Summary
Melanoma is the deadliest form of skin cancer and its incidence is rising, creating a costly and significant clinical problem. Exposure to ultraviolet (UV) radiation, namely UVA (315‐400 nm) ...and UVB (280‐315 nm), is a major risk factor for melanoma development. Cumulative UV radiation exposure from sunlight or tanning beds contributes to UV‐induced DNA damage, oxidative stress, and inflammation in the skin. A number of factors, including hair color, skin type, genetic background, location, and history of tanning, determine the skin's response to UV radiation. In melanocytes, dysregulation of this UV radiation response can lead to melanoma. Given the complex origins of melanoma, it is difficult to develop curative therapies and universally effective preventative strategies. Here, we describe and discuss the mechanisms of UV‐induced skin damage responsible for inducing melanomagenesis, and explore options for therapeutic and preventative interventions.
Reactome is a manually curated pathway annotation database for unveiling high-order biological pathways from high-throughput data.
ReactomePA
is an R/Bioconductor package providing enrichment ...analyses, including hypergeometric test and gene set enrichment analyses. A functional analysis can be applied to the genomic coordination obtained from a sequencing experiment to analyze the functional significance of genomic loci including
cis
-regulatory elements and non-coding regions. Comparison among different experiments is also supported. Moreover,
ReactomePA
provides several visualization functions to produce highly customizable, publication-quality figures. The source code and documents of
ReactomePA
are freely available through Bioconductor (
http://www.bioconductor.org/packages/ReactomePA
).
ReactomePA
is an R package providing functional analyses at the gene and sequence levels, with several visualization functions provided.
There is currently an urgent demand for highly efficient energy storage and conversion systems. Due to its high theoretical energy density, low cost, and environmental compatibility, the lithium ...sulfur (Li–S) battery has become a typical representative of the next generation of electrochemical power sources. Various approaches have been explored to design and prepare sulfur cathode materials to enhance their electrochemical performance. This Research News article summarizes and compares different sulfur materials for Li–S batteries and particularly focuses on the fine structures, electrochemical performance, and electrode reaction mechanisms of pyrolyzed polyacrylonitrile sulfur (pPAN@S) and microporous‐carbon/small‐sulfur composite materials.
pPAN@S and microporous‐carbon/small‐sulfur, in which sulfur molecules are homogeneously incorporated into conductive matrices, demonstrate high active sulfur utilization, nearly 100% Coulombic efficiency except for the first cycle, good capacity retention, and extremely low self‐discharge rates. This Research News article summarizes the recent advances in these two types of sulfur‐based composite cathode materials for rechargeable lithium batteries.
We report an experiment to test quantum interference, entanglement, and nonlocality using two dissimilar photon sources, the Sun and a semiconductor quantum dot on the Earth, which are separated by ...∼150 million kilometers. By making the otherwise vastly distinct photons indistinguishable in all degrees of freedom, we observe time-resolved two-photon quantum interference with a raw visibility of 0.796(17), well above the 0.5 classical limit, providing unambiguous evidence of the quantum nature of thermal light. Further, using the photons with no common history, we demonstrate postselected two-photon entanglement with a state fidelity of 0.826(24) and a violation of Bell inequality by 2.20(6). The experiment can be further extended to a larger scale using photons from distant stars and open a new route to quantum optics experiments at an astronomical scale.
Multidrug resistance (MDR) occurs frequently after long-term chemotherapy, resulting in refractory cancer and tumor recurrence. Therefore, combatting MDR is an important issue. Autophagy, a ...self-degradative system, universally arises during the treatment of sensitive and MDR cancer. Autophagy can be a double-edged sword for MDR tumors: it participates in the development of MDR and protects cancer cells from chemotherapeutics but can also kill MDR cancer cells in which apoptosis pathways are inactive. Autophagy induced by anticancer drugs could also activate apoptosis signaling pathways in MDR cells, facilitating MDR reversal. Therefore, research on the regulation of autophagy to combat MDR is expanding and is becoming increasingly important. We summarize advanced studies of autophagy in MDR tumors, including the variable role of autophagy in MDR cancer cells.
We report herein the first examples of a palladium‐catalyzed enantioselective Cacchi reaction for the synthesis of indoles bearing a chiral C2‐aryl axis. In the presence of a catalytic amount of ...Pd(OAc)2 and (R,R)‐QuinoxP* ligand, reaction of N‐aryl(alkyl)sulfonyl‐2‐alkynylanilides with arylboronic acids under oxygen atmosphere afforded enantioenriched 2,3‐disubstituted indoles in high yields and enantioselectivity. The indole ring is constructed de novo in this process and a complexation‐induced chirality transfer is proposed to account for the observed enantioselectivity.
Axially chiral indoles: In the presence of a chiral QuinoxP*PdII complex, two simple achiral building blocks undergo cyclizative cross‐coupling to afford 2,3‐disubstituted indoles bearing a C2‐aryl chiral axis in high yields and enantioselectivity. The indole ring is constructed de novo in this process and a complexation‐induced chirality transfer is proposed to account for the observed enantioselectivity.
