bluuebunny/crossref_metadata_2025 huggingface dataset:
mRNA Formation: 3′‐End
Authors: Wahle Elmar , Kühn Uwe
Published: March 2021

Eukaryotic mRNAs are derived from precursors synthesised by RNA polymerase II. For 3′‐end formation, precursors are cleaved by an endonuclease, and a poly(A) tail is added. This processing reaction depends on signals in the pre‐mRNA, among them the ‘polyadenylation signal’ AAUAAA. Cleavage and polyadenylation are carried out by a multiprotein complex comprising, in yeast, a minimum of 13 polypeptides, many of which recognise RNA sequence motifs around the polyadenylation site. 3′‐end processing is coupled to transcription. Alternative polyadenylation, that is cleavage and polyadenylation of a precursor RNA at any of several sites, is widespread. The choice of polyadenylation site can affect the coding sequence or, more often, 3′‐UTR length. In the latter case, stability, translational efficiency or localisation of the RNA may be affected. Histone mRNAs are an exception: Their precursors are cleaved by a partially different set of factors, and no poly(A) tail is added.

Key Concepts

The 3′‐ends of eukaryotic mRNAs are generated by processing of the primary transcript, not by transcription termination.

3′‐end processing is essential for the production of mRNAs.

3′‐end processing takes place in the cell nucleus and consists of cleavage of the primary transcript followed by addition of a poly(A) tail to the upstream cleavage product.

The machinery for 3′‐end processing is complex, comprising at least 13 polypeptides.

3′‐end processing occurs cotranscriptionally and is coupled to transcription and splicing.

Alternative polyadenylation, that is the choice of different sites for cleavage and polyadenylation, can change the protein sequence encoded by the resulting mRNAs and/or mRNA regulation.

Histone mRNAs in metazoans are the only known RNAs that are not polyadenylated; their 3′‐ends are generated by a simple cleavage reaction.
Maridesulfovibrio
Authors: Galushko Alexander , Kuever Jan
Published: March 2021

Ma.ri.de.sul.fo.vi'brio. L. neut. n.
mare
, the sea; N.L. masc. n.
Desulfovibrio
, a bacterial genus name; N.L. masc. n.
Maridesulfovibrio
, a
Desulfovibrio
‐like bacterium from the sea.

Desulfobacterota / Desulfovibrionia / Desulfovibrionales / Desulfovibrionaceae / Maridesulfovibrio

Cells are vibrio to rod shaped, 0.5–1.0 × 1.0–5.5 μm. Occur singly, in pairs, or in chains. Spore formation is not observed. Stain Gram‐negative. Cells are motile by a single polar flagellum. Strictly anaerobic, having both respiratory and fermentative types of metabolism. Chemoorganoheterotrophs, using lactate, pyruvate, and often ethanol as electron donors and carbon sources; organic compounds are incompletely oxidized to acetate. Some species can also use fumarate, succinate, malate, choline, fructose, glycerol, and alanine. Propanol and butanol are only oxidized to their corresponding carboxylic acids. H
2
can serve as an electron donor in the presence of acetate as an organic carbon source (chemolithoheterotrophic growth). Growth on formate also requires acetate as a carbon source. Sulfate, sulfite, and often thiosulfate serve as terminal electron acceptors and are reduced to sulfide. Some species use sulfur and fumarate. Reduction of ferric iron is not coupled to growth. In the absence of an external electron acceptor, growth occurs by fermentation of lactate, pyruvate, fumarate (some species), and malate (some species). Desulfoviridin is present. Mesophilic, the optimum temperature for growth is 20–40°C. Neutrophilic (most species) and slightly acidotolerant (one species), the optimum pH for growth is 5.8–7.8. Media containing a reductant are required for growth. Occurs in anoxic sediment of brackish water and marine habitats.

DNA G + C content (mol%)
: 42.3–47.7 (LC, genome).

Type species
:
Maridesulfovibrio salexigens
Waite et al. 2020
VP
(basonym:
Desulfovibrio salexigens
Postgate and Campbell 1966
AL
).
Planosporangium
Authors: Thawai Chitti
Published: March 2021

Pla.no.spo.ran'gi.um. Gr. masc. n.
planes
a wanderer; N.L. neut. n.
sporangium
sporangium, spore case; N.L. neut. n.
Planosporangium
wandering sporangium, referring to the production of sporangia with motile spores.

Actinobacteria / Actinobacteria / Micromonosporales / Micromonosporaceae / Planosporangium

The genus
Planosporangium
is a group of Gram‐stain‐positive, aerobic, and non‐acid‐fast actinomycetes that belong to the family
Micromonosporaceae
. The finger‐shaped sporangia with motile spores and globose bodies produced directly on the substrate mycelia are the dominant morphological characteristics of this genus. Aerial mycelia are usually detected in the older cultures. The taxonomic affiliation at genus level could be confirmed by its chemotaxonomic characteristic, that is, the presence of
meso
‐diaminopimelic acid and glycine incorporated in the peptidoglycan; a variety of MK‐9 and MK‐10 are the major menaquinones; iso‐C
15:0
, iso‐C
16:0
, and anteiso‐C
17:0
are the predominant fatty acids in cells with some minor fatty acid components, anteiso‐C
15:0
, and C
17:1
ω8
c
; phosphatidylethanolamine is the characteristic phospholipid in the membrane. Most members contain arabinose and xylose as diagnostic sugars, but the remaining member comprises galactose, glucose, mannose, and ribose in cell hydrolysates. Similar to other mesophilic actinomycetes,
Planosporangium
species are able to grow at pH 5–9 and 20–45°C. Tolerates 2–3% NaCl in the culture medium. Known habitats are soils.

