Search

Neuropathic pain can occur during the prediabetic stage, even in the absence of hyperglycemia. The presence of prediabetic neuropathic pain (PDNP) poses challenges to the management of individuals with prediabetes. However, the mechanisms underlying this pain remain unclear. This study aims to investigate the underlying mechanism and identify potential therapeutic targets of PDNP. A prediabetic animal model induced by a high‐energy diet exhibits both mechanical allodynia and thermal hyperalgesia. Furthermore, hyperexcitability and decreased potassium currents are observed in the dorsal root ganglion (DRG) neurons of these rats. TREK1 and TREK2 channels, which belong to the two‐pore‐domain K+ channel (K2P) family and play an important role in controlling cellular excitability, are downregulated in DRG neurons. Moreover, this alteration is modulated by Sortilin, a molecular partner that modulates the expression of TREK1. The overexpression of Sortilin negatively affects the expression of TREK1 and TREK2, leading to increased neuronal excitability in the DRG and enhanced peripheral pain sensitivity in rats. Moreover, the downregulation of Sortilin or activation of TREK1 and TREK2 channels by genetic or pharmacological approaches can alleviate PDNP. Therefore, targeting the Sortilin‐mediated TREK1/2 pathway may provide a therapeutic approach for ameliorating PDNP. [ABSTRACT FROM AUTHOR]

Achieving circularly polarized organic ultralong room‐temperature phosphorescence (CP‐OURTP) with a high luminescent dissymmetry factor (glum) is crucial for diverse optoelectronic applications. In particular, dynamically controlling the dissymmetry factor of CP‐OURTP can profoundly advance these applications, but it is still unprecedented. This study introduces an effective strategy to achieve photoirradiation‐driven chirality regulation in a bilayered structure film, which consists of a layer of soft helical superstructure incorporated with a light‐driven molecular motor and a layer of room‐temperature phosphorescent (RTP) polymer. The prepared bilayered film exhibits CP‐OURTP with an emission lifetime of 805 ms and a glum value up to 1.38. Remarkably, the glum value of the resulting CP‐OURTP film can be reversibly controlled between 0.6 and 1.38 over 20 cycles by light irradiation, representing the first example of dynamically controlling the glum in CP‐OURTP. [ABSTRACT FROM AUTHOR]

Geographical variation in species richness in plant groups is determined by the interplay between historical, evolutionary, and ecological processes. However, the processes underlying the striking disparity in species richness between Asia and the Americas remain poorly understood. Here, we synthesize global phylogenetic and macroecological data on the diversification of Smilacaceae, deciphering potential drivers underlying the species diversity pattern biased toward Asia. We compiled global distributions of all Smilacaceae species, and reconstructed the biogeographic history and niche evolution using a new time‐calibrated phylogeny (eight genes, 135 species). Integrating these data sets, we estimated evolutionary histories and diversification rates for each region, and tested correlations among species diversification, niche evolution, and niche divergence. Smilacaceae probably originated during the Late Cretaceous/Early Palaeocene and began to diversify in middle to low latitudes in Central America and Eurasia during the Late Eocene. Both the Old and New World clades exhibited a steady, albeit slight, increase of species diversification from the Late Eocene to Early Miocene. However, the Old World clade experienced an abrupt increase in net diversification during the Late Miocene. Our findings also revealed that species diversification rates were positively correlated with ecological niche evolution and niche divergence. Niche shifts and climatic niche evolution since the Middle Miocene played crucial roles in species diversification dynamics within Smilacaceae. The high plant richness in Asia may be explained by greater diversification in this region, potentially promoted by heterogeneous environments. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) micro/nanolasers hold great potential for integration of optoelectronic circuitry, medical diagnosis, sensing, and so forth. For the laser medium, organic gain molecules are highly attractive in NIR micro/nanolasers due to the inherent merits of abundant excited‐state processes, chemical tunability, and solution processing. Herein, the recent advances of NIR organic micro/nanolasers on nondoped molecule aggregates are reviewed from the aspects of gain materials, fabrication of self‐assembled microcavities, and NIR lasing actions, as well as some typical examples in applications, supporting the effective construction of internal quantitative relationship of gain molecular structures, excited‐state gain processes, self‐assembled micro/nanostructures, and NIR lasing performance. Finally, conclusion and outlook are given, aiming at offering valuable revelation for further development of high‐performance NIR organic micro/nanolasers. [ABSTRACT FROM AUTHOR]

