bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and description of Selenomonas timonae sp. nov., a novel Selenomonas species detected in a gingivitis patient
Authors: Antezack Angéline , Boxberger Manon , Ben Khedher Mariem , La Scola Bernard , Monnet-Corti Virginie
Published: October 2021

A Gram-stain-negative bacterium, designated strain Marseille-Q3039T, was isolated from subgingival dental plaque of a woman with gingivitis in Marseille, France. Strain Marseille-Q3039T was found to be an anaerobic, motile and spore-forming crescent-shaped bacterium that grew at 25–41.5 °C (optimum, 37 °C), pH 5.5–8.5 (optimum, pH 7.5) and salinity of 5.0 g l−1 NaCl. The results of 16S rRNA gene sequence analysis revealed that strain Marseille-Q3039T was closely related to

Selenomonas infelix

ATCC 43532T (98.42 % similarity),

Selenomonas dianae

ATCC 43527T (97.25 %) and Centipedia periodontii DSM 2778T (97.19 %). The orthologous average nucleotide identity and digital DNA–DNA hybridization relatedness between strain Q3039T and its closest phylogenetic neighbours were respectively 84.57 and 28.2 % for

S. infelix

ATCC 43532T and 83.93 and 27.2 % for

C. periodontii

DSM 2778T. The major fatty acids were identified as C13 : 0 (27.7 %), C15 : 0 (24.4 %) and specific C13 : 0 3-OH (12.3 %). Genome sequencing revealed a genome size of 2 351 779 bp and a G+C content of 57.2 mol%. On the basis of the results from phenotypic, chemotaxonomic, genomic and phylogenetic analyses and data, we concluded that strain Marseille-Q3039T represents a novel species of the genus

Selenomonas

, for which the name Selenomonas timonae sp. nov. is proposed (=CSUR Q3039=CECT 30128).
Genetic evidence for the involvement of Dicer-like 2 and 4 as well as Argonaute 2 in the Nicotiana benthamiana response against Pelargonium line pattern virus
Authors: Pérez-Cañamás Miryam , Hevia Elizabeth , Katsarou Konstantina , Hernández Carmen
Published: October 2021

In plants, RNA silencing functions as a potent antiviral mechanism. Virus-derived double-stranded RNAs (dsRNAs) trigger this mechanism, being cleaved by Dicer-like (DCL) enzymes into virus small RNAs (vsRNAs). These vsRNAs guide sequence-specific RNA degradation upon their incorporation into an RNA-induced silencing complex (RISC) that contains a slicer of the Argonaute (AGO) family. Host RNA dependent-RNA polymerases, particularly RDR6, strengthen antiviral silencing by generating more dsRNA templates from RISC-cleavage products that, in turn, are converted into secondary vsRNAs by DCLs. Previous work showed that Pelargonium line pattern virus (PLPV) is a very efficient inducer and target of RNA silencing as PLPV-infected Nicotiana benthamiana plants accumulate extraordinarily high amounts of vsRNAs that, strikingly, are independent of RDR6 activity. Several scenarios may explain these observations including a major contribution of dicing versus slicing for defence against PLPV, as the dicing step would not be affected by the RNA silencing suppressor encoded by the virus, a protein that acts via vsRNA sequestration. Taking advantage of the availability of lines of N. benthamiana with DCL or AGO2 functions impaired, here we have tried to get further insights into the components of the silencing machinery that are involved in anti-PLPV-silencing. Results have shown that DCL4 and, to lesser extent, DCL2 contribute to restrict viral infection. Interestingly, AGO2 apparently makes even a higher contribution in the defence against PLPV, extending the number of viruses that are affected by this particular slicer. The data support that both dicing and slicing activities participate in the host race against PLPV.
The role of Akkermansia muciniphila in obesity, diabetes and atherosclerosis
Authors: Hasani Alka , Ebrahimzadeh Saba , Hemmati Fatemeh , Khabbaz Aytak , Hasani Akbar , Gholizadeh Pourya
Published: October 2021

Alteration in the composition of the gut microbiota can lead to a number of chronic clinical diseases.

Akkermansia muciniphila

is an anaerobic bacteria constituting 3–5% of the gut microbial community in healthy adults. This bacterium is responsible for degenerating mucin in the gut; its scarcity leads to diverse clinical disorders. In this review, we focus on the role of

A. muciniphila

in diabetes, obesity and atherosclerosis, as well as the use of this bacterium as a next-generation probiotic. In regard to obesity and diabetes, human and animal trials have shown that

A. muciniphila

controls the essential regulatory system of glucose and energy metabolism. However, the underlying mechanisms by which

A. muciniphila

alleviates the complications of obesity, diabetes and atherosclerosis are unclear. At the same time, its abundance suggests improved metabolic disorders, such as metabolic endotoxemia, adiposity insulin resistance and glucose tolerance. The role of

A. muciniphila

is implicated in declining aortic lesions and atherosclerosis. Well-characterized virulence factors, antigens and cell wall extracts of

A. muciniphila

may act as effector molecules in these diseases. These molecules may provide novel mechanisms and strategies by which this bacterium could be used as a probiotic for the treatment of obesity, diabetes and atherosclerosis.
Escherichia coli type-1 fimbriae are critical to overcome initial bottlenecks of infection upon low-dose inoculation in a porcine model of cystitis
Authors: Stærk Kristian , Grønnemose Rasmus Birkholm , Nielsen Thomas Kastberg , Petersen Nicky Anúel , Palarasah Yaseelan , Torres-Puig Sergi , Møller-Jensen Jakob , Kolmos Hans Jørn , Lund Lars , Andersen Thomas Emil
Published: October 2021