DNA G + C content (mol%)
: 71.4–72.0 (
T
m
).

Type species
:
Planosporangium flavigriseum
Wiese et al. 2008
VP
.
Silver/Rhodium Relay Catalysis Enables C−H Functionalization of In Situ Generated Isoquinolines with Sulfoxonium Ylides: Construction of Hexahydrodibenzo[a,g]quinolizine Scaffolds
Authors: Li Quanzhe , Liu Ruixing , Wei Yin , Shi Min
Published: March 2021

Employing silver/rhodium relay catalysis strategy, an intramolecular electrophilic cyclization and C−H activation followed by cascade hydrogenation and reductive amination has been developed. The acylmethylated isoquinoline derivatives could be afforded with broad substrate scope in 23–88% yields, which could be further transformed to the core skeleton of hexahydrodibenzo[a,g]quinolizine as drug‐candidates. Moreover, this reaction was achieved in a gram‐scale. A reasonable reaction mechanism has been proposed based on a series of control and KIE experiments.

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Chemoenzymatic Production of Enantiocomplementary 2‐Substituted 3‐Hydroxycarboxylic Acids from l‐α‐Amino Acids
Authors: Pickl Mathias , Marín‐Valls Roser , Joglar Jesús , Bujons Jordi , Clapés Pere
Published: March 2021

A two‐enzyme cascade reaction plus in situ oxidative decarboxylation for the transformation of readily available canonical and non‐canonical l‐α‐amino acids into 2‐substituted 3‐hydroxycarboxylic acid derivatives is described. The biocatalytic cascade consisted of an oxidative deamination of l‐α‐amino acids by an l‐α‐amino acid deaminase from Cosenzaea myxofaciens, rendering 2‐oxoacid intermediates, with an ensuing aldol addition reaction to formaldehyde, catalyzed by metal‐dependent (R)‐ or (S)‐selective carboligases namely 2‐oxo‐3‐deoxy‐l‐rhamnonate aldolase (YfaU) and ketopantoate hydroxymethyltransferase (KPHMT), respectively, furnishing 3‐substituted 4‐hydroxy‐2‐oxoacids. The overall substrate conversion was optimized by balancing biocatalyst loading and amino acid and formaldehyde concentrations, yielding 36–98% aldol adduct formation and 91–98% ee for each enantiomer. Subsequent in situ follow‐up chemistry via hydrogen peroxide‐driven oxidative decarboxylation afforded the corresponding 2‐substituted 3‐hydroxycarboxylic acid derivatives.

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Mesenteric traction syndrome in pigs: A single‐blinded, randomized controlled trial
Authors: Strandby Rune B. , Osterkamp Jens T. F. , Ambrus Rikard , Henriksen Amelie , Goetze Jens P. , Secher Niels H. , Achiam Michael P. , Svendsen Lars‐Bo
Published: March 2021

Background

Mesenteric traction syndrome is commonly observed in patients undergoing upper abdominal surgery and is associated with severe postoperative complications. A triad of hypotension, tachycardia, and facial flushing seems provoked by prostacyclin (PGI2) release from the gut in response to mesenteric traction. The administration of nonsteroidal anti‐inflammatory drugs (NSAID) inhibits PGI2 release, stabilizing the hemodynamic response. Here, we examined the effect of mesenteric traction on splanchnic blood flow in pigs randomized to NSAID or placebo treatment.

Materials and Methods

Twenty pigs were allocated to either ketorolac or placebo treatment. Five minutes of manual mesenteric traction was applied. Plasma 6‐keto‐PGF1α, a stable metabolite of PGI2, hemodynamic variables, and regional blood flow (laser speckle contrast imaging) to the liver, stomach, small intestine, upper lip, and snout (laser Doppler flowmetry) were recorded prior to traction and 5 and 30 minutes thereafter.

Results

Both groups of pigs presented a decrease in systemic vascular resistance (P = .01), mean arterial blood pressure (P = .001), and blood flow in the gastric antrum (P = .002). Plasma 6‐keto‐PGF1α did not increase in either group (P = .195), and cardiac output, heart rate, central venous pressure, and blood flow to the liver, small intestine, upper lip, and snout remained unchanged.

Conclusion

Mesenteric traction resulted in cardiovascular depression, including reduced blood flow in the gastric antrum. Plasma 6‐keto‐PGF1α did not increase, and ketorolac administration did not alter the response to mesenteric traction. Furthers studies are needed to identify which substance is responsible for eliciting the cardiovascular response to mesenteric traction in pigs.
Deleterious effects of whole‐body vibration on the spine: A review of in vivo, ex vivo, and in vitro models
Authors: Patterson Folly , Miralami Raheleh , Tansey Keith E. , Prabhu Raj K. , Priddy Lauren B.
Published: March 2021

Occupational exposure to whole‐body vibration is associated with the development of musculoskeletal, neurological, and other ailments. Low back pain and other spine disorders are prevalent among those exposed to whole‐body vibration in occupational and military settings. Although standards for limiting exposure to whole‐body vibration have been in place for decades, there is a lack of understanding of whole‐body vibration‐associated risks among safety and healthcare professionals. Consequently, disorders associated with whole‐body vibration exposure remain prevalent in the workforce and military. The relationship between whole‐body vibration and low back pain in humans has been established largely through cohort studies, for which vibration inputs that lead to symptoms are rarely, if ever, quantified. This gap in knowledge highlights the need for the development of relevant in vivo, ex vivo, and in vitro models to study such pathologies. The parameters of vibrational stimuli (eg, frequency and direction) play critical roles in such pathologies, but the specific cause‐and‐effect relationships between whole‐body vibration and spinal pathologies remain mostly unknown. This paper provides a summary of whole‐body vibration parameters; reviews in vivo, ex vivo, and in vitro models for spinal pathologies resulting from whole‐body vibration; and offers suggestions to address the gaps in translating injury biomechanics data to inform clinical practice.
Crystal Packing‐Guided Construction of Hetero‐Oligomeric Peptidic Ensembles as Synthetic 3‐in‐1 Transporters
Authors: Shen Jie , Ye Ruijuan , Zeng Huaqiang
Published: March 2021

