Catalytic Epoxidation of Carbonyl Compounds via Carbonyl Ylides: from Racemic to Enantioselective.

Transition-metal-catalyzed epoxidation of carbonyl compounds through carbonyl ylides represents a highly effective method for synthesizing a diverse range of valuable epoxides. This review offers an in-depth overview of the latest developments in inter- and intramolecular epoxidation reactions involving metal carbenes and carbonyl compounds, encompassing both racemic to enantioselective transformations. These catalytic epoxidations are reviewed by highlighting their product selectivity, diversity and applicability, and the related mechanistic rationale is showcased where possible.

Copper-Catalyzed [2 + 2] Cyclization/Ring Expansion of Ene-Ynamides: Construction of Medium- and Large-Sized Rings.

Catalytic cyclization of enynes is an efficient approach for the preparation of cyclic compounds, and a large variety of four- to six-membered rings could be synthesized using this method. However, it has been rarely employed for the construction of medium- and large-sized rings. Herein, we describe a copper-catalyzed cycloisomerization of ene-ynamides through a [2 + 2] cyclization/electrocyclic ring opening cascade, leading to the atom-economical assembly of indole-fused medium- and large-sized rings in moderate to excellent yields under mild reaction conditions. Importantly, the synthetic utility of this reaction was demonstrated by the convenient synthesis of iprindole.

The GFPT2-O-GlcNAcylation-YBX1 axis promotes IL-18 secretion to regulate the tumor immune microenvironment in pancreatic cancer.

The immunosuppressive microenvironment caused by several intrinsic and extrinsic mechanism has brought great challenges to the immunotherapy of pancreatic cancer. We identified GFPT2, the key enzyme in hexosamine biosynthesis pathway (HBP), as an immune-related prognostic gene in pancreatic cancer using transcriptome sequencing and further confirmed that GFPT2 promoted macrophage M2 polarization and malignant phenotype of pancreatic cancer. HBP is a glucose metabolism pathway leading to the generation of uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), which is further utilized for protein O-GlcNAcylation. We confirmed GFPT2-mediated O-GlcNAcylation played an important role in regulating immune microenvironment. Through cellular proteomics, we identified IL-18 as a key downstream of GFPT2 in regulating the immune microenvironment. Through CO-IP and protein mass spectrum, we confirmed that YBX1 was O-GlcNAcylated and nuclear translocated by GFPT2-mediated O-GlcNAcylation. Then, YBX1 functioned as a transcription factor to promote IL-18 transcription. Our study elucidated the relationship between the metabolic pathway of HBP in cancer cells and the immune microenvironment, which might provide some insights into the combination therapy of HBP vulnerability and immunotherapy in pancreatic cancer.

Enantioselective functionalization of unactivated C(sp3)-H bonds through copper-catalyzed diyne cyclization by kinetic resolution.

Site- and stereoselective C-H functionalization is highly challenging in the synthetic chemistry community. Although the chemistry of vinyl cations has been vigorously studied in C(sp3)-H functionalization reactions, the catalytic enantioselective C(sp3)-H functionalization based on vinyl cations, especially for an unactivated C(sp3)-H bond, has scarcely explored. Here, we report an asymmetric copper-catalyzed tandem diyne cyclization/unactivated C(sp3)-H insertion reaction via a kinetic resolution, affording both chiral polycyclic pyrroles and diynes with generally excellent enantioselectivities and excellent selectivity factors (up to 750). Importantly, this reaction demonstrates a metal-catalyzed enantioselective unactivated C(sp3)-H functionalization via vinyl cation and constitutes a kinetic resolution reaction based on diyne cyclization. Theoretical calculations further support the mechanism of vinyl cation-involved C(sp3)-H insertion reaction and elucidate the origin of enantioselectivity.

Fear of cancer recurrence and associated factors in family caregivers of patients with hematologic malignancy receiving chemotherapy: A latent profile analysis.

