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PURPOSE: Revumenib, an oral, small molecule inhibitor of the menin-lysine methyltransferase 2A (KMT2A) interaction, showed promising efficacy and safety in a phase I study of heavily pretreated patients with KMT2A-rearranged (KMT2Ar) acute leukemia. Here, we evaluated the activity of revumenib in individuals with relapsed/refractory (R/R) KMT2Ar acute leukemia. METHODS: AUGMENT-101 is a phase I/II, open-label, dose-escalation and expansion study of revumenib conducted across 22 clinical sites in five countries (ClinicalTrials.gov identifier: NCT04065399). We report results from the phase II, registration-enabling portion. Individuals age ≥30 days with R/R KMT2Ar acute leukemia or with AML and nucleophosmin 1 (NPM1) mutation were enrolled. Revumenib was administered once every 12 hours, at 163 mg (95 mg/m2 if weight <40 kg) with a strong cytochrome P450 inhibitor, in 28-day cycles. The primary end points were the rate of complete remission (CR) or CR with partial hematologic recovery (CR + CRh) and safety. At a prespecified interim analysis, safety was assessed in all KMT2Ar treated patients; efficacy was assessed in those with centrally confirmed KMT2Ar. The separate NPM1 cohort of the trial is ongoing. RESULTS: From October 1, 2021, to July 24, 2023, N = 94 patients (median [range] age, 37 [1.3-75] years) were treated. Grade ≥3 adverse events included febrile neutropenia (37.2%), differentiation syndrome (16.0%), and QTc prolongation (13.8%). In the efficacy-evaluable patients (n = 57), the CR + CRh rate was 22.8% (95% CI, 12.7 to 35.8), exceeding the null hypothesis of 10% (P = .0036). Overall response rate was 63.2% (95% CI, 49.3 to 75.6), with 15 of 22 patients (68.2%) having no detectable residual disease. CONCLUSION: Revumenib led to high remission rates with a predictable safety profile in R/R KMT2Ar acute leukemia. To our knowledge, this trial represents the largest evaluation of a targeted therapy for these patients.
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BACKGROUND: Chest X-ray image classification for multiple diseases is an important research direction in the field of computer vision and medical image processing. It aims to utilize advanced image processing techniques and deep learning algorithms to automatically analyze and identify X-ray images, determining whether specific pathologies or structural abnormalities exist in the images. OBJECTIVE: We present the MMPDenseNet network designed specifically for chest multi-label disease classification. METHODS: Initially, the network employs the adaptive activation function Meta-ACON to enhance feature representation. Subsequently, the network incorporates a multi-head self-attention mechanism, merging the conventional convolutional neural network with the Transformer, thereby bolstering the ability to extract both local and global features. Ultimately, the network integrates a pyramid squeeze attention module to capture spatial information and enrich the feature space. RESULTS: The concluding experiment yielded an average AUC of 0.898, marking an average accuracy improvement of 0.6% over the baseline model. When compared with the original network, the experimental results highlight that MMPDenseNet considerably elevates the classification accuracy of various chest diseases. CONCLUSION: It can be concluded that the network, thus, holds substantial value for clinical applications.
