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Axially chiral biaryls featuring a C-N axis are important functional molecules in diverse fields. The asymmetric Buchwald-Hartwig reaction represents a powerful strategy for these targets. Previous studies, however, have been predominantly restricted to intramolecular atroposelective coupling, likely due to the steric and entropic effects in the reductive elimination of Pd(II) species with sterically congested aryl and nitrogen groups. We now report two intermolecular Buchwald-Hartwig coupling systems of bulky NH lactams and halohydrocarbons enabled by rerouting the mechanism of C-N reductive elimination to one that accommodates sterically challenging substrates. Both atroposelective coupling systems exhibited functional group tolerance, excellent enantioselectivity, and high Z selectivity (if applicable), affording C-N atropisomeric biaryl and olefins through de novo construction of a C-N chiral axis. Experimental and computational studies were performed to elucidate the mechanism, and the switch of the reaction pathways is traced to the steric effect (ortho substituent) of the aryl halide substrate. A bulky 2,6-disubstituted aryl halide reorients the proximal lactamide ligand to its unusual O-ligation mode. With the amide oxygen participation, this intermediate undergoes C-N reductive elimination with an accessible barrier through a five-membered ring transition state, a pathway as well as a chiral induction mode that has been much underexplored in asymmetric catalysis.
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The construction of ecological networks within the context of urbanization is an effective approach to cope with the challenges of urban biodiversity decline, representing a crucial goal in urban planning and development. However, existing studies often overlook the richness and uniqueness within species communities by homogenizing traits of species in the same class. This study proposes a framework for constructing and optimizing ecological networks focused on differential conservation within the same class. By classifying birds into three groups (specialists of water, forest or urban areas) based on their ecological requirements and urbanization tolerance, we constructed an ecological network tailored to their distinct migratory dispersal patterns. We then identified strategic areas including pinch points, barriers, and breakpoints specific to each bird group. Our findings reveal notable variations in suitable habitat distribution among different bird groups in urban environments. Corridor layouts varied according to habitat preferences and migratory dispersal patterns. Despite these differences, urban built-up areas persist as central hubs for the distribution of suitable habitats for 75% of bird species, with peripheral mountain-plain transition areas constituting 63% of crucial dispersal corridors. This emphasizes the critical role of urban built-up areas in maintaining biodiversity and ecological connectivity. Prioritizing connectivity between central urban areas and distant natural spaces is imperative. Our approach innovatively classifies and constructs networks to identify strategic areas with diverse species-specific attributes, providing valuable spatial information for land planning and guiding solutions to enhance target species. While the primary focus is on bird conservation in Beijing, our framework is broadly applicable to global biodiversity management and green planning under urbanization challenges. Overall, this study offers innovative insights for urban planning development and serves as decision support for prioritizing urban actions.
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Gallium oxide (G a 2 O 3) photodetectors have drawn increased interest for their widespread applications ranging from military to civil. Due to the inherent oxygen vacancy defects, they seriously suffer from trade-offs that make them incompetent for high-responsivity, quick-response detection. Herein, a G a 2 O 3 nanocavity photodetector assisted with grating electrodes is designed to break the constraint. The proposed structure supports both the plasmonic mode and the Fabry-Perot (F-P) mode. Numerical calculations show that the absorption of 99.8% is realized for ultra-thin G a 2 O 3 (30 nm), corresponding to a responsivity of 12.35 A/W. Benefiting from optical mechanisms, the external quantum efficiency (EQE) reaches 6040%, which is 466 times higher than that of bare G a 2 O 3 film. Furthermore, the proposed photodetector achieves a polarization-dependent dichroism ratio of 9.1, enabling polarization photodetection. The grating electrodes also effectively reduce the transit time of the photo-generated carriers. Our work provides a sophisticated platform for developing high-performance G a 2 O 3 photodetectors with the advantages of simplified fabrication processes and multidimensional detection.