Objective: This study identified the potential subgroups of fear of cancer recurrence (FCR) in family caregivers (FCs) of patients with hematologic malignancies receiving chemotherapy, as well as exploring factors associated with subgroups. Methods: This was a cross-sectional study involving 206 pairs of participating patients with hematologic malignancies receiving chemotherapy and their FCs. Using Mplus 8.3 to perform the latent profile analysis of FCs' FCR, the FCs' burden, quality of life, psychological resilience, and anxiety as well as their demographic characteristics were compared between the subgroups, with a logistic regression analysis being applied to examine the factors associated with the FCR subgroups. Results: A total of 206 FCs were classified into two subgroups: "a low level of FCR" (Class 1, 65.4%) and "a high level of FCR" (Class 2, 34.6%). Quality of life, anxiety, and frequency of chemotherapy were significantly associated with the two subgroups. Conclusions: FCs of patients with hematologic malignancy receiving chemotherapy had two FCR subgroups, "a low level of FCR" and "a high level of FCR", in association with quality of life, anxiety, and frequency of chemotherapy. These findings provide the theoretical foundations for screening the FCR factor of FCs and conducting interventions for them.

Gold Catalysis, Asymmetric Friedel-Crafts Alkylation Cascade for One-Pot Synthesis of Chiral Dihydrocarbazoles and Dihydrodibenzofurans.

A one-pot gold-catalyzed acyl migration followed by ytterbium-catalyzed asymmetric Friedel-Crafts alkylation is disclosed, leading to the rapid synthesis of chiral dihydrocarbazoles and dihydrodibenzofuran in generally moderate to good overall yields with good to excellent enantioselectivities. The gold-catalyzed acyl migration of propargyl acetates generates α-ylidene-ß-diketones with high E/Z ratios, which are then subjected to the ytterbium-catalyzed asymmetric Friedel-Crafts alkylation without any purification. Importantly, this protocol provides a new type of substrate for asymmetric Friedel-Crafts alkylation.

Green Printing for Scalable Organic Photovoltaic Modules by Controlling the Gradient Marangoni Flow.

Despite the rapid development in the performances of organic solar cells (OSCs), high-performance OSC modules based on green printing are still limited. The severe Coffee-ring effect (CRE) is considered to be the primary reason for the nonuniform distribution of active layer films. To solve this key printing problem, the cosolvent strategy is presented to deposit the active layer films. The guest solvent Mesitylene with a higher boiling point and a lower surface tension is incorporated into the host solvent o-XY to optimize the rheological properties, such as surface tension and viscosity of the active layer solutions. And the synergistic effect of inward Marangoni flow generation and solution thickening caused by the cosolvent strategy can effectively restrain CRE, resulting in highly homogeneous large-area active layer films. In addition, the optimized crystallization and phase separation of active layer films effectively accelerate the charge transport and exciton dissociation of devices. Consequently, based on PM6:BTP-eC9 system, the device prepared with the co-solvent strategy shows the a power conversion efficiency of 17.80%. Moreover, as the effective area scales to 1 and 16.94 cm2, the recorded performances are altered to 16.71% and 14.58%. This study provides a universal pathway for the development of green-printed high-efficiency organic photovoltaics.

MISNet: multi-source information-shared EEG emotion recognition network with two-stream structure.

Introduction: When constructing machine learning and deep neural networks, the domain shift problem on different subjects complicates the subject independent electroencephalography (EEG) emotion recognition. Most of the existing domain adaptation methods either treat all source domains as equivalent or train source-specific learners directly, misleading the network to acquire unreasonable transfer knowledge and thus resulting in negative transfer. Methods: This paper incorporates the individual difference and group commonality of distinct domains and proposes a multi-source information-shared network (MISNet) to enhance the performance of subject independent EEG emotion recognition models. The network stability is enhanced by employing a two-stream training structure with loop iteration strategy to alleviate outlier sources confusing the model. Additionally, we design two auxiliary loss functions for aligning the marginal distributions of domain-specific and domain shared features, and then optimize the convergence process by constraining gradient penalty on these auxiliary loss functions. Furthermore, the pre-training strategy is also proposed to ensure that the initial mapping of shared encoder contains sufficient emotional information. Results: We evaluate the proposed MISNet to ascertain the impact of several hyper-parameters on the domain adaptation capability of network. The ablation experiments are conducted on two publically accessible datasets SEED and SEED-IV to assess the effectiveness of each loss function. Discussion: The experimental results demonstrate that by disentangling private and shared emotional characteristics from differential entropy features of EEG signals, the proposed MISNet can gain robust subject independent performance and strong domain adaptability.

