The epithelial–mesenchymal transition (EMT) program has emerged as a central driver of tumor malignancy. Moreover, the recently uncovered link between passage through an EMT and acquisition of ...stem-like properties indicates that activation of the EMT programs serves as a major mechanism for generating cancer stem cells (CSCs); that is, a subpopulation of cancer cells that are responsible for initiating and propagating the disease. In this review, we summarize the evidence supporting the widespread involvement of the EMT program in tumor pathogenesis and attempt to rationalize the connection between the EMT program and acquisition of stem cell traits. We propose that epithelial–mesenchymal plasticity is likely controlled by multiple varients of the core EMT program, and foresee the need to resolve the various programs and the molecular mechanisms that underlie them.
Significant effort has been made to develop novel material systems to improve the efficiency of near‐infrared organic light‐emitting diodes (NIR OLEDs). Of those, fluorescent chromophores are mostly ...studied because of their advantages in cost and tunability. However, it is still rare for fluorescent NIR emitters to present good color purities in the NIR range and to have high external quantum efficiency (EQE). Here, a wedge‐shaped D‐π‐A‐π‐D emitter APDC‐DTPA with thermally activated delayed fluorescence property and a small single‐triplet splitting (ΔEst) of 0.14 eV is presented. The non‐doped NIR device exhibits excellent performance with a maximum EQE of 2.19% and a peak wavelength of 777 nm. Remarkably, when 10 wt% of APDC‐DTPA is doped in 1,3,5‐tris(1‐phenyl‐1H‐benzimidazol‐2‐yl)benzene host, an extremely high EQE of 10.19% with an emission peak of 693 nm is achieved. All these values represent the best result for NIR OLEDs based on a pure organic fluorescent emitter with similar device structure and color gamut.
A near‐infrared (NIR) thermally activated delayed fluorescence material, APDC‐DTPA, containing acenaphtho1,2‐bpyrazine‐8,9‐dicarbonitrile unit as acceptor and diphenylamine as donor unit is developed. A non‐doped device based on APDC‐DTPA exhibits a maximum external quantum efficiency (EQE) of 2.19% with an emission peak at 777 nm. A maximum EQE of up to 10.19% is achieved in a doped NIR device (λEL = 693 nm).
Background:
Baduanjin exercise is a traditional Chinese Qigong exercise. This study aimed to investigate the effects of Baduanjin exercise on the quality of life and psychological status of ...postoperative patients with breast cancer.
Methods:
A systematic review and meta-analysis were conducted. Eight databases were searched from inception to December 15, 2021, restricting the language to English and Chinese. RevMan5.3 software was employed for data analysis. This study was registered in PROSPERO, number CRD 42020222132.
Results:
A total of 7 randomized controlled trials (RCTs) with 450 postoperative breast cancer patients with or without Baduanjin exercise were collected. Compared with the group without Baduanjin, those who practiced Baduanjin showed significant improvement in quality of life (WMD = 5.70, 95% CI 3.11-8.29, P < .0001). Subgroup analysis showed significant improvement in physical (WMD = 1.83, 95% CI 1.13-2.53, P < .00001) and functional well-being (WMD = 1.58, 95% CI 0.77-2.39, P = .0001), which were measured by the functional assessment of cancer therapy-breast (FACT-B). Subgroup analysis also showed that role-physical (WMD = 11.49, 95% CI 8.86-14.13, P < .00001) and vitality (WMD = 8.58, 95% CI 5.60-11.56, P < .00001) were significantly increased, as measured by a 36-item Short Form survey (SF-36). In terms of psychological health, Baduanjin exercise reduced patients’ anxiety (WMD = −8.02, 95% CI −9.27 to −6.78, P < .00001) and depression (WMD = −4.45, 95% CI −5.62 to −3.28, P < .00001).
Conclusions:
Baduanjin is an effective exercise, which can significantly improve the quality of life and psychological health of breast cancer patients after operation.
A stereoselective Koenigs–Knorr glycosylation reaction under the catalysis of urea is described. This method is characterized by urea‐mediated hydrogen‐bond activation and subsequent glycosylation ...with glycosyl chlorides or bromides. Excellent yields and high anomeric selectivity can be achieved in most cases. Moreover, the low α‐stereoselectivity of glycosylations observed when using perbenzylated glucosyl donors can be greatly improved by the addition of tri‐(2,4,6‐trimethoxyphenyl)phosphine (TTMPP).