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OBJECTIVES: This study evaluated the phase composition, phase transformation behaviour, and mechanical properties of five heat-treated NiTi instruments. METHODS: ProTaper NEXT (M-wire, PTN), ProTaper Gold (Gold-wire, PTG), One Curve (C-wire, OC), EdgeTaper Platinum (Fire-wire, ETP), NeoNiTi (electrical discharge machining-wire, NNA), and ProTaper Universal (conventional wire, PTU, control) with #25-tip size were tested (n = 12/group) for cyclic fatigue resistance (number of cycles to failure; NCF) and torsional resistance (angle of rotation to fracture and maximum torque at fracture [ultimate torsional strength]). The geometry and fracture surfaces of the tested instruments were examined by scanning electron microscopy. The phase transformation temperature and phase composition of the instruments were evaluated using differential scanning calorimetry and X-ray diffraction. Data were statistically analysed using one-way ANOVA and Tukey's post hoc test, with the significance level set at 5%. RESULTS: PTG showed the highest NCF (P < .05) at 37°C, while ETP exhibited the highest angle of rotation to fracture, ultimate torsional strength, and stiffness (P < .05). Scanning electron microscopy demonstrated typical clusters of fatigue striations and numerous cracks after cyclic fatigue fracture, whereas there was a concentric abrasion pattern with a dimple and microvoids at the centre after torsional fracture. In differential scanning calorimetry curves, austenite-finishing temperatures of heat-treated instruments were higher than 37°C, whereas that of PTU was lower than 37°C. PTU showed strong peaks of austenite at 25 and 37°C, whereas ETP showed a strong peak of R-phase at 25°C, but mostly austenite phase at 37°C in X-ray diffraction. CONCLUSIONS: Geometry, alloy type, and phase transformation temperatures of NiTi instruments affected their mechanical behaviour. CLINICAL RELEVANCE: PTG showed the highest NCF, suitable for markedly curved canals. ETP had the highest torsional resistance, appropriate for narrow and constricted canals.
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5-(3'-Indolyl)oxazole moiety is a privileged heterocyclic scaffold, embedded in many biologically interesting natural products and potential therapeutic agents. Compounds containing this scaffold, whether from natural sources or synthesized, have demonstrated a wide array of biological activities. This has piqued the interest of synthetic chemists, leading to a large number of reported synthetic approaches to 5-(3'-indolyl)oxazole scaffold in recent years. In this review, we comprehensively overviewed the different biological activities and chemical synthetic methods for the 5-(3'-indolyl)oxazole scaffold reported in the literatures from 1963 to 2024. The focus of this study is to highlight the significance of 5-(3'-indolyl)oxazole derivatives as the lead compounds for the lead discovery of anticancer, pesticidal, antimicrobial, antiviral, antioxidant and anti-inflammatory agents, to summarize the synthetic methods for the 5-(3'-indolyl)oxazole scaffold. In addition, the reported mechanism of action of 5-(3'-indolyl)oxazoles and advanced molecules studied in animal models are also reviewed. Furthermore, this review offers perspectives on how 5-(3'-indolyl)oxazole scaffold as a privileged structure might be exploited in the future.
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Breast cancer is a heterogeneous disease that arises as a multi-stage process involving multiple cell types. Patients diagnosed with the same clinical stage and pathological classification may have different prognoses and therapeutic responses due to alterations in molecular genetics. As an essential marker for the molecular subtyping of breast cancer, long non-coding RNAs (lncRNAs) play a crucial role in gene expression regulation, cell differentiation, and the maintenance of genomic stability. Here, we developed a modular framework for lncRNA identification and applied it to a breast cancer cohort to identify novel lncRNAs not previously annotated. To investigate the potential biological function, regulatory mechanisms, and clinical relevance of the novel lncRNAs, we elucidated the genomic and chromatin features of these lncRNAs, along with the associated protein-coding genes and putative enhancers involved in the breast cancer regulatory networks. Furthermore, we uncovered that the expression patterns of novel and annotated lncRNAs identified in breast cancer were related to the hormone response in the PAM50 subtyping criterion, as well as the immune response and progression states of breast cancer across different immune cells and immune checkpoint genes. Collectively, the comprehensive identification and functional analysis of lncRNAs revealed that these lncRNAs play an essential role in breast cancer by altering gene expression and participating in the regulatory networks, contributing to a better insight into breast cancer heterogeneity and potential avenues for therapeutic intervention.
