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Activation of the Wnt-ß-catenin signaling pathway by CHIR99021, a specific inhibitor of GSK3ß, induces Tcf7l1 protein degradation, which facilitates the maintenance of an undifferentiated state in mouse embryonic stem cells (mESCs); however, the precise mechanism is still unclear. Here, we showed that the overexpression of transducin-ß-like protein 1 (Tbl1, also known as Tbl1x) or its family member Tblr1 (also known as Tbl1xr1) can decrease Tcf7l1 protein levels, whereas knockdown of each gene increases Tcf7l1 levels without affecting Tcf7l1 transcription. Interestingly, only Tbl1, and not Tblr1, interacts with Tcf7l1. Mechanistically, Tbl1 translocates from the cytoplasm into the nucleus in association with ß-catenin (CTNNB1) after the addition of CHIR99021 and functions as an adaptor to promote ubiquitylation of the Tcf7l1 protein. Functional assays further revealed that enforced expression of Tbl1 is capable of delaying mESC differentiation. In contrast, knockdown of Tbl1 attenuates the effect of CHIR99021 on Tcf7l1 protein stability and mESC self-renewal. Our results provide insight into the regulatory network of the Wnt-ß-catenin signaling pathway involved in promoting the maintenance of naïve pluripotency.
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Células-Tronco Embrionárias Murinas , Proteína 1 Semelhante ao Fator 7 de Transcrição , Via de Sinalização Wnt , beta Catenina , Animais , Humanos , Camundongos , beta Catenina/metabolismo , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Proteínas Contendo Repetições de beta-Transducina/genética , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Proteólise/efeitos dos fármacos , Piridinas/farmacologia , Pirimidinas/farmacologia , Proteína 1 Semelhante ao Fator 7 de Transcrição/metabolismo , Proteína 1 Semelhante ao Fator 7 de Transcrição/genética , UbiquitinaçãoRESUMO
Binding affinity prediction largely determines the discovery efficiency of lead compounds in drug discovery. Recently, machine learning (ML)-based approaches have attracted much attention in hopes of enhancing the predictive performance of traditional physics-based approaches. In this study, we evaluated the impact of structural dynamic information on the binding affinity prediction by comparing the models trained on different dimensional descriptors, using three targets (i.e. JAK1, TAF1-BD2 and DDR1) and their corresponding ligands as the examples. Here, 2D descriptors are traditional ECFP4 fingerprints, 3D descriptors are the energy terms of the Smina and NNscore scoring functions and 4D descriptors contain the structural dynamic information derived from the trajectories based on molecular dynamics (MD) simulations. We systematically investigate the MD-refined binding affinity prediction performance of three classical ML algorithms (i.e. RF, SVR and XGB) as well as two common virtual screening methods, namely Glide docking and MM/PBSA. The outcomes of the ML models built using various dimensional descriptors and their combinations reveal that the MD refinement with the optimized protocol can improve the predictive performance on the TAF1-BD2 target with considerable structural flexibility, but not for the less flexible JAK1 and DDR1 targets, when taking docking poses as the initial structure instead of the crystal structures. The results highlight the importance of the initial structures to the final performance of the model through conformational analysis on the three targets with different flexibility.
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Simulação de Dinâmica Molecular , Proteínas , Ligantes , Proteínas/química , Ligação Proteica , Aprendizado de Máquina , Simulação de Acoplamento MolecularRESUMO
Protein loops play a critical role in the dynamics of proteins and are essential for numerous biological functions, and various computational approaches to loop modeling have been proposed over the past decades. However, a comprehensive understanding of the strengths and weaknesses of each method is lacking. In this work, we constructed two high-quality datasets (i.e. the General dataset and the CASP dataset) and systematically evaluated the accuracy and efficiency of 13 commonly used loop modeling approaches from the perspective of loop lengths, protein classes and residue types. The results indicate that the knowledge-based method FREAD generally outperforms the other tested programs in most cases, but encountered challenges when predicting loops longer than 15 and 30 residues on the CASP and General datasets, respectively. The ab initio method Rosetta NGK demonstrated exceptional modeling accuracy for short loops with four to eight residues and achieved the highest success rate on the CASP dataset. The well-known AlphaFold2 and RoseTTAFold require more resources for better performance, but they exhibit promise for predicting loops longer than 16 and 30 residues in the CASP and General datasets. These observations can provide valuable insights for selecting suitable methods for specific loop modeling tasks and contribute to future advancements in the field.
