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Abstract Marine biofouling–the adhesion of marine organisms onto a ship hull–causes increased fuel consumption, leading to massive carbon dioxide emissions. Many attempts are made to address this issue, and antifouling polymer coatings are extensively investigated owing to their environmental friendliness. Zwitterionic polymers, polysaccharides, and polyethylene glycol are frequently used as surface coatings, demonstrating excellent marine antifouling performance. However, these hydrophilic polymer coatings have a major drawback: when exposed to sediment, various minerals are easily adsorbed by the coatings, causing them to lose their inherent antifouling properties. Amphiphilic polymer coatings have therefore been proposed as alternatives to hydrophilic polymer coatings. In this study, the synthesis of amphiphilic copolymers composed of carboxybetaine methacrylamide and trifluoroethyl methacrylate and the immobilization of these copolymers onto solid surfaces are reported. This method utilizes material‐independent surface‐coating properties and the metal complex‐forming ability of polydopamine to immobilize amphiphilic copolymers onto solid surfaces. The resulting surfaces exhibit good antifouling performance against both diatom adhesion and silt adsorption. As this is a facile and substrate‐independent method for immobilizing polymers, an expectation exists for it to be an effective platform for the coating of new marine antifouling polymers.

Abstract Background Soluble amyloid-β (Aβ) oligomers are the major toxic substances associated with the pathology of Alzheimer’s disease (AD). The ability to measure Aβ oligomer levels in the blood would provide simple and minimally invasive tools for AD diagnostics. In the present study, the recently developed Multimer Detection System (MDS) for AD, a new enzyme-linked immunosorbent assay for measuring Aβ oligomers selectively, was used to detect Aβ oligomers in the plasma of patients with AD and healthy control individuals. Methods Twenty-four patients with AD and 37 cognitively normal control individuals underwent extensive clinical evaluations as follows: blood sampling; detailed neuropsychological tests; brain magnetic resonance imaging; cerebrospinal fluid (CSF) measurement of Aβ42, phosphorylated tau protein (pTau), and total tau protein (tTau); and 11C-Pittsburgh compound B (PIB) positron emission tomography. Pearson’s correlation analyses between the estimations of Aβ oligomer levels by MDS and other conventional AD biomarkers (CSF Aβ42, pTau, and tTau, as well as PIB standardized uptake value ratio [PIB SUVR]) were conducted. ROC analyses were used to compare the diagnostic performance of each biomarker. Results The plasma levels of Aβ oligomers by MDS were higher in patients with AD than in normal control individuals, and they correlated well with conventional AD biomarkers (levels of Aβ oligomers by MDS vs. CSF Aβ42, r = −0.443; PIB SUVR, r = 0.430; CSF pTau, r = 0.530; CSF tTau, r = 0.604). The sensitivity and specificity of detecting plasma Aβ oligomers by MDS for differentiating AD from the normal controls were 78.3% and 86.5%, respectively. The AUC for plasma Aβ oligomers by MDS was 0.844, which was not significantly different from the AUC of other biomarkers (p = 0.250). Conclusions Plasma levels of Aβ oligomers could be assessed using MDS, which might be a simple, noninvasive, and accessible assay for evaluating brain amyloid deposition related to AD pathology.

Abstract HEPN–MNT, a type VII TA module, comprises the HEPN toxin and the MNT antitoxin, which acts as a nucleotidyltransferase that transfers the NMP moiety to the corresponding HEPN toxin, thereby interfering with its toxicity. Here, we report crystal structures of the Legionella pneumophila HEPN–MNT module, including HEPN, AMPylated HEPN, MNT, and the HEPN–MNT complex. Our structural analysis and biochemical assays, suggest that HEPN is a metal-dependent RNase and identify its active site residues. We also elucidate the oligomeric state of HEPN in solution. Interestingly, L. pneumophila MNT, which lacks a long C-terminal α4 helix, controls the toxicity of HEPN toxin via a distinct binding mode with HEPN. Finally, we propose a comprehensive regulatory mechanism of the L. pneumophila HEPN–MNT module based on structural and functional studies. These results provide insight into the type VII HEPN–MNT TA system.

