The development of versatile nanotheranostic platforms that integrate both diagnostic and therapeutic functions have always been an intractable challenge in precise cancer treatment. Herein, an ...aptamer‐tethered deoxyribonucleic acids‐gold particle (Apt‐DNA‐Au) nanomachine has been developed for in situ imaging and targeted multimodal synergistic therapy of mammary carcinoma. Upon specifically internalized into MCF‐7 cells, the tumor‐related TK1 mRNA activates the Apt‐DNA‐Au nanomachine by DNA strand displacement cascades, resulting in the release of the fluorophore and antisense DNA as well as the aggregation of AuNPs for in situ imaging, suppression of survivin expression and photothermal therapy, respectively. Meanwhile, the controlled released drugs are used for chemotherapy, while under the laser irradiation the loaded photosensitizer produces reactive oxygen species (ROS) for photodynamic therapy. The results confirm that the proposed Apt‐DNA‐Au nanomachine provides a powerful nanotheranostic platform for in situ imaging‐guided combinatorial anticancer therapy.
A multifunctional DNA‐Au nanomachine which can be triggered by endogenous tumor growth‐related TK1 mRNA has been devised as the combinatorial theranostic agent for fluorescence imaging‐guided chemo, genic, photodynamic, and photothermal synergistic targeted therapy of breast cancer. This theranostic nanoplatform achieves the significant inhibition of tumor growth and improvement of therapeutic efficacy through in situ imaging.
Objectives To explore the prevalence and associated factors of burnout among five different medical professions in a regional teaching hospital. Design Cross-sectional study. Setting Hospital-based ...survey. Participants A total of 1329 medical professionals were recruited in a regional hospital with a response rate of 89%. These voluntary participants included 101 physicians, 68 physician assistants, 570 nurses, 216 medical technicians and 374 administrative staff. Primary and secondary outcome measures Demographic data included gender, age, level of education and marital status, and work situations, such as position, work hours and work shifts, were obtained from an electronic questionnaire. Job strain and burnout were measured by two validated questionnaires, the Chinese version of the Job Content Questionnaire and the Copenhagen Burnout Inventory. Results Among the five medical professions, the prevalence of high work-related burnout from highest to lowest was nurses (66%), physician assistants (61.8%), physicians (38.6%), administrative staff (36.1%) and medical technicians (31.9%), respectively. Hierarchical regression analysis indicated that job strain, overcommitment and low social support explained the most variance (32.6%) of burnout. Conclusions Physician assistant is an emerging high burnout group; its severity is similar to that of nurses and far more than that of physicians, administrative staff and medical technicians. These findings may contribute to the development of feasible strategies to reduce the stress which results in the burnout currently plaguing most hospitals in Taiwan.
Hetero-Diels-Alder (HDA) reaction is an important synthetic method for many natural products. An iron(III) catalyst was developed to catalyze the challenging HDA reaction of unactivated aldehydes and ...dienes with high selectivity. Here we report extensive density-functional theory (DFT) calculations and molecular dynamics simulations that show effects of iron (including its coordinate mode and/or spin state) on the dynamics of this reaction: considerably enhancing dynamically stepwise process, broadening entrance channel and narrowing exit channel from concerted asynchronous transition states. Also, our combined computational and experimental secondary KIE studies reveal unexpectedly large KIE values for the five-coordinate pathway even with considerable C-C bond forming, due to equilibrium isotope effect from the change in the metal coordination. Moreover, steric and electronic effects are computationally shown to dictate the C=O chemoselectivity for an α,β-unsaturated aldehyde, which is verified experimentally. Our mechanistic study may help design homogeneous, heterogeneous and biological catalysts for this challenging reaction.
Background:
Platelet-rich plasma (PRP) contains various cytokines and growth factors that may be beneficial to the healing process of injured muscle. Based on the authors’ previous study, PRP ...releasate can promote proliferation and migration of skeletal muscle cells in vitro, so animal studies are performed to support the use of PRP to treat muscle injury in vivo.
Purpose:
To investigate the effect of PRP releasate on regeneration of injured muscle, as well as its effect on inflammatory reaction and cell apoptosis, in the early stages of the muscle-healing process.
Study Design:
Controlled laboratory study.