Most uropathogenic

Escherichia coli

(UPEC) express type-1 fimbriae (T1F), a key virulence factor for urinary tract infection (UTI) in mice. Evidence that conclusively associates this pilus with uropathogenesis in humans has, however, been difficult to obtain. We used an experimental porcine model of cystitis to assess the role of T1F in larger mammals more closely related to humans. Thirty-one pigs were infected with UPEC strain UTI89 or its T1F deficient mutant, UTI89ΔfimH, at inoculum titres of 102 to 108 colony forming units per millilitre. Urine and blood samples were collected and analysed 7 and 14 days post-inoculation, and whole bladders were removed at day 14 and analysed for uroepithelium-associated UPEC. All animals were consistently infected and reached high urine titres independent of inoculum titre. UTI89ΔfimH successfully colonized the bladders of 1/6 pigs compared to 6/6 for the wild-type strain. Intracellular UPEC were detectable in low numbers in whole bladder explants. In conclusion, low doses of UPEC are able to establish robust infections in pigs, similar to what is presumed in humans. T1F are critical for UPEC to surpass initial bottlenecks during infection but may be dispensable once infection is established. While supporting the conclusions from mice studies regarding a general importance of T1F in successfully infecting the host, the porcine UTI models’ natural high, more human-like, susceptibility to infection, allowed us to demonstrate a pivotal role of T1F in initial establishment of infection upon a realistic low-inoculum introduction of UPEC in the bladder.
Frequency band coupling with high-frequency activities during seizures shifts from θ band in tonic phase to δ band in clonic phase
Authors: Hashimoto Hiroaki , Khoo Hui Ming , Yanagisawa Takufumi , Tani Naoki , Oshino Satoru , Hirata Masayuki , Kishima Haruhiko
Published: October 2021

Objective

To clarify variations in the relationship between high-frequency activities (HFAs) and low-frequency bands from the tonic to the clonic phase in focal to bilateral tonic-clonic seizures (FBTCS), using phase-amplitude coupling.

Methods

This retrospective study enrolled six patients with drug-resistant focal epilepsy who underwent intracranial electrode placement for presurgical invasive electroencephalography at Osaka University Hospital (July 2018–July 2019). We used intracranial electrodes to record seizures in focal epilepsy (11 FBTCS). The magnitude of synchronization index (SIm) and receiver-operating characteristic (ROC) analysis were used to analyze the coupling between HFA amplitude (80–250 Hz) and lower frequencies phase.

Results

The θ (4–8 Hz)-HFA SIm peaked in the tonic phase, whereas the δ (2–4 Hz)-HFA SIm peaked in the clonic phase. ROC analysis indicated that the δ-HFA SIm discriminated well the clonic from the tonic phase.

Conclusions

The main low-frequency band modulating the HFA shifted from the θ band in the tonic phase to the δ band in the clonic phase.

Significance

In FBTCS, low-frequency band coupling with HFA amplitude varies temporally. Especially, the δ band is specific to the clonic phase. These results suggest dynamically neurophysiological changes in the thalamus or basal ganglia throughout FBTCS.

Highlights

The θ band (4–8 Hz) was mainly coupled with high-frequency activity (HFA) in the tonic phase of focal to bilateral tonic-clonic seizures (FBTCS).

The δ band (2–4 Hz) was mainly coupled with HFA in the clonic phase of FBTCS.

The magnitude of the synchronization index related to δ-HFA phase-amplitude coupling discriminated well the clonic from the tonic phase.
High-throughput phenotypic screen identifies a new family of potent anti-amoebic compounds
Authors: Sauvey Conall , Ehrenkaufer Gretchen , Blevitt Jonathan , Jackson Paul , Abagyan Ruben
Published: October 2021

Entamoeba histolytica is a disease-causing parasitic amoeba which affects an estimated 50 million people worldwide, particularly in socioeconomically vulnerable populations experiencing water sanitation issues. Infection with E. histolytica is referred to as amoebiasis, and can cause symptoms such as colitis, dysentery, and even death in extreme cases. Drugs exist that are capable of killing this parasite, but they are hampered by downsides such as significant adverse effects at therapeutic concentrations, issues with patient compliance, the need for additional drugs to kill the transmissible cyst stage, and potential development of resistance. Past screens of small and medium sized chemical libraries have yielded anti-amoebic candidates, thus rendering high-throughput screening a promising direction for new drug discovery in this area. In this study, we screened a curated 80,000-compound library from Janssen pharmaceuticals against E. histolytica trophozoites in vitro, and from it identified a highly potent new inhibitor compound. Further experimentation confirmed the activity of this compound, as well as that of several structurally related compounds, originating from both the Janssen Jump-stARter library, and from chemical vendors, thus highlighting a new structure-activity relationship (SAR). In addition, we confirmed that the compound inhibited E. histolytica survival as rapidly as the current standard of care and inhibited transmissible cysts of the related model organism Entamoeba invadens. Together these results constitute the discovery of a novel class of chemicals with favorable in vitro pharmacological properties which may lead to an improved therapy against this parasite and in all of its life stages.