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Breast Neoplasms , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , RNA, Long Noncoding , Humans , RNA, Long Noncoding/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Female , Transcriptome , Biomarkers, Tumor/genetics , PrognosisABSTRACT
OBJECTIVE: To elucidate the clinicopathological characteristics and oncological outcomes of a special group of patients with gestational trophoblastic neoplasia (GTN) initially presenting with isolated lung lesions, elevated human chorionic gonadotropin (hCG) levels, and unobserved pelvic lesions. METHODS: Overall, 2358 patients with GTN treated at our hospital between 2000 and 2023 were retrospectively reviewed, and 40 patients were evaluated. The demographic characteristics, clinicopathological features, treatment data, and follow-up information of each patient were collected. The primary outcome was progression free survival. Kaplan-Meier analysis and univariate and multivariate Cox proportional hazard analyses were used to identify the risk factors. RESULTS: Among the 40 patients, 95.0 % had solitary lung lesions, with a median size of 1.9 cm. Moreover, 72.5 % of patients were pathologically confirmed as epithelioid trophoblastic tumors (ETT). During a median follow-up period of 53.5 months (range, 2-143), 11 patients experienced recurrence, including all patients who received chemotherapy alone as the initial treatment, and no death was observed. Relapse treatment involved lung segmentectomy and lobectomy combined with chemotherapy and immunotherapy. Univariate and multivariate Cox analyses identified comparing with surgery±chemotherapy, chemotherapy alone as the initial treatment (hazard ratio [HR] =7.738, 95 % confidence interval [CI] 1.698-35.269, P = 0.008) as independent risk factor for recurrence. CONCLUSIONS: In patients with a history of pregnancy exhibiting isolated pulmonary lesions, elevated hCG levels (mostly <1000 mIU/mL), and unobserved pelvic lesions, ETT should be considered first. Surgical resection of lung lesion is crucial for optimal management. When chemotherapy is considered, multidrug regimen is recommended.
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Lithium, a representative alkali metal, holds the coveted status of the "holy grail" in the realm of next-generation rechargeable batteries, owing to its remarkable theoretical specific capacity and low electrode potential. However, the inherent reactivity of Li metal inevitably results in the formation of the solid-electrolyte interphase (SEI) on its surface, adding complexity to the Li electrodeposition process compared to conventional metal electrodeposition. Attaining uniform Li deposition is crucial for ensuring stable, long-cycle performance and high Coulombic efficiency in Li metal batteries, which requires a comprehensive understanding of the underlying factors governing the electrodeposition process. This review delves into the intricate kinetics of Li electrodeposition, elucidating the multifaceted factors that influence charge and mass transfer kinetics. The intrinsic relationship between charge transfer kinetics and Li deposition is scrutinized, exploring how parameters such as current density and electrode potential impact Li nucleation and growth, as well as dendrite formation. Additionally, the applicability of classical mass-transfer-controlled electrodeposition models to Li anode systems is evaluated, considering the influence of ionic concentration and solvation structure on Li+ transport, SEI formation, and subsequent deposition kinetics. The pivotal role of SEI compositional structure and physicochemical properties in governing charge and mass transfer processes is underscored, with an emphasis on strategies for regulating Li deposition kinetics from both electrolyte and SEI perspectives. Finally, future directions in Li electrodeposition research are outlined, emphasizing the importance of ongoing exploration from a kinetic standpoint to fully unlock the potential of Li metal batteries.
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Despite the recent proliferation of scholarly investigations on servant leadership, clarity remains elusive regarding the specific mechanisms and conditions underpinning employee cognitive processes and their responses to servant leadership. Drawing upon social cognitive theory, proposes a moderated mediation model tested through a time-lagged field data from 489 employees in Study 1 and an experimental data in Study 2. We found that servant leadership indirectly enhances employee voice behavior through increased employee work reflection. Additionally, we considered employee proactive personality as a boundary condition for the positive effect of servant leadership. Our results show that servant leadership prompts employee work reflection only when the level of employee proactive personality is high, which in turn increases employee voice behavior. This study presents significant theoretical and practical implications through the integration of social cognitive theory with servant leadership research.