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Proteínas , Conformação Proteica , Proteínas/químicaRESUMO
BACKGROUND: Doxorubicin is an effective chemotherapy drug for treating various types of cancer. However, lethal cardiotoxicity severely limits its clinical use. Recent evidence has indicated that aberrant activation of the cytosolic DNA-sensing cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)-STING (stimulator of interferon genes) pathway plays a critical role in cardiovascular destruction. Here, we investigate the involvement of this mechanism in doxorubicin-induced cardiotoxicity (DIC). METHODS: Mice were treated with low-dose doxorubicin to induce chronic DIC. The role of the cGAS-STING pathway in DIC was evaluated in cGAS-deficiency (cGAS-/-), Sting-deficiency (Sting-/-), and interferon regulatory factor 3 (Irf3)-deficiency (Irf3-/-) mice. Endothelial cell (EC)-specific conditional Sting deficiency (Stingflox/flox/Cdh5-CreERT) mice were used to assess the importance of this pathway in ECs during DIC. We also examined the direct effects of the cGAS-STING pathway on nicotinamide adenine dinucleotide (NAD) homeostasis in vitro and in vivo. RESULTS: In the chronic DIC model, we observed significant activation of the cGAS-STING pathway in cardiac ECs. Global cGAS, Sting, and Irf3 deficiency all markedly ameliorated DIC. EC-specific Sting deficiency significantly prevented DIC and endothelial dysfunction. Mechanistically, doxorubicin activated the cardiac EC cGAS-STING pathway and its target, IRF3, which directly induced CD38 expression. In cardiac ECs, the cGAS-STING pathway caused a reduction in NAD levels and subsequent mitochondrial dysfunction via the intracellular NAD glycohydrolase (NADase) activity of CD38. Furthermore, the cardiac EC cGAS-STING pathway also regulates NAD homeostasis and mitochondrial bioenergetics in cardiomyocytes through the ecto-NADase activity of CD38. We also demonstrated that pharmacological inhibition of TANK-binding kinase 1 or CD38 effectively ameliorated DIC without compromising the anticancer effects of doxorubicin. CONCLUSIONS: Our findings indicate a critical role of the cardiac EC cGAS-STING pathway in DIC. The cGAS-STING pathway may represent a novel therapeutic target for preventing DIC.
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Cardiotoxicidade , Transdução de Sinais , Camundongos , Animais , NAD/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Doxorrubicina/toxicidadeRESUMO
The effects of the obliteration of portal venules (OPV) in cirrhotic portal hypertension are poorly understood. To investigate its contribution to portal hypertension in biliary cirrhosis and its underlying mechanism, we evaluated OPV using two-dimensional (2D) histopathology in liver explants from patients with biliary atresia (BA, n = 63), primary biliary cholangitis (PBC, n = 18), and hepatitis B-related cirrhosis (Hep-B-cirrhosis, n = 35). Then, three-dimensional (3D) OPV was measured by X-ray phase-contrast CT in two parallel models in rats following bile duct ligation (BDL) or carbon tetrachloride (CCl4) administration, representing biliary cirrhosis and post-necrotic cirrhosis, respectively. The portal pressure was also measured in the two models. Finally, the effects of proliferative bile ducts on OPV were investigated. We found that OPV was significantly more frequent in patients with biliary cirrhosis, including BA (78.57 ± 16.45%) and PBC (60.00 ± 17.15%), than that in Hep-B-cirrhotic patients (29.43 ± 14.94%, p < 0.001). OPV occurred earlier, evidenced by the paired liver biopsy at a Kasai procedure (KP), and was irreversible even after a successful KP in the patients with BA. OPV was also significantly more frequent in the BDL models than in the CCl4 models, as shown by 2D and 3D quantitative analysis. Portal pressure was significantly higher in the BDL model than that in the CCl4 model. With the proliferation of bile ducts, portal venules were compressed and irreversibly occluded, contributing to the earlier and higher portal pressure in biliary cirrhosis. OPV, as a pre-sinusoidal component, plays a key role in the pathogenesis of portal hypertension in biliary cirrhosis. The proliferated bile ducts and ductules gradually take up the 'territory' originally attributed to portal venules and compress the portal venules, which may lead to OPV in biliary cirrhosis. © 2024 The Pathological Society of Great Britain and Ireland.