Sugar, sugar: Stereoselective Koenigs–Knorr glycosylation under urea catalysis is described. This method is characterized by urea‐mediated hydrogen‐bond activation and subsequent glycosylation with glycosyl chlorides or bromides. Excellent yields and high anomeric selectivity can be achieved in most cases, and the α‐stereoselectivity when using perbenzylated glucosyl donors is greatly improved by the addition of TTMPP.
Glycans have been hot topics in recent years due to their exhibition of numerous biological activities. However, the heterogeneity of their natural source and the complexity of their chemical ...synthesis impede the progress in their biological research. Thus, the development of glycan assembly strategies to acquire plenty of structurally well‐defined glycans is an important issue in carbohydrate chemistry. In this review, the latest advances in glycan assembly strategies from concepts to their applications in carbohydrate synthesis, including chemical and enzymatic/chemo‐enzymatic approaches, as well as solution‐phase and solid‐phase/tag‐assisted synthesis, are summarized. Furthermore, the automated glycan assembly techniques are also outlined.
The latest advances in glycan assembly strategies from concepts to their applications in carbohydrate synthesis, including chemical and enzymatic/chemo‐enzymatic approaches, as well as solution‐phase and solid‐phase/tag‐assisted synthesis, are summarized. Furthermore, the automated glycan assembly techniques are also outlined.
The introduction of metasurfaces has renewed the Snell's law and opened up new degrees of freedom to tailor the optical wavefront at will. Here, we theoretically demonstrate that the generalized ...Snell's law can be achieved for reflected acoustic waves based on ultrathin planar acoustic metasurfaces. The metasurfaces are constructed with eight units of a solid structure to provide discrete phase shifts covering the full 2π span with steps of π/4 by coiling up the space. By careful selection of the phase profiles in the transverse direction of the metasurfaces, some fascinating wavefront engineering phenomena are demonstrated, such as anomalous reflections, conversion of propagating waves into surface waves, planar aberration-free lens and nondiffracting Bessel beam generated by planar acoustic axicon. Our results could open up a new avenue for acoustic wavefront engineering and manipulations.
Dendritic cell-associated C-type lectin-1 (Dectin-1) receptor has been reported to be involved in neuroinflammation in Alzheimer's disease and traumatic brain injury. The present study was designed ...to investigate the role of Dectin-1 and its downstream target spleen tyrosine kinase (Syk) in early brain injury after ischemic stroke using a focal cortex ischemic stroke model.
Adult male C57BL/6 J mice were subjected to a cerebral focal ischemia model of ischemic stroke. The neurological score, adhesive removal test, and foot-fault test were evaluated on days 1, 3, 5, and 7 after ischemic stroke. Dectin-1, Syk, phosphorylated (p)-Syk, tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS) expression was analyzed via western blotting in ischemic brain tissue after ischemic stroke and in BV2 microglial cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) injury in vitro. The brain infarct volume and Iba1-positive cells were evaluated using Nissl's and immunofluorescence staining, respectively. The Dectin-1 antagonist laminarin (LAM) and a selective inhibitor of Syk phosphorylation (piceatannol; PIC) were used for the intervention.
Dectin-1, Syk, and p-Syk expression was significantly enhanced on days 3, 5, and 7 and peaked on day 3 after ischemic stroke. The Dectin-1 antagonist LAM or Syk inhibitor PIC decreased the number of Iba1-positive cells and TNF-α and iNOS expression, decreased the brain infarct volume, and improved neurological functions on day 3 after ischemic stroke. In addition, the in vitro data revealed that Dectin-1, Syk, and p-Syk expression was increased following the 3-h OGD and 0, 3, and 6 h of reperfusion in BV2 microglial cells. LAM and PIC also decreased TNF-α and iNOS expression 3 h after OGD/R induction.
Dectin-1/Syk signaling plays a crucial role in inflammatory activation after ischemic stroke, and further investigation of Dectin-1/Syk signaling in stroke is warranted.
Photocatalytic CO2 reduction to CH4 requires photosensitizers and sacrificial agents to provide sufficient electrons and protons through metal‐based photocatalysts, and the separation of CH4 from ...by‐product O2 has poor applications. Herein, we successfully synthesize a metal‐free photocatalyst of a novel electron‐acceptor 4,5,9,10‐pyrenetetrone (PT), to our best knowledge, this is the first time that metal‐free catalyst achieves non‐sacrificial photocatalytic CO2 to CH4 and easily separable H2O2. This photocatalyst offers CH4 product of 10.6 μmol ⋅ g−1 ⋅ h−1 under non‐sacrificial ambient conditions (room temperature, and only water), which is two orders of magnitude higher than that of the reported metal‐free photocatalysts. Comprehensive in situ characterizations and calculations reveal a multi‐step reaction mechanism, in which the long‐lived oxygen‐centered radical in the excited PT provides as a site for CO2 activation, resulting in a stabilized cyclic carbonate intermediate with a lower formation energy. This key intermediate is thermodynamically crucial for the subsequent reduction to CH4 product with the electronic selectivity of up to 90 %. The work provides fresh insights on the economic viability of photocatalytic CO2 reduction to easily separable CH4 in non‐sacrificial and metal‐free conditions.
