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Crouch Forsyth posted an update 1 year, 6 months ago
Since the piezoelectric quality of bone was discovered in 1957, scientists have applied exogenous electrical stimulation for the purpose of healing. Despite the efforts made over the past 60 years, electronic bone growth stimulators are not in common clinical use. Reasons for this include high cost and lack of faith in the efficacy of bone growth stimulators on behalf of clinicians. The purpose of this narrative review is to examine the preclinical body of literature supporting electrical stimulation and its effect on bone properties and elucidate gaps in clinical translation with an emphasis on device specifications and mechanisms of action. When examining these studies, trends become apparent. In vitro and small animal studies are successful in inducing osteogenesis with all electrical stimulation modalities direct current, pulsed electromagnetic field, and capacitive coupling. However, large animal studies are largely unsuccessful with the non-invasive modalities. This may be due to issues of scale and thickness of tissue planes with varying levels of resistivity, not present in small animal models. Additionally, it is difficult to draw conclusions from studies due to the varying units of stimulation strength and stimulation protocols and incomplete device specification reporting. To better understand the disconnect between the large and small animal model, the authors recommend increasing scientific rigor for these studies and reporting a novel minimum set of parameters depending on the stimulation modality.Total hip arthroplasty (THA) is an extremely successful treatment strategy. Patient expectations, however, have increased; if not properly guided by surgeons, at present, patients expect next to pain-free restoration of the joint and a fast return to work and sports. While the revision rates after THA also increased in younger patients, knowledge on musculoskeletal loads still remains sparse, and the current recommendations on postoperative rehabilitation are based on expert opinions only. The aim of this study was to unravel biomechanical contact conditions in “working age” (60 years, 67.7 ± 8.6 years) patients during activities recommended post-THA. We hypothesized that working age patients would show substantially increased hip contact loads compared to older patients. The in vivo joint contact force (F res) and torsion torque (M tors), reflecting the main contact load situation, experienced during activities of daily living and sports activities were measured in a unique group of 16 patients with instrumeated hereby. The findings from this work illustrate the need to provide critical feedback to patient expectations when returning to work and sports activities. Patients returning to more intensive sports activities should be carefully monitored and advised to avoid as much overloading as possible.Three-dimensional (3D)-printed in vitro tissue models have been used in various biomedical fields owing to numerous advantages such as enhancements in cell response and functionality. In liver tissue engineering, several studies have been reported using 3D-printed liver tissue models with improved cellular responses and functions in drug screening, liver disease, and liver regenerative medicine. However, the application of conventional single-component bioinks for the printing of 3D in vitro liver constructs remains problematic because of the complex structural and physiological characteristics of the liver. The use of multicomponent bioinks has become an attractive strategy for bioprinting 3D functional in vitro liver tissue models because of the various advantages of multicomponent bioinks, such as improved mechanical properties of the printed tissue construct and cell functionality. MLN8054 manufacturer Therefore, it is essential to review various 3D bioprinting techniques and multicomponent hydrogel bioinks proposed for liver tissue engineering to suggest future directions for liver tissue engineering. Accordingly, we herein review multicomponent bioinks for 3D-bioprinted liver tissues. We first describe the fabrication methods capable of printing multicomponent bioinks and introduce considerations for bioprinting. We subsequently categorize and evaluate the materials typically utilized for multicomponent bioinks based on their characteristics. In addition, we also review recent studies for the application of multicomponent bioinks to fabricate in vitro liver tissue models. Finally, we discuss the limitations of current studies and emphasize aspects that must be resolved to enhance the future applicability of such bioinks.Preparation of the Magnéli Ti4O7 reactive electrochemical membrane (REM) with high purity is of great significance for its application in electrochemical advanced oxidation processes (EAOPs) for wastewater treatment. In this study, the Ti4O7 REM with high purity was synthesized by mechanical pressing of TiO2 powders followed by thermal reduction to Ti4O7 using the Ti powder as the reducing reagent, where the TiO2 monolith and Ti powder were separated from each other with the distance of about 5 cm in the vacuum furnace. When the temperature was elevated to 1333 K, the Magnéli phase Ti4O7 REM with the Ti4O7 content of 98.5% was obtained after thermal reduction for 4 h. Noticeably, the surface and interior of the obtained REM bulk sample has a homogeneous Ti4O7 content. Doping carbon black (0wt%-15wt%) could increase the porosity of the Ti4O7 REM (38-59%). Accordingly, the internal resistance of the electrode and electrolyte and the charge-transfer impedance increased slightly with the increasing carbon black content. The optimum electroactive surface area (1.1 m2) was obtained at a carbon black content of 5wt%, which increased by 1.3-fold in comparison with that without carbon black. The as-prepared Ti4O7 REMs show high oxygen evolution potential, approximately 2.7 V/SHE, indicating their appreciable electrocatalytic activity toward the