Strategies to generate heteromeric peptidic ensembles via a social self‐sorting process are limited. Herein, we report a crystal packing‐inspired social self‐sorting strategy broadly applicable to diverse types of H‐bonded peptidic frameworks. Specifically, a crystal structure of H‐bonded alkyl chain‐appended monopeptides reveals an inter‐chain separation distance of 4.8 Å dictated by the H‐bonded amide groups, which is larger than 4.1 Å separation distance desired by the tightly packed straight alkyl chains. This incompatibility results in loosely packed alkyl chains, prompting us to investigate and validate the feasibility of applying bulky tert‐butyl groups, modified with an anion‐binding group, to alternatively interpenetrate the straight alkyl chains, modified with a crown ether group. Structurally, this social self‐sorting approach generates highly stable hetero‐oligomeric ensembles, having alternated anion‐ and cation‐binding units vertically aligned to the same side. Functionally, these hetero‐oligomeric ensembles promote transmembrane transport of cations, anions and more interestingly zwitterionic species such as amino acids.
Drivers for spatial modelling of a critically endangered seabird on a dynamic ocean area: Balearic shearwaters are non‐vegetarian
Authors: de la Cruz Andrés , Ramos Fernando , Navarro Gabriel , Cózar Andrés , Bécares Juan , Arroyo Gonzalo Muñoz
Published: March 2021

Spatial modelling is an important research tool to improve our knowledge about the distribution of wildlife in the ocean. Using different modelling techniques (MaxEnt and a generalized linear mixed model), a predictive habitat suitability model was developed for one of the most threatened seabirds in the world: the Balearic shearwater,Puffinus mauretanicus.

Models were developed using a 10‐year dataset from the Gulf of Cádiz (on the south‐western Iberian Peninsula), a key foraging area for Balearic shearwaters during migration and the non‐breeding season.

Predictive habitat maps strongly matched the observed distribution patterns, pointing to bathymetric features as the main modelling drivers. The species was concentrated on shallow areas (up to approximately 100 m in depth) of the continental shelf, very close to the mouth of the Guadalquivir River. In contrast with previous studies, Balearic shearwater distribution in the highly dynamic Gulf of Cádiz was not correlated with areas of high chlorophyllaconcentration.

This lack of spatial correlation probably arises from the delay between the phytoplankton bloom and the response of the zooplankton and small fish that are preyed upon by Balearic shearwaters, which may result in important displacements of this trophic chain across the Gulf of Cádiz.

The analysis presented contributes to a better understanding of the spatial distribution and ecology of the critically endangered top predator in the Gulf of Cádiz and offers important information to improve management plans.
Controlling the exponentially weighted moving average S2 control chart false alarm behavior when the in‐control variance level must be estimated
Authors: Knoth Sven
Published: March 2021

Investigating the problem of setting control limits for an exponentially weighted moving average (EWMA) chart in the case of parameter uncertainty is more accessible when monitoring the variance because only one parameter has to be estimated. Simply ignoring the induced uncertainty frequently leads to control charts with poor false alarm performances. Adjusting the unconditional in‐control (IC) average run length (ARL) makes the situation even worse. Guaranteeing a minimum conditional IC ARL with some given probability is another very popular approach to solving these difficulties. However, it is very conservative as well as more complex and more difficult to communicate. We utilize the probability of a false alarm within the planned number of points to be plotted on the control chart. It turns out that adjusting this probability produces notably different limit adjustments compared to controlling the unconditional IC ARL. We then develop numerical algorithms to determine the respective modifications of the upper and two‐sided EWMA charts based on the sample variance for normally distributed data. These algorithms are made available within an R package. Finally, the impacts of the EWMA smoothing constant and the size of the preliminary sample on the control chart design and its performance are studied.
Powerful anti‐inflammatory action of luteolin: Potential increase with IL‐38
Authors: Conti Pio , Caraffa Alessandro , Gallenga Carla E. , Ross Rhiannon , Kritas Spyros K. , Frydas Ilyas , Younes Alì , Di Emidio Paolo , Ronconi Gianpaolo , Pandolfi Franco
Published: March 2021

Luteolin belongs to the flavone family originally present in some fruits and vegetables, including olives, which decrease intracellular levels of reactive oxygen species (ROS) following the activation of various stimuli. Luteolin inhibits inflammation, a complex process involving immune cells that accumulate at the site of infectious or non‐infectious injury, with alteration of the endothelium leading to recruitment of leukocytes. Cytokines have been widely reported to act as immune system mediators, and IL‐1 family members evolved to assist in host defense against infections. Interleukin (IL)‐1 and Toll‐like receptor (TLR) are involved in the innate immunity in almost all living organisms. After being synthesized, IL‐1 induces numerous inflammatory mediators including itself, other pro‐inflammatory cytokines/chemokines, and arachidonic acid products, which contribute to the pathogenesis of immune diseases. Among the 11 members of the IL‐1 family, there are two new cytokines that suppress inflammation, IL‐37 and IL‐38. IL‐38 binds IL‐36 receptor (IL‐1R6) and inhibits several pro‐inflammatory cytokines, including IL‐6, through c‐Jun N‐terminal kinase (JNK) induction and reducing AP1 and nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NFκB) activity, alleviating inflammatory diseases. Therefore, since luteolin, IL‐37 and IL‐38 are all anti‐inflammatory molecules with different signaling pathways, it is pertinent to recommend the combination of luteolin with these anti‐inflammatory cytokines in inflammation.
Evaluating the effects of microparticle addition on mycelial morphology, natural yellow pigments productivity, and key genes regulation in submerged fermentation of Monascus purpureus
Authors: Huang Jing , Guan Hong‐Wei , Huang Yue‐Ying , Lai Ke‐Sheng , Chen Hui‐Ying , Xue Han , Zhang Bo‐Bo
Published: March 2021