Free-standing thin nanoplates of Bi2Te3 and Bi2Se3 were synthesized by solvothermal method. It was demonstrated that the thickness of the nanoplates can be controlled by introducing a controlled amount of polyvinylpyrrolidone (PVP) in the synthesis reaction. PVP bonds to the polar basal planes of hexagonal crystal structure of Bi2Te3 and Bi2Se3, and they suppress the growth (speed) of the hexagonal crystals in the c-axis direction. Highly anisotropic growth yielded the formation of 2-dimensional nanostructures of nanoplates. The plates were examined directly with transmission electron microscopy (TEM) with in-situ heating. These crystalline nanoplates with extremely high width to thickness ratios were found to exhibit much lower thermal stability compared to the bulk counterpart or the conventional nanoparticles as represented by the reduced melting temperature. The melting temperature of a nanoplate decreased by more than 100°C compared to the melting temperature of the bulk material. While it is widely known that the meting temperature decreases for nanoparticles with reduced sizees in all three spatial dimensions, we demonstrate that the reduction in one dimension, i.e. thickness of the platelets in the present study, is effective enough to induce much greater decrease of the melting point than the decrease as observed for the case of nanoparticles.

Development of advanced cell culture methods has gained increasing attention because it allows for efficient genetic engineering and precise regulation of animal reproduction on a cellular basis. Numerous studies have attempted to develop an advanced cell culture method. Previous studies have altered cell culture media and pretreated culture plates with functional molecules. Among them, a mussel-inspired polymer coating has been extensively utilized owing to its wide applicability. For instance, adhesion of human embryonic stem cells and neuronal cells on solid surfaces has been improved. Despite the excellent capability of the mussel-inspired polymer coating, most studies have primarily focused on mammalian cells. However, the efficacy of these coatings on the adhesion of other cell lines is yet unclear. This study aimed to assess the potential of the mussel-inspired polymer coating in the regulation of the adhesion of fish ovarian germline stem cells on solid surfaces. Solid surfaces were coated by polydopamine and poly-L-lysine, and the effect of the coatings on cellular behaviors was investigated.

Transcriptional regulator proteins are closely involved in essential survival strategies in bacteria. AcrR is a one‐component allosteric repressor of the genes associated with lipid transport and antibiotic resistance. When fatty acid ligands bind to the C‐terminal ligand‐binding cavity of AcrR, a conformational change in the N‐terminal operator‐binding region of AcrR is triggered, which releases the repressed DNA and initiates transcription. This paper focuses on the structural transition mechanism of AcrR of Mycobacterium tuberculosis upon DNA and ligand binding. AcrR loses its structural integrity upon ligand‐mediated structural alteration and bends toward the promoter DNA in a more compact form, initiating a rotational motion. Our functional characterization of AcrR and description of the ligand‐ and DNA‐recognition mechanism may facilitate the discovery of new therapies for tuberculosis.

A facile approach is examined for material-independent surface modification by using norepinephrine. pH-Induced oxidative polymerization of norepinephrine has formed adherent films on different types of material surfaces of noble metals, metal oxides, semiconductors, ceramics, shape-memory alloys and synthetic polymers and secondary

Purpose: Meconium aspiration is assumed to be a risk factor for bacterial infection, and patients with meconium aspiration syndrome (MAS) are commonly treated with empiric antibiotics in clinical settings. However, little is known about the effectiveness of the empirical antibiotics treatment. Here, we compared the short-term clinical outcomes associated with empirical antibiotics treatment in non-ventilated cases of MAS. Methods: A retrospective study was conducted on infants admitted with non-ventilated cases of MAS from March 2008 to September 2016. The infants enrolled in the study were divided into two groups based on the antibiotics treatment, and their clinical outcomes were compared. The incidence of sepsis during the hospitalization period and the incidence of delayed sepsis up to 3 months were evaluated. The effects of empirical antibiotic use on respiratory symptoms were evaluated, and the complications were compared. Results: A total of 109 infants were evaluated, of which 61 (56.0%) received antibiotics and 48 (44.0%) did not receive antibiotics. No differences in clinical characteristics were noted between the two groups. However, the empirical antibiotics group showed a significantly higher mean of respiratory rates, C-reactive protein levels, and positive rates, as well as a significantly longer hospitalization period. In clinical outcomes, there were no differences in sepsis rates or respiratory support duration. Furthermore, there were no differences in complications. Conclusion: The empirical use of antibiotics did not affect the clinical outcomes in cases of non-ventilated MAS. The role of empirical antibiotics in these infants may need to be reevaluated. [ABSTRACT FROM AUTHOR]

