infections
Authors: Moellering Robert C. 
Published: July 2002

Abstract
Vancomycin-resistant Enterococcus faecium (VREF) is an opportunistic pathogen, which causes infections among severely ill, hospitalized patients, in whom it is likely to increase the risk of progressive local or systemic disease and to worsen the prognosis. Because these organisms are often highly resistant to penicillin, ampicillin and many other antimicrobials including the glycopeptides, there are few proven therapeutic alternatives for the treatment of infection caused by VREF. Quinupristin/dalfopristin is highly active against VREF in vitro. A prolonged post-antibiotic effect, good polymorphonuclear leucocyte/macrophage penetration and slow release, and active metabolites allow this agent to be used with an 8 or 12 h dosing interval. The combined results from a Phase III non-comparative study and an emergency-use study of quinupristin/dalfopristin for the treatment of VREF infection produced a clinical response rate (cure or improvement) in 142 (73.6%) of 193 clinically evaluable patients. The baseline pathogen was eradicated or presumed eradicated from 110 of 156 (70.5%) bacteriologically evaluable patients. Fifty-two per cent of the severely ill patients in these two studies died, but no death was attributed to quinupristin/dalfopristin therapy. The most common adverse event was arthralgia (9.1%). Quinupristin/dalfopristin has demonstrated efficacy for the treatment of serious VREF infections, including those that have failed conventional therapy.
Prolonged hypoxia during cell development protects mature manganese superoxide dismutase‐deficient astrocytes from damage by oxidative stress
Authors: COPIN JEAN‐CHRISTOPHE , GASCHE YVAN , LI YIBING , CHAN PAK H. 
Published: July 2002

ABSTRACTMouse astrocytes deficient in the mitochondrial form of superoxide dismutase do not grow in culture under 20% atmospheric O2 levels. By flow cytometry, immunocytochemistry, and enzymatic analysis we have shown that the oxygen block of cell division is due to a decrease in the number of cells entering the S phase of the cell cycle and is concomitant with higher DNA oxidation and impairment of mitochondrial functions. Seeding the cells under 5% O2 until the cultures become confluent can circumvent this problem. An initial hypoxic environment increases the resistance of manganese superoxide dismutase‐deficient astrocytes to superoxide radicals artificially produced by paraquat treatment, preserves respiratory activity, and allows normoxic division during a subsequent passage. DNA oxidation is then not higher than in wild‐type control cells. However, the adaptation of the cells is not due to compensation by other enzymes of the antioxidant defense system and is specific to cells totally lacking manganese superoxide dismutase. Alteration of the phenotype by prior hypoxia exposure in the SOD2‐deficient mutant provide a unique model to study adaptative mechanisms of cellular resistance to oxygen toxicity.—Copin, J.‐C., Gasche, Y., Li, Y., Chan, P. H. Prolonged hypoxia during cell development protects mature manganese superoxide dismutase‐deficient astrocytes from damage by oxidative stress. FASEB J. 15, 525‐534 (2000)
Integrin‐associated protein (CD47/IAP) contributes to T cell arrest on inflammatory vascular endothelium under flow
Authors: TICCHIONI MICHEL , RAIMONDI VINCENT , LAMY LAURENCE , WIJDENES JOHN , LINDBERG FREDERIK P. , BROWN ERIC J. , BERNARD ALAIN 
Published: July 2002