Morphology plays an important role in fungal fermentation and secondary metabolites biosynthesis. One novel technique, microparticle‐enhanced cultivation was successfully utilized to control the morphology of Monascus purpureus precisely and enhance the yield of yellow pigments. The production of yellow pigments increased to 554.2 U/ml when 4 g/L 5000 mesh talc added at 24 h. Field emission scanning electron microscope observation indicated that the actual effect depends on the properties of microparticle. Sharp‐edged microparticles showed better stimulatory effects than smooth, round‐shaped ones. Particle size analysis, scanning electron microscope, and cell integrity evaluation proved obvious morphological changes were induced by talc addition, including smaller mycelial size, rougher hyphae, and decreased cell integrity. Furthermore, the expression levels of MrpigG, MrpigD, MrpigE, and MrpigH were significantly upregulated by the addition of talc. It indicated that the microparticle could not only affect the mycelial morphology, but also influence the expression levels of key genes in biosynthetic pathway of Monascus yellow pigments.
Analysis and optimal design of batch and two‐column continuous chromatographic frontal processes for monoclonal antibody purification
Authors: Shi Ce , Vogg Sebastian , Lin Dong‐Qiang , Sponchioni Mattia , Morbidelli Massimo
Published: March 2021

The increasing demand for efficient and robust processes in the purification of monoclonal antibodies (mAbs) has recently brought frontal chromatography to the forefront. Applied during the polishing step, it enables the removal of high molecular weight aggregates from the target product, achieving high purities. Typically, this process is operated in batch using a single column, which makes it intrinsically subjected to a purity‐yield tradeoff. This means that high purities can only be achieved at the cost of lowering the product yield and vice versa. Recently, a two‐column continuous implementation of frontal chromatography, referred to as Flow2, was developed. Despite being able of alleviating the purity‐yield tradeoff typical of batch operations, the increase in the number of process parameters complicates its optimal design, with the risk of not exploiting its full potential. In this study, we developed an ad hoc design procedure (DP) suitable for the optimization of both batch frontal chromatography and Flow2 in terms of purity, yield, and productivity. This procedure provided similar results as a multiobjective optimization based on genetic algorithm but with lower computational effort. Then, batch and Flow2 operated at their optimal conditions were compared. Besides showing a more favorable Pareto front of yield and productivity at a specified purity, the Flow2 process demonstrated improved robustness compared to the batch process with respect to modifications in the loading linear velocity, washing buffer ionic strength and loading time, thus providing an appealing operation for integrated processes.
Antibacterial and Anti‐biofilm Activity of the Human Breast Milk Glycoprotein Lactoferrin against Group B Streptococcus
Authors: Lu Jacky , Francis Jamisha D. , Guevara Miriam A. , Moore Rebecca E. , Chambers Schuyler A. , Doster Ryan S. , Eastman Alison J. , Rogers Lisa M. , Noble Kristen N. , Manning Shannon D. , Damo Steven M. , Aronoff David M. , Townsend Steven D. , Gaddy Jennifer A.
Published: March 2021

Group B Streptococcus (GBS) is an encapsulated Gram‐positive human pathogen that causes invasive infections in pregnant hosts and neonates, as well as immunocompromised individuals. Colonization of the human host requires the ability to adhere to mucosal surfaces and circumnavigate the nutritional challenges and antimicrobial defenses associated with the innate immune response. Biofilm formation is a critical process to facilitate GBS survival and establishment of a replicative niche in the vertebrate host. Previous work has shown that the host responds to GBS infection by producing the innate antimicrobial glycoprotein lactoferrin, which has been implicated in repressing bacterial growth and biofilm formation. Additionally, lactoferrin is highly abundant in human breast milk and could serve a protective role against invasive microbial pathogens. This study demonstrates that human breast milk lactoferrin has antimicrobial and anti‐biofilm activity against GBS and inhibits its adherence to human gestational membranes. Together, these results indicate that human milk lactoferrin could be used as a prebiotic chemotherapeutic strategy to limit the impact of bacterial adherence and biofilm formation on GBS‐associated disease outcomes.
Single antiplatelet therapy with use of prasugrel in patients undergoing percutaneous coronary intervention
Authors: Otsuka Tatsuhiko , Ueki Yasushi , Kavaliauskaite Raminta , Zanchin Thomas , Bär Sarah , Stortecky Stefan , Pilgrim Thomas , Valgimigli Marco , Meier Bernhard , Heg Dik , Windecker Stephan , Räber Lorenz
Published: March 2021

Objectives

We aimed to assess the ischemic and bleeding risks of single antiplatelet therapy (SAPT) with prasugrel compared with standard dual antiplatelet therapy (DAPT) (aspirin plus clopidogrel for 1 year) in patients with chronic coronary syndrome (CCS) treated with new generation drug‐eluting stents (DES).

Background

To date, data on SAPT with potent P2Y12 inhibitors in the absence of aspirin immediately after PCI are limited.

Methods

Between January 2009 and November 2019, all CCS patients undergoing percutaneous coronary intervention (PCI) enrolled to the Bern PCI registry were considered for analysis. We performed propensity score matching in a 1:4 fashion to compare patients who received SAPT with prasugrel versus standard DAPT. The primary ischemic endpoint was a composite of cardiovascular death, myocardial infarction, and stroke and the primary bleeding endpoint was BARC 3 or 5 bleeding, both assessed at 1 year.