Author summary

The parasite Entamoeba histolytica represents a significant challenge in the field of global health. It currently infects and causes disease among millions of people worldwide, particularly those lacking access to clean water. Drugs exist to treat this disease, but nevertheless it persists as a problem, likely at least partly due to problems and downsides inherent to these drugs. Hence the search for new and better ones is needed. We report here our contribution to this search, consisting of testing a large, carefully-curated collection of tens of thousands of chemicals for their ability to kill E. histolytica. This large-scale test resulted in the identification of one of the compounds as potently anti-amoebic, capable of killing the parasite cells at extremely low concentrations. Further experimentation found several chemically-related compounds to also possess this property, and additionally found the first compound capable of killing the infective life stage of another Entamoeba parasite. These results have revealed an entire new family of chemicals with good potential for development as better drugs against this disease.
Integrative analysis identified common and unique molecular signatures in hepatobiliary cancers
Authors: Roy Nabanita , Lodh Ria , Sarma Anupam , Bhattacharyya Dhruba Kumar , Barah Pankaj
Published: October 2021

Hepatobiliary cancers (HBCs) are the most aggressive and sixth most diagnosed cancers globally. Biomarkers for timely diagnosis and targeted therapy in HBCs are still limited. Considering the gap, our objective is to identify unique and overlapping molecular signatures associated with HBCs. We analyzed publicly available transcriptomic datasets on Gallbladder cancer (GBC), Hepatocellular carcinoma (HCC), and Intrahepatic cholangiocarcinoma (ICC) to identify potential biomarkers using integrative systems approaches. An effective Common and Unique Molecular Signature Identification (CUMSI) approach has been developed, which contains analysis of differential gene expression (DEG), gene co-expression networks (GCN), and protein-protein interactions (PPIs) networks. Functional analysis of the DEGs unique for GBC, HCC, and ICC indicated that GBC is associated with cellular processes, HCC is associated with immune signaling pathways, and ICC is associated with lipid metabolic pathways. Our findings shows that the hub genes and pathways identified for each individual cancer type of the HBS are related with the primary function of each organ and each cancer exhibit unique expression patterns despite being part of the same organ system.
Measuring host immune response status by simultaneous quantitative measurement of activity of signal transduction pathways that coordinate functional activity of immune cells from innate and adaptive immune system
Authors: Bouwman Wilbert , Verhaegh Wim , van Doorn Arie , van de Stolpe Anja
Published: October 2021

For many diseases, including cancer, viral infections such as COVID-19, bacterial infections, and auto-immune diseases, the immune response is a major determinant of progression, response to therapy, and clinical outcome. Innate and adaptive immune response are controlled by coordinated activity of multiple immune cell types. The functional activity state of immune cells is determined by cellular signal transduction pathways (STPs). A novel mRNA-based signaling pathway assay platform has been developed to quantitatively measure relevant STP activities in all types of immune cells and mixed immune cell samples for experimental and diagnostic purposes. We generated a STP activity profile, termed Immune-Pathway Activity Profile (I-PAP), for a variety of immune cell types in resting and activated state, and provide a first example for use in patient samples.

Methods

The technology to measure STP activity has been described for androgen and estrogen receptor, PI3K, MAPK, TGFβ, Notch, NFκB, JAK-STAT1/2, and JAK-STAT3 pathways. STP activity was measured on Affymetrix expression microarray data from preclinical studies containing public data from different types of immune cells, resting/naïve or immune-activated in vitro, to establish I-PAPs. Subsequently data from a clinical study on rheumatoid arthritis were analyzed.

Results

I-PAPs of naïve/resting and immune-activated CD4+ and CD8+ T cells, T helper cells, B cells, NK cells, monocytes, macrophages, and dendritic cells were established and in agreement with known experimental immunobiology. In whole blood samples of rheumatoid arthritis patients TGFβ pathway activity was increased; JAK-STAT3 pathway activity was selectively increased in female patients. In naïve CD4+ Tregs TGFβ pathway activity was increased, while in memory T effector cells JAK-STAT3 pathway activity tended to increase, suggesting that these immune cell types contributed to whole blood analysis results.

Conclusion

STP assay technology (currently being converted to qPCR-based assays) makes it possible to directly measure functional activity of cells of the innate and adaptive immune response enabling quantitative assessment of the immune response of an individual patient. Envisioned utility lies in (1) prediction and monitoring of response to immunomodulatory treatments for a variety of immune-mediated diseases, including RA; (2) uncovering novel treatment targets; (3) improvement and standardization of in vitro immunology research and drug development.
Quantitative study of alpha-synuclein prion-like spreading in fully oriented reconstructed neural networks reveals non-synaptic dissemination of seeding aggregates
Authors: Courte Josquin , Le Ngoc Anh , Bousset Luc , Melki Ronald , Villard Catherine , Peyrin Jean-Michel
Published: October 2021