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Hipertensão Portal , Cirrose Hepática Biliar , Veia Porta , Hipertensão Portal/patologia , Hipertensão Portal/fisiopatologia , Animais , Cirrose Hepática Biliar/patologia , Cirrose Hepática Biliar/complicações , Cirrose Hepática Biliar/fisiopatologia , Masculino , Humanos , Feminino , Veia Porta/patologia , Vênulas/patologia , Ratos , Adulto , Pressão na Veia Porta , Pessoa de Meia-Idade , Modelos Animais de Doenças , Fígado/patologia , Fígado/irrigação sanguínea , Ratos Sprague-Dawley , Ductos Biliares/patologia , Adulto Jovem , AdolescenteRESUMO
Fiber-integrated micro/nanostructures play a crucial role in modern industry, mainly owing to their compact size, high sensitivity, and resistance to electromagnetic interference. However, the three-dimensional manufacturing of fiber-tip functional structures beyond organic polymers remains challenging. It is essential to construct fiber-integrated inorganic silica with designed functional nanostructures for microsystem applications. Here, we develop a strategy for the 3D nanolithography of fiber-integrated silica from hybrid organic-inorganic materials by ultrafast laser-induced multiphoton absorption. Without silica nanoparticles and polymer additives, the acrylate-functionalized precursors can be locally cross-linked through a nonlinear effect. Followed by annealing at low temperature, the as-printed micro/nanostructures are transformed to high-quality silica with sub-100 nm resolution. Silica microcantilever probes and microtoroid resonators are directly integrated onto the optical fiber, showing strong thermal stability and quality factors. This work provides a promising strategy for fabricating desired fiber-tip silica micro/nanostructures, which is helpful for the development of integrated functional device applications.
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In the heterostructure of two-dimensional (2D) materials, many novel physics phenomena are strongly dependent on the Moiré superlattice. How to achieve the continuous manipulation of the Moiré superlattice in the same sample is very important to study the evolution of various physical properties. Here, in minimally twisted monolayer-multilayer graphene, we found that bubble-induced strain has a huge impact on the Moiré superlattice. By employing the AFM tip to dynamically and continuously move the nanobubble, we realized the modulation of the Moiré superlattice, like the evolution of regular triangular domains into long strip domain structures with single or double domain walls. We also achieved controllable modulation of the Moiré superlattice by moving multiple nanobubbles and establishing the coupling of nanobubbles. Our work presents a flexible method for continuous and controllable manipulation of Moiré superlattices, which will be widely used to study novel physical properties in 2D heterostructures.
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MHY1485 is an mTOR activator that inhibits the autophagy process by inhibiting the fusion between autophagosomes and lysosomes. This study aimed to explore the role and mechanism of MHY1485 in hepatocellular carcinoma (HCC) and to provide an in-depth understanding of the mechanisms of autophagy regulation in relation to adriamycin (ADM) resistance, as well as the development of a molecularly targeted autophagy-modulating approach. Here, ADM was used to treat HepG2 cells and construct an ADM-resistant cell model. The HepG2/ADM cell line and HepG2 cells were treated with MHY1485 and ADM, respectively, and the proliferation and apoptosis of HCC cells were detected using CCK8, clone formation, flow cytometry, and 5-ethynyl-2'-deoxyuridine staining assays. Ki-67, mTOR phosphorylation, and LC3A expression were detected by IF staining; the expression or phosphorylation levels of autophagy-related proteins (i.e., GLUT1, PGI, PFK, END, and MTHFD2) and apoptosis-related proteins (caspase-3, caspase-8, and caspase-9) were detected by qPCR and western blotting. The number of autophagosomes was determined by monodansylcadaverine staining. Our results showed that MHY1485 can inhibit the proliferation and growth of liver cancer cells, and that MHY1485 combined with ADM can effectively inhibit the tolerance of HepG2/ADM cells to ADM and enhance the efficacy of ADM. The results of the detection of the autophagy-related protein LC3A also indicated that MHY1485 activates mTOR and can affect the phosphorylation level of ULK1, inhibit autophagy, and enhance the sensitivity of liver cancer cells to adriamycin. In summary, MHY1485 can enhance the sensitivity of adriamycin-resistant cells to adriamycin by activating mTOR and blocking the autophagy process in cells; therefore, mTOR may become a potential target for the treatment of liver cancer.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Morfolinas , Triazinas , Humanos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Doxorrubicina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Células Hep G2 , Apoptose , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Autofagia , Proliferação de Células , Linhagem Celular TumoralRESUMO
