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1.
Int J Biol Macromol ; 266(Pt 2): 131384, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38580012

RESUMO

One primary focus of skin tissue engineering has been the creation of innovative biomaterials to facilitate rapid wound healing. Extracellular matrix (ECM), an essential biofunctional substance, has recently been discovered to play a crucial role in wound healing. Consequently, we endeavored to decellularize ECM from pig achilles tendon and refine its mechanical and biological properties through modification by utilizing cross-linking agents. Glutaraldehyde (GA), 1-ethyl-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS), double aldol starch (DAS), and microbial transglutaminase (MTG) were utilized to produce crosslinked ECM variants (GA-ECM, EDC/NHS-ECM, DAS-ECM, and MTG-ECM). Comprehensive assessments were conducted to evaluate the physical properties, biocompatibility, and wound healing efficacy of each material. The results indicated that MTG-ECM exhibited superior tensile strength, excellent hydrophilicity, minimal cytotoxicity, and the best pro-healing impact among the four modified scaffolds. Staining analysis of tissue sections further revealed that MTG-ECM impeded the transition from type III collagen to type I collagen in the wound area, potentially reducing the development of wound scar. Therefore, MTG-ECM is expected to be a potential pro-skin repair scaffold material to prevent scar formation.

2.
Macromol Biosci ; : e2300549, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514930

RESUMO

The skin barrier is essential to prevent pathogenic invasion. When injury occurs, multiple biological pathways are promptly activated and wound repair processes are triggered. The effective healing of wounds is essential for survival, and dysfunction could result from aberrant wound repair. Preparation of many hydrogels, which involve the addition of growth/cell factors or mimic extracellular matrix (ECM) components, has not resulted in significant advances in tissue recovery. ECM contains a large number of biologically active molecules that activate a variety of cellular transduction pathways, which are essential for wound repair. Here, this work prepares hyaluronic acid-dopamine-thiourea (HA-DA-NCSN) hydrogels exhibiting ultrafast gelation in situ, following the methods of Xu et al., and subsequently designs a hydrogel containing ECM particles. In addition, the loaded ECM material, specifically decellularized ECM material, not only enhances the strength of the hydrogel network, but also delivers bioactive substances that make it a suitable platform for skin wound repair. The ECM hydrogel has great potential as an efficient bioactive wound dressing. This research suggests that this strategy is likely to improve skin wound closure in rat skin wound models.

3.
Int Immunopharmacol ; 130: 111519, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38442573

RESUMO

This study investigates the molecular mechanisms by which extracellular vesicles (EVs) derived from adipose-derived mesenchymal stem cells (ADSCs) promote M2 polarization of macrophages and thus reduce lung injury caused by sepsis. High-throughput sequencing was used to identify differentially expressed genes related to long non-coding RNA (lncRNA) in ADSC-derived EVs (ADSC-EVs) in sepsis lung tissue. Weighted gene co-expression network analysis (WGCNA) was employed to predict the downstream target genes of the lncRNA DLEU2. The RNAInter database predicted miRNAs that interact with DLEU2 and LXN. Functional and pathway enrichment analyses were performed using GO and KEGG analysis. A mouse model of sepsis was established, and treatment with a placebo or ADSC-EVs was administered, followed by RT-qPCR analysis. ADSC-EVs were isolated and identified. In vitro cell experiments were conducted using the mouse lung epithelial cell line MLE-12, mouse macrophage cell line RAW264.7, and mouse lung epithelial cell line (LEPC). ADSC-EVs were co-cultured with RAW264.7 and MLE-12/LEPC cells to study the regulatory mechanism of the lncRNA DLEU2. Cell viability, proliferation, and apoptosis of lung injury cells were assessed using CCK-8, EdU, and flow cytometry. ELISA was used to measure the levels of inflammatory cytokines in the sepsis mouse model, flow cytometry was performed to determine the number of M1 and M2 macrophages, lung tissue pathology was evaluated by H&E staining, and immunohistochemistry was conducted to examine the expression of proliferation- and apoptosis-related proteins. High-throughput sequencing and bioinformatics analysis revealed enrichment of the lncRNA DLEU2 in ADSC-EVs in sepsis lung tissue. Animal and in vitro cell experiments showed increased expression of the lncRNA DLEU2 in sepsis lung tissue after treatment with ADSC-EVs. Furthermore, ADSC-EVs were found to transfer the lncRNA DLEU2 to macrophages, promoting M2 polarization, reducing inflammation response in lung injury cells, and enhancing their viability, proliferation, and apoptosis inhibition. Further functional experiments indicated that lncRNA DLEU2 promotes M2 polarization of macrophages by regulating miR-106a-5p/LXN, thereby enhancing the viability and proliferation of lung injury cells and inhibiting apoptosis. Overexpression of miR-106a-5p could reverse the biological effects of ADSC-EVs-DLEU2 on MLE-12 and LEPC in vitro cell models. Lastly, in vivo animal experiments confirmed that ADSC-EVs-DLEU2 promotes high expression of LXN by inhibiting the expression of miR-106a-5p, further facilitating M2 macrophage polarization and reducing lung edema, thus alleviating sepsis-induced lung injury. lncRNA DLEU2 in ADSC-EVs may promote M2 polarization of macrophages and enhance the viability and proliferation of lung injury cells while inhibiting inflammation and apoptosis reactions, thus ameliorating sepsis-induced lung injury in a mechanism involving the regulation of the miR-106a-5p/LXN axis.


