Electroosmotic flow (EOF), a consequence of an imposed electric field onto an electrolyte solution in the tangential direction of a charged surface, has emerged as an important phenomenon in ...electrokinetic transport at the micro/nanoscale. Because of their ability to efficiently pump liquids in miniaturized systems without incorporating any mechanical parts, electroosmotic methods for fluid pumping have been adopted in versatile applications—from biotechnology to environmental science. To understand the electrokinetic pumping mechanism, it is crucial to identify the role of an ionically polarized layer, the so‐called electrical double layer (EDL), which forms in the vicinity of a charged solid–liquid interface, as well as the characteristic length scale of the conducting media. Therefore, in this tutorial review, we summarize the development of electrical double layer models from a historical point of view to elucidate the interplay and configuration of water molecules and ions in the vicinity of a solid–liquid interface. Moreover, we discuss the physicochemical phenomena owing to the interaction of electrical double layer when the characteristic length of the conducting media is decreased from the microscale to the nanoscale. Finally, we highlight the pioneering studies and the most recent works on electro osmotic flow devoted to both theoretical and experimental aspects.
Genome packaging by nucleosomes is a hallmark of eukaryotes. Histones and the pathways that deposit, remove, and read histone modifications are deeply conserved. Yet, we lack information regarding ...chromatin landscapes in extant representatives of ancestors of the main groups of eukaryotes, and our knowledge of the evolution of chromatin-related processes is limited. We used the bryophyte Marchantia polymorpha, which diverged from vascular plants circa 400 mya, to obtain a whole chromosome genome assembly and explore the chromatin landscape and three-dimensional genome organization in an early diverging land plant lineage. Based on genomic profiles of ten chromatin marks, we conclude that the relationship between active marks and gene expression is conserved across land plants. In contrast, we observed distinctive features of transposons and other repetitive sequences in Marchantia compared with flowering plants. Silenced transposons and repeats did not accumulate around centromeres. Although a large fraction of constitutive heterochromatin was marked by H3K9 methylation as in flowering plants, a significant proportion of transposons were marked by H3K27me3, which is otherwise dedicated to the transcriptional repression of protein-coding genes in flowering plants. Chromatin compartmentalization analyses of Hi-C data revealed that repressed B compartments were densely decorated with H3K27me3 but not H3K9 or DNA methylation as reported in flowering plants. We conclude that, in early plants, H3K27me3 played an essential role in heterochromatin function, suggesting an ancestral role of this mark in transposon silencing.
•A database combining genomic information and chromatin profiles for Marchantia•Correlations between chromatin marks and transcription are conserved in land plants•A significant portion of constitutive heterochromatin is marked by H3K27me3•Insights into the evolution of TAD organization in plants
Montgomery et al. provide a chromosome-scale genome assembly of the early diverging land plant Marchantia polymorpha. Profiling of chromatin marks shows conserved roles of active marks and suggests an ancestral association between H3K27me3 and transposons that is partly retained in Marchantia and replaced by H3K9 methylation in flowering plants.