Methods:
The gastrocnemius muscles of Sprague-Dawley rats were injured by partial transverse incision and then treated with PRP releasate. Hematoxylin and eosin stain was used to evaluate the healing process of injured muscle at 2, 5, and 10 days after injury. TUNEL assay was used to evaluate the cell apoptosis of injured muscle after PRP releasate treatment. Immunohistochemistry was used to stain the CD68-positive cells during the healing process. Muscle contractile properties, including fast-twitch and tetanic strength, were evaluated by electric stimulation.
Results:
The results revealed that PRP releasate treatment could enhance the muscle-healing process and decrease CD68-positive cells and apoptotic cells. Furthermore, the tetanic strength was significantly higher in injured muscle treated with PRP releasate.
Conclusion:
In conclusion, PRP releasate could enhance the healing process of injured muscle and decrease inflammatory cell infiltration as well as cell apoptosis.
Clinical Relevance:
PRP promotes skeletal muscle healing in association with decreasing inflammation and apoptosis of injured skeletal muscle. These findings provide in vivo evidence to support the use of PRP to treat muscle injury.
Secoisolariciresinol (SECO) is one of the major lignans occurring in various grains, seeds, fruits, and vegetables. The gut microbiota plays an important role in the biotransformation of dietary ...lignans into enterolignans, which might exhibit more potent bioactivities than the precursor lignans. This study aimed to identify, synthesize, and evaluate the microbial metabolites of SECO and to develop efficient lead compounds from the metabolites for the treatment of osteoporosis. SECO was fermented with human gut microbiota in anaerobic or micro-aerobic environments at different time points. Samples derived from microbial transformation were analyzed using an untargeted metabolomics approach for metabolite identification. Nine metabolites were identified and synthesized. Their effects on cell viability, osteoblastic differentiation, and gene expression were examined. The results showed that five of the microbial metabolites exerted potential osteogenic effects similar to those of SECO or better. The results suggested that the enterolignans might account for the osteoporotic effects of SECO in vivo. Thus, the presence of the gut microbiota could offer a good way to form diverse enterolignans with bone-protective effects. The current study improves our understanding of the microbial transformation products of SECO and provides new approaches for new candidate identification in the treatment of osteoporosis.
Monitoring and characterization methods that provide performance tracking of hydrogen evolution reaction (HER) at the single-nanoparticle level can greatly advance our understanding of catalysts’ ...structure and activity relationships. Electrochemiluminescence (ECL) microscopy is implemented for the first time to identify HER activities of single nanocatalysts and to provide a direction for further optimization. Here, we develop a novel ECL blinking technique at the single-nanoparticle level to directly monitor H2 nanobubbles generated from hollow carbon nitride nanospheres (HCNSs). The ECL ON and OFF mechanisms are identified being closely related to the generation, growth, and collapse of H2 nanobubbles. The power-law distributed durations of ON and OFF states demonstrate multiple catalytic sites with stochastic activities on a single HCNS. The power-law coefficients of ECL blinking increase with improved HER activities from modified HCNSs with other active HER catalysts. Besides, ECL blinking phenomenon provides an explanation for the low cathodic ECL efficiency of semiconductor nanomaterials.
In light of environmental concerns and energy demand, significant progress has been made toward CO2 reduction with high activity and selectivity. Particular interest has been focused on liquid ...products because of the easier separation process and higher value comparing to traditional gaseous products. Formic acid (or formate) can be one of the most economically viable reduction products. Nevertheless, few catalysts can meet the requirement for commercial-viable production, especially the current density. Herein, a hierarchical-Sn3O4 nanosheet (H–Sn3O4 NS) electrocatalyst is synthesized and applied into a three-compartment CO2 flow cell electrolyzer with ultra-high current density. The as-synthesized H–Sn3O4 NS electrocatalyst enables electrochemical CO2 reduction to formate with the selectivity of 91.1% at −1.02 V versus reversible hydrogen electrode (RHE) as well as a partial current density of 421 mA cm−2, whose performance is among the best that has been reported for CO2 electrocatalysts. The superior performance is due to the three-dimensional (3D) hierarchical structure, which supplies a large electrochemical surface area (ECSA) to facilitate mass and charge transfer. And the stability study with in-situ Raman spectroscopy and XRD characterization exhibited that the Sn3O4 materials could still maintain its original oxidation state under the maximum formate Faradaic efficiency of CO2 reduction reaction (CO2RR). The further theoretical calculation shows that the catalyst surface is beneficial for the formation of OCHO* (the intermediate of formate) than COOH* (the intermediate of CO) or H* (the intermediate of H2), which is in favor of the high activity and selectivity for formate in the experiments.