The trans-neuronal spread of protein aggregates in a prion-like manner underlies the progression of neuronal lesions in the brain of patients with synucleinopathies such as Parkinson’s disease. Despite being studied actively, the mechanisms of alpha-synuclein (aSyn) aggregates propagation remain poorly understood. This hinders the development of therapeutic approaches aiming at preventing the spatial progression of intracellular inclusions in neural networks. To assess the role of synaptic structures and neuron characteristics in the transfer efficiency of aggregates with seeding propensity, we developed a novel microfluidic culture system which allows for the first time to reconstruct in vitro fully oriented and synaptically connected neural networks. This is achieved by filtering axonal growth with unidirectional “axon valves” microchannels. We exposed the presynaptic compartment of reconstructed networks to well characterized human aSyn aggregates differing in size: Fibrils and Oligomers. Both aggregates were transferred to postsynaptic neurons through active axonal transport, albeit with poor efficiency. By manipulating network maturity, we compared the transfer rate of aggregates in networks with distinct levels of synaptic connectivity. Surprisingly, we found that transfer efficiency was lower in mature networks with higher synaptic connectivity. We then investigated the seeding efficiency of endogenous aSyn in the postsynaptic population. We found that exposure to Fibrils, and not Oligomers, resulted in low efficiency trans-neuronal seeding which was restricted to postsynaptic axons. Finally, we assessed the impact of neuron characteristics and aSyn expression on the propagation of aSyn aggregates. By reconstructing chimeric networks, we found that neuron characteristics, such as the brain region from which they originate or aSyn expression levels, did not significantly impact aggregates transfer, and observed no trans-neuronal seeding where the presynaptic population did not express aSyn. Overall, we demonstrate that this novel platform uniquely allows the quantitative interrogation of original aspects of the trans-neuronal propagation of seeding pathogenic entities.
Heterologous expression of Dehalobacter spp. respiratory reductive dehalogenases in Escherichia coli
Authors: Picott Katherine J. , Flick Robert , Edwards Elizabeth A.
Published: October 2021

Reductive dehalogenases (RDases) are a family of redox enzymes that are required for anaerobic organohalide respiration, a microbial process that is useful in bioremediation. Structural and mechanistic studies of these enzymes have been greatly impeded due to challenges in RDase heterologous expression, primarily because of their cobamide-dependence. There have been a few successful attempts at RDase production in unconventional heterologous hosts, but a robust method has yet to be developed. In this work we outline a novel respiratory RDase expression system using Escherichia coli as the host. The overexpression of E. coli’s cobamide transport system, btu, and RDase expression under anaerobic conditions were established to be essential for the expression of active RDases from Dehalobacter - an obligate organohalide respiring bacterium. The expression system was validated on six RDase enzymes with amino acid sequence identities ranging from >30-95%. Dehalogenation activity was verified for each RDase by assaying cell-free extracts of small-scale expression cultures on various chlorinated substrates including chloroalkanes, chloroethenes, and hexachlorocyclohexanes. Two RDases, TmrA from Dehalobacter sp. UNSWDHB and HchA from Dehalobacter sp. HCH1, were purified by nickel affinity chromatography. Incorporation of both the cobamide and iron-sulfur cluster cofactors was verified, and the specific activity of TmrA was found to be consistent with that of the native enzyme. The heterologous expression of respiratory RDases, particularly from obligate organohalide respiring bacteria, has been extremely challenging and unreliable. Here we present a relatively straightforward E. coli expression system that has performed well for a variety of Dehalobacter spp. RDases.

IMPORTANCE

Understanding microbial reductive dehalogenation is important to refine the global halogen cycle and to improve bioremediation of halogenated contaminants; however, studies of the family of enzymes responsible are limited. Characterization of reductive dehalogenase enzymes has largely eluded researchers due to the lack of a reliable and high-yielding production method. We are presenting an approach to express reductive dehalogenase enzymes from Dehalobacter, a key group of organisms used in bioremediation, in E. coli. This expression system will propel the study of reductive dehalogenases by facilitating their production and isolation, allowing researchers to pursue more in-depth questions about the activity and structure of these enzymes. This platform will also provide a starting point to improve the expression of reductive dehalogenases from many other organisms.
seRNAPAM-1regulates skeletal muscle satellite cell activation and aging throughtransregulation ofTimp2expression synergistically with Ddx5
Authors: So Karl Kam Hei , Huang Yile , Zhang Suyang , He Liangqiang , Li Yuying , Chen Xiaona , Zhao Yu , Ding Yingzhe , Zhou Jiajian , Yuan Jie , Sham Mai Har , Sun Hao , Wang Huating
Published: October 2021

Muscle satellite cells (SCs) are responsible for muscle homeostasis and regeneration; and lncRNAs play important roles in regulating SC activities. Here in this study, we identifyPAM-1(Pax7 Associated Muscle lncRNA) that is induced in activated SCs to promote SC activation into myoblast cells upon injury.PAM-1is generated from a myoblast specific super-enhancer (SE); as a seRNA it binds with a number of target genomic loci predominantly intrans. Further studies demonstrate that it interacts with Ddx5 to tetherPAM-1SE to it inter-chromosomal targetsTimp2 and Vimto activate the gene expression. Lastly, we show thatPAM-1expression is increased in aging SCs, which leads to enhanced inter-chromosomal interaction and target genes up-regulation. Altogether, our findings identifyPAM-1as a previously unknown lncRNA that regulates both SC activation and aging through itstransgene regulatory activity.
High-throughput Activity Assay for Screening Inhibitors of the SARS-CoV-2 Mac1 Macrodomain
Authors: Dasovich Morgan , Zhuo Junlin , Goodman Jack A. , Thomas Ajit , McPherson Robert Lyle , Jayabalan Aravinth Kumar , Busa Veronica F. , Cheng Shang-Jung , Murphy Brennan A. , Redinger Karli R. , Tsukamoto Takashi , Slusher Barbara , Bosch Jürgen , Wei Huijun , Leung Anthony K. L.
Published: October 2021

