A bioengineered skeletal muscle construct that mimics structural and functional characteristics of native skeletal muscle is a promising therapeutic option to treat extensive muscle defect injuries. ...We previously showed that bioprinted human skeletal muscle constructs were able to form multi-layered bundles with aligned myofibers. In this study, we investigate the effects of neural cell integration into the bioprinted skeletal muscle construct to accelerate functional muscle regeneration in vivo. Neural input into this bioprinted skeletal muscle construct shows the improvement of myofiber formation, long-term survival, and neuromuscular junction formation in vitro. More importantly, the bioprinted constructs with neural cell integration facilitate rapid innervation and mature into organized muscle tissue that restores normal muscle weight and function in a rodent model of muscle defect injury. These results suggest that the 3D bioprinted human neural-skeletal muscle constructs can be rapidly integrated with the host neural network, resulting in accelerated muscle function restoration.
Lactic acid bacteria (LAB) are significant groups of probiotic organisms in fermented food and are generally considered safe. LAB regulate soil organic matter and the biochemical cycle, detoxify ...hazardous chemicals, and enhance plant health. They are found in decomposing plants, traditional fermented milk products, and normal human gastrointestinal and vaginal flora. Exploring LAB identified in unknown niches may lead to isolating unique species. However, their classification is quite complex, and they are adapted to high sugar concentrations and acidic environments. LAB strains are considered promising candidates for sustainable agriculture, and they promote soil health and fertility. Therefore, they have received much attention regarding sustainable agriculture. LAB metabolites promote plant growth and stimulate shoot and root growth. As fertilizers, LAB can promote biodegradation, accelerate the soil organic content, and produce organic acid and bacteriocin metabolites. However, LAB show an antagonistic effect against phytopathogens, inhibiting fungal and bacterial populations in the rhizosphere and phyllosphere. Several studies have proposed the LAB bioremediation efficiency and detoxification of heavy metals and mycotoxins. However, LAB genetic manipulation and metabolic engineered tools provide efficient cell factories tailor-made to produce beneficial industrial and agro-products. This review discusses lactic acid bacteria advantages and limitations in sustainable agricultural development.
A bioengineered skeletal muscle tissue as an alternative for autologous tissue flaps, which mimics the structural and functional characteristics of the native tissue, is needed for reconstructive ...surgery. Rapid progress in the cell-based tissue engineering principle has enabled in vitro creation of cellularized muscle-like constructs; however, the current fabrication methods are still limited to build a three-dimensional (3D) muscle construct with a highly viable, organized cellular structure with the potential for a future human trial. Here, we applied 3D bioprinting strategy to fabricate an implantable, bioengineered skeletal muscle tissue composed of human primary muscle progenitor cells (hMPCs). The bioprinted skeletal muscle tissue showed a highly organized multi-layered muscle bundle made by viable, densely packed, and aligned myofiber-like structures. Our in vivo study presented that the bioprinted muscle constructs reached 82% of functional recovery in a rodent model of tibialis anterior (TA) muscle defect at 8 weeks of post-implantation. In addition, histological and immunohistological examinations indicated that the bioprinted muscle constructs were well integrated with host vascular and neural networks. We demonstrated the potential of the use of the 3D bioprinted skeletal muscle with a spatially organized structure that can reconstruct the extensive muscle defects.
The diamond–graphite hybrid thin film with low‐dimensional nanostructure (e.g., nitrogen‐included ultrananocrystalline diamond (N‐UNCD) or the alike), has been employed in many impactful breakthrough ...applications. However, the detailed picture behind the bottom–up evolution of such intriguing carbon nanostructure is far from clarified yet. Here, the authors clarify it, through the concerted efforts of microscopic, physical, and electrochemical analyses for a series of samples synthesized by hot‐filament chemical vapor deposition using methane–hydrogen precursor gas, based on the hydrogen‐dependent surface reconstruction of nanodiamond and on the substrate‐temperature‐dependent variation of the growth species (atomic hydrogen and methyl radical) concentration near substrate. The clarified picture provides insights for a drastic enhancement in the electrochemical activities of the hybrid thin film, concerning the detection of important biomolecule, that is, ascorbic acid, uric acid, and dopamine: their limits of detections are 490, 35, and 25 nm, respectively, which are among the best of the all‐carbon thin film electrodes in the literature. This work also enables a simple and effective way of strongly enhancing AA detection.
The authors clarify the nucleation/growth mechanism of diamond–graphite hybrid thin film with 2D nanostructure (the only successful diamond probe material for neural recording/stimulation), based on nanodiamond surface reconstruction controlled by growth species variation in growth environment. It provides insights for the drastic enhancement of the structure‐optimized thin film performance in simultaneous electrochemical detection of dopamine, ascorbic acid, and uric acid.
The endoplasmic reticulum (ER) is a dynamic organelle that synthesizes and folds proteins. An imbalance between the ER protein synthesis load and its folding capacity triggers the unfolded protein ...response, thereby restoring normal ER functions via size adjustment. Inspired by such inherent genetic programming events, we engineered Saccharomyces cerevisiae to expand the ER by overexpressing a key ER size regulatory factor, INO2. ER space expansion enhanced ER protein synthesis and folding capacity, and relieved metabolic constraints imposed by the limited enzyme abundance. Harnessing the yeast ER for metabolic engineering, we ultimately increased the production of squalene and cytochrome P450-mediated protopanaxadiol by 71-fold and 8-fold, compared to their respective control strains without overexpression of INO2. Furthermore, genome-wide transcriptome analysis of the ER-expanded strain revealed that the significant improvement in terpene production was associated with global rewiring of the metabolic network. Therefore, the yeast ER can be engineered as a specialized compartment for enhancing terpene production, representing new possibilities for the high-level production of other value-added chemicals.