Results

After propensity score matching, the final study population consisted of 225 patients with SAPT and 889 with DAPT. There was no significant difference in rates of the primary ischemic (5.2% vs. 4.2%, p = .50) or the primary bleeding (1.5% vs. 2.0%, p = .60) endpoints between groups. SAPT was not associated with an increased risk of definite stent thrombosis (0.9% vs. 0.8%, p = .83).

Conclusions

Among selected CCS patients undergoing PCI with DES, SAPT with prasugrel was not associated with an excess of ischemic events compared with standard DAPT. No difference in bleeding was observed either. The results may serve as the basis for larger trials assessing the potential benefits and risks of SAPT.
High Current Production of Shewanella Oneidensis with Electrospun Carbon Nanofiber Anodes is Directly Linked to Biofilm Formation**
Authors: Erben Johannes , Wang Xinyu , Kerzenmacher Sven
Published: March 2021

We study the current production of Shewanella oneidensis MR‐1 with electrospun carbon fiber anode materials and analyze the effect of the anode morphology on the micro‐, meso‐ and macroscale. The materials feature fiber diameters in the range between 108 nm and 623 nm, resulting in distinct macropore sizes and surface roughness factors. A maximum current density of (255
71) μA cm−2 was obtained with 286 nm fiber diameter material. Additionally, micro‐ and mesoporosity were introduced by CO2 and steam activation which did not improve the current production significantly. The current production is directly linked to the biofilm dry weight under anaerobic and micro‐aerobic conditions. Our findings suggest that either the surface area or the pore size related to the fiber diameter determines the attractiveness of the anodes as habitat and therefore biofilm formation and current production. Reanalysis of previous works supports these findings.
Unveiling Luminescent IrI and RhI N‐Heterocyclic Carbene Complexes: Structure, Photophysical Specifics, and Cellular Localization in the Endoplasmic Reticulum
Authors: Daubit Isabelle Marie , Wortmann Svenja , Siegmund Daniel , Hahn Stephan , Nuernberger Patrick , Metzler‐Nolte Nils
Published: March 2021

Complexes of RhI and IrI of the [M(COD)(NHC)X] type (where M=Rh or Ir, COD=1,5‐cyclooctadiene, NHC=N‐heterocyclic carbene, and X=halide) have recently shown promising cytotoxic activities against several cancer cell lines. Initial mechanism of action studies provided some knowledge about their interaction with DNA and proteins. However, information about their cellular localization remains scarce owing to luminescence quenching within this complex type. Herein, the synthesis of two rare examples of luminescent RhI and IrI [M(COD)(NHC)I] complexes with 1,8‐naphthalimide‐based emitting ligands is reported. All new complexes are comprehensively characterized, including with single‐crystal X‐ray structures. Steric crowding in one derivative leads to two distinct rotamers in solution, which apparently can be distinguished both by pronounced NMR shifts and by their respective spectral and temporal emission signatures. When the photophysical properties of these new complexes are exploited for cellular imaging in HT‐29 and PT‐45 cancer cell lines, it is demonstrated that the complexes accumulate predominantly in the endoplasmic reticulum, which is an entirely new finding and provides the first insight into the cellular localization of such IrI(NHC) complexes.
An Efficient Synthesis of 3‐Alkylpyridine Alkaloids Enables Their Biological Evaluation
Authors: Kaplan Anna R. , Schrank Cassandra L. , Wuest William M.
Published: March 2021

3‐Alkylpyridine alkaloids (3‐APAs) isolated from the arctic sponge Haliclona viscosa are a promising group of bioactive marine alkaloids. However, due to limited bioavailability, investigations of their bioactivity have been hampered. Additionally, synthesis of a common intermediate requires the use of protecting groups and harsh conditions. In this work, we developed a simple and concise two‐step route to nine different natural and synthetic haliclocyclins. These compounds displayed modest antibiotic activity against several Gram‐positive bacterial strains.
Analysis of compatibility of dyes in mixtures by means of non‐negative matrix factorization
Authors: Charmi Fatemeh , Amirshahi Seyed Hossein
Published: March 2021

The Non‐Negative Matrix Factorization is used for analyzing the compatibility of dyes in mixtures. Samples have been collected from simulated and actual dip‐dyeing tests. First, different sets of binary mixtures of dyes with different dyeing rates have been virtually created by changing the rates of absorption of employed primaries. Hence, an exponential function has been found to be appropriate to model different exhaustion rates of dyes. Besides, data of 17 different binary mixtures of nine cationic dyes, which were obtained using the dip‐test method, have been also collected from actual dyeing process. The reflectance spectra of each dip‐test dyed samples have been converted to scalable Kubelka‐Munk function and the NNMF and Principal Component Analysis methods are employed to analyze the data. It is shown that the mixtures of fully compatible dyes could be completely represented by only one basic function that may either be extracted by Non‐Negative Matrix Factorization or Principal Component Analysis factorization methods. Oppositely, dyes with great degree of incompatibility could not be characterized by one principal vector. For the later sets of samples, the extracted Non‐Negative Matrix Factorization basis could successfully resemble the spectra of primaries. The spectral analysis of both simulated and real dyed samples show that the spectra of compatible primaries could be presented by a non‐negative basic function with the average of root mean square errors value smaller than 0.1. This finding is accordance with the known practical fact that dyes are allowed to be mixed with maximum 0.5‐unit differences in their K values.
Multidimensional Lewis Acidity: A Consistent Data Set of Chloride, Hydride, Methide, Water and Ammonia Affinities for 183 p‐Block Element Lewis Acids
Authors: Erdmann Philipp , Greb Lutz
Published: March 2021

