Hierarchical Self-Assembly of Poly-Pseudorotaxanes into Artificial Microtubules.

Hierarchical self-assembly of building blocks over multiple length scales is ubiquitous in living organisms. Microtubules are one of the principal cellular components formed by hierarchical self-assembly of nanometer-sized tubulin heterodimers into protofilaments, which then associate to form micron-length-scale, multi-stranded tubes. This peculiar biological process is now mimicked with a fully synthetic molecule, which forms a 1:1 host-guest complex with cucurbit[7]uril as a globular building block, and then polymerizes into linear poly-pseudorotaxanes that associate laterally with each other in a self-shape-complementary manner to form a tubular structure with a length over tens of micrometers. Molecular dynamic simulations suggest that the tubular assembly consists of eight poly-pseudorotaxanes that wind together to form a 4.5 nm wide multi-stranded tubule.

A literature review of bioactive substances for the treatment of periodontitis: In vitro, in vivo and clinical studies.

Periodontitis is a common chronic inflammatory disease of the supporting tissues of the tooth that involves a complex interaction of microorganisms and various cell lines around the infected site. To prevent and treat this disease, several options are available, such as scaling, root planning, antibiotic treatment, and dental surgeries, depending on the stage of the disease. However, these treatments can have various side effects, including additional inflammatory responses, chronic wounds, and the need for secondary surgery. Consequently, numerous studies have focused on developing new therapeutic agents for more effective periodontitis treatment. This review explores the latest trends in bioactive substances with therapeutic effects for periodontitis using various search engines. Therefore, this study aimed to suggest effective directions for therapeutic approaches. Additionally, we provide a summary of the current applications and underlying mechanisms of bioactive substances, which can serve as a reference for the development of periodontitis treatments.

Monolayer, open-mesh, pristine PEDOT:PSS-based conformal brain implants for fully MRI-compatible neural interfaces.

Understanding brain function is essential for advancing our comprehension of human cognition, behavior, and neurological disorders. Magnetic resonance imaging (MRI) stands out as a powerful tool for exploring brain function, providing detailed insights into its structure and physiology. Combining MRI technology with electrophysiological recording system can enhance the comprehension of brain functionality through synergistic effects. However, the integration of neural implants with MRI technology presents challenges because of its strong electromagnetic (EM) energy during MRI scans. Therefore, MRI-compatible neural implants should facilitate detailed investigation of neural activities and brain functions in real-time in high resolution, without compromising patient safety and imaging quality. Here, we introduce the fully MRI-compatible monolayer open-mesh pristine PEDOT:PSS neural interface. This approach addresses the challenges encountered while using traditional metal-based electrodes in the MRI environment such as induced heat or imaging artifacts. PEDOT:PSS has a diamagnetic property with low electrical conductivity and negative magnetic susceptibility similar to human tissues. Furthermore, by adopting the optimized open-mesh structure, the induced currents generated by EM energy are significantly diminished, leading to optimized MRI compatibility. Through simulations and experiments, our PEDOT:PSS-based open-mesh electrodes showed improved performance in reducing heat generation and eliminating imaging artifacts in an MRI environment. The electrophysiological recording capability was also validated by measuring the local field potential (LFP) from the somatosensory cortex with an in vivo experiment. The development of neural implants with maximized MRI compatibility indicates the possibility of potential tools for future neural diagnostics.

Plaque removal effectiveness of 3D printed dental hygiene chews with various infill structures through artificial dog teeth.

Pet food has recently been in the spotlight as an auxiliary approach to manage oral health, since it helps dogs or cats to take relatively simple care of their mouths at home. Especially, dental hygiene chew is crucial to remove teeth accumulation or plaque by chemical or mechanical methods. This study applied 3D printing to dental chews, which should be tailored to dogs' individual tooth structure and preferences. The optimum methods for making dental hygiene chews based on corn starch with glycerin for extrusion-based 3D printing were developed. The viscoelasticity of dental chews increased with increasing glycerin content. According to the infill level (40%, 60%, or 80%) and glycerin content, texture and plaque removal efficacy were investigated using a texture analyzer and dog dentures. A 60% infill level with 10% and 20% glycerin content had the best plaque removal efficacy in both canines and premolars. A lattice structure design with square holes was more effective for canines, whereas a crumbly texture was more effective for premolars.