Background/Aims: The functional relevance of early growth response-1 (EGR1) on cancer invasion remains controversial. The effect of EGR1 on the expression of MMP9, which is important for HNSCC invasion, is still disputed. There is no previous data showing the effect of EGR1 on mouse double minute 2 (MDM2), an enhancer of matrix metalloproteinase 9 (MMP9) expression. Our aim is to clarify the negative correlation between EGR1 expression and head and neck squamous cell carcinoma (HNSCC) metastasis. Methods: EGR1 mRNA and protein expressions were compared in normal and HNSCC tissues using The Cancer Genome Atlas (TCGA) dataset analysis or immunohistochemistry (IHC), respectively. In vitro cell invasion was evaluated Matrigel invasion assay. EGR1-dependent inhibition of MDM2 transcription was assessed by promoter--luciferase assay and chromatin immunoprecipitation (ChIP). Results: TCGA data showed that EGR1 mRNA levels are significantly higher in normal oral tissues as compared with HNSCC tumor tissues (adjusted P = 1.64x10-16). In addition, nonmetastatic HNSCC tissues showed significantly higher EGR1 mRNA levels as compared with metastatic tissues (adjusted P = 0.023). IHC analysis showed that primary tumor tissues expressed significantly higher levels of nuclear EGR1 compared with paired metastatic lymph node tissues (P < 0.05). EGR1 overexpression downregulated MMP9 and MDM2 protein expression. Consistent with these observations, TCGA data analysis found significantly fewer metastatic patients among a subgroup of population presenting higher EGR1 expressions with lower MMP9 and/or MDM2. Conclusion: Our data suggests that EGR1 prevents HNSCC metastasis through downregulation of MMP9 and MDM2. EGR1 might be a potential candidate to attenuate HNSCC metastasis. [ABSTRACT FROM AUTHOR]

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis, which triggers severe pulmonary diseases. Recently, multidrug/extensively drug-resistant tuberculosis strains have emerged and continue to threaten global health. Because of the development of drug-resistant tuberculosis, there is an urgent need for novel antibiotics to treat these drug-resistant bacteria. In light of the clinical importance of M. tuberculosis, 2067 structures of M. tuberculsosis proteins have been determined. Among them, 52 structures have been solved and studied using solution nuclear magnetic resonance (NMR). The functional details based on structural analysis of M. tuberculosis using NMR can provide essential biochemical data for the development of novel antibiotic drugs. In this review, we introduce diverse structural and biochemical studies on M. tuberculosis proteins determined using NMR spectroscopy. [ABSTRACT FROM AUTHOR]

The surface coating of solid substrates using dextrans has gained a great deal of attention, because dextran-coated surfaces show excellent anti-fouling property as well as biocompatibility behavior. Much effort has been made to develop efficient methods for grafting dextrans on solid surfaces. This led to the development of catechol-conjugated dextrans (Dex-C) which can adhere to a number of solid surfaces, inspired by the underwater adhesion behavior of marine mussels. The present study is a systematic investigation of the characteristics of surface coatings developed with Dex-C. Various Dex-C with different catechol contents were synthesized and used as a surface coating material. The effect of catechol content on surface coating and antiplatelet performance was investigated. [ABSTRACT FROM AUTHOR]

Background: Recently, a Korean research group suggested a consensus protocol, based on the Alzheimer's Disease Neuroimaging Initiative study protocol but with modifications for minimizing the confounding factors, for the evaluation of cerebrospinal fluid (CSF) biomarkers.Objective: Here, we analyzed fluid and imaging biomarkers of Alzheimer's disease (AD) in Korean population. We used the updated protocol to propose a more accurate CSF biomarker value for the diagnosis of AD.Methods: Twenty-seven patients with AD and 30 cognitively normal controls (NC) were enrolled. CSF was collected from 55 subjects (patients with AD = 26, NC = 29) following the Korea consensus protocol. CSF biomarkers were measured using the INNO-BIA AlzBio3 immunoassay, and Pittsburgh compound B (PIB) positron emission tomography (PET) scans were also performed.Results: The cutoff values of CSF amyloid beta 1-42 (Aβ42), total tau (t-Tau), and phosphorylated tau (p-Tau) proteins were 357.1 pg/ml, 83.35 pg/ml, and 38.00 pg/ml, respectively. The cutoff values of CSF t-Tau/Aβ42 and p-Tau/Aβ42 ratio- were 0.210 (sensitivity 100%, specificity 86.21%) and 0.1350 (sensitivity 88.46%, specificity of 92.86%). The concordance rate with PIB-PET was higher using the CSF t-Tau/Aβ42 ratio (κ= 0.849, CI 0.71-0.99) than CSF Aβ42 alone (κ= 0.703, CI 0.51-0.89).Conclusions: Here, we improved controversial factors associated with the previous CSF study protocol and suggested a new cutoff value for the diagnosis of AD. Our results showed good diagnostic performance for differentiation of AD. Thus, we expect our findings could be a cornerstone in the establishment and clinical application of biomarkers for AD diagnosis. [ABSTRACT FROM AUTHOR]