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Particulate matter (PM) pollution has posed a serious threat to public health, especially the global spread of infectious diseases. Most existing air filtration materials are still subjected to a compromise between removal efficiency and air permeability on account of their stacking bulk structures. Here, we proposed a self-polarized assembly technique to create two-dimensional piezoelectric nanofibrous webs (PNWs) directly from polymer solutions. The strategy involves droplets deforming into ultrathin liquid films by inertial flow, liquid films evolving into web-like architectures by instantaneous phase inversion, and enhanced dipole alignment by cluster electrostatics. The assembled continuous webs exhibit integrated structural superiorities of nanoscale diameters (â¼20 nm) of the internal fibers and through pores (â¼100 nm). Combined with the wind-driven electrostatic property derived from the enhanced piezoelectricity, the PNW filter shows high efficiency (99.48%) and low air resistance (34 Pa) against PM0.3 as well as high transparency (84%), superlight weight (0.7 g m-2), and long-term stable service life. This creation of such versatile nanomaterials may offer insight into the design and upgrading of high-performance filters.
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A stereodivergent synthesis of ß- and α-O-glycosides using 3-O-quinaldoyl glucals was developed by palladium catalysis at 60 and 110 °C respectively. Various alcohols, monosaccharides, and amino acid were glycosylated to form ß- and α- products in good yields with high stereoselectivity. Mechanistic studies indicated no classic Pd-N (quinoline) coordination, but π-π stacking interactions promoted the anomeric stereodiversity. The practicality was demonstrated by glycosylating natural products/drugs and synthesizing a complex tetrasaccharide.
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The gallium-doped hafnium oxide (Ga-HfO2) films with different Ga doping concentrations were prepared by adjusting the HfO2/Ga2O3 atomic layer deposition cycle ratio for high-speed and low-voltage operation in HfO2-based ferroelectric memory. The Ga-HfO2 ferroelectric films reveal a finely modulated coercive field (Ec) from 1.1 (HfO2/Ga2O3 = 32:1) to an exceptionally low 0.6 MV/cm (HfO2/Ga2O3 = 11:1). This modulation arises from the competition between domain nucleation and propagation speed during polarization switching, influenced by the intrinsic domain density and phase dispersion in the film with specific Ga doping concentrations. Higher Ec samples exhibit a nucleation-dominant switching mechanism, while lower Ec samples undergo a transition from a nucleation-dominant to a propagation-dominant reversal mechanism as the electric field increases. This work introduces Ga as a viable dopant for low Ec and offers insights into material design strategies for HfO2-based ferroelectric memory applications.
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BACKGROUND: Prospective observational studies have demonstrated that the machine learning (ML) -guided noninvasive chromosome screening (NICS) grading system, which we called the noninvasive chromosome screening-artificial intelligence (NICS-AI) grading system, can be used embryo selection. The current prospective interventional clinical study was conducted to investigate whether this NICS-AI grading system can be used as a powerful tool for embryo selection. METHODS: Patients who visited our centre between October 2018 and December 2021 were recruited. Grade A and B embryos with a high probability of euploidy were transferred in the NICS group. The patients in the control group selected the embryos according to the traditional morphological grading. Finally, 90 patients in the NICS group and 161 patients in the control group were compared statistically for their clinical outcomes. RESULTS: In the NICS group, the clinical pregnancy rate (70.0% vs. 54.0%, p < 0.001), the ongoing pregnancy rate (58.9% vs. 44.7%, p = 0.001), and the live birth rate (56.7% vs. 42.9%, p = 0.001) were significantly higher than those of the control group. When the female was ≥ 35 years old, the clinical pregnancy rate (67.7% vs. 32.1%, p < 0.001), ongoing pregnancy rate (56.5% vs. 25.0%, p = 0.001), and live birth rate (54.8% vs. 25.0%, p = 0.001) in the NICS group were significantly higher than those of the control group. Regardless of whether the patients had a previous record of early spontaneous abortion or not, the live birth rate of the NICS group was higher than that of the control group (61.0% vs. 46.9%; 57.9% vs. 34.8%; 33.3% vs. 0%) but the differences were not statistically significant. CONCLUSIONS: NICS-AI was able to improve embryo utilisation rate, and the live birth rate, especially for those ≥ 35 years old, with transfer of Grade A embryos being preferred, followed by Grade B embryos. NICS-AI can be used as an effective tool for embryo selection in the future.