Macrodomains are a class of conserved ADP-ribosylhydrolases expressed by viruses of pandemic concern, including coronaviruses and alphaviruses. Viral macrodomains are critical for replication and virus-induced pathogenesis; therefore, these enzymes are a promising target for antiviral therapy. However, no potent or selective viral macrodomain inhibitors currently exist, in part due to the lack of a high-throughput assay for this class of enzymes. Here, we developed a high-throughput ADP-ribosylhydrolase assay using the SARS-CoV-2 macrodomain Mac1. We performed a pilot screen which identified dasatinib and dihydralazine as ADP-ribosylhydrolase inhibitors. Importantly, dasatinib does not inhibit MacroD2, the closest Mac1 homolog in humans. Our study demonstrates the feasibility of identifying selective inhibitors based on ADP-ribosylhydrolase activity, paving the way for screening large compound libraries to identify improved macrodomain inhibitors and explore their potential as antiviral therapies for SARS-CoV-2 and future viral threats.
Sumo-mediated recruitment allows timely function of the Yen1 nuclease in mitotic cells
Authors: Dorison Hugo , Talhaoui Ibtissam , Mazón Gerard
Published: October 2021

The modification of DNA damage response proteins with Sumo is an important mechanism to orchestrate a timely and orderly recruitment of repair factors to damaged sites. After replication stress and double-strand break formation a number of repair factors are Sumoylated and interact with other Sumoylated factors, including the nuclease Yen1. Yen1 plays a critical role to ensure genome stability and unperturbed chromosome segregation by removing covalently linked DNA intermediates that are formed by homologous recombination. Here we show how this important role of Yen1 is dependent on interactions mediated by non-covalent binding to Sumoylated partners. Mutations in the motifs that allow Sumo-mediated recruitment of Yen1 impair its ability to resolve DNA intermediates and result in increased genome instability and chromosome mis-segregation.
Evolution of chlorophyll degradation is associated with plant transition to land
Authors: Schumacher Isabel , Menghini Damian , Ovinnikov Serguei , Hauenstein Mareike , Fankhauser Nick , Zipfel Cyril , Hörtensteiner Stefan , Aubry Sylvain
Published: October 2021

Colonization of land by green plants (Viridiplantae) some 500 million years ago was made possible by large metabolic and biochemical adaptations. Chlorophyll, the central pigment of photosynthesis, is highly photo-active. In order to mitigate deleterious effects of pigment accumulation, some plants have evolved a coordinated pathway to deal with chlorophyll degradation end-products, so-called phyllobilins. This pathway has been so far mostly unravelled inArabidopsis thaliana. Here, large-scale comparative phylogenomic coupled to an innovative biochemical characterization strategy of phyllobilins allow a better understanding how such a pathway appeared in Viridiplantae. Our analysis reveals a stepwise evolution of the canonical pheophorbideamonooxygenase/phyllobilin pathway. It appears to have evolved gradually, first in chlorophyte’s chloroplasts, to ensure multicellularity by detoxifying chlorophyll catabolites, and in charophytes outside chloroplasts to allow adaptation of embryophytes to land. At least six out of the eight genes involved in the pathway were already present in the last common ancestor of green plants. This strongly suggests parallel evolution of distinct enzymes catalysing similar reactions in various lineages, particularly for the dephytylation step. Together, our study suggests that chlorophyll degradation accompanied the transition from water to land, and was therefore of great importance for plant diversification.
Zika virus impacts extracellular vesicle composition and cellular gene expression in macaque early gestation trophoblasts
Authors: Block Lindsey N. , Schmidt Jenna Kropp , McKeon Megan C. , Bowman Brittany D. , Wiepz Gregory J. , Golos Thaddeus G.
Published: October 2021

Zika virus (ZIKV) infection at the maternal-placental interface is associated with adverse pregnancy outcomes including fetal demise and pregnancy loss. To determine how infection impacts placental trophoblasts, we utilized rhesus macaque trophoblast stem cells (TSC) that can be differentiated into early gestation syncytiotrophoblasts (ST) and extravillous trophoblasts (EVT). TSCs and STs, but not EVTs, were highly permissive to productive infection with ZIKV strain DAK AR 41524. The impact of ZIKV on the cellular transcriptome showed that infection of TSCs and STs increased expression of immune related genes, including those involved in type I and type III interferon responses. ZIKV exposure altered extracellular vesicle (EV) protein, mRNA, and miRNA cargo, regardless of productive infection. These findings suggest that early gestation macaque TSCs and STs are permissive to ZIKV infection, and that EV analysis may provide a foundation for identifying non-invasive biomarkers of placental infection in a highly translational model.
Characterization of divalent cation interactions with AASTY native nanodiscs
Authors: Timcenko Milena , Autzen Anton A. A. , Autzen Henriette E.
Published: October 2021

