In recent years, emulsions stabilized by micro‐ or nanoparticles (known as Pickering emulsions) have attracted much attention. Micro‐ or nanoparticles, as the main components of the emulsion, play a ...key role in the preparation and application of Pickering emulsions. The existence of particles at the interface between the oil and aqueous phases affects not only the preparation, but also the properties of Pickering emulsions, affording superior stability, low toxicity, and stimuli‐responsiveness compared to classical emulsions stabilized by surfactants. These advantages of Pickering emulsions make them attractive, especially in biomedicine. In this review, the effects of the characteristics of micro‐ and nanoparticles on the preparation and properties of Pickering emulsions are introduced. In particular, the preparation methods of Pickering emulsions, especially uniform‐sized emulsions, are listed. Uniform Pickering emulsions are convenient for both mechanistic research and applications. Furthermore, some biomedical applications of Pickering emulsions are discussed and the problems hindering their clinical application are identified.
Pickering emulsions, stabilized by particles, have attracted much attention in recent years. Due to the introduction of particles at the interface between oil and aqueous phases, Pickering emulsions possess many distinctive properties such as high stability and low toxicity, when compared with classical emulsions stabilized by surfactants. These properties also affect their applications, especially in biomedical fields, such as oral or topical delivery systems.
Postoperative cognitive dysfunction (POCD) is a very common complication that might increase the morbidity and mortality of elderly patients after surgery. However, the mechanism of POCD remains ...largely unknown. The NAD-dependent deacetylase protein Sirtuin 3 (SIRT3) is located in the mitochondria and regulates mitochondrial function. SIRT3 is the only sirtuin that specifically plays a role in extending lifespan in humans and is associated with neurodegenerative diseases. Therefore, the aim of this study was to evaluate the effect of SIRT3 on anesthesia/surgery-induced cognitive impairment in aged mice.
SIRT3 expression levels were decreased after surgery. For the interventional study, an adeno-associated virus (AAV)-SIRT3 vector or an empty vector was microinjected into hippocampal CA1 region before anesthesia/surgery. Western blotting, immunofluorescence staining, and enzyme-linked immune-sorbent assay (ELISA) were used to measure the oxidative stress response and downstream microglial activation and proinflammatory cytokines, and Golgi staining and long-term potentiation (LTP) recording were applied to evaluate synaptic plasticity.
Overexpression of SIRT3 in the CA1 region attenuated anesthesia/surgery-induced learning and memory dysfunction as well as synaptic plasticity dysfunction and the oxidative stress response (superoxide dismutase SOD and malondialdehyde MDA) in aged mice with POCD. In addition, microglia activation (ionized calcium binding adapter molecule 1 Iba1) and neuroinflammatory cytokine levels (tumor necrosis factor-alpha TNF-α, interleukin IL-1β and IL-6) were regulated after anesthesia/surgery in a SIRT3-dependent manner.
The results of the current study demonstrate that SIRT3 has a critical effect in the mechanism of POCD in aged mice by suppressing hippocampal neuroinflammation and reveal that SIRT3 may be a promising therapeutic and diagnostic target for POCD.
Breast cancer has grown to be the second leading cause of cancer-related deaths in women. Only a few treatment options are available for breast cancer due to the widespread occurrence of ...chemoresistance, which emphasizes the need to discover and develop new methods to treat this disease. Signal transducer and activator of transcription 3 (STAT3) is an early tumor diagnostic marker and is known to promote breast cancer malignancy. Recent clinical and preclinical data indicate the involvement of overexpressed and constitutively activated STAT3 in the progression, proliferation, metastasis and chemoresistance of breast cancer. Moreover, new pathways comprised of upstream regulators and downstream targets of STAT3 have been discovered. In addition, small molecule inhibitors targeting STAT3 activation have been found to be efficient for therapeutic treatment of breast cancer. This systematic review discusses the advances in the discovery of the STAT3 pathways and drugs targeting STAT3 in breast cancer. Video abstract.
For seeking high enantiopurity, the previously reported thermal asymmetric catalysis is usually carried out at low temperature sometimes with limited yield, that is, the high enantiomeric excess (ee) ...usually at the cost of high yield. Thus, the achieving both high stereoselectivity and yield is an enormous challenge. We report herein two metal nanoparticle (M NP)-loaded and porphyrin-containing homochiral covalent organic framework (CCOF)-based composite catalysts, and their application in the thermally-driven asymmetric one-pot Henry and A
-coupling reactions. All the reactions are conducted at elevated temperatures with both excellent stereoselectivity and yield which resulted from the synergy of CCOF confinement effect and M NP catalytic activation. Notably, the needed thermal energy for the asymmetric reactions herein is derived from the photothermal conversion via porphyrin-based CCOF upon irradiation with visible light. Remarkably, the CCOF confinement effect can be effectively maintained up to 100 °C for the asymmetric one-pot Henry and A
-coupling reactions herein.