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Aprendizado de Máquina , Taxa de Gravidez , Humanos , Feminino , Gravidez , Adulto , Estudos Prospectivos , Transferência de Embrião Único/métodos , Diagnóstico Pré-Implantação/métodos , Transferência Embrionária/métodos , Infertilidade Feminina/terapia , Infertilidade Feminina/genética , Infertilidade Feminina/diagnóstico , Resultado do Tratamento , Infertilidade/terapia , Infertilidade/diagnóstico , Infertilidade/genéticaRESUMO
BACKGROUND: The study was performed to investigate the efficacy and safety of preoperative dexamethasone (DXM) in preventing postoperative pulmonary complications (PPCs) after minimally invasive esophagectomy (MIE). METHODS: Patients who underwent total MIE with two-field lymph node dissection from February 2018 to February 2023 were included in this study. Patients who were given either 5 mg or 10 mg DXM as preoperative prophylactic medication before induction of general anesthesia were assigned to the DXM group, while patients who did not receive DXM were assigned to the control group. Preoperative evaluations, intraoperative data, and occurrence of postoperative complications were analyzed. The primary outcome was the incidence of PPCs occurring by day 7 after surgery. RESULTS: In total, 659 patients were included in the study; 453 patients received preoperative DXM, while 206 patients did not. Propensity score-matched analysis created a matched cohort of 366 patients, with 183 patients each in the DXM and control groups. A total of 24.6% of patients in the DXM group and 30.6% of patients in the control group had PPCs (P = 0.198). The incidence of respiratory failure was significantly lower in the DXM group than in the control group (1.1% vs 5.5%, P = 0.019). Fewer patients were re-intubated during their hospital stay in the DXM group than in the control group (1.1% vs 5.5%, P = 0.019). CONCLUSIONS: Preoperative DXM before induction of anesthesia did not reduce overall PPC development after MIE. Nevertheless, the occurrence of early respiratory failure and the incidence of re-intubation during hospitalization were decreased. TRIAL REGISTRATION: Chinese Clinical Trial Registry (No. ChiCTR2300071674; Date of registration, 22/05/2023).
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BACKGROUND AND PURPOSE: Hemorrhagic transformation remains a potentially devastating complication of acute ischemic stroke. We aimed to evaluate whether the hypoperfusion intensity ratio (HIR), a parameter derived from CT perfusion imaging, is associated with the development of hemorrhagic transformation in patients with anterior large-artery occlusion who had undergone thrombectomy. MATERIALS AND METHODS: We retrospectively reviewed data from consecutive acute ischemic stroke patients who had achieved successful recanalization (thrombolysis in cerebral infarction score ≥ 2b) between January 2020 and December 2023. HIR was defined as the ratio of the volume of lesions with a time-to-maximum (TMax) > 6 s to those with a Tmax > 10 s delay. The primary outcome, based on the European Cooperative Acute Stroke Study, was hemorrhagic transformation (HT), diagnosed by follow-up imaging assessment in 24 h windows, and radiologically classified as hemorrhagic infarction (HI) and parenchymal hematoma (PH). The secondary outcome was a 3-month mRS score of ≥3. RESULTS: Among 168 patients, 35/168 developed hemorrhagic transformation HT; 14/168 developed hemorrhagic infarction HI, and 21/168 developed parenchymal hematoma PH. After adjusting the latent covariates, increased hypoperfusion intensity ratio (per 0.1, adjusted OR [aOR] 1.68, 95% CI 1.26-2.25), ASPECTS (aOR 0.44, 95% CI 0.27-0.72), onset-to-puncture (aOR 1.01, 95% CI 1.00-1.02), and cardioembolism (aOR 5.6, 95% CI 1.59-19.7) were associated with hemorrhagic transformation in multivariable regression. The receiver operating characteristic curve indicated that HIR can predict HT accurately (area under the curve = 0.81; 95% CI, 0.738-0.882; P < 0.001) and predict PH (area under the curve = 0.801; 95% CI, 0.727-0.875; P < 0.001). CONCLUSIONS: Upon admission, hypoperfusion intensity ratio, an imaging parameter, predicted hemorrhagic transformation after reperfusion therapy in this patient population.ABBREVIATIONS: HT = hemorrhagic transformation; HIR = hypoperfusion intensity ratio; LVO = left vessel occlusion; EVT = endovascular thrombectomy; AIS = arterial ischemic stroke; OTP = onset-to-puncture; HI = hemorrhagic infarction; PH = parenchymal hematoma.