Recently reported cell migration inhibitors: Opportunities and challenges for antimetastatic agents.

Antimetastatic agents are highly desirable for cancer treatment because of the severe medical challenges and high mortality resulting from tumor metastasis. Having demonstrated antimetastatic effects in numerous in vitro and in vivo studies, migration inhibitors present significant opportunities for developing a new class of anticancer drugs. To provide a useful overview on the latest research in migration inhibitors, this article first discusses their therapeutic significance, targetable proteins, and developmental avenues. Subsequently it reviews over 20 representative migration inhibitors reported in recent journals in terms of their inhibitory mechanism, potency, and potential clinical utility. The relevance of the target proteins to cellular migratory function is focused on as it is crucial for assessing the overall efficacy of the inhibitors.

[Retracted] Potentiation of the antitumor activity of adriamycin against osteosarcoma by cannabinoid WIN­55,212­2.

[This retracts the article DOI: 10.3892/ol.2015.3525.].

Strong Oxidizing Molten Salts for Strengthening Structural Restoration Enabling Direct Regeneration of Spent Layered Cathode.

As a mainstream technology for recycling spent lithium-ion batteries, direct regeneration is rapidly developed due to its high efficiency and green characteristics. However, efficient reuse of spent LiNix Coy Mn1- x - y O2 cathode is still a significant challenge, as the rock salt/spinel phase on the surface hinders the Li replenishment and phase transformation to the layered structure. In this work, the fundamental understanding of the repair mechanism is confirmed that the oxidizing atmosphere is the crucial factor that can greatly improve the rate and degree of phase restoration. Particularly, a ternary-component molten salt system (LiOH-Li2 CO3 -LiNO3 ) is proposed for direct regeneration of LiNi0.5 Co0.2 Mn0.3 O2 (NCM523), which can in situ generate the strong oxidizing intermediate of superoxide radicals. Additionally, it shows a liquid-like reaction environment at a lower temperature to acceclerate the transport rate of superoxide-ions. Therefore, the synergistic effect of LiOH-Li2 CO3 -LiNO3 system can strengthen the full restoration of rock salt/spinel phases and achieve the complete Li-supplement. As anticipated, the regenerated NCM523 delivers a high cycling stability with a retention of 91.7% after 100 cycles, which is even competitive with the commercial NCM523. This strategy provides a facile approach for the complete recovery of layer structure cathode, demonstrating a unique perspective for the direct regeneration of spent lithium-ion batteries.

Nucleophile-Controlled Trapping of Gold Carbene by Nitriles and Water: Synthesis of 5H-Pyrimido[5,4-b]indoles and 2-Benzylidene-3-indolinones.

A gold-catalyzed, nucleophile-controlled cascade reaction of N-(2-azidophenyl-ynyl)methanesulfonamides with nitriles and water is described that provides structurally diverse 5H-pyrimido[5,4-b]indoles and 2-benzylidene-3-indolinones in good to excellent yields. Mechanistic studies indicate that the ß-sulfonamido-α-imino gold carbene is the key intermediate which is generated through the gold-catalyzed cyclization of N-(2-azidophenyl-ynyl)methanesulfonamides and undergoes formal [4 + 2] cascade annulation with nitriles and intramolecular SN2' type reaction with water, respectively.

Regulating Crystallinity Mismatch Between Donor and Acceptor to Improve Exciton/Charge Transport in Efficient Organic Solar Cells.