Organic semiconductor molecules possess chemical tunability and large stimulated emission cross section, representing a promising candidate for laser gain medium. However, for the pursuit of telecom‐wavelength organic lasers, one of the major obstacles is the lack of effective energy‐level systems with high optical gain to compensate the exciton deactivation losses. Herein, the effects of molecular conformation‐dependent distinct cascaded proton‐transfer six‐level energy gain systems on lasing emission properties are systematically investigated based on organic polymorphs, proving that an energy‐level gain system without reversible transition channels is more conducive to the formation of efficient population inversion and high optical gain. Notably, the one‐way irreversible six‐level energy system of β‐phase polymorph supports more favorable population inversions than the two‐way reversible six‐level system of α‐phase polymorph due to the irreversible excited‐state second proton transfer and the irreversible ground‐state recovery, achieving the amplified spontaneous emission at telecom‐wavelength of ≈850 nm. This study provides useful guidelines for constructing efficient energy‐level gain systems, promoting the exploration of high‐gain organic semiconductor laser materials from visible to near‐infrared region. [ABSTRACT FROM AUTHOR]

Wound healing is a complex and error‐prone process. Wound healing in adults often leads to the formation of scars, a type of fibrotic tissue that lacks skin appendages. Hypertrophic scars and keloids can also form when the wound‐healing process goes wrong. Leptin (Lep) and leptin receptors (LepRs) have recently been shown to affect multiple stages of wound healing. This effect, however, is paradoxical for scarless wound healing. On the one hand, Lep exerts pro‐inflammatory and profibrotic effects; on the other hand, Lep can regulate hair follicle growth. This paper summarises the role of Lep and LepRs on cells in different stages of wound healing, briefly introduces the process of wound healing and Lep and LepRs, and examines the possibility of promoting scarless wound healing through spatiotemporal, systemic, and local regulation of Lep levels and the binding of Lep and LepRs. [ABSTRACT FROM AUTHOR]

Organic gain materials, with the merit of abundant excited‐state processes with large stimulated emission cross‐section, show considerable potential in lasers. The abundant excited‐state processes provide excellent platform for the construction of various forms of energy‐level systems, based on which the efficient population inversion and the tailorable gain region are supported. Herein, the development of organic lasers with distinctive energy‐level systems is summarized according to the classification of excited‐state gain processes including singlet quasi‐four‐level transition, energy transfer, excimer, charge transfer (CT), excited‐state intramolecular proton transfer (ESIPT), and some other novel photophysical processes, giving deep insight into the inherent relationship between energy‐level systems and laser action. Finally, the challenges and perspectives for the future development are presented, hopefully to offer valuable enlightenment for the further optimization of energy‐level systems toward high‐gain organic lasers including electrically pumped organic lasers. [ABSTRACT FROM AUTHOR]

Organic molecules which can undergo excited‐state intramolecular proton transfer (ESIPT) process have been considered as ideal gain materials for near‐infrared organic lasers owing to their effective four‐level systems. However, extending lasing wavelength beyond 800 nm with present ESIPT‐active gain materials is still in challenge. Herein, we established a molecular design strategy that operates via extending the π‐conjugated system of the ESIPT parent core to enhance the cascaded double ESIPT process and thus to achieve the red‐shifted six‐level system lasing. Concretely, a model molecule with 1,9‐dihydroxyanthracene as the ESIPT parent core was designed and synthesized, which was proved to undergo twice cascaded ESIPT processes while the 1,8‐dihydroxynaphthalene‐based analogue can only undergo once ESIPT process based on DFT calculations and ultrafast dynamics analyses. Finally, a six‐level system lasing toward 900 nm was achieved with a low threshold of 27.4 μJ cm−2. [ABSTRACT FROM AUTHOR]

