Black phosphorus (BP) has increasingly attracted scientific attention since its first applications in biomedicine due to its unique properties and excellent biocompatibility. In particular, its ...layer‐dependent bandgap, moderate carrier mobility, large surface‐area‐to‐volume ratio, biodegradability, intrinsic photoacoustic properties, and biocompatibility make it an ideal candidate for use in photothermal therapy, photodynamic therapy, drug delivery, 3D printing, bioimaging, biosensing, and theranostics, which are reviewed here. In addition, the article discusses strategies to overcome challenges related to surface instability due to chemical degradation, a major obstacle for its application. This review not only provides a comprehensive summary on BP preparation and biomedical applications but also summarizes recent research and future possibilities.
2D black phosphorus is extensively used in biomedicine due to its excellent physical and chemical properties. This review focuses on the current progress and future perspectives of 2D black phosphorus–based biomedical applications, including cancer therapy, diagnosis, and theranostics. In addition, the article discusses strategies to overcome challenges related to surface instability, a major obstacle for its application.
K-12 teaching is a profession characterized by high levels of burnout and emotional exhaustion. Teacher burnout has been widely reviewed and studied; however, only limited literature examines the ...emotional aspects of teachers' lives and its connection with teacher burnout. The purpose of this article is to review the literature on teacher burnout and teachers' emotions and to examine the role of teachers' appraisal of their emotional exhaustion. Through reviewing the literature on teacher burnout and emotions, I argue that the habitual patterns in teachers' judgments about student behavior and other teaching tasks may contribute significantly to teachers' repeated experience of unpleasant emotions and those emotions may eventually lead to burnout. In order to ease teacher burnout, I argue that more studies on the antecedent appraisals that teachers make are necessary to help teachers better understand how their emotions were triggered and then learn how to regulate those emotions.
Lung cancer is the most commonly diagnosed cancer worldwide, and metastasis in lung cancer is the leading cause of cancer‐related deaths. Thus, understanding the mechanism of lung cancer metastasis ...will improve the diagnosis and treatment of lung cancer patients. Herein, we found that expression of cluster of differentiation 109 (CD109) was correlated with the invasive and metastatic capacities of lung adenocarcinoma cells. CD109 is upregulated in tumorous tissues, and CD109 overexpression was associated with tumor progression, distant metastasis, and a poor prognosis in patient with lung adenocarcinoma. Mechanistically, expression of CD109 regulates protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling via its association with the epidermal growth factor receptor (EGFR). Inhibition of CD109 decreases EGFR phosphorylation, diminishes EGF‐elicited activation of AKT/mTOR, and sensitizes tumor cells to an EGFR inhibitor. Taken together, our results show that CD109 is a potential diagnostic and therapeutic target in lung cancer patients.
CD109 promotes lung cancer metastasis through promoting EGFR‐AKT‐mTOR signaling and CD109 is an independent prognostic marker for lung adenocarcinoma.
Lysophosphatidylcholine (LPC) is increasingly recognized as a key marker/factor positively associated with cardiovascular and neurodegenerative diseases. However, findings from recent clinical ...lipidomic studies of LPC have been controversial. A key issue is the complexity of the enzymatic cascade involved in LPC metabolism. Here, we address the coordination of these enzymes and the derangement that may disrupt LPC homeostasis, leading to metabolic disorders. LPC is mainly derived from the turnover of phosphatidylcholine (PC) in the circulation by phospholipase A₂ (PLA₂). In the presence of Acyl-CoA, lysophosphatidylcholine acyltransferase (LPCAT) converts LPC to PC, which rapidly gets recycled by the Lands cycle. However, overexpression or enhanced activity of PLA₂ increases the LPC content in modified low-density lipoprotein (LDL) and oxidized LDL, which play significant roles in the development of atherosclerotic plaques and endothelial dysfunction. The intracellular enzyme LPCAT cannot directly remove LPC from circulation. Hydrolysis of LPC by autotaxin, an enzyme with lysophospholipase D activity, generates lysophosphatidic acid, which is highly associated with cancers. Although enzymes with lysophospholipase A₁ activity could theoretically degrade LPC into harmless metabolites, they have not been found in the circulation. In conclusion, understanding enzyme kinetics and LPC metabolism may help identify novel therapeutic targets in LPC-associated diseases.
Compared with other professions, teachers in P-12 schools appear to experience a higher level of emotional exhaustion (see review in Maslach et al. in Ann Rev Psychol 52(1):397,
2001
; Schaufeli and ...Enzmann in The burnout companion to study and practice: a critical analysis, Taylor & Francis, Philadelphia,
1998
). The purpose of this study is to examine teacher emotions within the context of teachers’ appraisals and the ways they regulate and cope with their emotions. The study explores teachers’ appraisals of disruptive classroom behavior situations and investigates the adaptive coping and emotion regulation strategies that ease teacher burnout. Data were collected from 492 teachers in the US Midwest and subjected to hypothesis testing using structural equation modeling. The model provides evidence supporting a pathway between teachers’ antecedent judgments and their experience of emotion, as well as providing evidence for how the consequent emotions contribute to teachers’ feelings of burnout. This study further validates the relationships between the appraisals teachers make about an incident and the correlative intensity of emotions. Several hypotheses are either supported or partially supported after testing alternate models. Discussion and implications regarding teacher emotion regulation and coping are provided.