ABSTRACTIntegrin‐associated protein (CD47/IAP) is a pentaspan molecule that regulates integrin functions. We prepared a CD47‐deficient Jurkat T cell line to assess its role in the arrest of T cells on inflammatory endothelium. Under flow conditions, constitutive arrest of CD47‐deficient cells is strongly decreased as compared to the original cell line, whereas reexpression of CD47 reestablishes their ability to stop. Moreover, cells transfected with a chimera made with the extracellular portion of CD47 and the transmembrane domain of CD7 or several truncated forms of CD47 show that the first transmembrane domain and a short cytoplasmic loop are sufficient for this process. CD47 effect is indirect and depends mainly on the α4β1/VCAM‐1 pathway, as shown by blocking antibodies. We detected on endothelium the two CD47 counter receptors known to date: thrombospondin and SIRP1α. Blocking experiments show that both are involved. Overall, CD47 participates in the constitutive arrest of T lymphocytes on inflamed vascular endothelium by up‐regulating a 4β1 integrins.—Ticchioni, M., Raimondi, V., Lamy, L., Wijdenes, J., Lindberg, F. P., Brown, E. J., Bernard, A. Integrin‐associated protein (CD47/IAP) contributes to T cell arrest on inflammatory vascular endothelium under flow. FASEB J. 15, 341‐350 (2001)
Conversation time and mental health during the COVID-19 pandemic: A web-based cross-sectional survey of Japanese employees
Authors: Izawa Shuhei , Nakamura-Taira Nanako , Yoshikawa Toru , Akamatsu Rie , Ikeda Hiroki , Kubo Tomohide 
Published: May 2022

Abstract

Objective
During the Coronavirus disease 2019 (COVID-19) pandemic, social isolation and impaired social interaction could be the factors that cause mental health problems. This study investigated the association between conversation time in daily life and mental health among Japanese employees.

Methods
In August 2021, a web-based cross-sectional survey was conducted with 1000 Japanese employees. Weekly conversation time was assessed in four domains (family members, friends, someone in the workplace, and others), and mental health was assessed using the Japanese version of the Kessler Psychological Distress Scale (K6 scale). Weekly total conversation time was calculated, and participants were assigned to one of the four conversation time categories based on quantile values to investigate the associations with poor mental health (K6 ≥ 13).

Results
The logistic regression analyses revealed that participants with short conversation times (&lt;3.5 h per week) had poorer mental health compared to those with long conversation times (&gt; 21.0 h per week), even after adjusting for confounders (OR = 2.48 [95% CI 1.31–4.71]). For the exploratory analyses of conversation time for each domain, the associations of short conversation time in the workplace with poor mental health was most robust (OR =2.02 [95% CI 1.13–3.63]).

Conclusions
Japanese employees with conversation time of &lt;3.5 h per week (i.e., 30 min per day) had poor mental health. During the COVID-19 pandemic, people have largely limited opportunities to have conversations with others, but a certain level of conversation time might be required to maintain mental health.
Injectable Dual‐Dynamic‐Bond Cross‐Linked Hydrogel for Highly Efficient Infected Diabetic Wound Healing
Authors: Yao Shasha , Zhao Yueqi , Xu Yifei , Jin Biao , Wang Monian , Yu Congcong , Guo Zhengxi , Jiang Shengnan , Tang Ruikang , Fang Xiangqian , Fan Shunwu 
Published: May 2022

AbstractDiabetic wound is a significant challenge for clinical treatment with high morbidity and mortality. Plenty of hydrogels with good biocompatibility have been widely used in diabetic wound healing. However, most of them cannot be directly absorbed and utilized by the wounds, which prolongs the regeneration time. Here a new type of healing hydrogel is developed that is based on histidine, a natural dietary essential amino acid that is significant for tissue formation. The amino acid is cross‐linked with zinc ions (Zn2+) and sodium alginate (SA) via dynamic coordinate and hydrogen bonds, respectively, forming a histidine‐SA‐Zn2+ (HSZH) hydrogel with good injectable, adhesive, biocompatible, and antibacterial properties. Application of this dual‐dynamic‐bond cross‐linked HSZH hydrogel accelerates the migration and angiogenesis of skin‐related cells in vitro. Furthermore, it significantly promotes the healing of infected diabetic wounds in vivo and uniquely allows a full repair of wounds within ≈13 days, while ≈27 days are required for the healing process of the control group. This work provides a new strategy for designing wound dressing materials, that weakly cross‐linked material based on tissue‐friendly micromolecules can heal the wounds more efficiently than highly cross‐linked materials based on long‐chain polymers.
Acid‐Responsive Nanoporphyrin Evolution for Near‐Infrared Fluorescence‐Guided Photo‐Ablation of Biofilm
Authors: Yang Mengyao , Özdemir Zulal , Kim Heejeong , Nah Sanghee , Andris Erik , Li Xingshu , Wimmer Zdeněk , Yoon Juyoung 
Published: May 2022