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Opioids are used for pain relief in patients suffering from acute myocardial ischemia or infarction. Clinical and laboratory studies demonstrate that morphine treated patients or the experimental animal model suffering acute myocardial ischemia and reperfusion, may worsen myocardial viability. As transient receptor potential vanilloid 1 (TRPV1) plays important roles in pain sensation and cardio-protection, we query whether opioids may exacerbate myocardial viability via interaction with TRPV1 activity in the pain relief. We found the co-expressions of TRPV1 and opioid µ, δ and κ receptors in adult rat cardiomyocytes. Intravenous injection of morphine (0.3 mg/kg) at 20 min after induction of myocardial ischemia, in the rat model of acute myocardial ischemia and reperfusion, induced significant reduction of phosphorylated TRPV1 (p-TRPV1) in the ventricular myocardium and increase in serum cardiac troponin I (cTnI), compared with the ischemia/reperfusion controls (all P < 0.05). The effects of morphine were completely reversed by selective opioid µ, δ and κ receptor antagonists. While significant upregulation of p-TRPV1 (P < 0.05) and improvement of ±dP/dt max (all P < 0.05) were detected in the animals giving the same dose of morphine before induction of myocardial ischemia. The changes in p-TRPV1 correlate with the alterations of cTnI (r = -0.5840, P = 0.0283) and ±dP/dt max (r = 0.8084, P = 0.0005 and r = -0.8133, P = 0.0004, respectively). The findings of this study may indicate that potentiation and attenuation of TRPV1 sensitivity correlate with the improvement of the cardiac performance and the aggravation of myocardial viability, respectively, by giving morphine before and during myocardial ischemia and reperfusion.
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Morfina , Traumatismo por Reperfusão Miocárdica , Ratos Sprague-Dawley , Canais de Cátion TRPV , Animais , Canais de Cátion TRPV/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Morfina/farmacologia , Fosforilação/efeitos dos fármacos , Masculino , Ratos , Fatores de Tempo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Analgésicos Opioides/farmacologia , Receptores Opioides/metabolismo , Troponina I/metabolismo , Troponina I/sangue , Miocárdio/metabolismo , Miocárdio/patologiaRESUMO
BACKGROUND: Low immune function after laparoscopic total gastrectomy puts patients at risk of infection-related complications. Low-dose naloxone (LDN) can improve the prognosis of patients suffering from chronic inflammatory diseases or autoimmune diseases. The use of LDN during perioperative procedures may reduce perioperative complications. The purpose of this study was to examine the effects of LDN on endogenous immune function in gastric cancer patients and its specific mechanisms through a randomized controlled trial. METHODS: Fifty-five patients who underwent laparoscopic-assisted total gastrectomy were randomly assigned to either a naloxone group (n = 23) or a nonnaloxone group (n = 22). Patients in the naloxone group received 0.05 µg/kg-1.h- 1naloxone from 3 days before surgery to 5 days after surgery via a patient-controlled intravenous injection (PCIA) pump, and patients in the nonnaloxone group did not receive special treatment. The primary outcomes were the rates of postoperative complications and immune function assessed by NK cell, CD3+ T cell, CD4+ T cell, CD8+ T cell, WBC count, neutrophil percentage, and IL-6 and calcitonin levels. The secondary outcomes were the expression levels of TLR4 (Toll-like receptor), IL-6 and TNF-α in