Disturbances or defects in the process of wound repair can disrupt the delicate balance of cells and molecules necessary for complete wound healing, thus leading to chronic wounds or fibrotic scars. Myofibroblasts are one of the most important cells involved in fibrotic scars, and reprogramming provides a potential avenue to increase myofibroblast clearance. Although myofibroblasts have long been recognized as terminally differentiated cells, recent studies have shown that myofibroblasts have the capacity to be reprogrammed into adipocytes. This review intends to summarize the potential of reprogramming myofibroblasts into adipocytes. We will discuss myofibroblast lineage tracing, as well as the known mechanisms underlying adipocyte regeneration from myofibroblasts. In addition, we investigated different changes in myofibroblast gene expression, transcriptional regulators, signalling pathways and epigenetic regulators during skin wound healing. In the future, myofibroblast reprogramming in wound healing will be better understood and appreciated, which may provide new ideas for the treatment of scarless wound healing. [ABSTRACT FROM AUTHOR]

Excited‐state intramolecular proton transfer (ESIPT)‐active organic semiconductor materials, characterized by a or several resonance‐assisted hydrogen bonds (RAHBs), are supposed to be ideal candidates for achieving high‐performance near‐infrared (NIR) lasers. However, according to the energy gap law, the development of ESIPT‐active gain materials is still limited by the serious nonradiative decays. Herein, it is demonstrated that RAHBs can activate ESIPT lasing by inhibiting nonradiative decays. A new ESIPT‐active material 1,5‐dihydroxy‐2,6‐diphenylanthraquinone (DP‐DHAQ) containing two centrosymmetric RAHBs is developed, which exhibits a ≈100‐fold higher radiative decay rate (kr = 1.1 × 1010 s–1) in doped polystyrene (PS) film than that of 1‐hydroxy‐5‐methoxy‐2,6‐diphenylanthraquinone (DP‐HMAQ) and 1,5‐dimethoxy‐2,6‐diphenylanthraquinone (DP‐DMAQ), in which one and two RAHBs are broken, respectively, by introducing methyl groups. Both DP‐DHAQ and DP‐HMAQ can form four‐level systems based on the ESIPT processes, but only DP‐DHAQ doped PS microspheres exhibit laser emission at 710 nm under the test conditions. It is worth mentioning that single‐crystal microplates of DP‐DHAQ can realize NIR laser emission at 725 nm. The results suggest that RAHBs can effectively activate the gain property of ESIPT‐active materials, which deepens insights into NIR ESIPT lasing and provides a new proposal for the design of organic laser‐active molecules. [ABSTRACT FROM AUTHOR]

The loss of dermal white adipose tissue (dWAT) is vital to the formation of dermal fibrosis (DF), but the specific mechanism is not well understood. A few studies are reviewed to explore the role of dWAT in the formation of DF. Recent findings indicated that the adipocytes‐to‐myofibroblasts transition in dWAT reflects the direct contribution to the DF formation. While adipose‐derived stem cells (ADSCs) contained in dWAT express antifibrotic cytokines, the loss of ADSCs leads to skin protection decreased, which indirectly exacerbates DF and tissue damage. Therefore, blocking or reversing the adipocytes‐to‐myofibroblasts transition or improving the survival of ADSCs in dWAT and the expression of antifibrotic cytokines may be an effective strategy for the treatment of DF. [ABSTRACT FROM AUTHOR]

Organic single crystals have attracted great attention for solid‐state lasers owing to their smooth morphologies with inherent optical microcavity, ordered molecular packing mode with minimized defects density, and high photoluminescence quantum efficiency. However, the organic single‐crystal lasers, including whispering‐gallery‐mode (WGM) lasers with nondirectional emission and Fabry–Perot (F–P) lasers with inherent high‐lasing threshold, cannot achieve state‐of‐the‐art performance. Herein, the hierarchical self‐assembly of organic single‐crystal heterostructures made from cube‐shaped microdisks with optical gain and microwires with optical waveguide characteristics is demonstrated, which realize the unidirectional WGM laser action with a low‐lasing threshold of ≈600 nJ cm−2. The lattice mismatch rate principle contributes to the growth of these single‐crystal organic heterostructures. More significantly, the waveguide‐coupled WGM microcavity with a coupling coefficient of 28.8% proves that the unidirectional outcoupling of the single‐crystal WGM lasers from the single‐crystal wire waveguides is achieved. The results will pave an alternative avenue for high‐performance organic single‐crystal lasers. [ABSTRACT FROM AUTHOR]