Achieving a more balanced charge transport by morphological control is crucial in reducing bimolecular and trap-assisted recombination and enhancing the critical parameters for efficient organic solar cells (OSCs). Hence, a facile strategy is proposed to reduce the crystallinity difference between donor and acceptor by incorporating a novel multifunctional liquid crystal small molecule (LCSM) BDTPF4-C6 into the binary blend. BDTPF4-C6 is the first LCSM based on a tetrafluorobenzene unit and features a low liquid crystal phase transition temperature and strong self-assembly ability, conducive to regulating the active layer morphology. When BDTPF4-C6 is introduced as a guest molecule into the PM6 : Y6 binary, it exhibits better compatibility with the donor PM6 and primarily resides within the PM6 phase because of the similarity-intermiscibility principle. Moreover, systematic studies revealed that BDTPF4-C6 could be used as a seeding agent for PM6 to enhance its crystallinity, thereby forming a more balanced and favourable charge transport with suppressed charge recombination. Intriguingly, dual Förster resonance energy transfer was observed between the guest molecule and the host donor and acceptor, resulting in an improved current density. This study demonstrates a facile approach to balance the charge mobilities and offers new insights into boosting the efficiency of single-junction OSCs beyond 20 %.

Plasma circRNA HIPK2 as a putative biomarker for the diagnosis and prediction of therapeutic effects in major depressive disorder.

BACKGROUND: Circular RNAs (circRNAs) are a prevalent type of non-coding RNAs exhibiting extensive expression in mammalian cells. Owing to their involvement in diverse pathophysiological mechanisms of major depressive disorder (MDD) and their inherent stability in peripheral blood, circRNAs have emerged as potential biomarkers of considerable significance. This study aimed to identify and validate circular RNA HIPK2 (circHIPK2) in MDD patients and to investigate its potential as a biomarker for the diagnosis and prognosis of MDD. METHODS: Patients with MDD (n = 81) and healthy controls (HCs) (n = 48) were recruited for our study (October 2022 to June 2023). The expression of circHIPK2 in plasma was assessed using absolute quantitative polymerase chain reaction (qPCR). RESULTS: The expression of circHIPK2 in plasma of patients with MDD exhibited a significant increase compared to HCs. The circHIPK2 levels showed an area under the curve (AUC) of 0.796, corresponding to a specificity of 97.9% and a sensitivity of 60.4% in diagnosing MDD. Additionally, the rate of change in circHIPK2 over a 14-day period exhibited an AUC curve of 0.819, indicating its predictive value for antidepressive effects. CONCLUSIONS: CircHIPK2 could serve as a potential biomarker for diagnosing MDD and predicting therapeutic effects of MDD.

A Dual-Polythiophene Blending Strategy to Reduce the Efficiency-Stability-Cost Gap of Solar Cells.

Benefiting from the photovoltaic material innovation and delicate device optimization, high-efficiency solar cells employing polymeric materials are thriving. Reducing the gap of cost, efficiency, and stability is the critical challenge faced by the emerging solar cells such as organics, quantum dots and perovskites. Poly(3-alkylthiophene) demonstrates great potential in organic solar cells and quantum dot solar cells as the active layer or the hole transport layer due to its large scalability, excellent photoelectric performance, and favorable hydrophobicity. The present low efficiency and insufficient stability, restrict its commercial application. In this work, a facile strategy of blending two simple polythiophenes is put forward to manipulate the film microstructure and enhance the device efficiency and thermal stability of solar cells. The introduction of P3PT can improve the power conversion efficiency (PCE) of a benchmark cost-effective blend P3HT:O-IDTBR to 7.41%, and the developed ternary solar cells also exhibit increased thermal stability. More strikingly, the quantum dot solar cells with the dual-polythiophene hole transport layer achieve the highest PCE of 10.51%, which is among the topmost efficiencies for quantum dots/polythiophene solar cells. Together, this work provides an effective route to simultaneously optimize the device efficiency and thermal stability of solar cells.

Regulating Phase Separation Kinetics for High-Efficiency and Mechanically Robust All-Polymer Solar Cells.