Two-photon fluorescence lifetime microscopy (TP-FLIM) is a powerful quantitative imaging technique that characterizes and analyzes the structure and function of biological samples through a combination of intensity and lifetime imaging. Because TP-FLIM is independent of the fluorescence signal intensity and the fluorophore concentration, it is widely used in high-throughput, high-content drug screening and clinical diagnostics. Second harmonic generation (SHG) imaging technology has the advantages of high spatial resolution and imaging depth inherent to nonlinear optical imaging. Second harmonics often appear in noncentrosymmetric structures. Collagen tissue in biological organisms is a good example of these structures, showing strong harmonic effects. Therefore, SHG has been widely used for imaging of specific tissue structure imaging. TP-FLIM technology is highly sensitive for quantitatively detecting changes in microenvironments. The objective of this study is to examine pathological pulmonary fibrosis slices using a combined approach of TP-FLIM and SHG technology. The fluorescence lifetime data of pulmonary collagen fibers are analyzed by using phasor plot analysis methods, and normal collagen fibers and fibrotic collagen fibers are distinguished by calculating the aspect ratio from the SHG images formed by the collagen fibers. Our study provides a new method for a deeper understanding of the pathological mechanisms and clinical diagnosis of pulmonary fibrosis and other collagen fiber-related disorders.
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To enhance our comprehension of the fundamental mechanisms driving tumor metabolism and metastasis, it is essential to dynamically monitor intratumoral lipid droplet (LD) and collagen processes in vivo. Traditional LD analysis in tumors predominantly relies on observations of in vitro cells or tissue slices, which unfortunately hinder real-time insights into the dynamic behavior of LDs during in vivo tumor progression. In this study, we developed a dual-modality imaging technique that combines coherent anti-Stokes Raman scattering (CARS) and second-harmonic generation (SHG) microscopy for in vivo monitoring of tumor LDs and collagen alterations, assisted by a murine breast cancer 4T1 cell-based dorsal skinfold window. Specifically, we accomplished real-time observations and quantitative analysis of the LD size, density, and collagen alignment within living tumors through CARS/SHG imaging. Additionally, our findings demonstrate that real-time LD monitoring provides a valuable means of assessing the efficacy of anticancer drugs in vivo. We evaluated the impact of adipose activators on lipid metabolism, oxidative stress, and tumor suppression by monitoring changes in LD size and density. Overall, this study highlights the potential of dual-modality CARS/SHG microscopy as a sensitive and flexible tool for antitumor therapeutic strategies.
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OBJECTIVE(S): The emergence of antibiotic resistance has led to suboptimal treatment outcomes for Mycoplasma pneumoniae pneumonia (MPP). Exploring naturally occurring drug components that are both effective against MPP and non-toxic may be a promising choice. This study aimed to investigate the therapeutic effect of andrographolide nanoparticles on pneumonia caused by Mycoplasma pneumoniae infection. METHODS: Andrographolide alginate-poloxamer nanoparticles (AND-ALG-POL/NPs) were obtained by wet medium grinding, and the characterization and in vitro release of the prepared andrographolide nanoparticles were examined by high performance liquid chromatography, particle size analyzer, zeta potential meter and transmission electron microscopy. The cytotoxicity and anti-inflammatory effects of AND-ALG-POL/NPs were evaluated in vitro by MP-infected lung epithelial cells BEAS-2B. Symptoms of pneumonia, total cell count, total protein content and inflammatory factor levels in BALF were assessed by MP-induced pneumonia in BALB/c mice treated with AND-ALG-POL/NPs, and histopathological studies were performed on lung tissues from experimental animals. RESULTS: The results showed that the prepared AND-ALG-POL/NPs were homogeneous spherical with a diameter of 180 ± 23 nm, a zeta potential of (-14.4 ± 2.1) mV, an average encapsulation rate of 87.74 ± 0.87 %, and an average drug loading of 13.17 ± 0.54 %. AND-ALG-POL/NPs were capable of slow release in vitro and showed significant inhibitory ability against MP (P < 0.001). However, AND-ALG-POL/NPs were not cytotoxic to normal cells and alleviated MP infection-induced apoptosis and elevated inflammatory factors. In the in vivo experiments, AND-ALG-POL/NPs alleviated the symptoms of pneumonia in MPP mice, reduced the abnormally elevated total cell count, total protein content and inflammatory factor levels in BALF, and alleviated lung tissue edema, inflammatory cell infiltration and apoptosis (P < 0.001). Meanwhile, the therapeutic effects of AND-ALG-POL/NPs on MPP were similar to those of azithromycin (AZM) and higher than those of andrographolide (AND) free monotherapy (P < 0.001). CONCLUSION: In summary, the prepared AND-ALG-POL/NPs can effectively inhibit MPP in vitro and in vivo, and the effect is similar to that of AZM. Therefore, AND- ALG - POL/NPs have the potential to replace AZM as a potential drug for the treatment of MPP.