The computed fluoride ion affinity (FIA) is a widely applied descriptor to gauge Lewis acidity. Like every other single‐parameter Lewis acidity scale, the FIA metric suffers from the one‐dimensionality, that prohibits addressing Lewis acidity by the multidimensionality it inherently requires (i. e., reference Lewis base dependency). However, a systematic screening of computed affinities other than the FIA is much less developed. Herein, we extended our CCSD(T)/CBS benchmark of different density functionals and the DLPNO‐CCSD(T) method for chloride (CIA), methide (MIA), hydride (HIA), water (WA), and ammonia (AA) affinities. The best performing methods are subsequently applied to yield nearly 800 affinities for 183 p‐block element compounds of group 13–16 with an estimated accuracy of <10 kJ mol−1. The study‘s output serves as a consistent library for qualitative analyses and a training set for future statistical approaches. A first holistic correlation analysis underscores the need for a multidimensional description of Lewis acidity.
Solar Energy Conversion through Thylakoid Membranes Wired by Osmium Redox Polymer and Indium Tin Oxide Nanoparticles
Authors: Lee Jinhwan , Shin Hyosul , Kang Chan , Kim Sunghyun
Published: March 2021

For several decades, much attention has been paid to thylakoid membranes (TMs) as photocatalysts for converting solar light to electricity. Despite extensive research, current technology provides only limited photocurrents. Here, a novel method based on TM‐composite material was developed for achieving high photocurrent. When a thin film composed of TMs, osmium redox polymer (Os‐RP), and indium tin oxide nanoparticles (ITOnp) was formed on a porous graphite surface, appreciable photocurrent as high as 0.5 mA cm−2 was achieved at 0.4 V vs. Ag/AgCl. Each component plays its own role in transferring electrons from TMs to the anode, resulting in sharp drop in photocurrent with missing any component. Optimization between these three components showed 1 : 0.5 : 30 (TM/Os‐RP/ITOnp) was the best ratio. Action spectra confirmed that TMs was the origin of photocurrent. It was inferred from blocking experiments using 3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea as an inhibitor that about 41 % of photocurrent was transferred from QA in photosystem II to the electrode via Os‐RP and ITOnp. Quantum efficiencies at 430 and 660 nm were 12.2 and 18.5 %, respectively. Turnover frequency for water oxidation depended upon the amount of the composite. A complete cell with Pt/C cathode produced Pmax of 122 μW cm−2 at 758 μA cm−2 under one sun illumination, which is the highest power density to our knowledge. This study opened a possibility of using TMs as photocatalysts for solar energy conversion.
A Protein‐Based Janus Separator for Trapping Polysulfides and Regulating Ion Transport in Lithium−Sulfur Batteries
Authors: Chen Min , Fu Xuewei , Liu Jin , Chen Zhiping , Zhong Wei‐Hong
Published: March 2021

Lithium−sulfur (Li−S) batteries are a promising candidate for the next‐generation energy storage system, yet their commercialization is primarily hindered by polysulfide shuttling and uncontrollable Li dendrite growth. Here, a protein‐based Janus separator was designed and fabricated for suppressing both the shuttle effect and dendrite growth, while facilitating the Li+ transport. The Li metal‐protecting layer was a protein/MoS2 nanofabric with high ionic conductivity and good Li+ affinity, thus capable of homogenizing the Li+ flux and facilitating the Li+ transport. The polysulfide‐trapping layer was a conductive protein nanofabric enabling strong chemical/electrostatic interactions with polysulfides. Combination of the two layers was achieved by an integrated electrospinning method, yielding a robust and integral Janus separator. As a result, a long‐lived symmetric Li|Li cell (>700 h) with stable cycling performance was demonstrated. More significantly, the resulting Li−S battery delivered greatly improved electrochemical performance, including excellent rate capacity and remarkable cycle stability (with a low decay rate of 0.063 % per cycle at 0.5 A g−1 over 500 cycles). This study demonstrates the effectiveness of the Janus separator configurations for simultaneously addressing the shuttle effect and dendrite growth issues of Li−S batteries and broadens the applications of electrospinning in electrochemistry community.
Prospective evaluation of accuracy of fine‐needle aspiration biopsy for breast lesions using the International Academy of Cytology Yokohama System for reporting breast cytopathology
Authors: Agrawal Shruti , Anthony Michael Leonard , Paul Pranoy , Singh Divya , Mehan Anoushika , Singh Ashok , Joshi Prashant Pranesh , Kumar Arvind , Syed Anjum , Ravi Bina , Rao Shalinee , Chowdhury Nilotpal
Published: March 2021

Background

Classification of breast lesions into different cytological groups can accurately be done using the International Academy of Cytology (IAC) Yokohama System for reporting breast cytopathology. Fine needle aspiration biopsy (FNAB) of breast lesions has been considered to be the primary investigation in detecting breast cancers, especially in low‐cost settings. The main objective of this study was to prospectively re‐confirm the diagnostic accuracy of breast FNAB using the IAC Yokohama system. Additionally, separate secondary subgroup analysis was done to confirm the accuracy of breast FNAB excluding lymph‐node positive and lymphadenopathy positive tumors.

Material and methods

A prospective study was done on patients undergoing biopsy of breast lesions between September 01, 2019 and November 30, 2020 (519 biopsies on 487 unique patients). Of these 519 histopathology biopsies, 505 had corresponding FNAB report of the same site. The FNAB was reported using the IAC Yokohama system and the most suitable category was allotted in every case. The rates of malignancy for each category and the accuracy of breast FNAB in diagnosing malignancy were calculated.