All-polymer solar cells (all-PSCs) possess excellent operation stability and mechanical robustness than other types of organic solar cells, thereby attracting considerable attention for wearable flexible electron devices. However, the power conversion efficiencies (PCEs) of all-PSCs are still lagging behind those of small-molecule-acceptor-based systems owing to the limitation of photoactive materials and unsatisfactory blend morphology. In this work, a novel terpolymer, denoted as PBDB-TFCl (poly4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo[1,2-b:4,5-b″]dithiophene-1,3-bis(2-ethylhexyl)-5,7-di(thiophen-2-yl)-4H,8H-benzo[1,2-c:4,5-c″]dithiophene-4,8-dione-4,8-bis(4-chloro-5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene), is used as an electron donor coupled with a ternary strategy to optimize the performance of all-PSCs. The addition of PBDB-TCl unit deepens the highest occupied molecular orbital energy level, reducing voltage losses. Moreover, the introduction of the guest donor (D18-Cl) effectively regulates the phase-transition kinetics of PBDB-TFCl:D18-Cl:PY-IT during the film formation, leading to ideal size of aggregations and enhanced crystallinity. PBDB-TFCl:D18-Cl:PY-IT devices exhibit a PCE of 18.6% (certified as 18.3%), judged as the highest value so far obtained with all-PSCs. Besides, based on the ternary active layer, the manufactured 36 cm2 flexible modules exhibit a PCE of 15.1%. Meanwhile, the ternary PSCs exhibit superior photostability and mechanical stability. In summary, the proposed strategy, based on molecular design and the ternary strategy, allows optimization of the all-polymer blend morphology and improvement of the photovoltaic performance for stable large-scale flexible PSCs.

Polymer-Entangled Spontaneous Pseudo-Planar Heterojunction for Constructing Efficient Flexible Organic Solar Cells.

Flexible organic solar cells (FOSCs) have attracted considerable attention from researchers as promising portable power sources for wearable electronic devices. However, insufficient power conversion efficiency (PCE), intrinsic stretchability, and mechanical stability of FOSCs remain severe obstacles to their application. Herein, an entangled strategy is proposed for the synergistic optimization of PCE and mechanical properties of FOSCs through green sequential printing combined with polymer-induced spontaneous gradient heterojunction phase separation morphology. Impressively, the toughened-pseudo-planar heterojunction (Toughened-PPHJ) film exhibits excellent tensile properties with a crack onset strain (COS) of 11.0%, twice that of the reference bulk heterojunction (BHJ) film (5.5%), which is among the highest values reported for the state-of-the-art polymer/small molecule-based systems. Finite element simulation of stress distribution during film bending confirms that Toughened-PPHJ film can release residual stress well. Therefore, this optimal device shows a high PCE (18.16%) with enhanced (short-circuit current density) JSC and suppressed energy loss, which is a significant improvement over the conventional BHJ device (16.99%). Finally, the 1 cm2 flexible Toughened-PPHJ device retains more than 92% of its initial PCE (13.3%) after 1000 bending cycles. This work provides a feasible guiding idea for future flexible portable power supplies.

Exosomal lncRNA NEAT1 Inhibits NK-Cell Activity to Promote Multiple Myeloma Cell Immune Escape via an EZH2/PBX1 Axis.