The structural, functional, and mechanistic characterization of several types of post‐translational modifications (PTMs) is well‐documented. PTMs, however, may interact or interfere with one another ...when regulating protein function. Yet, characterization of the structural and functional signatures of their crosstalk has been hindered by the scarcity of data. To this end, we developed a unified sequence‐based predictor of 23 types of PTM sites that, we believe, is a useful tool in guiding biological experiments and data interpretation. We then used experimentally determined and predicted PTM sites to investigate two particular cases of potential PTM crosstalk in eukaryotes. First, we identified proteins statistically enriched in multiple types of PTM sites and found that they show preferences toward intrinsically disordered regions as well as functional roles in transcriptional, posttranscriptional, and developmental processes. Second, we observed that target sites modified by more than one type of PTM, referred to as shared PTM sites, show even stronger preferences toward disordered regions than their single‐PTM counterparts; we explain this by the need for these regions to accommodate multiple partners. Finally, we investigated the influence of single and shared PTMs on differential regulation of protein–protein interactions. We provide evidence that molecular recognition features (MoRFs) show significant preferences for PTM sites, particularly shared PTM sites, implicating PTMs in the modulation of this specific type of macromolecular recognition. We conclude that intrinsic disorder is a strong structural prerequisite for complex PTM‐based regulation, particularly in context‐dependent protein–protein interactions related to transcriptional and developmental processes. Availability: www.modpred.org
The dynamic cell–cell communication is essential for tissue homeostasis in normal physiological circumstances and contributes to a diversified tumor microenvironment. Although exosomes are ...extracellular vesicles that actively participate in cell–cell interaction by shutting cellular components, impacts of tumor exosomes in the context of cancer stemness remain elusive. Here, we expand colorectal cancer stem cells (CRCSCs) as cancer spheroids and demonstrate that the β‐catenin/Tcf‐4‐activated RAB27B expression is required for the secretion of CRCSC exosomes. In an exosomal RNA sequencing analysis, a switch of exosomal RNA species from retrotransposons to microRNAs (miRNAs) is identified upon expanding CRCSCs. miRNA‐146a‐5p (miR‐146a) is the major miRNA in CRCSC exosomes and exosomal miR‐146a promotes stem‐like properties and tumorigenicity by targeting Numb in recipient CRC cells. Among 53 CRC patients, those with abundant exosomal miR‐146a expression in serum exhibits higher miR‐146aHigh/NumbLow CRCSC traits, an increased number of tumor‐filtrating CD66(+) neutrophils and a decreased number of tumor‐infiltrating CD8(+) T cells. Our study elucidates a unique mechanism of tumor exosome‐mediated stemness expansion.
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The tumor microenvironment (TME) is composed of heterogeneous tumor cells and host cells interacting with each other to promote disease progression. However, diagnostic and prognostic biomarkers to monitor the cancer stem cells (CSCs)‐host interplay are lacking. Here, the authors explore the role of tumor exosomes in cancer stemness and demonstrate that RAB27B‐assisted secretion of miRNA‐dominant exosomes is one critical feature of CSCs. Importantly, they show that colorectal cancer stem cells release miR‐146a‐loaded oncogenic exosomes for reprogramming non‐CSC cells and demonstrate the clinical relevance of exosomal miR‐146a in predicting the TME of CRC patients.
Although most H. pylori infectors are asymptomatic, some may develop serious disease, such as gastric adenocarcinoma, gastric high-grade B cell lymphoma and peptic ulcer disease. Epidemiological and ...basic studies have provided evidence that infection with H. pylori carrying specific virulence factors can lead to more severe outcome. The virulence factors that are associated with gastric adenocarcinoma development include the presence, expression intensity and types of cytotoxin-associated gene A (CagA, especially EPIYA-D type and multiple copies of EPIYA-C) and type IV secretion system (CagL polymorphism) responsible for its translocation into the host cells, the genotypes of vacuolating cytotoxin A (vacA, s1/i1/m1 type), and expression intensity of blood group antigen binding adhesin (BabA, low-producer or chimeric with BabB). The presence of CagA is also related to gastric high-grade B cell lymphoma occurrence. Peptic ulcer disease is closely associated with cagA-genopositive, vacA s1/m1 genotype, babA2-genopositive (encodes BabA protein), presence of duodenal ulcer promoting gene cluster (dupA cluster) and induced by contact with epithelium gene A1 (iceA1), and expression status of outer inflammatory protein (OipA). The prevalence of these virulence factors is diverse among H. pylori isolated from different geographic areas and ethnic groups, which may explain the differences in disease incidences. For example, in East Asia where gastric cancer incidence is highest worldwide, almost all H. pylori isolates were cagA genopositive, vacA s1/i1/m1 and BabA-expressing. Therefore, selection of appropriate virulence markers and testing methods are important when using them to determine risk of diseases. This review summarizes the evidences of H. pylori virulence factors in relation with gastroduodenal diseases and discusses the geographic differences and appropriate methods of analyzing these virulence markers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The flexible solid-state battery supercapacitor hybrid (SBS) is one of the promising energy storage devices for wearable electronic devices. Surface properties of active materials play important ...roles on electrolyte/active material interaction and energy storage ability. This work applies nickel cobalt oxide (NiCo2O4) and nickel cobalt oxide@nickel molybdenum oxide (NiCo2O4@NiMoO4) as the active material for SBS. Effects of structure-directing agents (SDA) and substrates on surface properties and energy storage abilities of active materials are investigated. SDA has less influence on active material morphology while Ni foam with higher electrical conductivity is preferable as substrate. The best energy storage ability is obtained for SBS with NiCo2O4@NiMoO4 electrode prepared using ammonium fluoride with capacity of 0.68 mAh/cm2 and the maximum energy density of 70.78 Wh/kg at 3.25 kW/kg. Excellent bending ability for the device with nearly no capacitance decay under 150° bending is attained. Capacitance retention of 80% and Coulombic efficiency of higher than 95% are achieved for SBS measured in 5000 times charging/discharging process. This work firstly relates surface property of active materials to energy storage ability of SBS. It is expected that more efficient active materials and better energy storage ability can be eventually achieved by understanding effects of synthesizing parameters.