The control of marine biofouling has gained significant attention because the uncontrolled adhesion of marine organisms onto synthetic surfaces leads to serious problems. Here, we demonstrate a facile method to inhibit the adhesion of marine organisms using the sulfated polysaccharide, heparin. Heparin was conjugated with an adhesive molecule, catechol, and the resulting adhesive heparin was used as a surface coating for stainless steel, a material commonly used for marine vessels. Immersion of stainless steel surfaces in a solution of adhesive heparin resulted in a stable heparin coating. The marine antifouling property of the surface was confirmed using marine diatom adhesion assays, which revealed that the adhesive heparin coating reduced diatom adhesion by ~75%, as compared with untreated surfaces. [ABSTRACT FROM AUTHOR]

A simple, rapid, and convenient colorimetric chemosensor of a specific target toward the end user is still required for on-site detection and real-time monitoring applications. In this study, we developed a rapid in situ colorimetric assay for cobalt detection using the naked eye. Interestingly, a yellow to light orange visual color transition was observed within 3 s when a Chrysoidine G (CG) chemosensor was exposed to cobalt. Surprisingly, the CG chemosensor had great selectivity toward cobalt without any interference of other metal ions. Under optimized conditions, a lower detection limit of 0.1 ppm via a spectrophotometer and a visual detection limit of 2 ppm with a linear range from 0.4 to 1 ppm (R2 = 0.97) were determined. Moreover, the CG chemosensor is reversible and maintains its functionality after treatment with chelating agents. In conclusion, we show the superior capabilities of the CG chemosensor, which has the potential to provide extremely facile handling, high sensitivity, and a fast response time for applications of on-site detection to real-time cobalt monitoring for the general public. [ABSTRACT FROM AUTHOR]

Most agricultural traits are controlled by quantitative trait loci (QTLs); however, there are fewstudies on QTLmapping of horticultural traits in pepper (Capsicumspp.) due to the lack of high-densitymolecular maps and the sequence information. In this study, an ultra-high-density map and 120 recombinant inbred lines (RILs) derived from a cross between C. annuum 'Perennial' and C. annuum 'Dempsey' were used for QTL mapping of horticultural traits. Parental lines and RILs were resequenced at 18× and 1× coverage, respectively. Using a sliding window approach, an ultra-high-density bin map containing 2,578 bins was constructed. The total map length of the map was 1,372 cM, and the average interval between binswas 0.53 cM. A total of 86 significant QTLs controlling 17 horticultural traitswere detected. Among these, 32 QTLs controlling 13 traits were major QTLs. Our research shows that the construction of bin maps using low-coverage sequence is a powerful method for QTL mapping, and that the short intervals between bins are helpful for fine-mapping of QTLs. Furthermore, bin maps can be used to improve the quality of reference genomes by elucidating the genetic order of unordered regions and anchoring unassigned scaffolds to linkage groups. [ABSTRACT FROM AUTHOR]

Free-standing thin nanoplates of Bi2Te3 and Bi2Se3 were synthesized by solvothermal method. It was demonstrated that the thickness of the nanoplates can be controlled by introducing a controlled amount of polyvinylpyrrolidone (PVP) in the synthesis reaction. PVP bonds to the polar basal planes of hexagonal crystal structure of Bi2Te3 and Bi2Se3, and they suppress the growth (speed) of the hexagonal crystals in the c-axis direction. Highly anisotropic growth yielded the formation of 2-dimensional nanostructures of nanoplates. The plates were examined directly with transmission electron microscopy (TEM) with in-situ heating. These crystalline nanoplates with extremely high width to thickness ratios were found to exhibit much lower thermal stability compared to the bulk counterpart or the conventional nanoparticles as represented by the reduced melting temperature. The melting temperature of a nanoplate decreased by more than 100° C compared to the melting temperature of the bulk material. While it is widely known that the meting temperature decreases for nanoparticles with reduced sizees in all three spatial dimensions, we demonstrate that the reduction in one dimension, i.e. thickness of the platelets in the present study, is effective enough to induce much greater decrease of the melting point than the decrease as observed for the case of nanoparticles. [ABSTRACT FROM AUTHOR]

Background: Breast metastasis from extramammary malignancy is uncommon and often presents diagnostic challenges. Herein, we report a case of a patient with metachronous isolated breast metastasis from pulmonary adenocarcinoma with micropapillary component. Case presentation: A 47-year-old woman presented with left breast nodule detected on a screening breast ultrasonography. She had surgery for pulmonary adenocarcinoma 3 years ago, and was disease-free state in the follow up studies. The patient was diagnosed with invasive micropapillary carcinoma of the breast by core needle biopsy. She underwent left breast lumpectomy and sentinel lymph node biopsy, and the histologic findings revealed micropapillary carcinoma. Based on the immunohistochemical study, the final diagnosis was solitary breast metastasis from pulmonary adenocarcinoma with micropapillary component. Conclusions: The diagnosis of metastasis to the breast from extramammary malignancies is difficult but important for proper management and prediction of prognosis. A careful clinical history with a thorough clinical examination is needed to make the correct diagnosis. [ABSTRACT FROM AUTHOR]