Effect of silicon or cerium doping on the anti-inflammatory activity of biphasic calcium phosphate scaffolds for bone regeneration.

Biphasic calcium phosphate (BCP) bioceramics composed of hydroxyapatite and ß-tricalcium phosphate have attracted considerable attention as ideal bone substitutes for reconstructive surgery, orthopedics, and dentistry, owing to their similar chemical composition to bone mineral and biocompatibility. The addition of trace elements to BCP bioceramics, such as magnesium (Mg), cerium (Ce), and silicon (Si), can alter the physicochemical and biological properties of the resulting materials. To improve the anti-inflammatory activity of a pure BCP scaffold, this study developed a simple wet chemical precipitation and gel-casting method to fabricate microporous BCP scaffolds containing Si or Ce. The BCP scaffolds exhibited interconnected microporous structures with uniform micropores and unequiaxed grains. No changes in the phase composition and microstructure of the scaffolds with the Si or Ce doping were observed. Conversely, Si or Ce doping into the BCP crystal lattice influenced the in vitro biological activity of the scaffolds and the bone-forming ability of the cells cultured on the BCP scaffolds. The results of biological activity assays demonstrated that Ce-BCP promoted cell proliferation and osteogenic differentiation more effectively than the other scaffolds. In particular, Ce-BCP significantly suppressed the expression of bone-active cytokines via the anti-inflammatory and anti-oxidative effects. Therefore, Si- or Ce-doped BCP scaffolds can contribute to providing a new generation of bone graft substitutes.

Development of an Abalone 3D Food Printing Ink for the Personalized Senior-Friendly Foods.

Notably for seniors, 3D food printing is an appropriate processing method for creating customized meals that meet their unique nutritional requirements and textural preferences. This study attempted to develop an ink for food 3D printers containing abalone powder and several nutrition properties that meet the criteria for senior-friendly foods. The texture of the products was adjusted using gelatin. The ink consisted of abalone powder (10%), soybean protein (4.5%), polydextrose (2.5%), vitamin C (0.0098%), and gellan gum (1%). To examine the physicochemical properties of the ink, texture, water holding capacity, and rheological properties were measured. In addition, the suitability of the 3D printing was examined. As a result, 3% gelatin 3D food printing ink demonstrated optimal printability and could be converted into foods that could be consumed in one step (teeth intake), depending on the types of food for seniors.

NONOates--polyethylenimine hydrogel for controlled nitric oxide release and cell proliferation modulation.

In recent years, numerous research activities have been devoted to the controlled release of nitric oxide (NO) due to its potential as a restenosis inhibitor which inhibits the proliferation of vascular smooth muscle cells, the apoptosis of vascular endothelial cells, and aggregation of platelets. This work has demonstrated the development of a novel NO-conjugated gel system comprising of thermosensitive Pluronic F127, branched polyethylenimine (BPEI), and diazeniumdiolates (NONOates). Synthesis of conjugated Pluronic-BPEI-NONOates involved coupling of activated F127 to BPEI followed by the installation of NONOates at the secondary amine sites of branched PEI backbone under high pressure. NO-conjugated gel system, F127-BPEI-NONOates, reduced the initial burst of NO release and prolonged NO release. Furthermore, F127-BPEI-NONOates polymer coated on cell culture dish displayed much higher increase of endothelial cell proliferation and reduction of smooth muscle cell proliferation than that exhibited by non-NO releasing control. Such an NO-releasing device can operate locally and has a great potential in several biomedical applications due to high biocompatibility imparted by the conjugated F127.

Chromosomal assembly of the Antarctic toothfish ( Dissostichus mawsoni) genome using third-generation DNA sequencing and Hi-C technology.