•The interaction between the channel structure and logistics mode is studied.•The conditions for both firms to agree on adding the marketplace channel are obtained.•The logistics service affects ...consumer purchase behavior more than price.•The supplier is always willing to add the channel and undertake logistics.•The platform and the supplier can realize a win–win situation in some case.
In online retailing, in addition to the reseller channel, the marketplace channel has been favored by many e-commerce platforms and suppliers. Different from the reseller channel, the novel channel enables suppliers to obtain the pricing power of products and to have direct contact with consumers. However, due to the operation inefficiency of suppliers and the competition caused by adding a new channel, for suppliers and platforms, decisions on the establishment of the marketplace channel are more complex. In addition, logistics service, which affects the purchase behavior of online consumers and is considered the key to the success of online retailing, can be undertaken by both suppliers and platforms. Based on these considerations, this paper explores whether the supplier and the platform can come to an agreement on introducing the marketplace channel by incorporating the logistics service strategy. We find that compared with the product sales price, the level of logistics service has a stronger impact on the consumers’ channel choice. A scenario we term RE-MS (the marketplace channel is established, and the platform and the supplier serve as the logistics providers in the reseller and the marketplace channels, respectively) produces the highest level of logistics service in the reseller channel, and a scenario termed RS-MS (the marketplace channel is established, and the supplier serves as the logistics provider in both channels) generates the highest level of logistics service in the marketplace channel. The supplier is always willing to add the marketplace channel and undertake logistics business in the marketplace channel. However, for the platform, adding the marketplace channel is advantageous only when the logistics service effectiveness or the commission rate is high. Additionally, when the supplier and the platform reach a consensus on the establishment of the marketplace channel, the RE-MS strategy can realize a win–win situation.
In this paper, we present an update to the models used to calculate the remaining life of transformer paper insulation. A drawback to the current IEEE method is that it does not take into account the ...availability of water and oxygen on the life expectancy of Kraft paper insulation. We therefore set out to test an algorithm which does take these into account. For our investigation, we loaded three test transformers and ran them to near their end of life. Kinetic equations were applied to model the fall in the degree of polymerization of paper. Our model showed better agreement with the test results than that given from using the IEEE standard. The IEEE standard gives life expectancy for Kraft paper being aged in minimal oxygen under dry conditions, which is not necessarily representative of an old transformer. Wet paper and using high levels of oxygen can age nearly 40 times faster. The IEEE method needs to take the synergistic effect of water and oxygen on increasing the rate of paper aging into account.
It is well‐known that tissue engineering scaffolds that feature highly interconnected and size‐adjustable micropores are oftentimes desired to promote cellular viability, motility, and functions. ...Unfortunately, the ability of precise control over the microporous structures within bioinks in a cytocompatible manner for applications in 3D bioprinting is generally lacking, until a method of micropore‐forming bioink based on gelatin methacryloyl (GelMA) was reported recently. This bioink took advantage of the unique aqueous two‐phase emulsion (ATPE) system, where poly(ethylene oxide) (PEO) droplets are utilized as the porogen. Considering the limitations associated with this very initial demonstration, this article has furthered the understanding of the micropore‐forming GelMA bioinks by conducting a systematic investigation into the additional GelMA types (porcine and fish, different methacryloyl‐modification degrees) and porogen types (PEO, poly(vinyl alcohol), and dextran), as well as the effects of the porogen concentrations and molecular weights on the properties of the GelMA‐based ATPE bioink system. This article exemplifies not only the significantly wider range of micropore sizes achievable and better emulsion stability, but also the improved suitability for both extrusion and digital light processing bioprinting with favorable cellular responses.
A micropore‐forming gelatin methacryloyl (GelMA) aqueous two‐phase bioink toolbox 2.0 is reported with a systematic investigation into a variety of GelMA types and porogen types. This article exemplifies not only the significantly wider range of micropore sizes achievable and better emulsion stability than the initial version, but also the improved suitability for various bioprinting modalities featuring favorable cellular responses.