Catalytic C(sp3)−H functionalization can convert abundant feedstock hydrocarbons into value‐added products in an atom‐ and step‐economic manner and is a powerful tool in organic synthesis. However, ...the intrinsic chemical inertness of ubiquitous aliphatic C−H bonds of alkanes and cycloalkanes makes their direct and selective functionalization extremely challenging. Recently, some elegant strategies have been developed to solve the problems based on the merger of photocatalyzed hydrogen atom transfer (HAT) with transition metal catalysis. Light‐induced HAT processes are employed to initiate the alkyl radical generation, which is synergistic with metal catalysis involving for example nickel, copper, cobalt, cerium, chromium, or manganese. The different metal catalysts provide redox adjustment, Lewis acid activation or other functionalities and tune the reactivity and selectivity of the radical‐mediated sequences, allowing the development of diverse chemo‐, site‐, and/or stereoselective synthetic reactions. In this minireview, we offer a brief summary of the recent advances in dual photo‐induced HAT and transition metal catalysis for C−H functionalization of alkanes and cycloalkanes. We expect that these methodologies will stimulate the applications in catalysis, pharmaceuticals, and other related fields.
Catalytic C(sp3)−H functionalization of alkanes and cycloalkanes is a useful tool to convert abundant chemical feedstocks into value‐added products but remains a challenging task. In this review, recent advances relying on dual photo‐induced hydrogen atom transfer and transition metal catalysis are summarized.
Evidence suggests that fasting exerts extensive antitumor effects in various cancers, including colorectal cancer (CRC). However, the mechanism behind this response is unclear. We investigate the ...effect of fasting on glucose metabolism and malignancy in CRC. We find that fasting upregulates the expression of a cholesterogenic gene, Farnesyl-Diphosphate Farnesyltransferase 1 (FDFT1), during the inhibition of CRC cell aerobic glycolysis and proliferation. In addition, the downregulation of FDFT1 is correlated with malignant progression and poor prognosis in CRC. Moreover, FDFT1 acts as a critical tumor suppressor in CRC. Mechanistically, FDFT1 performs its tumor-inhibitory function by negatively regulating AKT/mTOR/HIF1α signaling. Furthermore, mTOR inhibitor can synergize with fasting in inhibiting the proliferation of CRC. These results indicate that FDFT1 is a key downstream target of the fasting response and may be involved in CRC cell glucose metabolism. Our results suggest therapeutic implications in CRC and potential crosstalk between a cholesterogenic gene and glycolysis.
Multichromophoric macrocycles and cyclophanes are important supramolecular architectures for the elucidation of interchromophoric interactions originating from precise spatial organization. Herein, ...by combining an axially chiral binaphthol bisimide (BBI) and a bay‐substituted conformationally labile twisted perylene bisimide (PBI) within a cyclophane of well‐defined geometry, we report a chiral PBI hetero‐cyclophane (BBI‐PBI) that shows intramolecular energy and solvent‐regulated chirality transfer from the BBI to the PBI subunit. Excellent spectral overlap and spatial arrangement of BBI and PBI lead to efficient excitation energy transfer and subsequent PBI emission with high quantum yield (80–98 %) in various solvents. In contrast, chirality transfer is strongly dependent on the respective solvent as revealed by circular dichroism (CD) spectroscopy. The combination of energy and chirality transfer affords a bright red circularly polarized luminescence (CPL) from the PBI chromophore by excitation of BBI.
A chiral perylene bisimide (PBI) hetero‐cyclophane comprising a chiral binaphthol bisimide (BBI) dye and a dynamically racemic PBI dye shows quantitative energy and solvent‐dependent chirality transfer among its components, thereby leading to an amplified bright red circularly polarized luminescence from PBI.
Chronic mitochondrial stress associates with major neurodegenerative diseases. Recovering stressed mitochondria constitutes a critical step of mitochondrial quality control and thus energy ...maintenance in early stages of neurodegeneration. Here, we reveal Mul1-Mfn2 pathway that maintains neuronal mitochondrial integrity under stress conditions. Mul1 deficiency increases Mfn2 activity that triggers the first phasic mitochondrial hyperfusion and also acts as an ER-Mito tethering antagonist. Reduced ER-Mito coupling leads to increased cytoplasmic Ca
load that activates calcineurin and induces the second phasic Drp1-dependent mitochondrial fragmentation and mitophagy. Overexpressing Mfn2, but not Mfn1, mimics Mul1-deficient phenotypes, while expressing PTPIP51, an ER-Mito anchoring protein, suppresses Parkin-mediated mitophagy. Thus, by regulating mitochondrial morphology and ER-Mito contacts, Mul1-Mfn2 pathway plays an early checkpoint role in maintaining mitochondrial integrity. Our study provides new mechanistic insights into neuronal mitochondrial maintenance under stress conditions, which is relevant to several major neurodegenerative diseases associated with mitochondrial dysfunction and altered ER-Mito interplay.
Development of practical deuteration reactions is highly valuable for organic synthesis, analytic chemistry and pharmaceutic chemistry. Deuterodehalogenation of organic chlorides tends to be an ...attractive strategy but remains a challenging task. We here develop a photocatalytic system consisting of an aryl-amine photocatalyst and a disulfide co-catalyst in the presence of sodium formate as an electron and hydrogen donor. Accordingly, many aryl chlorides, alkyl chlorides, and other halides are converted to deuterated products at room temperature in air (>90 examples, up to 99% D-incorporation). The mechanistic studies reveal that the aryl amine serves as reducing photoredox catalyst to initiate cleavage of the C-Cl bond, at the same time as energy transfer catalyst to induce homolysis of the disulfide for consequent deuterium transfer process. This economic and environmentally-friendly method can be used for site-selective D-labeling of a number of bioactive molecules and direct H/D exchange of some drug molecules.
PDF