Amphiphilic copolymers show promise in extracting membrane proteins directly from lipid bilayers into ‘native nanodiscs’. However, many such copolymers are polyanionic and sensitive to divalent cations, limiting their applicability. We characterize the Ca2+ and Mg2+ sensitivity of poly(acrylic acid-co-styrene) (AASTY) copolymers with analytical UV and fluorescent size exclusion chromatography, enabling us to separate signals from nanodiscs, copolymers, and soluble aggregates. We find that divalent cations promote aggregation and precipitation of both free and lipid bound copolymers. We see that excess, free copolymer acts as a ‘cation sink’ that protects nanodiscs from Ca2+ induced aggregation. Removal of the free copolymer through dialysis induces aggregation that can be mitigated by KCl. Finally, we find that the nanodisc size is dynamic and dependent on lipid concentration. Our results offer insight to nanodisc behaviour, and can help guide experimental design, aimed at mitigating the shortcomings inherent in negatively charged nanodisc forming copolymers.
Screening coffee genotypes for Cercospora coffeicola resistance in Brazil
Authors: Ramos Juliana Barros , Resende Mario Lucio Vilela de , Botelho Deila Magna dos Santos , Pereira Renata Cristina Martins , Reichel Tharyn , Balieiro André Augusto Ferreira , Botega Gustavo Pucci , Rezende Abrahão Juliana Costa de
Published: October 2021

Several efforts have been made by many researchers worldwide to develop coffee plants resistant to different Cercospora species; however, studies concerning C. coffeicola, specifically, are still incipient. In the present study, a blend of strains from this pathogen was inoculated into 18 Brazilian commercial cultivars, a coffee clone of Arabica, as well as into 41 accessions from the Germplasm Collection of Minas Gerais, to evaluate the genetic resistance ability within the population and select superior genotypes for the breeding program. After predicting genotypic values of the evaluated material, the most efficient way to select genotypes based on the data of severity to brown eye spot (BES) was also examined. Moreover, the action of defense mechanisms against C. coffeicola attacks was investigated by assessing the levels of total soluble phenolic compounds and soluble lignin in contrasting genotypes regarding disease susceptibility. Based on the results, the accession MG 1207 Sumatra demonstrated an intrinsic genetic capacity to maintain low levels of severity to brown eye spot. This genotype can thus substantially contribute to the development of new cultivars, which may lead to reduced use of pesticides. This study also evidenced that four evaluations of severity is enough to reach accuracy and efficiency for the severity of BES, thus providing expressive genetic gains. Finally, it is suggested that the levels of lignin and phenolic compounds are not associated with the resistance of coffee genotypes to brown eye spot.
Role of TLR4 signaling on Porphyromonas gingivalis LPS-induced cardiac dysfunction in mice
Authors: Matsuo Ichiro , Kawamura Naoya , Ohnuki Yoshiki , Suita Kenji , Ishikawa Misao , Matsubara Takehiro , Mototani Yasumasa , Ito Aiko , Hayakawa Yoshio , Nariyama Megumi , Morii Akinaka , Kiyomoto Kenichi , Tsunoda Michinori , Gomi Kazuhiro , Okumura Satoshi
Published: October 2021

Oral infections, particularly periodontitis, are a well-established risk factor for cardiovascular diseases, although the molecular mechanisms involved remain elusive. The aims of the present study were to investigate the effects of lipopolysaccharide derived from Porphyromonas gingivalis (PG-LPS) on cardiac function in mice, and to elucidate the underlying mechanisms. Mice (C57BL/6) were injected with PG-LPS (0.8 mg/kg/day) with or without an inhibitor of Toll-like receptor 4 (TLR4) signaling (TAK-242, 0.8 mg/kg/day) for 4 weeks. Left ventricular ejection function was significantly decreased at 1 week (from 67 ± 0.5 to 58 ± 1.2 %) and remained low at 4 weeks (57 ± 1.0 %). The number of apoptotic myocytes was increased (approximately 7.4-fold), the area of fibrosis was increased (approximately 3.3-fold) and the number of 8-hydroxydeoxyguanosine-positive myocytes, a sensitive indicator of oxidative DNA damage, was increased (approximately 7.6-fold) at 4 weeks in the heart of PG-LPS treated mice. However, levels of various serum pro-inflammatory cytokines in PG-LPS-treated mice were similar to those in control mice. The impairment of cardiac function in PG-LPS-treated mice appears to involve activation of TLR4-NADPH oxidase (NOX) 4 signaling, leading to abundant production of reactive oxygen species and Ca2+ leakage from sarcoplastic reticulumn induced by calmodulin kinase II (CaMKII)-mediated phosphorylation of phospholamban (at Thr-17) and ryanodine receptor 2 (at Ser-2448). Pharmacological inhibition of TLR4 with TAK-242 attenuated the changes in cardiac function in PG-LPS-treated mice. Our results indicate that TLR4-NOX4 signaling may be a new therapeutic target for treatment of cardiovascular diseases in patients with periodontitis.
Evolutionary sweeps of subviral parasites and their phage host bring unique parasite variants and disappearance of a phage CRISPR-Cas system
Authors: Angermeyer Angus , Hays Stephanie G. , Nguyen Maria H.T. , Johura Fatema-tuz , Sultana Marzia , Alam Munirul , Seed Kimberley D.
Published: October 2021

Vibrio cholerae is a significant threat to global public health in part due to its propensity for large-scale evolutionary sweeps where lineages emerge and are replaced. These sweeps may originate from the Bay of Bengal where bacteriophage predation and the evolution of anti-phage counter defenses is a recurring theme. The bacteriophage ICP1 is a key predator of epidemic V. cholerae and is notable for acquiring a CRISPR-Cas system to combat PLE, a defensive subviral parasite encoded by its V. cholerae host. Here we describe the discovery of five previously unknown PLE variants, including one found during recent surveillance of patient samples in Bangladesh. We also observed a lineage sweep of PLE negative V. cholerae occurring within a patient population in under a year which coincided with a loss of ICP1’s CRISPR-Cas system. These findings reinforce the importance of surveillance to better understand the selective pressures that drive pandemic cholera.
Crystal structure of methyl 1,3-benzoxazole-2-carboxylate
Authors: Poirot Alexandre , Saffon-Merceron Nathalie , Leygue Nadine , Benoist Eric , Fery-Forgues Suzanne
Published: October 2021