The Antarctic toothfish, Dissostichus mawsoni, belongs to the Nototheniidae family and is distributed in sub-zero temperatures below S60° latitude in the Southern Ocean. Therefore, it is an attractive model species to study the stenothermal cold-adapted character state. In this study, we successfully generated highly contiguous genome sequences of D. mawsoni, which contained 1 062 scaffolds with a N50 length of 36.98 Mb and longest scaffold length of 46.82 Mb. Repetitive elements accounted for 40.87% of the genome. We also inferred 32 914 protein-coding genes using in silico gene prediction and transcriptome sequencing and detected splicing variants using Isoform-Sequencing (Iso-Seq), which will be invaluable resource for further exploration of the adaptation mechanisms of Antarctic toothfish. This new high-quality reference genome of D. mawsoni provides a fundamental resource for a deeper understanding of cold adaptation and conservation of species.

Characterization of the complete mitochondrial genome of Odontobutis platycephala collected from Nakdong River, South Korea.

The complete mitochondrial genome of Odontobutis platycephala collected from a native Korean river was determined by the bioinformatics assembly of the next-generation sequencing (NGS) reads. The circular mitogenome was 17,590 bp length which harbored canonical 13 protein-coding genes, 22 tRNAs, and 2 rRNAs, which was identical to those of family Odontobutidae. Twenty-eight genes were located on H strand, whereas remaining nine genes were on L strand. Except for COX1 gene (GTG), other 12 protein-coding genes were predicted typical start codons (ATG). Among the currently known mitogenome sequences, O. platycephala showed highest identity (96.98%) to Korean haplotype of O. platycephala (NC010199).

Effect of granular porous media on the composting of swine manure.

This study investigated the feasibility of a bulking agent of granular porous media (GPM) for the composting of swine manure. Two lab-scale composting reactors were operated to evaluate the general performances and maturity parameters using GPM made of wastes from the Portland cement manufacturing processes as an alternative bulking agent. The overall volatile solid (VS) removal was 38.5% (dry basis). During the experiments, moisture content ranged between 41% and 53%, ensuring feasibility of microbial activity in composting. Cured compost showed proper maturity and low phytotoxicity, despite the slight decreases of CO2 production and VS removal at the second batch operation. Various physico-chemical parameters of the cured compost met the regulatory standards reported elsewhere. The pH, carbon-to-nitrogen ratio, ammonia nitrogen and soluble organic carbon (SOC) of the cured compost were significantly correlated to the germination index (GI) using the seeds of Chinese cabbage and lettuce, indicating the progressive biodegradation of phytotoxins as well as organic matter. Consequently, the results obtained in this study demonstrate that GPM could contribute to the environmentally friendly and economical composting of problematic swine manure as a recyclable bulking agent.

Metabarcoding analysis of the stomach contents of the Antarctic Toothfish (Dissostichus mawsoni) collected in the Antarctic Ocean.

Stomach contents of the Antarctic toothfish, Dissostichus mawsoni, collected from subareas 58.4 and 88.3, were analyzed using next generation sequencing (NGS) technology. After processing the raw reads generated by the MiSeq platform, a total of 131,233 contigs (130 operational taxonomic units [OTUs]) were obtained from 163 individuals in subarea 58.4, and 75,961 contigs (105 OTUs) from 164 fish in subarea 88.3. At 98% sequence identity, species names were assigned to most OTUs in this study, indicating the quality of the DNA barcode database for the Antarctic Ocean was sufficient for molecular analysis, especially for fish species. A total of 19 species was identified from the stomach of D. mawsoni in this study, which included 14 fish species and five mollusks. More than 90% of contigs belonged to fish species, supporting the postulate that the major prey of D. mawsoni are fish. Two fish species, Macrourus whitsoni and Chionobathyscus dewitti, were the most important prey items (a finding similar to that of previous studies). We also obtained genotypes of prey items by NGS analysis, identifying an additional 17 representative haplotypes in this study. Comparison with three previous morphological studies and the NGS-based molecular identification in this study extended our knowledge regarding the prey of D. mawsoni, which previously was not possible. These results suggested that NGS-based diet studies are possible, if several current technical limitations, including the quality of the barcode database or the development of precise molecular quantification techniques to link them with morphological values, are overcome. To achieve this, additional studies should be conducted on various marine organisms.