production of •OH.Cells employ post-translational modifications (PTMs) as key mechanisms to expand proteome diversity beyond the inherent limitations of a concise genome. The ability to incorporate post-translationally modified amino acids into protein targets via chemical ligation of peptide fragments has enabled the access to homogeneous proteins bearing discrete PTM patterns and empowered functional elucidation of individual modification sites. Native chemical ligation (NCL) represents a powerful and robust means for convergent assembly of two homogeneous, unprotected peptides bearing an N-terminal cysteine residue and a C-terminal thioester, respectively. The subsequent discovery that protein cysteine residues can be chemoselectively desulfurized to alanine has ignited tremendous interest in preparing unnatural thiol-derived variants of proteogenic amino acids for chemical protein synthesis following the ligation-desulfurization logic. Recently, the 21st amino acid selenocysteine, together with other selenyl derivatives of amino acids, have been shown to facilitate ultrafast ligation with peptidyl selenoesters, while the advancement in deselenization chemistry has provided reliable bio-orthogonality to PTMs and other amino acids. The combination of these ligation techniques and desulfurization/deselenization chemistries has led to streamlined synthesis of multiple structurally-complex, post-translationally modified proteins. In this review, we aim to summarize the latest chemical synthesis of thiolated and selenylated amino-acid building blocks and exemplify their important roles in conquering challenging protein targets with distinct PTM patterns.Three new polyketide dimers named huoshanmycins A‒C (1-3) were isolated from a plant endophytic Streptomyces sp. HS-3-L-1 in the leaf of Dendrobium huoshanense, which was collected from the Cultivation base in Jiuxianzun Huoshanshihu Co., Ltd. The dimeric structures of huoshanmycins were composed of unusual polyketides SEK43, SEK15, or UWM4, with a unique methylene linkage. Their structures were elucidated through comprehensive 1D-/2D-NMR and HRESIMS spectroscopic data analysis. The cytotoxicity against MV4-11 human leukemia cell by the Cell Counting Kit-8 (CCK8) method was evaluated using isolated compounds with triptolide as positive control (IC50 1.1 ± 0.4 μM). Huoshanmycins A and B (1, 2) displayed moderate cytotoxicity with IC50 values of 32.9 ± 7.2 and 33.2 ± 6.1 μM, respectively.Hydroxymethylation is a simple chemical reaction, in which the introduction of the hydroxymethyl group can lead to physical-chemical property changes and offer several therapeutic advantages, contributing to the improved biological activity of drugs. There are many examples in the literature of the pharmaceutical, pharmacokinetic, and pharmacodynamic benefits, which the hydroxymethyl group can confer to drugs, prodrugs, drug metabolites, and other therapeutic compounds. It is worth noting that this group can enhance the drug’s interaction with the active site, and it can be employed as an intermediary in synthesizing other therapeutic agents. In addition, the hydroxymethyl derivative can result in more active compounds than the parent drug as well as increase the water solubility of poorly soluble drugs. Taking this into consideration, this review aims to discuss different applications of hydroxymethyl derived from biological agents and its influence on the pharmacological effects of drugs, prodrugs, active metabolites, and compounds of natural origin. Finally, we report a successful compound synthesized by our research group and used for the treatment of neglected diseases, which is created from the hydroxymethylation of its parent drug.Recently, the energy shortage has become increasingly prominent, and hydrogen (H2) energy has attracted extensive attention as a clean resource. Two-dimensional (2D) materials show excellent physical and chemical properties, which demonstrates considerable advantages in the application of photocatalysis compared with traditional materials. In this investigation, based on first-principles methods, 2D PtS2 and MoTe2 are selected to combine a heterostructure using van der Waals (vdW) forces, which suggests a type-II band structure to prevent the recombination of the photogenerated charges. Then, the calculated band edge positions reveal the decent ability to develop the redox reaction for water splitting at pH 0. Besides, the potential drop between the PtS2/MoTe2 vdW heterostructure interface also can separate the photogenerated electrons and holes induced by the charge density difference of the PtS2 and MoTe2 layers. Moreover, the fantastic optical performances of the PtS2/MoTe2 vdW heterostructure further explain the promising advanced usage for photocatalytic decomposition of water.Solar-driven vapor generation is emerging as an eco-friendly and cost-effective water treatment technology for harvesting solar energy. Aerogels are solid materials with desirable high-performance properties, including low density, low thermal conductivity, and high porosity with a large internal surface, which exhibit outstanding performance in the area of solar vapor generation. Using fibers as building blocks in aerogels could achieve unexpected performance in solar vapor generation due to their entangled fibrous network and high surface area. In this review, based on the fusion of the one-dimensional fibers and three-dimensional porous aerogels, we discuss recent development in fibrous aerogels for solar vapor generation based on building blocks synthesis, photothermal materials selection, pore structures construction and device design. Thermal management and water management of fibrous aerogels are also evaluated to improve evaporation performance. Focusing on materials science and engineering, we overview the key challenges and future research opportunities of fibrous aerogels in both fundamental research and practical application of solar vapor generation technology.
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