AbstractCombating biofilm infections remains a challenge due to the shield and acidic conditions. Herein, an acid‐responsive nanoporphyrin (PN3‐NP) based on the self‐assembly of a water‐soluble porphyrin derivative (PN3) is constructed. Additional kinetic control sites formed by the conjugation of the spermine molecules to a porphyrin macrocycle make PN3 self‐assemble into stable nanoparticles (PN3‐NP) in the physiological environment. Noteworthily, near‐infrared (NIR) fluorescence monitoring and synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) effects of PN3‐NP can be triggered by the acidity in biofilms, accompanied by intelligent transformation into dot‐like nanospheres. Thus, damage to normal tissue is effectively avoided and accurate diagnosis and treatment of biofilms is achieved successfully. The good results of fluorescence imaging‐guided photo‐ablation of antibiotic‐resistant strains methicillin‐resistant Staphylococcus aureus (MRSA) biofilms verify that PN3‐NP is a promising alternative to antibiotics. Meanwhile, this strategy also opens new horizons to engineer smart nano‐photosensitizer for accurate diagnosis and treatment of biofilms.
Catalytic Mechanism of Oxygen Vacancies in Perovskite Oxides for Lithium–Sulfur Batteries
Authors: Hou Wenshuo , Feng Pingli , Guo Xin , Wang Zhenhua , Bai Zhe , Bai Yu , Wang Guoxiu , Sun Kening 
Published: May 2022

AbstractDefective materials have been demonstrated to possess adsorptive and catalytic properties in lithium–sulfur (Li–S) batteries, which can effectively solve the problems of lithium polysulfides (LiPSs) shuttle and sluggish conversion kinetics during charging and discharging of Li–S batteries. However, there is still a lack of research on the quantitative relationship between the defect concentration and the adsorptive‐catalytic performance of the electrode. In this work, perovskites Sr0.9Ti1−xMnxO3−δ (STMnx) (x = 0.1–0.3) with different oxygen‐vacancy concentrations are quantitatively regulated as research models. Through a series of tests of the adsorptive property and electrochemical performance, a quantitative relationship between oxygen‐vacancy concentration and adsorptive‐catalytic properties is established. Furthermore, the catalytic mechanism of oxygen vacancies in Li–S batteries is investigated using density functional theory calculations and in situ experiments. The increased oxygen vacancies can effectively increase the binding energy between perovskite and LiPSs, reduce the energy barrier of LiPSs decomposition reaction, and promote LiPSs conversion reaction kinetics. Therefore, the perovskite STMn0.3 with high oxygen‐vacancy concentrations exhibits excellent LiPSs adsorptive and catalytic properties, realizing high‐efficiency Li–S batteries. This work is helpful to realize the application of the quantitative regulation strategy of defect engineering in Li–S batteries.
Ni–Co Bimetallic Hydroxide Nanosheet Arrays Anchored on Graphene for Adsorption‐Induced Enhanced Photocatalytic CO2 Reduction
Authors: Wang Mengmeng , Chen Dongyun , Li Najun , Xu Qingfeng , Li Hua , He Jinghui , Lu Jianmei 
Published: May 2022