Initial Use of High-Dose Anticholinergics Combined with Alpha-Blockers for Male Lower Urinary Tract Symptoms with Overactive Bladder: A Prospective, Randomized Preliminary Study.

OBJECTIVES: To evaluate the clinical efficacy of initial combined treatment of alpha-blocker plus dose-dependent anticholinergic agent compared to the alpha-blocker monotherapy in benign prostatic hyperplasia patients with overactive bladder. METHODS: Male lower urinary tract symptoms (LUTS) patients with International Prostate Symptom Score (IPSS) of 8 or higher, total overactive bladder Symptom Score (OABSS) of 3 or higher, and 2 points or higher in the OABSS questionnaire number 2 were enrolled. Eligible subjects (total n = 146) were randomly assigned to receive tamsulosin 0.2 mg (Group I, n = 44), tamsulosin 0.2 mg plus solifenacin 5 mg (Group II, n = 55), or tamsulosin 0.2 mg plus solifenacin 10 mg (Group III, n = 47) for 12 weeks. Efficacy and safety assessments for each group were done using detailed questionnaires, and evaluating urinary parameters such as maximal urinary flow rate (Qmax) and postvoid residual volume (PVR) at 4 and 12 weeks. RESULTS: Groups II and III (combined use of tamsulosin and solifenacin) showed significant improvement in storage symptoms compared to group I (tamsulosin monotherapy), as reflected by IPSS storage subscore and OABSS (P < 0.05). Dry mouth developed in four (7%) and eight (17%) cases in group II and III, respectively, so that one (2%) and three (6%) cases dropped out in group II and III, respectively. Two cases (4%) of AUR developed in group III, and one of them was withdrawn (2%) from the study. CONCLUSIONS: Initial combined treatment of tamsulosin plus solifenacin for men with LUTS improves storage symptoms significantly, but dose modification is necessary to prevent adverse events.

Toxicity and tissue distribution of magnetic nanoparticles in mice.

The development of technology enables the reduction of material size in science. The use of particle reduction in size from micro to nanoscale not only provides benefits to diverse scientific fields but also poses potential risks to humans and the environment. For the successful application of nanomaterials in bioscience, it is essential to understand the biological fate and potential toxicity of nanoparticles. The aim of this study was to evaluate the biological distribution as well as the potential toxicity of magnetic nanoparticles to enable their diverse applications in life science, such as drug development, protein detection, and gene delivery. We recently synthesized biocompatible silica-overcoated magnetic nanoparticles containing rhodamine B isothiocyanate (RITC) within a silica shell of controllable thickness [MNPs@SiO2(RITC)]. In this study, the MNPs@SiO2(RITC) with 50-nm thickness were used as a model nanomaterial. After intraperitoneal administration of MNPs@SiO2(RITC) for 4 weeks into mice, the nanoparticles were detected in the brain, indicating that such nanosized materials can penetrate blood-brain barrier (BBB) without disturbing its function or producing apparent toxicity. After a 4-week observation, MNPs@SiO2(RITC) was still present in various organs without causing apparent toxicity. Taken together, our results demonstrated that magnetic nanoparticles of 50-nm size did not cause apparent toxicity under the experimental conditions of this study.

Regulation of transduction efficiency by pegylation of baculovirus vector in vitro and in vivo.

In this study, poly(ethylene glycol) (PEG) was coupled to baculovirus to regulate transduction efficiency of baculovirus in vitro and in vivo. The degree of pegylation in virions was measured by the loss of free amines via a fluorescamine-based assay. The efficiency of green fluorescent protein (GFP) expression was used to monitor transduction efficiency. As the results, the transduction efficiency in pegylated baculovirus was decreased with an increase of pegylation in baculovirus in vitro and in vivo. Interestingly, the transduction efficiency of the pegylated baculovirus for the lung and brain was increased compared with baculovirus itself possibly owing to increased stability of baculovirus by pegylation.