Exosomal long noncoding RNAs (lncRNA) derived from cancer cells are implicated in various processes, including cancer cell proliferation, metastasis, and immunomodulation. We investigated the role and underlying mechanism of exosome-transmitted lncRNA NEAT1 in the immune escape of multiple myeloma cells from natural killer (NK) cells. Multiple myeloma cells and samples from patients with multiple myeloma were obtained. The effects of multiple myeloma cell-derived exosomes (multiple myeloma exosomes) and exosomal NEAT1 on the functions of NK cells were evaluated using EdU staining, CCK-8, flow cytometry, and ELISA. Chromatin and RNA immunoprecipitation were performed to identify interactions between NEAT1, enhancer of Zeste Homolog 2 (EZH2), and pre-B-cell leukemia transcription factor 1 (PBX1). A xenograft tumor model was constructed to verify the effects of exosomal NEAT1 on tumor growth. qRT-PCR, Western blot analysis, and IHC were conducted to detect related genes. NEAT1 levels were upregulated in multiple myeloma tumor tissues, multiple myeloma cells, and multiple myeloma exosomes. Multiple myeloma exosomes suppressed cell proliferation, promoted apoptosis, reduced natural killer group 2, member D (NKG2D)-positive cells, and the production of TNFα) and interferon-gamma (IFN-γ) in NK cells, whereas NEAT1-silenced exosomes had little effect. NEAT1 silenced PBX1 by recruiting EZH2. PBX1 knockdown abrogated the effects of NEAT1-silenced exosomes on NK and multiple myeloma cells. NEAT1-silenced exosomes inhibited tumor growth in mice, decreased Ki67 and PD-L1, and increased NKG2D, TNFα, and IFNγ in tumor tissues. In summary, multiple myeloma cell-derived exosomal NEAT1 suppressed NK-cell activity by downregulating PBX1, promoting multiple myeloma cell immune escape. This study suggests a potential strategy for treating multiple myeloma. IMPLICATIONS: This study reveals that exosomal NEAT1 regulates EZH2/PBX1 axis to inhibit NK-cell activity, thereby promoting multiple myeloma cell immune escape, which offers a novel therapeutic potential for multiple myeloma.

Heterostructured MoO3 Anchored Defect-Rich NiFe-LDH/NF as a Robust Self-Supporting Electrocatalyst for Overall Water Splitting.

The rational design of inexpensive metal electrocatalysts with exciting catalytic activity for overall water splitting (OWS) remains a significant challenge. Heterostructures of NiFe layered double hydroxides (NiFe-LDHs) with abundant oxygen defects and tunable electronic properties have garnered considerable attention. Here, a self-supporting heterostructured catalyst (named MoO3/NiFe-NF) is synthesized via a hydrothermal method to grow NiFe-LDH with oxygen vacancies (OV) in situ on inexpensive nickel foam (NF). Subsequently, MoO3 is anchored and grown on the surface of NiFe-LDH by electrodeposition. The obtained catalysts achieved outstanding oxygen/hydrogen evolution reaction (OER/HER, 212 mV/85 mV@10 mA cm-2) performance in 1 m KOH. Additionally, when MoO3/NiFe-NF is utilized as the cathode and anode in OWS, a current density of 10 mA cm-2 can be obtained as an ultralow battery voltage of 1.43 V, a significantly lower value compared to the commercial electrolyzer incorporating Pt/C and IrO2 electrode materials. Finally, density functional theory (DFT) calculations and advanced spectroscopy technology are conducted to reveal the effects of heterojunctions and OV on the internal electronic structure of the electrical catalysts. Mainly, the present study provides a novel tactic for the rational design of remarkable, low-cost NiFe-LDH electrocatalysts with heterostructures for OWS.

Achieving Record-High Stretchability and Mechanical Stability in Organic Photovoltaic Blends with a Dilute-absorber Strategy.

Organic solar cells (OSCs) have potential for applications in wearable electronics. Except for high power conversion efficiency (PCE), excellent tensile properties and mechanical stability are required for achieving high-performance wearable OSCs, while the present metrics barely meet the stretchable requirements. Herein, this work proposes a facile and low-cost strategy for constructing intrinsically stretchable OSCs by introducing a readily accessible polymer elastomer as a diluent for all-polymer photovoltaic blends. Remarkably, record-high stretchability with a fracture strain of up to 1000% and mechanical stability with elastic recovery >90% under cyclic tensile tests are realized in the OSCs active layers for the first time. Specifically, the tensile properties of best-performing all-polymer photovoltaic blends are increased by up to 250 times after blending. Previously unattainable performance metrics (fracture strain >50% and PCE >10%) are achieved simultaneously for the resulting photovoltaic films. Furthermore, an overall evaluation parameter y is proposed for the efficiency-cost- stretchability balance of photovoltaic blend films. The y value of dilute-absorber system is two orders of magnitude greater than those of prior state-of-the-art systems. Additionally, intrinsically stretchable devices are prepared to showcase the mechanical stability. Overall, this work offers a new avenue for constructing and comprehensively evaluating intrinsically stretchable organic electronic films.