AbstractPhotocatalytic CO2 reduction can be implemented to use CO2, a greenhouse gas, as a resource in an energy‐saving and environmentally friendly way, in which suitable catalytic materials are required to achieve high‐efficiency catalysis. Insufficient accessible active sites on the catalyst surface and inhibited electron transfer severely limit the photocatalytic performance. Therefore, porous aerogels are constructed from composites comprising different ratios of Ni–Co bimetallic hydroxide (NixCoy) grown on reduced graphene oxide (GR) into a hierarchical nanosheet‐array structure using a facile in situ growth method. Detailed characterization shows that this structure exposes numerous active sites for enhanced adsorption‐induced photocatalytic CO2 reduction. Moreover, under the synergistic effect of Ni–Co bimetallic hydroxide, the CO2 adsorption capacity as well as charge‐carrier separation and transfer are excellent. As a result, the Ni7Co3–GR catalyst exhibits highly improved catalytic performance when compared with recently reported values, with a high CO release rate of 941.5 µmol h−1 g−1 and a selectivity of 96.3% during the photocatalytic reduction of CO2. This work demonstrates a new strategy for designing nanocomposites with abundant active sites structures.
N‐Hydroxyphthalimide Catalyzed Aerobic Oxidation of Aldehydes under Continuous Flow Conditions
Authors: Nagy Bence S. , Kappe C. Oliver , Ötvös Sándor B. 
Published: May 2022

AbstractThe efficacy of synthetic methodologies is based not only on potent chemistries but also on processing strategies that amplify reaction performance and overall safety. The N‐hydroxyphtalimide‐catalyzed aerobic oxidation of aldehydes is an environmentally reliable and inexpensive approach for the synthesis of valuable carboxylic acids. However, the reaction may lead to the accumulation of significant amounts of peracid in crude product mixtures thereby generating a considerable safety hazard. Also, in the case of deactivated substrates, long reaction times, high catalyst loading, and stoichiometric additives are required to promote oxidation. Therefore, we developed a flow chemistry‐based process for N‐hydroxyphtalimide‐catalyzed aldehyde oxidations and exploited its benefits to minimize peracid buildup, thereby enhancing the process safety. By performing the aerobic oxidation of aldehydes under continuous flow conditions, chemically intensified and scalable carboxylic acid formation was obtained even in the reactions of deactivated substrates. Our findings are presented herein.magnified image
Tartramide Ligands for Copper‐Catalyzed N‐Arylation at Room Temperature
Authors: Ma Xuerui , Davies Robert P. 
Published: May 2022

AbstractReadily accessible tartramide ligands have been demonstrated to promote copper‐catalysed N‐arylation under mild conditions. In addition, the coupling protocol employs cheap and readily available pre‐catalyst, ligand, and base (NaOH), and overcomes many current limitations often associated with Ullmann coupling: it can be run with low catalyst loadings, does not require the use of excess amine, operates at room temperature, is fully homogeneous, and displays improved tolerance to air and moisture. Detailed kinetic studies using reaction progress kinetic analysis (RPKA) methods have provided insight into the factors influencing the reaction rate in terms of impact of ligand structure, reactant/catalyst dependence and catalyst (in)stability. These kinetic insights have been used in a quality‐by‐design approach for further optimization of the reaction protocol. The reaction scope was extended to 22 examples, showing broad applicability for a wide range of substituted aryl iodides with both primary and secondary amines.magnified image
Hybrid breeding and cultivar diversity in rice production in China
Authors: Huang Min 
Published: May 2022

AbstractThis study determined the effect of hybrid breeding on cultivar diversity in rice (Oryza sativa L.) production in China. The results showed that hybrid breeding led to increases in the Shannon index of cultivar diversity by 29–184% during the period 2011–2015 compared with the period 1986–1990 for 10 major hybrid rice‐producing provinces in China. There was a significant exponential relationship between the Shannon index of cultivar diversity and the number of hybrid cultivars and the total number of cultivars across the 10 provinces and the two 5‐yr periods. The results of this study also demonstrate that hybrid rice breeding resulted in a cultivar diversity that came close to saturation in some provinces, such as Anhui, Hunan, Jiangxi, and Sichuan, and highlight the urgent need for a reconsideration of the development of hybrid rice industrialization in China to avoid wasting resources caused by overbreeding.
3D Binder‐free Integrated Electrodes Prepared by Phase Separation and Laser Induction (PSLI) Method for Oxygen Electrocatalysis and Zinc–Air Battery
Authors: Sha Yang , Peng Yudong , Huang Kun , Li Lin , Liu Zhu 
Published: May 2022