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We report a novel and efficient method for the preparation of diarylmethyl sulfonamide derivatives through visible-light-induced sulfamoylation of para-quinone methides with sulfamoyl chlorides under mild, metal-free conditions. This protocol demonstrates excellent tolerance toward a wide range of functional groups, affording the corresponding products in moderate to high yields. Preliminary mechanism studies revealed that the excited photocatalyst rhodamine 6G* was mainly quenched by para-quinone methides and the generated diarylmethyl radical intermediates then underwent radical-radical cross-coupling with sulfamoyl radicals to yield the diarylmethyl sulfonamides.
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BACKGROUND AND PURPOSE: Toll-like receptors (TLRs) are involved in innate immunity and inflammatory responses in various diseases. Our study aimed to investigate the association between the levels of soluble TLR4 (sTLR4) and soluble TLR2 (sTLR2) and clinical outcomes following intracerebral hemorrhage (ICH). METHODS: Patients admitted to department of Neurology with acute ICH were included. Plasma levels of sTLR4 and sTLR2 after ICH were measured by enzyme-linked immunosorbent assay. Poor clinical outcome was defined as a modified Rankin score (mRS) of 3-6 at 3-month and 12-month after onset. RESULTS: All 207 patients with ICH and 100 non-stroke controls were included in our analysis. The mean sTLR4 level was 4.53±1.51â¯ng/ml and mean sTLR2 level was 3.65±0.72â¯ng/ml. There was significant trend towards worse clinical outcomes with increasing sTLR4 and sTLR2 terciles at 3 and 12 months. According to receiver operating curve (ROC), the sTLR4 was reliable predictor for poor clinical outcome at 3 months (ROC=0.75) and 12 months (ROC=0.74). The sTLR2 was less reliable predictor for poor clinical outcome at 3 months (ROC=0.64) and 12 months (ROC=0.65). The level of sTLR4 was an independent predictor of poor clinical outcome at 12-month (OR 1.24, 95â¯% CI 1.16-1.80; P=0.019). CONCLUSIONS: The sTLR4 quantification may provide accurate prognostic information after ICH.
Subject(s)
Cerebral Hemorrhage , Toll-Like Receptor 2 , Toll-Like Receptor 4 , Humans , Toll-Like Receptor 2/blood , Cerebral Hemorrhage/blood , Male , Female , Aged , Toll-Like Receptor 4/blood , Middle Aged , Treatment Outcome , Aged, 80 and over , Prognosis , Biomarkers/bloodABSTRACT
BACKGROUND: Liver cancer stem cells (CSCs) contribute to tumor initiation, progression, and recurrence in hepatocellular carcinoma (HCC). The Wnt/ß-catenin pathway plays a crucial role in liver cancer stemness, progression, metastasis, and drug resistance, but no clinically approved drugs have targeted this pathway efficiently so far. We aimed to elucidate the role of COLEC10 in HCC stemness. METHODS: The Cancer Genome Atlas (TCGA) and the Clinical Proteomic Tumor Analysis Consortium (CPTAC) databases were employed to search for the association between COLEC10 expression and HCC stemness. Colony formation, sphere formation, side population, and limiting dilution tumor initiation assays were used to identify the regulatory role of COLEC10 overexpression in the stemness of HCC cell lines. Wnt/ß-catenin reporter assay and immunoprecipitation were performed to explore the underlying mechanism. RESULTS: COLEC10 level was negatively correlated with HCC stemness. Elevated COLEC10 led to decreased expressions of EpCAM and AFP (alpha-fetoprotein), two common markers of liver CSCs. Overexpression of COLEC10 inhibited HCC cells from forming colonies and spheres, and reduced the side population numbers in vitro, as well as the tumorigenic capacity in vivo. Mechanically, we demonstrated that overexpression of COLEC10 suppressed the activity of Wnt/ß-catenin signaling by upregulating Wnt inhibitory factor WIF1 and reducing the level of cytoplasmic ß-catenin. COLEC10 overexpression promoted the interaction of ß-catenin with the component of destruction complex CK1α. In addition, KLHL22 (Kelch Like Family Member 22), a reported E3 ligase adaptor predicted to interact with CK1α, could facilitate COLEC10 monoubiquitination and degradation. CONCLUSION: COLEC10 inhibits HCC stemness by downregulating the Wnt/ß-catenin pathway, which is a promising target for liver CSC therapy.