Despite clinical applications of the first‐generation tissue adhesives and hemostats, the correlation among microstructure and hemostasis of hydrogels with wound healing is less understood and it is ...elusive to design high‐performance hydrogels to meet worldwide growing demands in wound closure, hemostasis, and healing. Inspired by the microstructure of extracellular matrix and mussel‐mimetic chemistry, two kinds of coordinated and covalent glycopolypeptide hydrogels are fabricated, which present tunable tissue adhesion strength (14.6–83.9 kPa) and microporous structure (8–18 µm), and lower hemolysis <1.5%. Remarkably, the microporous size mainly controls the hemostasis, and those hydrogels with larger pores of 16–18 µm achieve the fastest hemostasis of ≈14 s and the lowest blood loss of ≈6% than fibrin glue and others. Moreover, both biocompatibility and hemostasis affect wound healing performance, as assessed by hemolysis, cytotoxicity, subcutaneous implantation, and hemostasis and healing assays. Importantly, the glycopolypeptide hydrogel‐treated rat‐skin defect model achieves full wound closure and regenerates thick dermis and epidermis with some hair follicles on day 14. Consequently, this work not only establishes a versatile method for constructing glycopolypeptide hydrogels with tunable adhesion and microporous structure, fast hemostasis, and superior healing functions, but also discloses a useful rationale for designing high‐performance hemostatic and healing hydrogels.
Two kinds of coordinated and covalent glycopolypeptide hydrogels are fabricated, which present tunable tissue adhesion strength, microporous structure, and lower hemolysis. The large microporous hydrogels achieve superior hemostasis and regenerate thick dermis/epidermis with some hair follicles during wound healing. Significantly, this work discloses the correlation of microstructure‐hemostasis‐wound healing, guiding the design of high‐performance hydrogels‐based hemostatic and healing adhesives and dressings.
The photocatalyzed ortho‐selective migration on a pyridyl ring has been achieved for the site‐selective trifluoromethylative pyridylation of unactivated alkenes. The overall process is initiated by ...the selective addition of a CF3 radical to the alkene to provide a nucleophilic alkyl radical intermediate, which enables an intramolecular endo addition exclusively to the ortho‐position of the pyridinium salt. Both secondary and tertiary alkyl radicals are well‐suited for addition to the C2‐position of pyridinium salts to ultimately provide synthetically valuable C2‐fluoroalkyl functionalized pyridines. Moreover, the method was successfully applied to the reaction with P‐centered radicals. The utility of this transformation was further demonstrated by the late‐stage functionalization of complex bioactive molecules.
Remote migration: The photocatalyzed ortho‐selective migration on a pyridyl ring has been achieved for the site‐selective trifluoromethylative pyridylation of unactivated alkenes under mild reaction conditions. Notably, this method could be successfully extended to tertiary radicals to forge quaternary C centers bearing C2‐substituted pyridyl groups, overriding the commonly observed preference for the C4 addition.
Display omitted
•This paper summarized 159 natural compounds against ALI.•The paper summed up the protective effects of all products on ALI in vivo and vitro.•This paper clarified the underlying ...mechanism of natural compounds against ALI.
Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS) as common life-threatening lung diseases with high mortality rates are mostly associated with acute and severe inflammation in lungs. With increasing in-depth studies of ALI/ARDS, significant breakthroughs have been made, however, there are still no effective pharmacological therapies for treatment of ALI/ARDS. Especially, the novel coronavirus pneumonia (COVID-19) is ravaging the globe, and causes severe respiratory distress syndrome. Therefore, developing new drugs for therapy of ALI/ARDS is in great demand, which might also be helpful for treatment of COVID-19. Natural compounds have always inspired drug development, and numerous natural products have shown potential therapeutic effects on ALI/ARDS. Therefore, this review focuses on the potential therapeutic effects of natural compounds on ALI and the underlying mechanisms. Overall, the review discusses 159 compounds and summarizes more than 400 references to present the protective effects of natural compounds against ALI and the underlying mechanism.
Recently, quantum anomalous Hall effect with spontaneous ferromagnetism was observed in twisted bilayer graphenes (TBG) near 3/4 filling. Importantly, it was observed that an extremely small current ...can switch the direction of the magnetization. This offers the prospect of realizing low energy dissipation magnetic memories. However, the mechanism of the current-driven magnetization switching is poorly understood as the charge currents in graphenes are generally believed to be non-magnetic. In this work, we demonstrate that in TBG, the twisting and substrate induced symmetry breaking allow an out of plane orbital magnetization to be generated by a charge current. Moreover, the large Berry curvatures of the flat bands give the Bloch electrons large orbital magnetic moments so that a small current can generate a large orbital magnetization. We further demonstrate how the charge current can switch the magnetization of the ferromagnetic TBG near 3/4 filling as observed in the experiments.
PDF