The title compound, C9H7NO3, crystallizes in the monoclinic (P21) space group. In the crystal, the almost planar molecules display a flattened herringbone arrangement. Stacking molecules are slipped in the lengthwise and widthwise directions and are linked by π–π interactions [d(Cg...Cg = 3.6640 (11) Å]. The structure is characterized by strong C—H...N and weak C—H...O hydrogen bonds, and further stabilized by C–O...π interactions.
Board characteristics, audit committee attributes and firm performance: empirical evidence from emerging economy
Authors: Fariha Rifat , Hossain Md. Mukarrom , Ghosh Ratan
Published: October 2021

Purpose

This study is designed and directed to analyze the effect of board characteristics and audit committee attributes on the firm performance of publicly listed commercial banks of Bangladesh.

Design/methodology/approach

Thirty publicly listed commercial banks of Dhaka Stock Exchange (DSE) have been taken as sample for this study. Data have been collected from annual reports between 2011 and 2017 of the assessed banks. Pooled OLS model has been used for running regression model of this study.

Findings

Board independence has a negative and significant relationship with ROA and Tobin's Q. However, Board Independence has a positive and significant relationship with Stock Return. On the other hand, Board Diversity has a negative and significant relationship with ROA and ROE, which implies inefficiency of diversified board members in the context of Bangladesh. Family duality has a positive and significant relationship with ROA and a negative and significant relationship with Stock return. Board Meeting has a positive and significant relationship with ROA. Audit Committee Size has a negative and significant relationship with Tobins' Q. Independence of audit committee chairman has a negative and significant relationship with Tobin's Q and Stock Returns. Presence of non-executive directors and number of audit meetings have no significant relationship with any of the predicted variables.

Research limitations/implications

Among all variables of the board characteristics, role of independent directors and participation of female directors have conflicting results in this study. This has raised a question about the fair appointment independent directors and their objective view on the board. Female directors' role is not convincing in the context of Bangladesh as most of the commercial banks are family-owned. Policymakers can tighten and supervise the appointment of independent directors to ensure good governance in the banking sector. Moreover, role of audit committee and independence of audit committee chairman have generated conflicting results in terms of market-based performance measure.

Originality/value

Banking sector of Bangladesh experiences huge corruption in the form of excessive NPLs and poor management quality which results in low profit for the firm. This study has explored the problems of management quality and flaws of audit committee which is hampering overall growth of banking industry. Improvement of independent directors' appointment and audit committee formation and reporting will certainly help banking industry of Bangladesh to improve overall performance.
Antecedents and consequences of perceived job security of professional accountants
Authors: Shahid Ahmad Usman , Tufail Hafiza Sobia , Shahid Jawad , Ismail Aimen
Published: October 2021

Purpose

The purpose of this study is to develop and empirically test a theoretical model of antecedents and consequences of perceived job security of professional accountants. This study contributes to the literature by examining the mediating role of perceived job security between the reward management system and the ethical job performance of professional accountants.

Design/methodology/approach

A survey was used to collect responses from professional accountants at small- and medium-tier accounting firms in Pakistan. Of the total 313 circulated research instruments, 270 were completed producing a response rate of 86%. The hypotheses were tested by performing structural equation modeling, confirmatory factor analysis and correlation using SPSS 24 and AMOS 25.

Findings

Findings specify that the perceived job security of professional accountants partially and fully mediates the relationship between their ethical job performance and intrinsic and rewards, respectively. Additionally, reward management systems including intrinsic and extrinsic rewards have a significant impact on the ethical job performance of professional accountants.

Practical implications

The findings of this study may have significant implications for researchers for examining the subjects' perceived job security in enhancing the overall performance of the firms. The findings may also benefit domestic and international accounting firms for recognizing the importance of rewards and job security for enhancing the ethical performance of accountants.

Originality/value

This study is the first to provide empirical evidence for the importance of perceived job security for professional accountants in Pakistan. The current research also provides sharper insights into establishing the direct impact of both extrinsic and intrinsic rewards on professional accountants' ethical job performance.
Disability inclusiveness of early warning system: a study on flood-prone areas of Bangladesh
Authors: Chisty Musabber Ali , Nazim Ashrafuzzaman , Rahman Md. Mostafizur , Dola Syeda Erena Alam , Khan Nesar Ahmed
Published: October 2021

Purpose

Persons with disabilities face the impacts of disasters differently. Early warning systems can be one of the powerful tools to reduce the vulnerabilities of persons with disabilities and mitigate the impacts of disasters. The main objective of this study was to assess the disability inclusiveness of the current early warning system (EWS) in flood-prone areas of Bangladesh.

Design/methodology/approach

A qualitative method was focused on getting in-depth information. Persons with disabilities participated in focus group discussions (FGDs) and shared the inclusiveness and gaps of the current EWS. Through extensive literature review, a checklist was developed to conduct the FGDs. QDA Miner 6.0.6 software was used for coding and analyzing the data.