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The concept of reference sample was put forward in the Guidance on CMC of Traditional Chinese Medicine Compound Preparations Developed from Catalogued Ancient Classical Prescriptions(Interim). The research on reference sample is a key link in the research and development of traditional Chinese medicine(TCM) compound prescriptions from catalogued ancient classical prescriptions(known as Category 3.1 TCM). This paper discusses the content of research on reference sample by analyzing the characteristics of Category 3.1 TCM and the purpose of research on reference sample. Furthermore, suggestions on the research of reference sample are proposed according to the development and evaluation practice of Category 3.1 TCM and research achievements of TCM regulatory science, aiming to provide reference for colleagues in this industry.
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Drugs, Chinese Herbal , Medicine, Chinese Traditional , Drugs, Chinese Herbal/chemistry , Humans , Drug Prescriptions , History, Ancient , ChinaABSTRACT
Graphene has been extensively utilized as an electrode material for nonaqueous electrochemical capacitors. However, a comprehensive understanding of the charging mechanism and ion arrangement at the graphene/electrolyte interface remain elusive. Herein, a gap-enhanced Raman spectroscopic strategy is designed to characterize the dynamic interfacial process of graphene with an adjustable number of layers, which is based on synergistic enhancement of localized surface plasmons from shell-isolated nanoparticles and a metal substrate. By employing such a strategy combined with complementary characterization techniques, we study the potential-dependent configuration of adsorbed ions and capacitance curves for graphene based on the number of layers. As the number of layers increases, the properties of graphene transform from a metalloid nature to graphite-like behavior. The charging mechanism shifts from co-ion desorption in single-layer graphene to ion exchange domination in few-layer graphene. The increase in area specific capacitance from 64 to 145 µF cm-2 is attributed to the influence on ion packing, thereby impacting the electrochemical performance. Furthermore, the potential-dependent coordination structure of lithium bis(fluorosulfonyl) imide in tetraglyme ([Li(G4)][FSI]) at graphene/electrolyte interface is revealed. This work adds to the understanding of graphene interfaces with distinct properties, offering insights for optimization of electrochemical capacitors.
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BACKGROUND: We previously reported that the HMGB1/TLR4 axis promoted inflammation during the acute phase of intracerebral hemorrhage. Given that this phase is known to involve neuronal pyroptosis and neuroinflammation, here we explore whether HMGB1/TLR signaling activate inflammasome and pyroptosis after intracerebral hemorrhage. METHODS: Autologous blood was injected into Sprague-Dawley rats to induce intracerebral hemorrhage. Neurological deficits were assessed using a modified neurological severity score. These expression and localization of NLRP1 and NLRP3 inflammasomes, as well as the levels of pyroptosis and pyroptosis-associated proteins were assessed using Western blot or immunocytochemistry. These experiments were repeated in animals that received treatment with short interfering RNAs against NLRP1 or NLRP3, with HMGB1 inhibitor ethyl pyruvate or TLR4 inhibitor TAK-242. RESULTS: Intracerebral hemorrhage upregulated NLRP1 and NLRP3 in the ipsilateral striatum and increased the proportions of these cells that were pyroptosis-positive. Additionally, the levels of caspase protein family (e.g., pro-caspase-1 and caspase-1), apoptosis-associated speck-like protein (ASC), pro-interleukin-1ß (IL-1ß), and IL-1ß were also elevated. These effects on pyroptosis and associated neurological deficit, were partially reversed by knockdown of NLRP1 or NLRP3, or by inhibition of HMGB1 or TLR4. Inhibition of HMGB1 or TLR4 resulted in the downregulation NLRP3 but not NLRP1. CONCLUSIONS: The HMGB1/TLR4 signaling may activate the NLRP3 inflammasome during the acute phase of intracerebral hemorrhage, resulting in the inflammatory process known as pyroptosis. These insights suggest potential therapeutic targets for the mitigation tissue injury and associated neurological deficits following hemorrhagic stroke.