gastric cancer tissue. RESULTS: Compared with the nonnaloxone group, the naloxone group exhibited a lower incidence of infection (in the incision, abdomen, and lungs) (P < 0.05). The numbers of NK cells and CD8+ T cells in the naloxone group were significantly greater than those in the nonnaloxone group at 24 h after surgery (P < 0.05) and at 96 h after surgery (P < 0.05). Compared with those in the nonnaloxone group, the CD3 + T-cell (P < 0.05) and CD4 + T-cell (P < 0.01) counts were significantly lower in the naloxone group 24 h after surgery. At 24 h and 96 h after surgery, the WBC count (P < 0.05) and neutrophil percentage (P < 0.05) were significantly greater in the nonnaloxone group. The levels of IL-6 (P < 0.05) and calcitonin in the nonnaloxone group were significantly greater at 24 h after surgery. At 24 h following surgery, the nonnaloxone group had significantly greater levels of IL-6 (P < 0.05) and calcitonin than did the naloxone group. Compared with those in the naloxone group, the expression levels of TLR4 (P < 0.05) in gastric cancer tissue in the naloxone group were greater; however, the expression levels of IL-6 (P < 0.01) and TNF-α (P < 0.01) in the naloxone group were greater than those in the nonnaloxone group. CONCLUSION: Laparoscopic total gastrectomy patients can benefit from 0.05 ug/kg- 1. h- 1 naloxone by reducing their risk of infection. It is possible that LDN alters the number of cells in lymphocyte subpopulations, such as NK cells, CD3 + T cells, and CD4 + T cells, and the CD4+/CD8 + T-cell ratio or alters TLR4 receptor expression in immune cells, thereby altering immune cell activity. TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry on 24/11/2023 (ChiCTR2300077948).
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Gastrectomia , Laparoscopia , Naloxona , Complicações Pós-Operatórias , Neoplasias Gástricas , Humanos , Naloxona/administração & dosagem , Gastrectomia/métodos , Masculino , Feminino , Laparoscopia/métodos , Pessoa de Meia-Idade , Neoplasias Gástricas/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Idoso , Antagonistas de Entorpecentes/administração & dosagem , Antagonistas de Entorpecentes/farmacologia , Assistência Perioperatória/métodos , Interleucina-6 , Receptor 4 Toll-LikeRESUMO
Laser lighting devices, comprising an ultraviolet (UV) laser chip and a phosphor material, have emerged as a highly efficient approach for generating high-brightness light sources. However, the high power density of laser excitation may exacerbate thermal quenching in conventional polycrystalline or amorphous phosphors, leading to luminous saturation and the eventual failure of the device. Here, for the first time, we raise a single-crystal (SCs) material for laser lighting considering the absence of grain boundaries that scatter electrons and phonons, achieving high thermal conductivity (0.81 W m-1 K-1) and heat-resistance (575 °C). The SCs products exhibit a high photoluminescence quantum yield (89%) as well as excellent stability toward high-power lasers (>12.41 kW/cm2), superior to all previously reported amorphous or polycrystalline matrices. Finally, the laser lighting device was fabricated by assembling the SC with a UV laser chip (50 mW), and the device can maintain its performance even after continuous operation for 4 h. Double perovskite single crystals doped with Yb3+/Er3+ demonstrated multimodal luminescence with the irradiation of 355 and 980 nm lasers, respectively. This characteristic holds significant promise for applications in spectrally tunable laser lighting and multimodal anticounterfeiting.