Intratesticular cysts, once thought to be a rarity, are now being reported with an increasing prevalence as a result of the wider use of scrotal ultrasound scanning. Despite greater understanding of intratesticular cysts, their management remains unclear. Treatment has included enucleation and even radical orchiectomy over fear of the possibility of an associated malignancy. A more conservative approach with serial ultrasound scanning has been advocated if a clear distinction can be made between neoplastic and non-neoplastic testicular cysts. However, in view of the benign nature of such cysts, even repeated ultrasound scanning may not be necessary and may be considered over-treatment. In this study we present clinical and morphological characteristics of multiple cysts in the right testicle in a 62-year-old patient, where a slightly nodular lesion in the right testicle was detected. [ABSTRACT FROM AUTHOR]

The article provides information on a study which analyzed the iron (Fe)(III)/polydopamine (pDA)-mediated capture and release of catecholic compounds using a method developed from mussel byssus cuticle. Topics discussed include the capture and release of pyrocatechol violet (PCV), use of ethylenediaminetetraacetic acid (EDTA) treatment to demonstrate the release of captured PCV, and pDA coating on silica beads.

Binding behaviors of streptavidin were investigated with different lateral packing densities of biotin-functionalized, non-biofouling pOEGMA brushes, synthesized by surface-initiated polymerization from mixed SAMs with different mole fractions of the polymerization initiator on gold surfaces. [ABSTRACT FROM AUTHOR]

The individual encapsulation of living cells has a great impact on the area of cell-based sensors and devices as well as fundamental studies in cell biology. In this work, living yeast cells were individually encapsulated with functionalizable, artificial polydopamine shells, inspired by an adhesive protein in mussels. Yeast cells maintained their viability within polydopamine, and the cell cycle was controlled by the thickness of the shells. In addition, the artificial shells aided the cell in offering much stronger resistance against foreign aggression, such as lyticase. After formation of the polydopamine shells, the shells were functionalized with streptavidin by utilizing the chemical reactivity of polydopamine, and the fun ctionalized cells were biospecifically immobilized onto the defined surfaces. Our work suggests a biomimetic approach to the encapsulation and functionalization of individual living cells with covalently bonded, artificial shells. [ABSTRACT FROM AUTHOR]

Abstract Clinical outcome after traumatic brain injury (TBI) is closely associated conditions of other organs, especially lungs as well as degree of brain injury. Even if there is no direct lung damage, severe brain injury can enhance sympathetic tones on blood vessels and vascular resistance, resulting in neurogenic pulmonary edema. Conversely, lung damage can worsen brain damage by dysregulating immunity. These findings suggest the importance of brain-lung axis interactions in TBI. However, little research has been conducted on the topic. An advanced disease model using stem cell technology may be an alternative for investigating the brain and lungs simultaneously but separately, as they can be potential candidates for improving the clinical outcomes of TBI. In this review, we describe the importance of brain-lung axis interactions in TBI by focusing on the concepts and reproducibility of brain and lung organoids in vitro. We also summarize recent research using pluripotent stem cell-derived brain organoids and their preclinical applications in various brain disease conditions and explore how they mimic the brain-lung axis. Reviewing the current status and discussing the limitations and potential perspectives in organoid research may offer a better understanding of pathophysiological interactions between the brain and lung after TBI.

Peptide-based therapeutics have traditionally faced challenges, including instability in the bloodstream and limited cell membrane permeability. However, recent advancements in α-helix stapled peptide modification techniques have rekindled interest in their efficacy. Notably, these developments ensure a highly effective method for improving peptide stability and enhancing cell membrane penetration. Particularly in the realm of antimicrobial peptides (AMPs), the application of stapled peptide techniques has significantly increased peptide stability and has been successfully applied to many peptides. Furthermore, constraining the secondary structure of peptides has also been proven to enhance their biological activity. In this review, the entire process through which hydrocarbon-stapled antimicrobial peptides attain improved drug-like properties is examined. First, the essential secondary structural elements required for their activity as drugs are validated, specific residues are identified using alanine scanning, and stapling techniques are strategically incorporated at precise locations. Additionally, the mechanisms by which these structure-based stapled peptides function as AMPs are explored, providing a comprehensive and engaging discussion.