Results

Of the total 487 patients, 120 cases were benign on histology, while 367 were malignant. The rates of malignancy in benign, atypical, suspicious and malignant categories were 5%, 25%, 71%, and 99.7%, respectively. The diagnostic accuracy of atypical, suspicious and malignant categories was calculated as 90.1%, 95.2%, and 93.3%, respectively.

Conclusion

The high diagnostic accuracy for each BIRADS category suggest excellent accuracy for Breast FNAB using the IAC Yokohama system.
Proximity between humans and a highly medically significant snake, Russell’s viper, in a tropical rural community
Authors: Glaudas Xavier
Published: March 2021

Snakebite envenoming is a major neglected tropical health issue. The high incidence of snakebites in tropical rural communities suggests that venomous snakes and people are often in proximity but quantitative evidence is lacking. I used radio‐telemetry on a population of Russell’s vipers (Daboia russelii), one of the most medically important snakes in the world, to quantify proximity between this venomous snake and people and estimate susceptibility to snakebite envenoming in India. I observed people ≤50 m of a radio‐equipped viper in ~17% of 2,066 snake relocations. People were more frequently observed in proximity to Russell’s vipers in January and July compared to March, but all other contrasts were statistically similar. This pattern indicates that snakebite incidence, which peaks in summer in the study area, is not particularly linked to the encounter frequency between people and vipers. However, consistent with epidemiological data plantation workers were the most at‐risk part of the population. By integrating information about the locations of humans and snakes in space and time, this pioneering research highlights the need to include snake ecology into the study of the human–venomous‐snake conflict, and provides a model approach to help mitigate the burden caused by venomous snakes in the rural Tropics.
Pond chironomid communities revealed by molecular species delimitation reflect eutrophication
Authors: Takamura Kenzi , Ueno Ryuhei , Kondo Natsuko Ito , Ohbayashi Kako
Published: March 2021

Farm ponds, a valued habitat for freshwater organisms, are being negatively affected by the recent changes in the environment as well as anthropological activities. In these ponds, biodiversity researchers have tended to focus on species that prefer natural habitats and/or can be identified based on morphological characters. In contrast, this study focused on the insect family Chironomidae, which is widely distributed from clear to polluted waters of ponds, but is hard to identify morphologically as an aquatic larva. We adopted DNA barcoding and molecular species delimitation to identify every single specimen of quantitative collections. From bottom sediments of 17 ponds in summer in the Banshu Plain of Japan, a total of 62 species were delimited based on the DNA sequences of the mitochondrial COI region. Chironomid communities from these ponds were classified into four groups in a two‐dimensional ordination of multivariate analysis (NMDS). One of the dimensions was well correlated with the gradient of eutrophication, while another dimension was not clearly assigned to any general feature of the environmental gradient, but rice cultivation could possibly be involved.
Functional diversity and coexistence of herbaceous plants in wet, species‐rich savannas
Authors: Brewer John Stephen , Zee Peter
Published: March 2021

Trait differences among plant species can favor species coexistence. The role that such differences play in the assembly of diverse plant communities maintained by frequent fires remains unresolved. This lack of resolution results in part from the possibility that species with similar traits may coexist because none has a significant fitness advantage and in part from the difficulty of experimental manipulation of highly diverse assemblages dominated by perennial species. We examined a 65‐year chronosequence of losses of herbaceous species following fire suppression (and subsequent encroachment by Pinus elliottii) in three wet longleaf pine savannas. We used cluster analysis, similarity profile permutation tests, and k‐R cluster analysis to identify statistically significant functional groups. We then used randomization tests to determine if the absence of functional groups near pines was greater (or less) than expected by chance. We also tested whether tolerant and sensitive species were less (or more) likely to co‐occur by chance in areas in savannas away from pines in accordance with predictions of modern coexistence theory. Functional group richness near pines was lower than expected from random species extirpations. Wetland perennials with thick rhizomes and high leaf water content, spring‐flowering wetland forbs (including Drosera tracyi), orchids, Polygala spp., and club mosses were more likely to be absent near pines than expected by chance. C3 grasses and sedges with seed banks and tall, fall‐flowering C4 grasses were less likely to be absent near pines than expected by chance. Species sensitive to pine encroachment were more likely to co‐occur with other such species away from pines at two of the three sites. Results suggest that herb species diversity in frequently burned wet savannas is maintained in part by a weak fitness (e.g., competitive) hierarchy among herbs, and not as a result of trait differences among co‐occurring species.
The effect of high‐flow arteriovenous fistulas on systemic haemodynamics and brain oxygenation
Authors: Malik Jan , Valerianova Anna , Tuka Vladimir , Trachta Pavel , Bednarova Vladimira , Hruskova Zdenka , Slavikova Marcela , Rosner Mitchell H. , Tesar Vladimir
Published: March 2021

Aims

High‐flow arteriovenous fistula (AVF) for haemodialysis leads to profound haemodynamic changes and sometimes to heart failure (HF). Cardiac output (CO) is divided between the AVF and body tissues. The term effective CO (COef) represents the difference between CO and AVF flow volume (Qa) and better characterizes the altered haemodynamics that may result in organ hypoxia. We investigated the effects of Qa reduction on systemic haemodynamics and on brain oxygenation.

Methods and results

This is a single‐centre interventional study. Twenty‐six patients on chronic haemodialysis with high Qa (>1500 mL/min) were indicated for surgical Qa reduction for HF symptoms and/or signs of structural heart disease on echocardiography. The included patients underwent three sets of examinations: at 4 months and then 2 days prior and 6 weeks post‐surgical procedure. Clinical status, echocardiographical haemodynamic assessment, Qa, and brain oximetry were recorded. All parameters remained stable from selection to inclusion. After the procedure, Qa decreased from 3.0 ± 1.4 to 1.3 ± 0.5 L/min, P < 0.00001, CO from 7.8 ± 1.9 to 6.6 ± 1.5 L/min, P = 0.0002, but COef increased from 4.6 ± 1.4 to 5.3 ± 1.4 L/min, P = 0.036. Brain tissue oxygen saturation increased from 56 ± 11% to 60 ± 9%, P = 0.001.