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Background: Two-lung ventilation (TLV) with artificial carbon dioxide (CO2) pneumothorax is used during the thoracoscopic phase of minimally invasive esophagectomy (MIE). However, the impact of TLV with artificial pneumothorax on postoperative pulmonary complications (PPCs) after MIE is unclear. This study aimed to compare the incidence of early PPCs between TLV with CO2 pneumothorax and one-lung ventilation (OLV) with bronchial blockade in patients undergoing MIE. Methods: Five hundred ninety-three patients with esophageal cancer who underwent elective MIE with two-field lymph node dissection were analyzed. Patients in the TLV group were intubated using a single-lumen endotracheal tube and underwent surgery using TLV with artificial CO2 pneumothorax. Patients in the OLV group underwent surgery using OLV with a bronchial blocker. Patient characteristics and intraoperative and PPC data were collected and analyzed. Propensity score matching (PSM) was performed to reduce confounding bias. Results: The TLV and OLV group comprised 513 and 80 patients, respectively. PSM matched 197 TLV group and 73 OLV group patients. Incidence of pneumonia within the first 3 days of surgery was higher in the TLV group (11.7% vs. 4.1%) but the difference was not significant (P=0.06). The incidence of infiltrates on chest radiography was 36.0% in the TLV group and 28.8% in the OLV group (P=0.26). Incidence of other major PPCs requiring treatment and major non-pulmonary postoperative complications did not significantly differ between the groups. Length of hospital stay was significantly longer in the TLV group (13.0 vs. 11.0 days; P=0.03). Conclusions: Compared with OLV with bronchial blockade, TLV with CO2 pneumothorax did not reduce the incidence of early PPCs after MIE.
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Monolayer molybdenum disulfide (M o S 2) has a weak light-matter interaction due to ultrathin thickness, which limits its potential application in lasing action. In this study, we propose a hybrid structure consisting of a nanocavity and Au nanoparticles to enhance the photon emission efficiency of monolayer M o S 2. Numerical simulations show that photoluminescence (PL) emission is significantly enhanced by introducing localized surface plasmon resonance (LSPR) to the proposed structure. Furthermore, an exciton energy band system is proposed to elucidate the physical mechanism of the PL process. By optimizing the spacer thickness, a high Purcell enhancement factor of 95 can be achieved. The results provided by this work pave the way to improve the PL efficiency of two-dimensional (2D) material, which constitutes a significant step towards the development of nanodevices such as nanolasers and sensors.
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Metallodrug-based photodynamic therapy (PDT) agents have demonstrated significant superiority against cancers, while their different chirality-induced biological activities remain largely unexplored. In this work, we successfully developed a pair of enantiopure mononuclear Ir(III)-based TLD-1433 analogues, Δ-Ir-3T and Λ-Ir-3T, and their enantiomer-dependent anticancer behaviors were investigated. Photophysical measurements revealed that they display high photostability and chemical stability, strong absorption at 400 nm with high molar extinction coefficients (ε = 5.03 × 104 M-1 cm-1), and good 1O2 relative quantum yields (ΦΔ ≈ 47%). Δ- and Λ-Ir-3T showed potent efficacy against MCF-7 cancer cells, with a photocytotoxicity index of ≤44â¯238. This impressive result, to the best of our knowledge, represents the highest value among reported mononuclear Ir(III)-based PDT agents. Remarkably, Λ-Ir-3T tended to be more potent than Δ-Ir-3T when tested against SK-MEL-28, HepG2, and LO2 cells, with consistent results across multiple test repetitions.