Aerosol delivery of glucosylated polyethylenimine/phosphatase and tensin homologue deleted on chromosome 10 complex suppresses Akt downstream pathways in the lung of K-ras null mice.

Difficulties in achieving long-term survival of lung cancer patients treated with conventional therapies suggest that novel approaches are required. Although several genes have been investigated for antitumor activities using gene delivery, problems surrounding the methods used such as efficiency, specificity, and toxicity hinder its application as an effective therapy. This has lead to the re-emergence of aerosol gene delivery as a noninvasive approach to lung cancer therapy. In this study, glucosylated conjugated polyethylenimine (glucosylated PEI) was used as carrier. After confirming the efficiency of glucosylated PEI carriers in lungs, the potential effects of the phosphatase and tensin homologue deleted on chromosome 10 (PTEN) tumor suppressor gene on Akt downstream pathways were investigated. Aerosol containing glucosylated PEI and recombinant plasmid pcDNA3.0-PTEN complex was delivered into K-ras null lung cancer model mice through a nose-only inhalation system. Investigation of proteins in the phosphatidylinositol 3'-kinase/Akt signaling pathway in PTEN-delivered mouse lung revealed that the PTEN protein was highly expressed, whereas the protein levels of PDK1, total Akt1, phospho-(Thr-308)-Akt, phospho-(Ser-2448)-mTOR, p70S6K, and 4E-BP1 were decreased to varying degrees. Additionally, the kinase activities of both Akt and mTOR were suppressed. Finally, apoptosis was detected in PTEN-delivered mouse lung by terminal deoxynucleotidyltransferase-mediated nick end labeling assay, suggesting that our aerosol PTEN delivery is capable of functionally altering cell phenotype in vivo. In summary, Western blot analysis, kinase assays, immunohistochemistry, and terminal deoxynucleotidyltransferase-mediated nick end labeling assays suggest that our aerosol gene delivery technique is compatible with in vivo gene delivery and can be applied as a noninvasive gene therapy.

Glucosylated polyethylenimine as a tumor-targeting gene carrier.

Glucosylated polyethylenimine (GPEI) was synthesized as a tumor-targeting gene carrier through facilitative glucose metabolism by tumor glucose transporter. Particle sizes of GPEI/DNA complex increased in proportion to glucose content of GPEI, whereas surface charge of the complex was not dependent on glucosylation, partially due to inefficient shielding of the short hydrophilic group introduced. GPEI with higher glucosylation (36 mol-%) had no cytotoxic effect on cells even at polymer concentrations higher than 200 microg/mL. Compared to unglucosylated PEI, glucosylation induced less than one-order decrease of transfection efficiency. Transfection of GPEI/DNA complex into tumor cells possibly occurred through specific interaction between glucose-related cell receptors and glucose moiety of GPEI. Gamma imaging technique revealed GPEI/DNA complex was distributed in liver, spleen, and tumors.

Core-Corona Functionalization of Diblock Copolymer Micelles by Heterogeneous Metal Nanoparticles for Dual Modality in Chemical Reactions.

Nanoscale assemblies composed of different types of nanoparticles (NPs) can reveal interesting aspects about material properties beyond the functions of individual constituent NPs. This research direction may also represent current challenges in nanoscience toward practical applications. With respect to the assembling method, synthetic or biological nanostructures can be utilized to organize heterogeneous NPs in specific sites via chemical or physical interactions. However, those assembling methods often encounter uncontrollable particle aggregation or phase separation. In this study, we anticipated that the self-segregating properties of block copolymer micelles could be particularly useful for organizing heterogeneous NPs, because the presence of chemically distinct domains such as the core and the corona can facilitate the selective placement of constituent NPs in separate domains. Here, we simultaneously functionalized the core and the corona of micelles by Au NPs and Ag NPs, which exhibited plasmonic and catalytic functions, respectively. Our primary question is whether these plasmonic and catalytic functions can be combined in the assembled structures to engineer the kinetics of a model chemical reaction. To test this hypothesis, the catalytic reduction of 4-nitrophenol was selected to evaluate the collective properties of the micellar assemblies in a chemical reaction.