Subject(s)
Cerebral Hemorrhage , HMGB1 Protein , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Pyroptosis , Rats, Sprague-Dawley , Toll-Like Receptor 4 , Animals , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Pyroptosis/physiology , Pyroptosis/drug effects , HMGB1 Protein/metabolism , Rats , Toll-Like Receptor 4/metabolism , Male , Cerebral Hemorrhage/metabolism , Inflammasomes/metabolism , Signal Transduction/physiology , Signal Transduction/drug effects , Nerve Tissue ProteinsABSTRACT
Tumour immunotherapy is an effective and essential treatment for cancer. However, the heterogeneity of tumours and the complex and changeable tumour immune microenvironment (TME) creates many uncertainties in the clinical application of immunotherapy, such as different responses to tumour immunotherapy and significant differences in individual efficacy. It makes anti-tumour immunotherapy face many challenges. Immunometabolism is a critical determinant of immune cell response to specific immune effector molecules, significantly affecting the effects of tumour immunotherapy. It is attributed mainly to the fact that metabolites can regulate the function of immune cells and immune-related molecules through the protein post-translational modifications (PTMs) pathway. This study systematically summarizes a variety of novel protein PTMs including acetylation, propionylation, butyrylation, succinylation, crotonylation, malonylation, glutarylation, 2-hydroxyisobutyrylation, ß-hydroxybutyrylation, benzoylation, lactylation and isonicotinylation in the field of tumour immune regulation and immunotherapy. In particular, we elaborate on how different PTMs in the TME can affect the function of immune cells and lead to immune evasion in cancer. Lastly, we highlight the potential treatment with the combined application of target-inhibited protein modification and immune checkpoint inhibitors (ICIs) for improved immunotherapeutic outcomes.
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Prosthetic hands have significant potential to restore the manipulative capabilities and self-confidence of amputees and enhance their quality of life. However, incompatibility between prosthetic devices and residual limbs can lead to secondary injuries such as skin pressure ulcers and restricted joint motion, contributing to a high prosthesis abandonment rate. To address these challenges, this study introduces a data-driven design framework (D3Frame) utilizing a multi-index optimization method. By incorporating motion/ pressure data, as well as clinical criteria such as pain threshold/ tolerance, from various anatomical sites on the residual limbs of amputees, this framework aims to optimize the structural design of the prosthetic socket, including the Antecubital Channel (AC), Lateral Epicondylar Region Contour (LC), Medial Epicondylar Region Contour (MC), Olecranon Region Contour (OC), Lateral Flexor/ Extensor Region (LR), and Medial Flexor/ Extensor Region (MR). Experiments on five forearm amputees verified the improved adaptability of the optimized socket compared to traditional sockets under three load conditions. The experimental results revealed a modest score enhancement on standard clinical scales and reduced muscle fatigue levels. Specifically, the percent effort of muscles and slope value of mean/ median frequency decreased by 19%, 70%, and 99% on average, respectively, and the average values of mean/ median frequency in the motion cycle both increased by approximately 5%. The proposed D3Frame in this study was applied to optimize the structural aspects of designated regions of the prosthetic socket, offering the potential to aid prosthetists in prosthesis design and, consequently, augmenting the adaptability of prosthetic devices.