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Diterpenos , Nanopartículas , Pneumonia por Mycoplasma , Camundongos , Animais , Pneumonia por Mycoplasma/tratamento farmacológico , Mycoplasma pneumoniae , Pulmão/metabolismo , Nanopartículas/química , AzitromicinaRESUMO
Two-dimensional (2D) materials with multiphase, multielement crystals such as transition metal chalcogenides (TMCs) (based on V, Cr, Mn, Fe, Cd, Pt and Pd) and transition metal phosphorous chalcogenides (TMPCs) offer a unique platform to explore novel physical phenomena. However, the synthesis of a single-phase/single-composition crystal of these 2D materials via chemical vapour deposition is still challenging. Here we unravel a competitive-chemical-reaction-based growth mechanism to manipulate the nucleation and growth rate. Based on the growth mechanism, 67 types of TMCs and TMPCs with a defined phase, controllable structure and tunable component can be realized. The ferromagnetism and superconductivity in FeXy can be tuned by the y value, such as superconductivity observed in FeX and ferromagnetism in FeS2 monolayers, demonstrating the high quality of as-grown 2D materials. This work paves the way for the multidisciplinary exploration of 2D TMPCs and TMCs with unique properties.
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This study explored the role of transient receptor potential channel melastatin 2 (TRPM2)-mediated activation of NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome in osteogenesis during healing of tooth extraction sockets. Tooth extraction socket tissue samples were collected from patients with or without periodontitis. In a TRPM2 knockout mouse model of socket healing, mice with or without periodontitis and their wild-type littermates were used for comparing the socket healing phenotypes. Micro-computed tomography imaging, three-dimensional reconstruction of the sockets, and hematoxylin and eosin staining for histopathologic analysis were performed. Immunofluorescence, immunohistochemistry, and Western blot analysis were used for evaluation of protein expression; the mRNA levels were evaluated by quantitative RT-PCR. Osteogenic, chondrogenic, and adipogenic differentiation potential of human bone marrow mesenchymal stem cells (BMMSCs) was evaluated. Calcium deposition was evaluated using Alizarin Red S staining. NLRP3 and CASP1 were up-regulated in tooth sockets of periodontitis patients. NLRP3 knockdown promoted the osteogenic differentiation of maxillary BMMSCs under inflammatory conditions. TRPM2 was up-regulated in the tooth extraction socket tissue of periodontitis. Inhibiting TRPM2 expression mitigated the NLRP3 inflammasome and its deleterious effect on osteogenesis. Activation of the TRPM2 ion channel regulated osteogenesis of BMMSCs under inflammatory conditions via Ca2+ influx, the mitochondrial dynamics, and pyroptosis. Targeting the TRPM2/Ca2+/NLRP3 axis could be beneficial in the healing process of the tooth extraction sockets of patients with periodontitis.
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Periodontite , Canais de Cátion TRPM , Canais de Potencial de Receptor Transitório , Humanos , Camundongos , Animais , Inflamassomos/metabolismo , Osteogênese/fisiologia , Alvéolo Dental/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo , Microtomografia por Raio-X , Camundongos Endogâmicos NOD , Extração DentáriaRESUMO
Sapphire fiber Bragg grating (SFBG) is a promising high-temperature strain sensor due to its melting point of 2045°C. However, the study on the long-term stability of SFBG under high temperature with an applied strain is still missing. In this paper, we reported for the first time to our knowledge on the critical temperature point of plastic deformation of the SFBG and demonstrated that the SFBG strain sensor can operate stably below 1200°C. At first, we experimentally investigated the topography and the spectral characteristics of the SFBG at different temperatures (i.e., 25°C, 1180°C, and 1600°C) with applied 650⠵ε. The reflection peak of the SFBG exhibits a redshift of about 15â nm and broadens gradually within 8â h at 1600°C, and the tensile force value decreases by 0.60â N in this process. After the test, the diameter of the SFBG region decreases from 100 to 88.6â µm, and the grating period is extended from 1.76 to 1.79â µm. This indicates that the plastic deformation of the SFBG happened indeed, and it was elongated irreversibly. Moreover, the stability of the Bragg wavelength of the SFBG under high temperature with the applied strain was evaluated. The result demonstrates the SFBG can be used to measure strain reliably below 1200°C. Furthermore, the strain experiments of SFBG at 25°C, 800°C, and 1100°C have been carried out. A linear fitting curve with high fitness (R2 > 0.99) and a lower strain measurement error (<15⠵ε) can be obtained. The aforementioned results make SFBG promising for high-temperature strain sensing in many fields, such as, power plants, gas turbines, and aerospace vehicles.