We investigated the material properties of Cremonese soundboards using a wide range of spectroscopic, microscopic, and chemical techniques. We found similar types of spruce in Cremonese soundboards as in modern instruments, but Cremonese spruces exhibit unnatural elemental compositions and oxidation patterns that suggest artificial manipulation. Combining analytical data and historical information, we may deduce the minerals being added and their potential functions—borax and metal sulfates for fungal suppression, table salt for moisture control, alum for molecular crosslinking, and potash or quicklime for alkaline treatment. The overall purpose may have been wood preservation or acoustic tuning. Hemicellulose fragmentation and altered cellulose nanostructures are observed in heavily treated Stradivari specimens, which show diminished second‐harmonic generation signals. Guarneri's practice of crosslinking wood fibers via aluminum coordination may also affect mechanical and acoustic properties. Our data suggest that old masters undertook materials engineering experiments to produce soundboards with unique properties. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) organic solid‐state lasers play an essential role in applications ranging from laser communication to infrared night vision, but progress in this area is restricted by the lack of effective excited‐state gain processes. Herein, we originally proposed and demonstrated the cascaded occurrence of excited‐state intramolecular proton transfer for constructing the completely new energy‐level systems. Cascading by the first ultrafast proton transfer of <430 fs and the subsequent irreversible second proton transfer of ca. 1.6 ps, the stepwise proton transfer process favors the true six‐level photophysical cycle, which supports efficient population inversion and thus NIR single‐mode lasing at 854 nm. This work realizes longest wavelength beyond 850 nm of organic single‐crystal lasing to date and originally exploits the cascaded excited‐state molecular proton transfer energy‐level systems for organic solid‐state lasers. [ABSTRACT FROM AUTHOR]

The incidence of acute and chronic wound diseases is rising due to various reasons. With complicated pathogenesis, long course, difficult treatment and high disability, wound diseases have become a major burden for patients, their families, and society. Therefore, the focus of research is to identify new ideas and methods for treatment. Fat grafting has gained increased attention because of its effectiveness in wound treatment, and further analysis has uncovered that the stem cells derived from fat may be the main factor affecting wound healing. We summarize the function of adipose stem cells and analyze their possible mechanisms in tissue repair, helping to provide new ideas for the treatment of wound healing. [ABSTRACT FROM AUTHOR]

The deterministic manufacturing and patterning of high‐quality organic single crystal semiconductors are core opportunities and challenges for large‐scale integrated functional devices with high efficiency and high performance. As for the solution patterning for the fabrication of the organic semiconductors, various methods are reported to efficiently control the position, alignment, and size of organic structures. Nevertheless, the poor control of the dewetting dynamics of organic solution leads to the low crystallinity and disordered crystallographic orientation of as‐fabricated organic architectures, which can limit their device performance. Herein, by use of the micropillar‐structured template with asymmetric wettability, the patterned organic 1D single crystals with precise position and geometry, flat morphology, and high alignment can be constructed. Moreover, the nanowire arrays are demonstrated with active optical waveguiding. In addition, the other patterned architectures of circle, triangle, square, pentagon, and hexagon shapes can also be constituted by regulating the surface geometry of substrates. This work not only facilitates the fundamental understanding on the patterning and crystallization of organic architectures, but also contributes greatly to the development of large‐scale assembly technology for patterning micro/nanostructures. [ABSTRACT FROM AUTHOR]

N6‐methyladenosine (m6A) is one of the most abundant messenger RNA (mRNA) modifications in eukaryotes and is involved in various key processes of RNA metabolism. In this issue of Nature, Ries et al (2019) described the fundamental features of m6A modification of mRNAs in regulating the composition of the phase‐separated transcriptome on the basis of number and distribution, and provide strong evidence that m6A plays a role in regulating phase separation in cells. [ABSTRACT FROM AUTHOR]