Subject(s)
Amputees , Artificial Limbs , Hand , Prosthesis Design , Humans , Amputees/rehabilitation , Male , Adult , Algorithms , Middle Aged , Amputation Stumps/physiopathology , FemaleABSTRACT
Atomically ordered intermetallic compounds (IMCs) have been extensively studied for exploring catalysts with high activity, selectivity, and longevity. Compared to random alloys, IMCs present a more pronounced geometric and electronic effect with desirable catalytic performance. Their well-defined structure makes IMCs ideal model catalysts for studying the catalytic mechanism. This review focuses especially on elemental composition, electron transfer, and structure/phase evolution under high temperature treatment conditions, providing direct evidence for the migration and rearrangement of metal atoms through electron microscopy. We then present the outstanding applications of IMCs in growing single-walled nanotubes, hydrogenation/dehydrogenation reactions, and electrocatalysis from the perspective of electronic, geometric, strain, and bifunctional effects of ordered IMCs. Finally, the current obstacles associated with the use of in situ techniques are proposed, as well as future research possibilities.
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Rift Valley fever virus (RVFV) is a mosquito-borne pathogen that represents a significant threat to both human and veterinary public health. Since its discovery in the Great Rift Valley of Kenya in the 1930s, the virus has spread across Africa and beyond, now posing a risk of introduction into Southern Europe and Asia. Despite recent progresses, early RVFV-host cell interactions remain largely uncharacterized. In this method chapter, we delineate the procedure for labeling RVFV particles with fluorescent organic dyes. This approach makes it feasible to visualize single viral particles in both fixed and living cells and study RVFV entry into host cells. We provide additional examples with two viruses closely related to RVFV, namely, Toscana virus and Uukuniemi virus. Furthermore, we illustrate how to utilize fluorescent viral particles to examine and quantify each step of the cell entry program of RVFV, which includes state-of-the-art fluorescence-based detection techniques such as fluorescence microscopy, flow cytometry, and fluorimetry.
Subject(s)
Fluorescent Dyes , Microscopy, Fluorescence , Rift Valley fever virus , Virion , Rift Valley fever virus/isolation & purification , Humans , Virion/isolation & purification , Animals , Fluorescent Dyes/chemistry , Microscopy, Fluorescence/methods , Flow Cytometry/methods , Virus Internalization , Rift Valley Fever/virology , Rift Valley Fever/diagnosis , Staining and Labeling/methods , Cell LineABSTRACT
Alternating copolymers are crucial for diverse applications. While dispersity (Æ, also known as molecular weight distribution, MWD) influences the properties of polymers, achieving low dispersities in alternating copolymers poses a notable challenge via free radical polymerizations (FRPs). In this work, we demonstrated an unexpected discovery that dispersities are affected by the participation of charge transfer complexes (CTCs) formed between monomer pairs during free radical alternating copolymerization, which have inspired the successful synthesis of various alternating copolymers with low dispersities (>30 examples, Æ = 1.13-1.39) under visible-light irradiation. The synthetic method is compatible with binary, ternary and quaternary alternating copolymerizations and is expandable for both fluorinated and non-fluorinated monomer pairs. DFT calculations combined with model experiments indicated that CTC-absent reaction exhibits higher propagation rates and affords fewer radical terminations, which could contribute to low dispersities. Based on the integration of Monte Carlo simulation and Bayesian optimization, we established the relationship map between FRP parameter space and dispersity, further suggested the correlation between low dispersities and higher propagation rates. Our research sheds light on dispersity control via FRPs and creates a novel platform to investigate polymer dispersity through machine learning.
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Within pharmaceutical research, ensuring the enantiomeric purity of chiral compounds is critical. Specifically, chiral amines are a crucial category of compounds, due to their extensive therapeutic uses. However, the enantiomeric analysis of these compounds, particularly those with significant steric hindrance, remains a challenge. To address this issue, our research introduces a novel chiral 19F-tagged NNO palladium pincer probe, strategically engineered with an open binding site to accommodate bulky amines. This probe facilitates the enantiodifferentiation of such amines, as evidenced by the distinct 19F NMR signals generated by the enantiomers. Moreover, our findings highlight the probe's applicability in the chiral discrimination of various psychoactive substances, underscoring its potential for the identification of illegal stimulant use and contributing to forensic investigations.