AbstractDeveloping facile approaches to fit in large‐scale fabrication of efficient and durable catalytic electrodes is highly desirable for oxygen electrocatalysis and metal–air batteries. Herein, a strategy based on phase separation and laser induction is proposed to prepare 3D binder‐free integrated electrodes (IEs). The phase separation between a polybenzimidazole (PBI) solution and a coagulation bath containing metal precursors occurs to form a 3D interconnected porous catalyst precursor layer. After drying, IEs are obtained by laser induction, which simultaneously converts PBI into hierarchically porous laser‐induced graphene (HPLIG) and reduces metal precursor to tiny nanoparticles. To demonstrate the versatility of this method, IEs with different HPLIG hybrid catalyst layers and substrates are fabricated. IE‐NiFe/HPLIG and IE‐Co/HPLIG using carbon paper as a substrate exhibit superior oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) performance respectively. Flexible IE‐NiCoFe/HPLIG with OER and ORR bifunctionality using carbon cloth as the substrate is applied as an air cathode in rechargeable aqueous Zinc–air batteries (ZABs) and provides a satisfactory power density of 163 mW cm−2and cycling stability of 1800 h at 10 mA cm−2. The electrode also endows solid ZABs with good flexibility. This work offers an industrially viable solution to the challenge of rapid fabrication of IEs.
Enzyme‐Catalyzed Meinwald Rearrangement with an Unusual Regioselective and Stereospecific 1,2‐Methyl Shift
Authors: Xin Ruipu , See Willy W. L. , Yun Hui , Li Xirui , Li Zhi 
Published: May 2022

AbstractThe Meinwald rearrangement is a synthetically useful reaction but often lacks regioselectivity and stereocontrol. A significant challenge in the Meinwald rearrangement of internal epoxides is the non‐regioselective migration of different substituents to give a mixture of products. Herein, an enzyme‐catalyzed regioselective and stereospecific 1,2‐methyl shift in the Meinwald rearrangement of internal epoxides is reported. Styrene oxide isomerase (SOI) catalyzed the unique isomerization of internal epoxides through 1,2‐methyl shift without 1,2‐hydride shift to give the corresponding aldehydes and a cyclic ketone as the sole product. SOI‐catalyzed isomerization showed high stereospecificity, fully retaining the stereoconfiguration. The synthetic utility of this enzymatic Meinwald rearrangement was demonstrated by its incorporation into three new types of enantioselective cascades, to convert trans‐β‐methyl styrenes into the corresponding R‐configured alcohols, acids, or amines in high ee and yield.
Selective Stepwise Arylation of Unprotected Peptides by PtIV Complexes
Authors: Lin Xiaoxi , Haimov Elvira , Redko Boris , Vigalok Arkadi 
Published: May 2022

AbstractLPtIVF(Aryl) complexes bearing a bulky bidentate 2‐[bis(adamant‐1‐yl)phosphino]phenoxide ligand (L) demonstrate excellent reactivity and selectivity in the arylation of X−H (X=S, N) bonds of amino acid residues in unprotected peptides under mild, including aqueous, conditions. Stepwise addition of these complexes allowed a convenient one‐pot introduction of different aromatic groups in the X−H bonds of Cys and N terminus. PtIV reagents can also be used to further arylate N−H bonds in Lys and Trp providing access to peptides bearing multiple aromatic groups.