Abstract: Organic cocrystals formed with two or more different molecules through intermolecular noncovalent interactions, such as π–π interaction and hydrogen/halogen bonds, have received increasing attention due to their promising applications in organic optoelectronics. For organic photonics and electronics, the growth morphology of organic micro/nanocrystals coupled with their shape and emission color is of great importance. In this study, using a “cocrystal” approach, the organic microcrystals can be modulated from the yellow‐emissive polyhedral microcrystals of 1,4‐bis (4‐cyanostyryl) benzene (p‐BCB) to the sky‐blue‐emissive microwires of p‐BCB:1,4‐diiodo tetrafluorobenzene (p‐BCB:DIFB), which are self‐assembled in solution at room temperature. Additionally, with the formation of the cocrystals, the radiative decay (kr) rate of these organic microcrystals is enhanced from 0.04 to 0.12 ns−1, which is attributed to the absence of excimers in the organic cocrystals. Therefore, this “cocrystal” approach can simultaneously tune the emission color, morphology, and molecular packing mode of these as‐prepared organic microcrystals, which can contribute to the development of organic integrated optoelectronic devices. [ABSTRACT FROM AUTHOR]

ICP-MS, um die einzigartige Mineralienrezeptur zu identifizieren, die Antonio Stradivari zur Behandlung seines Fichtenholzes, des Materials für die Geigendecke, verwendete. Keywords: cultural heritage; ICP-MS; IR spectroscopy; NMR spectroscopy; X-ray absorption spectroscopy EN cultural heritage ICP-MS IR spectroscopy NMR spectroscopy X-ray absorption spectroscopy 1 1 1 08/19/21 20210823 NES 210823 B Heritage Science b Im Forschungsartikel auf S. 19293 nutzen Hwan-Ching Tai et al. [Extracted from the article]

Organic heterostructures have been demonstrated to be excellent candidates for application in photonic components such as modulators and optical switches, but the controllable fabrication of organic heterostructures remains a considerable challenge due to the lattice mismatch and weak intermolecular forces. In this study, a photochromic strategy is demonstrated to fabricate in‐series organic heterostructures with high controllability and designability by selectively covering a portion of the organic microcrystals. Radiative energy transfer is found in the blue‐green fluorescent 2‐block of the organic heterostructure, which acts as the basic component unit, leading to the unique passive/active mixed waveguide mode. Furthermore, optical waveguides with switchable output light wavelength‐bands can be constructed based on the 3‐block and 5‐block heterostructures. By changing the input ports on the heterostructures, the blue, blue/green, or green wavelength band can be selectively outcoupled, thus indicating the potential of the organic heterostructures to be utilized in future photonic systems. [ABSTRACT FROM AUTHOR]

L‐type voltage‐gated calcium ion channels (L‐VGCCs) have been demonstrated to be the mediator of several significant intracellular activities in excitable cells, such as neurons, chromaffin cells and myocytes. Recently, an increasing number of studies have investigated the function of L‐VGCCs in non‐excitable cells, particularly stem cells. However, there appear to be no systematic reviews of the relationship between L‐VGCCs and stem cells, and filling this gap is prescient considering the contribution of L‐VGCCs to the proliferation and differentiation of several types of stem cells. This review will discuss the possible involvement of L‐VGCCs in stem cells, mainly focusing on osteogenesis mediated by mesenchymal stem cells (MSCs) from different tissues and neurogenesis mediated by neural stem/progenitor cells (NSCs). Additionally, advanced applications that use these channels as the target for tissue engineering, which may offer the hope of tissue regeneration in the future, will also be explored. [ABSTRACT FROM AUTHOR]

N6-methyladenosine (m 6 A) is one of the most abundant messenger RNA (mRNA) modifications in eukaryotes and is involved in various key processes of RNA metabolism. In this issue of Nature, Ries et al (2019) described the fundamental features of m6A modification of mRNAs in regulating the composition of the phase-separated transcriptome on the basis of number and distribution, and provide strong evidence that m6A plays a role in regulating phase separation in cells., (© 2019 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)