The synthesized 3D hierarchical-Sn3O4 nanosheet electrocatalyst enables electrochemical CO2 reduction to formate with the selectivity of 91.1% at −1.02 V (versus reversible hydrogen electrode) as well as a partial current density of 421 mA cm−2, whose performance is among the best that has been reported for CO2 electrocatalysts. Display omitted
•Hierarchical Sn3O4 NSs are synthesized as CO2RR electrocatalysts for the first time.•The as-prepared catalysts show remarkable performance due to its ingenious structure.•A ultra-high formate current density of 465.1 mA cm−2 was obtained at −1.02V vs RHE.•DFT calculations show that the catalyst surface is beneficial for the formation of OCHO*.
Muscle injuries are common among athletes and often treated with platelet‐rich plasma (PRP). However, whether the leukocyte concentration affects the efficacy of PRP in treating muscle injuries ...remains unclear. This study investigated the effects of leukocyte‐poor platelet‐rich plasma (LP‐PRP) and leukocyte‐rich platelet‐rich plasma (LR‐PRP) on myoblast proliferation and the molecular mechanisms underlying these effects. Myoblasts were treated with 0.5% LP‐PRP, 0.5% LR‐PRP, 1% LP‐PRP, or 1% LR‐PRP for 24 h. The gene expression of the LP‐PRP‐ and LR‐PRP–treated myoblasts was determined using RNA sequencing analysis. Cell proliferation was evaluated using an bromodeoxyuridine (BrdU) assay, and cell cycle progression was assessed through flow cytometry. The expression of cyclin A, cyclin‐dependent kinase 1 (cdk1), and cdk2 was examined using Western blotting. The expression of myoblast determination protein 1 (MyoD1) was examined through Western blotting and immunofluorescence staining. The LP‐PRP and LR‐PRP both promoted the proliferation of myoblasts and increased differential gene expression of myoblasts. Moreover, the LP‐PRP and LR‐PRP substantially upregulated the expression of cyclin A, cdk1, and cdk2. MyoD1 expression was induced in the LP‐PRP and LR‐PRP–treated myoblasts. Our results corroborate the finding that LP‐PRP and LR‐PRP have similar positive effects on myoblast proliferation and MyoD1 expression.
Nitrocellulose (NC) is widely used in both military and civilian fields. Because of its high chemical sensitivity and low decomposition temperature, NC is prone to spontaneous combustion. Due to the ...dangerous properties of NC, it is often dissolved in other organic solvents, then stored and transported in the form of a solution. Therefore, this paper took NC solutions (NC-S) with different concentrations as research objects. Under different atmospheric conditions, a series of thermal analysis experiments and different reaction kinetic methods investigated the influence of solution concentration and oxygen concentration on NC-S's thermal stability. The variation rules of NC-S's thermodynamic parameters with solution and oxygen concentrations were explored. On this basis, the spontaneous combustion characteristics of NC-S under actual industrial conditions were summarized to put forward the theoretical guidance for the spontaneous combustion treatment together with the safety in production, transportation, and storage.
In recent years, the prosperous electric vehicle industry has contributed to the rapid development of lithium-ion batteries. However, the increase in the energy density of lithium-ion batteries has ...also created more pressing safety concerns. The emergence of a new flame-retardant material with the additive ethoxy (pentafluoro) cyclotriphosphazene can ameliorate the performance of lithium-ion batteries while ensuring their safety. The present study proposes a new polymer composite flame-retardant electrolyte and adopts differential scanning calorimetry (DSC) and accelerating rate calorimetry to investigate its thermal effect. The study found that the heating rate is positively correlated with the onset temperature, peak temperature, and endset temperature of the endothermic peak. The flame-retardant modified polymer electrolyte for new lithium-ion batteries has better thermal stability than traditional lithium-ion battery electrolytes. Three non-isothermal methods (Kissinger; Kissinger–Akahira–Sunose; and Flynn–Wall–Ozawa) were also used to calculate the kinetic parameters based on the DSC experimental data. The apparent activation energy results of the three non-isothermal methods were averaged as 54.16 kJ/mol. The research results can provide valuable references for the selection and preparation of flame-retardant additives in lithium-ion batteries.
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