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•NiCo2O4 and NiCo2O4@NiMoO4 were used for solid-state battery supercapacitor (SBS).•The structure-directing agent and substrate effects on surface features are studied.•A SBS with NiCo2O4@NiMoO4 made using NH4F shows the highest capacity of 0.68 mAh/cm2.•Maximum energy density of 70.78 Wh/kg at 3.25 kW/kg was also got for the best SBS.•Excellent bending ability with no capacitance decay under 150° bending was got.
Subwavelength‐structured silicon and glass pillar arrays that mimic both the unique functionalities of antireflective moth eyes and superhydrophobic cicada wings have been fabricated by a simple and ...scalable colloidal templating technique. The resulting biomimetic multifunctional coatings have important technological applications ranging from solar cells to flat panel displays.
A global consensus meeting was held to review current evidence and knowledge gaps and propose collaborative studies on population-wide screening and eradication of
for prevention of gastric cancer ...(GC).
28 experts from 11 countries reviewed the evidence and modified the statements using the Delphi method, with consensus level predefined as ≥80% of agreement on each statement. The Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach was followed.
Consensus was reached in 26 statements. At an individual level, eradication of
reduces the risk of GC in asymptomatic subjects and is recommended unless there are competing considerations. In cohorts of vulnerable subjects (eg, first-degree relatives of patients with GC), a screen-and-treat strategy is also beneficial.
eradication in patients with early GC after curative endoscopic resection reduces the risk of metachronous cancer and calls for a re-examination on the hypothesis of 'the point of no return'. At the general population level, the strategy of screen-and-treat for
infection is most cost-effective in young adults in regions with a high incidence of GC and is recommended preferably before the development of atrophic gastritis and intestinal metaplasia. However, such a strategy may still be effective in people aged over 50, and may be integrated or included into national healthcare priorities, such as colorectal cancer screening programmes, to optimise the resources. Reliable locally effective regimens based on the principles of antibiotic stewardship are recommended. Subjects at higher risk of GC, such as those with advanced gastric atrophy or intestinal metaplasia, should receive surveillance endoscopy after eradication of
.
Evidence supports the proposal that eradication therapy should be offered to all individuals infected with
. Vulnerable subjects should be tested, and treated if the test is positive. Mass screening and eradication of
should be considered in populations at higher risk of GC.
The novel growth of cesium lead halide perovskite thin films, which are prepared through thousand‐layer rapid alternative deposition, is performed by developing an active perovskite film consisting ...of a layer‐by‐layer structure. This method is considerably more difficult to be implemented from the solution process. The obtained thin film morphology and characteristics are distinguished from that of the traditional a few layers and two‐material codeposition. These alternative deposited perovskites are integrated with vacuum‐deposited carrier‐transporting layers and electrodes, and all vacuum‐sublimed perovskite solar cells exhibit an outstanding power conversion efficiency of 13.0%. The use of these devices for environmental light energy harvesting provides a power conversion efficiency of 33.9% under fluorescent light illumination of 1000 lux.
Rapid alternative deposition provides new approaches for Cs‐based perovskite fabrication. The thousand‐layer CsPbI2Br thin films obtained through this method exhibit a smooth surface and high crystallinity, and the solar cell devices deliver excellent performance under both 1‐sun solar and fluorescent light illumination.
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