Findings

Results indicated that, though persons with disabilities have proper risk knowledge, the current monitoring and warning service, dissemination and communication, and response capability are not fully inclusive. A significant gap in the EWS was found in response capability. Even if somehow persons with disabilities manage to receive a warning about a flood, they lack the capacity to respond to the warning.

Research limitations/implications

The study proposed that to make an EWS inclusive and effective, the concerned authorities should focus on all four parts of the EWS.

Originality/value

Studies related to disability and disaster management are not very common. Conducting a qualitative study provided the persons with disabilities the opportunity to share their perspectives. Future studies can focus on vulnerability and capacity assessment of persons with disabilities to identify areas requiring interventions to enhance resilience.
Two aspects of health literacy and their importance for the use of health-promotion measures by teachers in the school setting
Authors: Hoppe-Herfurth Anne-Cathrin , Burkhardt Birgit , John Nancy , Bilz Ludwig
Published: October 2021

Purpose

Teachers are exposed to many stressors. Compared to other occupational groups, they are more frequently affected by psychosomatic complaints. In recent decades, numerous prevention and intervention measures for promoting health have been developed and implemented for this target group. However, it remains unclear how the uptake of health-promotion measures (HPMs) by teachers can be increased in order to prevent stress-related disorders. This paper examines two facets of health literacy—health awareness and health value—in terms of their importance in both the take-up and intended take-up of HPMs.

Design/methodology/approach

In the 2017/2018 school year, data were collected by paper and pencil from a representative sample of 830 teachers across all school types in the German State of Brandenburg.

Findings

Teachers who place great value on their own health show significantly higher levels of take-up and intended take-up of HPMs. The findings regarding health awareness are more heterogeneous. Further associations were found with age and psychosocial stress.

Originality/value

While there has been growing academic interest in developing HPMs for teachers, there has been relatively little focus on the factors that may influence the implementation and uptake of these measures. The paper contributes to addressing this gap by shedding light on the relevance of two facets of health literacy. Strengthening the perceived importance of health could be a starting point for increasing the use of HPMs by teachers and thus improving their health.
Menstrual knowledge and perceptions of schoolgirls in Bangladesh: do socio-economic factors really matter?
Authors: Parvin Gulsan Ara , Takashino Nina , Islam Md. Shahidul , Rahman Md. Habibur , Abedin Md. Anwarul , Basu Mrittika
Published: October 2021

Purpose

This study aims to explore whether socio-economic factors determine the level of menstrual knowledge and perceptions of schoolgirls in Bangladesh. The aim of this study is to understand how knowledge and perceptions vary with variations in the different socio-economic factors in a schoolgirl’s life such as place of residence, religion, age, grade, parents’ education, parents’ occupation, family income and even family size.

Design/methodology/approach

Data were collected from four schools (two in urban areas and two in rural areas). A total of 450 schoolgirls from grades V–X were interviewed to examine how knowledge and perceptions varied with different socio-economic aspects. Multiple logistic regression models were used to measure the associations between various socio-economic variables and perceptions of and knowledge about menstruation.

Findings

Respondents from urban areas were 4.75 times more likely and those 14–16 years old were two times more likely to report higher levels of knowledge about menstruation compared to their counterparts. Based on the father’s occupation, respondents whose father was engaged in a professional occupation were 1.983 times more likely to have a higher level of knowledge on menstruation compared to those whose fathers were in an unskilled profession. Similarly, the odds of positive perceptions on menstruation were 1.456 and 1.987 times higher, respectively, among respondents living in urban areas and those 14–16 years old, compared to their counterparts.

Originality/value

This study provides evidence that different socio-economic and even demographic factors are important in the development of menstrual knowledge and perceptions. Policy formulation and development actions related to adolescent girls’ physical and reproductive health development need to consider these factors in Bangladesh and in other developing countries, where poor knowledge and perception related to menstruation are hindering girls’ mental and physical development. This is expected that better knowledge and perception will facilitate girls’ right to have better health and social lives.
Club convergence and drivers of house prices across Turkish cities
Authors: Gunduz Lokman , Yilmaz Mustafa Kemal
Published: October 2021

Purpose

This paper aims to examine the convergence pattern of residential house prices in a panel of 55 major cities in Turkey over the period between 2010 and 2018 and to investigate the determinants of convergence club formations.

Design/methodology/approach

The authors applied the log t-test to identify the convergence clubs and estimated ordered logit model to determine the key drivers.

Findings

The results suggest that there are five convergence clubs and confirm the heterogeneity of the Turkish housing market. Istanbul, the commercial capital, and Mugla, an attractive tourist destination, are at the top of the housing market and followed by the cities located in the western part, particularly along the Aegean and Mediterranean coasts of Turkey. Moreover, the ordered logit model results point out that the differences in employment rate, climate, population density and having a metropolitan municipality play a significant role in determining convergence club membership.

Practical implications

Large-scale policy measures aiming to increase employment opportunities in rural cities of central and eastern provinces and providing lower land prices and property taxes in the metropolitan cities of Turkey can help mitigate some of the divergence in the house prices across cities.

Originality/value

The novelty of this study lies in employing a new data set at the city level containing 55 cities in Turkey, which is by far the largest in terms of city coverage among emerging market economies to implement the log t-test. It also contributes to the literature on city-specific determinants of convergence club formation in the case of an emerging economy.