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Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Irídio , Fotoquimioterapia , Fármacos Fotossensibilizantes , Humanos , Irídio/química , Irídio/farmacologia , Estereoisomerismo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese químicaRESUMO
Nuclear condensates have been shown to regulate cell fate control, but its role in oncogenic transformation remains largely unknown. Here we show acquisition of oncogenic potential by nuclear condensate remodeling. The proto-oncogene SS18 and its oncogenic fusion SS18-SSX1 can both form condensates, but with drastically different properties and impact on 3D genome architecture. The oncogenic condensates, not wild type ones, readily exclude HDAC1 and 2 complexes, thus, allowing aberrant accumulation of H3K27ac on chromatin loci, leading to oncogenic expression of key target genes. These results provide the first case for condensate remodeling as a transforming event to generate oncogene and such condensates can be targeted for therapy. One sentence summary: Expulsion of HDACs complexes leads to oncogenic transformation.
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Histona Desacetilase 1 , Histona Desacetilase 2 , Proto-Oncogene Mas , Humanos , Histona Desacetilase 1/metabolismo , Histona Desacetilase 1/genética , Histona Desacetilase 2/metabolismo , Histona Desacetilase 2/genética , Núcleo Celular/metabolismo , Cromatina/metabolismo , Cromatina/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Histonas/metabolismo , AnimaisRESUMO
Ulcerative colitis (UC) is a chronic idiopathic inflammatory condition affecting the rectum and colon. Inflammation and compromisation of the intestinal mucosal barrier are key in UC pathogenesis. Resveratrol (Res) is a naturally occurring polyphenol that exhibits antiinflammatory and antioxidant properties. Nuclear factor erythroid2related factor 2/heme oxygenase 1 (Nrf2/HO1) pathway regulates occurrence and development of numerous types of diseases through antiinflammatory and antioxidant activity. However, it is not clear whether Nrf2/HO1 pathway is involved in the treatment of Res in UC. Therefore, the present study aimed to investigate whether Res modulates the Nrf2/HO1 signaling pathway to attenuate UC in mice. Dextran sulfate sodium (DSS) was used to induce experimental UC in male C57BL/6J mice. Disease activity index (DAI) and hematoxylin eosin (H&E) staning was used to assessed the magnitude of colonic lesions in UC mice. ELISA) was utilized to quantify inflammatory cytokines (IL6, IL1ß, TNFα and IL10) in serum and colon tissues. Immunohistochemistry and Western blot were used to evaluate the expression levels of tight junction (TJ) proteins [zonula occludens (ZO)1 and Occludin] in colon tissues. Pharmacokinetic (PK) parameters of Res were derived from TCMSP database. Networkpharmacology was employed to identify the biological function and pharmacological mechanism of Res in the process of relieving UC, and the key target was screened. The binding ability of Res and key target was verified by molecular docking. Finally, the effectiveness of key target was substantiated by Western blot. Res decreased DAI, ameliorated histopathological changes such as crypt loss, disappeatance of the mucosal epithelium, and inflammatory infiltration in mice. Additionally, Res decreased expression of proinflammatory cytokines IL6, IL1ß and TNFα and increased antiinflammatory factor IL10 expression. Res also restored the decreased protein expression of ZO1 and occludin after DSS treatment, increasing the integrity of the intestinal mucosal barrier. The PK properties of Res suggested that Res possesses the therapeutic potential for oral administration. Network pharmacology revealed that Res alleviated UC through antiinflammatory and antioxidant pathways, and confirmed that Nrf2 has a high binding affinity with Res and is a key target of Res against UC. Western blotting demonstrated that Res treatment increased the protein levels of Nrf2 and HO1. In conclusion, Res treatment activated the Nrf2/HO1 pathway to decrease clinical symptoms, inflammatory responses, and intestinal mucosal barrier damage in experimental UC mice.