Conclusions

Qa reduction led to increased COef. This was explained by a decreased proportion of CO running through the AVF in patients with Qa > 2.0 L/min. These observations were mirrored by higher brain oxygenation and might explain HF symptoms and improved haemodynamics even in asymptomatic high Qa patients.
Myocardial work index: a marker of left ventricular contractility in pressure‐ or volume overload‐induced heart failure
Authors: Lakatos Bálint Károly , Ruppert Mihály , Tokodi Márton , Oláh Attila , Braun Szilveszter , Karime Christian , Ladányi Zsuzsanna , Sayour Alex Ali , Barta Bálint András , Merkely Béla , Radovits Tamás , Kovács Attila
Published: March 2021

Aims

While global longitudinal strain (GLS) is considered to be a sensitive marker of left ventricular (LV) function, it is significantly influenced by loading conditions. We hypothesized that global myocardial work index (GMWI), a novel marker of LV function, may show better correlation with load‐independent markers of LV contractility in rat models of pressure‐induced or volume overload‐induced heart failure.

Methods and results

Male Wistar rats underwent either transverse aortic constriction (TAC; n = 12) or aortocaval fistula creation (ACF; n = 12), inducing LV pressure or volume overload, respectively. Sham procedures were performed to establish control groups (n = 12/12). Echocardiographic loops were obtained to determine GLS and GMWI. Pressure‐volume analysis with transient occlusion of the inferior caval vein was carried out to calculate preload recruitable stroke work (PRSW), a load‐independent ‘gold‐standard’ parameter of LV contractility. Myocardial samples were collected to assess interstitial and perivascular fibrosis area and also myocardial atrial‐type natriuretic peptide (ANP) and brain‐type natriuretic peptide (BNP) relative mRNA expression. Compared with controls, GLS was substantially lower in the TAC group (−7.0 ± 2.8 vs. −14.5 ± 2.5%; P < 0.001) and was only mildly reduced in the ACF group (−13.2 ± 2.4 vs. −15.4 ± 2.0%, P < 0.05). In contrast with these findings, PRSW and GMWI were comparable with sham in TAC (110 ± 26 vs. 116 ± 68 mmHg; 1687 ± 275 mmHg% vs. 1537 ± 662 mmHg%; both P = NS), while it was found to be significantly reduced in ACF (58 ± 14 vs. 111 ± 40 mmHg; 1328 ± 411 vs. 1934 ± 308 mmHg%, both P < 0.01). In the pooled population, GMWI (r = 0.70; P < 0.001) but not GLS (r = −0.23; P = 0.12) showed a strong correlation with PRSW. GLS correlated with interstitial (r = 0.61; P < 0.001) and perivascular fibrosis area (r = 0.54; P < 0.001), and also with myocardial ANP (r = 0.85; P < 0.001) and BNP relative mRNA expression (r = 0.75; P < 0.001), while GMWI demonstrated no or only marginal correlation with these parameters.

Conclusions

Being significantly influenced by loading conditions, GLS may not be a reliable marker of LV contractility in heart failure induced by pressure or volume overload. GMWI better reflects contractility in haemodynamic overload states, making it a more robust marker of systolic function, while GLS should be considered as an integrative marker, incorporating systolic function, haemodynamic loading state, and adverse tissue remodelling of the LV.
Nitrosonium and Nitronium Salts of New Mixed‐Cation Hexafluoridoantimonates(V)
Authors: Mazej Zoran , Goreshnik Evgeny
Published: March 2021

Reaction between NOSbF6 and Cu(SbF6)2 in aHF yielded NOCu(SbF6)3. In the presence of H3OSbF6, single crystals of (H3O)0.2(NO)0.8Cu(SbF6)3 were grown from a saturated aHF solution. Both salts are isotypic and crystallize in the orthorhombic space group Pnma (No. 62) at 200 K. The main feature of their crystal structures are rings of CuF6 octahedra sharing apexes with SbF6 octahedra connected into 3‐D network. Single charged cations are located inside the cavities. Reaction between 0.25NOSbF6, 0.75NO2SbF6 and Cu(SbF6)2 in aHF yielded (NO)0.25(NO2)0.75Cu(SbF6)3 upon the crystallization. It crystallizes in the cubic space group Im
(No. 204) at 200 K. Subsequent experiments with M(SbF6)2 (M=Cu, Zn) showed that, when the NO+ cations are partially or completely replaced by H3O+, the grown crystals of (H3O)0.125(NO)0.125(NO2)0.75Zn(SbF6)3 and (H3O)0.25(NO2)0.75M(SbF6)3 (M=Cu, Zn) are isotypic to (NO)0.25(NO2)0.75Cu(SbF6)3. Crystal structure of the latter demonstrates similar 3‐D structural motif as observed for the NOCu(SbF6)3 salt. The crystal structures of (H3O)0.64(NO2)0.36CuF(SbF6)2 and [Cu(H2O)6](SbF6)2 were also determined. Crystallizations of NOSbF6/O2SbF6 were carried out in aHF in different molar ratios. The crystal structure determinations of grown single crystals showed that they have the composition (NO)x(O2)1‐xSbF6 (x=0.17, 0.55 0.75) indicating that most likely all phases with x=0–1 exist. They are isotypic to NOSbF6.