A metal‐free photocatalyst achieves high electronic selectivity for CH4 and facile separation of H2O2 in non‐sacrificial ambient conditions with only CO2 and H2O. This exceptional performance is attributed to a long‐lived oxygen‐centered radical in the excited electron acceptor, promoting the formation of a stabilized five‐member‐ring cyclic intermediate with lower energy, leading to an 90 % selectivity for the eight‐electron product CH4.
Conspectus Carbohydrates are called the third chain of life. Carbohydrates participate in many important biochemical functions in living species, and the biological information carried by them is ...several orders of magnitude larger than that of nucleic acids and proteins. However, due to the intrinsic complexity and heterogeneity of carbohydrate structures, furnishing pure and structurally well-defined glycans for functional studies is a formidable task, especially for homogeneous large-size glycans. To address this issue, we have developed a donor preactivation-based one-pot glycosylation strategy enabling multiple sequential glycosylations in a single reaction vessel. The donor preactivation-based one-pot glycosylation refers to the strategy in which the glycosyl donor is activated in the absence of a glycosyl acceptor to generate a reactive intermediate. Subsequently, the glycosyl acceptor with the same anomeric leaving group is added, leading to a glycosyl coupling reaction, which is then iterated to rapidly achieve the desired glycan in the same reactor. The advantages of this strategy include the following: (1) unique chemoselectivity is obtained after preactivation; (2) it is independent of the reactivity of glycosyl donors; (3) multiple-step glycosylations are enabled without the need for intermediate purification; (4) only stoichiometric building blocks are required without complex protecting group manipulations. Using this protocol, a range of glycans including tumor-associated carbohydrate antigens, various glycosaminoglycans, complex N-glycans, and diverse bacterial glycans have been synthesized manually. Gratifyingly, the synthesis of mycobacterial arabinogalactan containing 92 monosaccharide units has been achieved, which created a precedent in the field of polysaccharide synthesis. Recently, the synthesis of a highly branched arabinogalactan from traditional Chinese medicine featuring 140 monosaccharide units has been also accomplished to evaluate its anti-pancreatic-cancer activity. In the spirit of green and sustainable chemistry, this strategy can also be applied to light-driven glycosylation reactions, where either UV or visible light can be used for the activation of glycosyl donors. Automated synthesis is an advanced approach to the construction of complex glycans. Based on the two preactivation modes (general promoter activation mode and light-induced activation mode), a universal and highly efficient automated solution-phase synthesizer was further developed to drive glycan assembly from manual to automated synthesis. Using this synthesizer, a library of oligosaccharides covering various glycoforms and glycosidic linkages was assembled rapidly, either in a general promoter-activation mode or in a light-induced-activation mode. The automated synthesis of a fully protected fondaparinux pentasaccharide was realized on a gram scale. Furthermore, the automated synthesis of large-size polysaccharides was performed, allowing the assembly of arabinans up to an astonishing 1080-mer using the automated multiplicative synthesis strategy, taking glycan synthesis to a new height far beyond the synthesis of nucleic acids (up to 200-mer) and proteins (up to 472-mer).
Organic cocrystals possess valuable properties owing to the synergistic effect of the individual components. However, the growth of molecular cocrystals is still in its primary stage. Here we develop ...a microspacing in-air sublimation method to grow organic cocrystals, and furthermore to realize morphology control on them, which is essential for structure-property relations. A series of polycyclic aromatic hydrocarbon (PAH)‒1,2,4,5-tetracyanobenzene (TCNB) complexes cocrystals are grown directly on the substrate, with the morphology tunable from 1D needle-like to 2D plate-like on demand. Spatially resolved photoluminescence spectra analyses on different cocrystals display morphology dependent and anisotropic optical waveguiding properties. In situ observation and energy calculations of the crystallization processes reveal the formation mechanism being from a competition between growth kinetics-defined crystal habit and the thermodynamics driving force. This growth technique may serve the future demand for tunable morphology organic cocrystals in different functional applications.
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