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Experimentação Animal , Colite Ulcerativa , Colite , Masculino , Camundongos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Interleucina-10/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Colo/patologia , Antioxidantes/metabolismo , Interleucina-6/metabolismo , Ocludina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Farmacologia em Rede , Simulação de Acoplamento Molecular , Camundongos Endogâmicos C57BL , Citocinas/metabolismo , Anti-Inflamatórios/uso terapêutico , Sulfato de Dextrana , Modelos Animais de Doenças , Colite/patologiaRESUMO
Preclinical efficacy evaluation and tumor drug sensitivity analysis are two main applications of efficacy evaluation. Preclinical efficacy evaluation is to predict whether candidate drugs or therapies may improve patient outcomes in clinical trials. Tumor drug sensitivity analysis is an approach for the personalized evaluation and optimization of approved anti-cancer drugs and treatment regimens. Overall survival (OS) is the gold standard to evaluate the outcome of drugs or therapies in both clinical trials and clinical treatment. Many efficacy evaluation models, such as cell model, tumor cell-line transplant model, patient-derived tumor xenograft model, tumor organoid model, have been developed to assess the inhibitory effect of tested drugs or therapies on tumor growth. In fact, many treatments may also lead to malignant progression of tumors, such as chemotherapy, which can lead to metastasis. Therefore, tumor growth inhibition does not necessarily predict OS benefit. Whether it can prevent or inhibit tumor recurrence and metastasis is the key to whether drugs and therapies can improve patient outcomes. In this perspective, we summarize the current understanding of the pathological progression of tumor recurrence and metastasis, point out the shortcomings of existing tumor transplant models for simulating the clinical scenario of malignant progression of tumors, and propose five improved indicators for comprehensive efficacy evaluation to predict OS benefit using tumor orthotopic transplant and resection model. Improvement in the accuracy of efficacy evaluation will accelerate the development process of anti-cancer drugs or therapies, optimize treatment regimens to improve OS benefit, and reduce drug development and cancer treatment costs.
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Amphiphilic starches incorporating fatty acid ester chains of varying lengths and degrees of substitution (DS) were synthesized to fabricate starch-based micelles for oral delivery of hydrophobic bioactive molecules. The assembly of the amphiphilic starches is influenced by the concentration, temperature, and the chain length and DS of their fatty acid ester chain. Highly acidic environment can hydrolyze the amphiphilic starches, resulting in the formation of small-sized micelles. Conversely, high ionic concentration hinders the self-assembly of amphiphilic starches and the digestive fluids can dilute the amphiphilic starches concentration, leading to the micelle dissociation. However, amphiphilic starches with longer chain length and/or higher DS of the fatty acid ester chain possess greater hydrophobicity, enhancing the stability of starch-based micelles under varying conditions and favouring the protection of Trp-2 peptides during storage. The micelles demonstrate high cell bioaccessibility for Trp-2 peptides, with 59.25 % of Trp-2 peptides being transferred by the intestinal epithelium. These findings suggest a potential starch-based micelle system can be adjusted for the oral delivery of hydrophobic bioactive molecules.
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Micelas , Amido , Amido/química , Preparações de Ação Retardada , Portadores de Fármacos/química , Ésteres , Interações Hidrofóbicas e Hidrofílicas , Ácidos Graxos , PeptídeosRESUMO
Molybdenum sulfide (MoS2) as an emerging optoelectronic material, shows great potential for phototransistors owing to its atomic thickness, adjustable band gap, and low cost. However, the phototransistors based on MoS2have been shown to have some issues such as large gate leakage current, and interfacial scattering, resulting in suboptimal optoelectronic performance. Thus, Al-doped hafnium oxide (Hf1-xAlx) is proposed to be a dielectric layer of the MoS2-based phototransistor to solve this problem because of the relatively higher crystallization temperature and dielectric constant. Here, a high-performance MoS2phototransistor with Hf1-xAlxO gate dielectric layer grown by plasma-enhanced atomic layer deposition has been fabricated and studied. The results show that the phototransistor exhibits a high responsivity of 2.2 × 104A W-1, a large detectivity of 1.7 × 1017Jones, a great photo-to-dark current ratio of 2.2 × 106%, and a high external quantum efficiency of 4.4 × 106%. The energy band alignment and operating mechanism were further used to clarify the reason for the enhanced MoS2phototransistor. The suggested MoS2phototransistors could provide promising strategies in further optoelectronic applications.