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Microbial contamination of hospital surfaces is a major contributor to infectious disease transmission. This work demonstrates that superhydrophobic (Cassie‐Baxter) micro post topographies can significantly reduce cell attachment compared to flat controls. For ordered micro post arrays (post diameters 0.3 to 150 µm), the attachment of four pathogens (Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Candida albicans) from discrete contaminant droplets upon short‐term contact (15 s to 30 min) are assessed. There is a 3‐4‐log decrease in microbial attachment when reducing the micro posts diameters from 150 to 0.3 µm for all strains, with large posts (>20 µm) exhibiting similar attachment rates to flat controls. The critical, maximum feature size to prevent attachment can be tuned depending on the ratio of the cell size to post diameter. Two potential mechanisms are discussed for this size effect. First, application of the random sequential adsorption model shows that this relative post/cell size effect may be due to a reduced probability of attachment, which is theorized to be the dominant mechanism. Alternatively, a physical model is suggested for bacterial cell "pull‐off" due to surface tension forces during droplet dewetting. This work may be important for the design of non‐wetting antimicrobial surfaces within healthcare environments. [ABSTRACT FROM AUTHOR]

Securing safe water remains an important global issue. PoU (Point of Use) water purification technology using filter media is promising for treating contaminated water in areas where infrastructure development is difficult. In this study, fabrication of a porous hydroxyapatite (HAp) bulk body with a connected pore structure was attempted as a filter that has the function of purifying water contaminated with microorganisms. HAp exhibits high adsorption properties for various substances such as proteins, bacteria, and viruses. In order to introduce a continuous pore structure into the porous body, corn starch, a polysaccharide, was used as a pore-forming agent. Three-dimensional observation of the internal structure of the porous body using a confocal laser fluorescent microscope and liquid immersion technique revealed a shell-like pore structure derived from the starch and the continuous pore structure inside the porous material. A filtration test of a buffer solution containing Escherichia coli (E. coli) was conducted and the filtrate did not contain detectable concentrations of E. coli. A high virus removal rate was demonstrated in a filtration test of a buffer solution containing human coronavirus. It was demonstrated that hydroxyapatite porous materials have excellent properties for filter applications to purify water contaminated with bacteria and viruses. [ABSTRACT FROM AUTHOR]

Genome function is dynamically regulated in part by chromatin, which consists of the histones, non-histone proteins and RNA molecules that package DNA. Studies in Caenorhabditis elegans and Drosophila melanogaster have contributed substantially to our understanding of molecular mechanisms of genome function in humans, and have revealed conservation of chromatin components and mechanisms. Nevertheless, the three organisms have markedly different genome sizes, chromosome architecture and gene organization. On human and fly chromosomes, for example, pericentric heterochromatin flanks single centromeres, whereas worm chromosomes have dispersed heterochromatin-like regions enriched in the distal chromosomal 'arms', and centromeres distributed along their lengths. To systematically investigate chromatin organization and associated gene regulation across species, we generated and analysed a large collection of genome-wide chromatin data sets from cell lines and developmental stages in worm, fly and human. Here we present over 800 new data sets from our ENCODE and modENCODE consortia, bringing the total to over 1,400. Comparison of combinatorial patterns of histone modifications, nuclear lamina-associated domains, organization of large-scale topological domains, chromatin environment at promoters and enhancers, nucleosome positioning, and DNA replication patterns reveals many conserved features of chromatin organization among the three organisms. We also find notable differences in the composition and locations of repressive chromatin. These data sets and analyses provide a rich resource for comparative and species-specific investigations of chromatin composition, organization and function.

Chromatin environments differ greatly within a eukaryotic genome, depending on expression state, chromosomal location, and nuclear position. In genomic regions characterized by high repeat content and high gene density, chromatin structure must silence transposable elements but permit expression of embedded genes. We have investigated one such region, chromosome 4 of Drosophila melanogaster. Using chromatin-immunoprecipitation followed by microarray (ChIP-chip) analysis, we examined enrichment patterns of 20 histone modifications and 25 chromosomal proteins in S2 and BG3 cells, as well as the changes in several marks resulting from mutations in key proteins. Active genes on chromosome 4 are distinct from those in euchromatin or pericentric heterochromatin: while there is a depletion of silencing marks at the transcription start sites (TSSs), HP1a and H3K9me3, but not H3K9me2, are enriched strongly over gene bodies. Intriguingly, genes on chromosome 4 are less frequently associated with paused polymerase. However, when the chromatin is altered by depleting HP1a or POF, the RNA pol II enrichment patterns of many chromosome 4 genes shift, showing a significant decrease over gene bodies but not at TSSs, accompanied by lower expression of those genes. Chromosome 4 genes have a low incidence of TRL/GAGA factor binding sites and a low T(m) downstream of the TSS, characteristics that could contribute to a low incidence of RNA polymerase pausing. Our data also indicate that EGG and POF jointly regulate H3K9 methylation and promote HP1a binding over gene bodies, while HP1a targeting and H3K9 methylation are maintained at the repeats by an independent mechanism. The HP1a-enriched, POF-associated chromatin structure over the gene bodies may represent one type of adaptation for genes embedded in repetitive DNA.

This correction notice addresses errors in the affiliations and contact information of the authors of the publication titled "Long-Term Reduction of Bacterial Adhesion on Polyurethane by an Ultra-Thin Surface Modifier" in the journal Biomedicines. The correction includes updating the affiliation of Dalal Asker to include the Food Science and Technology Department at Alexandria University, as well as providing a permanent email address for her. Additionally, the misspelling of the address for Brian De La Franier and Michael Thompson has been corrected. The authors assure that these corrections do not impact the scientific conclusions of the publication. [Extracted from the article]

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