Sustained release of ascorbate-2-phosphate and dexamethasone from porous PLGA scaffolds for bone tissue engineering using mesenchymal stem cells.

The purpose of this research was to develop porous poly(D,L-lactide-co-glycolide) (PLGA) scaffolds from which ascorbate-2-phosphate (AsAP) and dexamethasone (Dex) are continuously released for a month for osteogenesis of mesenchymal stem cells for bone tissue engineering. Porous PLGA matrices containing AsAP and Dex were prepared by solvent casting/particulate leaching method. In vitro release and water uptake studies were performed in Dulbecco's phosphate buffered saline at 37 degrees C and 15 rpm. Drug loading and release rates were determined by high performance liquid chromatography. Release studies of Dex and AsAP showed that, after an initial burst release lasting 4 and 9 days, respectively, release rates followed zero order kinetics with high correlation coefficients at least until 35 days. Incorporation of AsAP into the scaffolds increased the release rates of Dex and AsAP, and the scaffold water uptake. When mesenchymal stem cells (MSCs) were cultured in the AsAP and Dex containing scaffolds in vitro, the amount of mineralization was significantly higher than in control scaffolds. In conclusion, AsAP and Dex were incorporated into porous PLGA scaffolds and continuously released over a month and osteogenesis of MSCs was increased by culture in these scaffolds.

All-trans-retinoic acid release from core-shell type nanoparticles of poly(epsilon-caprolactone)/poly(ethylene glycol) diblock copolymer.

Poly(epsilon-caprolactone)/poly(ethylene glycol) (abbreviated as CE) diblock copolymers were synthesized to make core-shell type nanoparticles for all-trans-retinoic acid (atRA). Fluorescence spectroscopy showed that critical association concentration (CAC) value decreased at higher MW of CE diblock copolymer. Drug loading characteristics were studied under various experimental conditions. Drug contents and loading efficiency increased as the MW of poly(epsilon-caprolactone) (PCL) block of CE and initial drug feeding amount increased. Solvent used and preparation method also affected drug contents and loading efficiency. According to 1H NMR using CDCl3 and D2O, specific peaks of the PCL block and drug appearing in CDCl3, disappeared at D2O, suggesting hydrophobic core with hydrophilic shell formed in water. atRA release was faster at smaller MW of copolymer and lower drug contents. Nanoparticles prepared in DMF showed faster release rate compared with those prepared in THF or acetone. Cytotoxicity of atRA against U87MG, U251MG and U343MG cell lines were increased by nanoencapsulation while empty nanoparticles of CE diblock copolymer were not significantly affected.

Complications in endoscopic-assisted open reduction and internal fixation of mandibular condyle fractures.

Endoscopic-assisted open reduction and internal fixation (EAORIF) of subcondylar fractures is minimally invasive, provides excellent visibility without a large incision, and reduces surgical scarring and the risk of facial nerve injury. This study evaluated the complications associated with EAORIF. Twenty-six patients underwent EAORIF for mandibular condyle fractures. The postoperative follow-up period was longer than 6 months. We analyzed associations between the complication incidence and the number of fixation plates, accompanying mandibular fractures, and age. Eighteen (69.2%) and 6 (23.1%) patients had temporary (<3 months after surgery) and long-term (>6 months after surgery) complications, respectively. Patients older than 30 years had complications more frequently than those younger than 30 years. Complication rates were similar for different numbers of fixation plates and among patients with and without accompanying mandibular fractures. EAORIF is a reliable technique for treating condylar fractures, regardless of patient age, number of fixation plates, or accompanying mandibular fractures. However, improvements are needed to reduce long-term complications.