Owing to their permanent porosity, highly ordered and extended structure, good chemical stability, and tunability, covalent organic frameworks (COFs) have emerged as a new type of organic materials ...that can offer various applications in different fields. Benefiting from the huge database of organic reactions, the required functionality of COFs can be readily achieved by modification of the corresponding organic functional groups on either polymerizable monomers or established COF frameworks. This striking feature allows homochiral covalent organic frameworks (HCCOFs) to be reasonably designed and synthesized, as well as their use as a unique platform to fabricate asymmetric catalysts. This contribution provides an overview of new progress in HCCOF‐based asymmetric catalysis, including design, synthesis, and their application in asymmetric organic synthesis. Moreover, major challenges and developing trends in this field are also discussed. It is anticipated that this review article will provide some new insights into HCCOFs for heterogeneous asymmetric catalysis and help to encourage further contributions in this young but promising field.
Chirality from COFs: Owing to their permanent porosity, highly ordered and extended structure, good chemical stability, and tunability, covalent organic frameworks have emerged as a new type of organic materials that can offer various applications in different fields. Herein, the design and synthesis of chiral covalent organic frameworks and their applications in asymmetric catalysis are highlighted.
Aim
Endometriosis is a common gynecological disorder characterized by chronic pelvic pain and infertility, which negatively affects women's health worldwide. AFAP1‐AS1 has been implicated in ...endometriosis lesions recently, but its mechanism of endometriosis progression remains unclear.
Methods
Endometrial stromal cells (ESCs) were used to identify the role of AFAP1‐AS1 in endometriosis. The migratory capability was determined by transwell. Gene and protein expressions were identified by quantitative real‐time polymerase chain reaction (qRT‐PCR) and Western blotting. Cell viability and apoptosis were detected by MTT assays and flow cytometry, respectively. Luciferase report assays were used to identify the interaction of AFAP1‐AS1, miR‐424‐5p and signal transducer and activator of transcription 3 (STAT3).
Results
AFAP1‐AS1 knockdown or miR‐424‐5p overexpression inhibited proliferation and migration, and promoted apoptosis in ESCs. In addition, knockdown of AFAP1‐AS1 repressed the expression of ki‐67 and Bcl‐2, and promoted the levels of cleaved caspase‐3 and Bax. Furthermore, knockdown of AFAP1‐AS1 inhibited the conversion of E‐cadherin to N‐cadherin and the expression of Snail. Moreover, AFAP1‐AS1 activated the STAT3/transforming growth factor‐β1 (TGF‐β1)/Smad2 axis via directly targeting miR‐424‐5p. The regulatory effect of AFAP1‐AS1 silencing in ESC migration, proliferation, and apoptosis was reversed by miR‐424‐5p inhibition or STAT3 overexpression.
Conclusions
AFAP1‐AS1 silencing could inhibit cell proliferation and promote apoptosis by regulating STAT3/TGF‐β/Smad signaling pathway via targeting miR‐424‐5p in ESCs. AFAP1‐AS1 may be a potential therapeutic target of controlling the progression of endometriosis.
Accurate and rapid diagnosis of COVID-19 suspected cases plays a crucial role in timely quarantine and medical treatment. Developing a deep learning-based model for automatic COVID-19 diagnosis on ...chest CT is helpful to counter the outbreak of SARS-CoV-2. A weakly-supervised deep learning framework was developed using 3D CT volumes for COVID-19 classification and lesion localization. For each patient, the lung region was segmented using a pre-trained UNet; then the segmented 3D lung region was fed into a 3D deep neural network to predict the probability of COVID-19 infectious; the COVID-19 lesions are localized by combining the activation regions in the classification network and the unsupervised connected components. 499 CT volumes were used for training and 131 CT volumes were used for testing. Our algorithm obtained 0.959 ROC AUC and 0.976 PR AUC. When using a probability threshold of 0.5 to classify COVID-positive and COVID-negative, the algorithm obtained an accuracy of 0.901, a positive predictive value of 0.840 and a very high negative predictive value of 0.982. The algorithm took only 1.93 seconds to process a single patient's CT volume using a dedicated GPU. Our weakly-supervised deep learning model can accurately predict the COVID-19 infectious probability and discover lesion regions in chest CT without the need for annotating the lesions for training. The easily-trained and high-performance deep learning algorithm provides a fast way to identify COVID-19 patients, which is beneficial to control the outbreak of SARS-CoV-2. The developed deep learning software is available at https://github.com/sydney0zq/covid-19-detection .
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