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This publisher's note contains a correction to Opt. Lett.48, 3219 (2023)10.1364/OL.486644.
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We demonstrate a novel, to the best of our knowledge, high-temperature pressure sensor based on a highly birefringent fiber Bragg grating (Hi-Bi FBG) fabricated in a dual side-hole fiber (DSHF). The Hi-Bi FBG is generated by a femtosecond laser directly written sawtooth structure in the DSHF cladding along the fiber core through the slow axis (i.e., the direction perpendicular to the dual-hole axis). The sawtooth structure serves as an in-fiber stressor and also generates Bragg resonance due to its periodicity. The DSHF was etched by hydrofluoric acid to increase its pressure sensitivity, and the diameter of two air holes was enlarged from 38.2 to 49.6â µm. A Hi-Bi FBG with a birefringence of up to 1.8 × 10-3 was successfully created in the etched DSHF. Two distinct reflection peaks could be observed by using a commercial FBG interrogator. Moreover, pressure measurement from 0 to 3â MPa at a high temperature of 700°C was conducted by monitoring the birefringence-induced peak splits and achieved a high-pressure sensitivity of -21.2â pm/MPa. The discrimination of the temperature and pressure could be realized by simultaneously measuring the Bragg wavelength shifts and peak splits. Furthermore, a wavelength-division-multiplexed (WDM) Hi-Bi FBG array was also constructed in the DSHF and was used for quasi-distributed high-pressure sensing up to 3â MPa. As such, the proposed femtosecond laser-inscribed Hi-Bi FBG is a promising tool for high-temperature pressure sensing in harsh environments, such as aerospace vehicles, nuclear reactors, and petrochemical industries.
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BACKGROUND AND AIMS: Sarcopenia is associated with poor prognosis, but its role in older patients with intrahepatic cholangiocarcinoma (ICC) is unclear. We aimed to evaluate the impact of sarcopenia on the prognosis of older patients with ICC undergoing hepatectomy. METHODS: A total of 363 patients with ICC following hepatectomy from 2015 to 2021 were retrospectively reviewed at five institutions. Sarcopenia was evaluated using skeletal muscle index by computed tomography images. Patients were divided into four subgroups according to sarcopenia and age. Postoperative outcomes including complication, overall survival (OS) and recurrence-free survival (RFS) were evaluated. Risk factors were identified through univariate and multivariate Cox regression analyses. RESULTS: 302 patients were included in the analysis. The median age was 63 years and there were 128 patients (42.4%) aged over 65 years. 192 patients (63.6%) were diagnosed with sarcopenia, while 180 patients (59.6%) experienced myosteatosis. Older patients experienced a higher incidence of sarcopenia and myosteatosis, and worse postoperative outcomes than younger patients. In the subgroup of patients with sarcopenia, older patients experienced a significant shorter OS than younger patients, which was not observed in patients without sarcopenia. According to the multivariate Cox regression analysis, lymphatic metastasis (p < .001), blood transfusion (p = .004), low serum albumin (p = .051), sarcopenia (p = .024), and myosteatosis (p = .004) were identified as independent risk factors of OS in older patients, meanwhile tumour size (p = .013) and lymphatic metastasis (p < .001) were independent risk factors of RFS. CONCLUSIONS: Sarcopenia and myosteatosis have a significant adverse impact on postoperative outcomes in older patients with ICC undergoing hepatectomy.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Sarcopenia , Humanos , Idoso , Pessoa de Meia-Idade , Hepatectomia/efeitos adversos , Sarcopenia/complicações , Sarcopenia/diagnóstico por imagem , Estudos Retrospectivos , Metástase Linfática/patologia , Colangiocarcinoma/patologia , Prognóstico , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologiaRESUMO
The introduction of AlphaFold2 (AF2) has sparked significant enthusiasm and generated extensive discussion within the scientific community, particularly among drug discovery researchers. Although previous studies have addressed the performance of AF2 structures in virtual screening (VS), a more comprehensive investigation is still necessary considering the paramount importance of structural accuracy in drug design. In this study, we evaluate the performance of AF2 structures in VS across three common drug discovery scenarios: targets with holo, apo, and AF2 structures; targets with only apo and AF2 structures; and targets exclusively with AF2 structures. We utilized both the traditional physics-based Glide and the deep-learning-based scoring function RTMscore to rank the compounds in the DUD-E, DEKOIS 2.0, and DECOY data sets. The results demonstrate that, overall, the performance of VS on AF2 structures is comparable to that on apo structures but notably inferior to that on holo structures across diverse scenarios. Moreover, when a target has solely AF2 structure, selecting the holo structure of the target from different subtypes within the same protein family produces comparable results with the AF2 structure for VS on the data set of the AF2 structures, and significantly better results than the AF2 structures on its own data set. This indicates that utilizing AF2 structures for docking-based VS may not yield most satisfactory outcomes, even when solely AF2 structures are available. Moreover, we rule out the possibility that the variations in VS performance between the binding pockets of AF2 and holo structures arise from the differences in their biological assembly composition.
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Descoberta de Drogas , Descoberta de Drogas/métodos , Proteínas/química , Proteínas/metabolismo , Conformação Proteica , Simulação de Acoplamento Molecular , Aprendizado Profundo , Humanos , Desenho de FármacosRESUMO
Given the escalating incidence of bacterial diseases and the challenge posed by pathogenic bacterial resistance, it is imperative to identify appropriate methodologies for conducting proteomic investigations on bacteria, and thereby promoting the target-based drug/pesticide discovery. Interestingly, a novel technology termed "activity-based protein profiling" (ABPP) has been developed to identify the target proteins of active molecules. However, few studies have summarized advancements in ABPP for identifying the target proteins in antibacterial-active compounds. In order to accelerate the discovery and development of new drug/agrochemical discovery, we provide a concise overview of ABPP and its recent applications in antibacterial agent discovery. Diversiform cases were cited to demonstrate the potential of ABPP for target identification though highlighting the design strategies and summarizing the reported target protein of antibacterial compounds. Overall, this review is an excellent reference for probe design towards antibacterial compounds, and offers a new perspective of ABPP in bactericide development.
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Bacterial infections and the consequent outburst of bactericide-resistance issues are fatal menace to both global health and agricultural produce. Hence, it is crucial to explore candidate bactericides with new mechanisms of action. The filamenting temperature-sensitive mutant Z (FtsZ) protein has been recognized as a new promising and effective target for new bactericide discovery. Hence, using a scaffold-hopping strategy, we designed new 7H-pyrrolo[2,3-d]pyrimidine derivatives, evaluated their antibacterial activities, and investigated their structure-activity relationships. Among them, compound B6 exhibited the optimal in vitro bioactivity (EC50 = 4.65 µg/mL) against Xanthomonas oryzae pv. oryzae (Xoo), which was superior to the references (bismerthiazol [BT], EC50 = 48.67 µg/mL; thiodiazole copper [TC], EC50 = 98.57 µg/mL]. Furthermore, the potency of compound B6 in targeting FtsZ was validated by GTPase activity assay, FtsZ self-assembly observation, fluorescence titration, Fourier-transform infrared spectroscopy (FT-IR) assay, molecular dynamics simulations, and morphological observation. The GTPase activity assay showed that the final IC50 value of compound B6 against XooFtsZ was 235.0 µM. Interestingly, the GTPase activity results indicated that the B6-XooFtsZ complex has an excellent binding constant (KA = 103.24 M-1). Overall, the antibacterial behavior suggests that B6 can interact with XooFtsZ and inhibit its GTPase activity, leading to bacterial cell elongation and even death. In addition, compound B6 showed acceptable anti-Xoo activity in vivo and low toxicity, and also demonstrated a favorable pharmacokinetic profile predicted by ADMET analysis. Our findings provide new chemotypes for the development of FtsZ inhibitors as well as insights into their underlying mechanisms of action.