•This study aims to harness yeast endoplasmic reticulum (ER) for functional assembly of challenging metabolic pathways.•ER expansion can lead to increased abundance of ER-associated enzymes and consequential improvement in metabolic capacity.•ER expansion increased production of squalene and cytochrome P450-mediated protopanaxadiol by 71- and 8-fold, respectively.•The squalene titer of 634 mg/L was achieved by shake flask fermentation, the highest titer reported to date in S. cerevisiae.•RNA-seq analysis provides novel frameworks for designing genetic network to construct a platform cell for terpene synthesis.
Metabolites are often unable to permeate cell membranes and are thus accumulated inside cells. We investigate whether engineered microbes can exclusively secrete intracellular metabolites because ...sustainable metabolite secretion holds a great potential for mass-production of high-value chemicals in an efficient and continuous manner. In this study, we demonstrate a synthetic pathway for a metabolite trafficking system that enables lipophilic terpene secretion by yeast cells. When metabolite-binding proteins are tagged with signal peptides, metabolite trafficking is highly achievable; loaded metabolites can be precisely delivered to a desired location within or outside the cell. As a proof of concept, we systematically couple a terpene-binding protein with an export signal peptide and subsequently demonstrate efficient, yet selective terpene secretion by yeast (~225 mg/L for squalene and ~1.6 mg/L for β-carotene). Other carrier proteins can also be readily fused with desired signal peptides, thereby tailoring different metabolite trafficking pathways in different microbes. To the best of our knowledge, this is the most efficient cognate pathway for metabolite secretion by microorganisms.
In South Korea, a November 2021 outbreak caused by severe acute respiratory syndrome coronavirus 2 Omicron variant originated from 1 person with an imported case and spread to households, ...kindergartens, workplaces, restaurants, and hospitals, resulting in 11 clusters within 3 weeks. An epidemiologic curve indicated rapid community transmission of the Omicron variant.
Despite continued efforts using chemical similarity methods in virtual screening, currently developed approaches suffer from time-consuming multistep procedures and low success rates. We recently ...developed a machine learning-based chemical binding similarity model considering common structural features from molecules binding to the same, or evolutionarily related targets. The chemical binding similarity measures the resemblance of chemical compounds in terms of binding site similarity to better describe functional similarities that arise from target binding. In this study, we have shown how the chemical binding similarity could be used in virtual screening together with the conventional structure-based methods. The chemical binding similarity, receptor-based pharmacophore, chemical structure similarity, and molecular docking methods were evaluated to identify an effective virtual screening procedure for desired target proteins. When we tested the chemical binding similarity method with test sets of 51 kinases, it outperformed the traditional structural similarity-based methods as well as structure-based methods, such as molecular docking and receptor-based pharmacophore modeling, in terms of finding active compounds. We further validated the results by performing virtual screening (using the chemical binding similarity and receptor-based pharmacophore methods) against a completely blind dataset for mitogen-activated protein kinase kinase 1 (MEK1), ephrin type-B receptor 4 (EPHB4) and wee1-like protein kinase (WEE1). The in vitro kinase binding assay confirmed that 6 out of 13 (46.2%) for MEK1 and 2 out of 12 (16.7%) for EPHB4 were newly identified only by the chemical binding similarity model. We report that the virtual screening results could further be improved by combining the chemical binding similarity model with 3D-QSAR pharmacophore and molecular docking models. Not only the new inhibitors are identified in this study, but also many of the identified molecules have low structural similarity scores against already reported inhibitors and that show the revelation of novel scaffolds.
The purpose of this article is to evaluate and compare the safety and efficacy of endovascular management of the portal vein (PV) via percutaneous transsplenic access versus percutaneous transhepatic ...access in liver transplantation (LT) recipients. A total of 18 patients who underwent endovascular management of PV via percutaneous transhepatic (n = 8) and transsplenic (n = 10) access were enrolled. Transsplenic access was chosen if the spleen was located in a normal position, the splenic vein (SpV) was preserved, and the target lesion did not involve confluence of the superior mesenteric and SpVs. Accessibility of the percutaneous transsplenic puncture was confirmed via ultrasound (US) in the angiography suite. All procedures were performed under local anesthesia. Percutaneous transhepatic or transsplenic access was performed using a 21‐gauge Chiba needle under US and fluoroscopic guidance, followed by balloon angioplasty, stent placement, or variceal embolization. The access tract was embolized using coils and a mixture (1:2) of glue and ethiodized oil. Transhepatic or transsplenic access was successfully achieved in all patients. A total of 12 patients underwent stent placement; 3 had balloon angioplasty only; 2 had variceal embolization only; and 1 had variceal embolization followed by successful stent placement. Regarding major complications, 1 patient experienced a SpV tear with extravasation during transsplenic balloon angioplasty, which was successfully managed using temporary balloon inflation, followed by transfusion. Clinical success was achieved in 9 of 11 (82%) patients who exhibited clinical manifestations. The remaining 7 patients who underwent prophylactic endovascular management were healthy. In conclusion, endovascular management of PV via percutaneous transsplenic access is a relatively safe and effective alternative that does not damage the liver grafts of LT recipients. Liver Transplantation 23 1133–1142 2017 AASLD.
To determine optimal quarantine duration, we evaluated time from exposure to diagnosis for 107 close contacts of severe acute respiratory syndrome coronavirus 2 Omicron variant case-patients. Average ...time from exposure to diagnosis was 3.7 days; 70% of diagnoses were made on day 5 and 99.1% by day 10, suggesting 10-day quarantine.
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