Assuntos
Lesão Pulmonar , MicroRNAs , Proteínas do Tecido Nervoso , RNA Longo não Codificante , Sepse , Animais , Camundongos , Apoptose/genética , Modelos Animais de Doenças , Lesão Pulmonar/microbiologia , Lesão Pulmonar/terapia , MicroRNAs/genética , RNA Longo não Codificante/administração & dosagem , RNA Longo não Codificante/genética , Sepse/complicações , Sepse/genética , Proteínas do Tecido Nervoso/genética , Células-Tronco Mesenquimais , Exossomos , Masculino , Camundongos Endogâmicos C57BL
4.
Transl Cancer Res ; 13(2): 1188-1195, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38482415

RESUMO

Background: CD5-positive (CD5+) non-germinal center B-cell-like diffuse large B-cell lymphoma (non-GCB DLBCL) is heterogeneous with a poor prognosis. For refractory DLBCL, the median overall survival was only 6.3 months. Therefore, there is a need for approaches to elongate the survival in this subgroup of relapsed DLBCL patients. Case Description: Here, we present a rare case of a 72-year-old patient with stage IV CD5+ non-GCB DLBCL with myeloid differentiation primary response 88 (MYD88) and cluster of differentiation 79B (CD79B) comutations. Zanubrutinib and rituximab therapy was initially administered until disease progression. Subsequently, zanubrutinib plus rituximab together with attenuated standard chemotherapy (miniCHOP) was applied and a notable response was observed. The patient tolerated the treatment well and exhibited a complete response in lung for about 5 months. Afterwards, the patients experienced relapse in the brain and started programmed death protein 1 (PD-1) regimens of toripalimab plus lenalidomide, which also exhibited a good response with decreased lesions in brain after half-year treatment. However, the patient experienced relapse again in the brain 3 months later and started chemotherapy with methotrexate plus rituximab. The patient had survived for over 2 years since the initial diagnosis of stage IV DLBCL and has continued to survive after experiencing a relapse in the brain for approximately 11 months till now. Conclusions: These findings suggest that toripalimab may be a new therapeutic option for central nervous system recurrence in refractory CD5+ DLBCL with MYD88 and CD79B comutation. Further clinical trials are warranted to confirm these results.

5.
Waste Manag ; 178: 76-84, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38382349

RESUMO

The efficient and sustainable recovery of rare earth resources from spent NdFeB magnets has received considerable and increasing attention. However, the currently prevalent NdFeB magnets recovery techniques focus only on the recovery for rare earth elements (REEs), some of which also recover cobalt (Co) or boron (B). Herein, a simple mechanochemical strategy was proposed to recover REE, Co, and B from spent NdFeB magnets by mixing the NdFeB magnets powder and FeCl3 6H2O through the grinding-roasting-water leaching technological route. The results indicated high leaching efficiencies of 98.94 % for REEs, 99.99 % for Co, and 93.36 % for B from the NdFeB magnets. Additionally, iron remains in the leaching residue as iron oxide (96.73 wt %), achieving the complete separation of REEs, Co, B, and Fe. This mechanochemical based technology offers a green and efficient recovery process, facilitating more effective synergistic recovery of valuable elements from spent NdFeB magnets.

6.
Cell Cycle ; 23(2): 169-187, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38267823

RESUMO

IL-33 has been associated with pro- and anticancer functions in cancer. However, its role in pancreatic cancer metastasis remains unknown. This study aimed to explore the role of miR-548t-5p/IL-33 axis in the metastasis of pancreatic cancer. Luciferase activity assay, qRT-PCR, Western blot and ELISA were performed to prove whether IL-33 is the target of miR-548t-5p. In vivo metastasis assay and cellular transwell assay were performed to explore the role of miR-548t-5p/IL-33 axis in the invasion and metastasis of pancreatic cancer. Co-culture experiments and immunohistochemistry were performed to observe whether IL-33 affects cell invasion and metastasis dependent on the involvement of M2 macrophages. THP-1 cell induction experiment and flow cytometry were performed to explore the effect of IL-33 on macrophage polarization. CCK-8, colony formation, cell apoptosis, cell cycle, cell wound healing and transwell assay were performed to investigate the effect of IL-33 induced M2 macrophages on cell malignant biological behavior by coculturing pancreatic cancer cells with the conditioned medium (CM) from macrophages. We found that miR-548t-5p regulated the expression and secretion of IL-33 in pancreatic cancer cells by directly targeting IL-33 mRNA. IL-33 secreted by cancer cells promoted the recruitment and activation of macrophages to a M2-like phenotype. In turn, IL-33 induced M2 macrophages promoted the migration and invasion of cancer cells. Moreover, IL-33 affected pancreatic cancer cell invasion dependent on the involvement of M2 macrophages in the co-culture system. Thus, our study suggested that manipulation of this IL-33-dependent crosstalk has a therapeutic potential for the treatment of pancreatic cancer metastasis.


Assuntos
Carcinoma Ductal Pancreático , Regulação Neoplásica da Expressão Gênica , Interleucina-33 , Macrófagos , MicroRNAs , Neoplasias Pancreáticas , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Interleucina-33/metabolismo , Interleucina-33/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Macrófagos/metabolismo , Animais , Linhagem Celular Tumoral , Metástase Neoplásica , Movimento Celular/genética , Invasividade Neoplásica , Camundongos , Apoptose/genética , Técnicas de Cocultura , Camundongos Nus , Proliferação de Células/genética , Células THP-1
7.
BMC Ophthalmol ; 24(1): 3, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166867

RESUMO

BACKGROUND: Multiple evanescent white dot syndrome (MEWDS)-like features is a rare condition triggered by a macular disease or iatrogenic injury, exhibiting MEWDS changes in the fundus. This study aims to describe the multimodal imaging features and outcomes of multifocal choroiditis/punctate inner choroidopathy (MFC/PIC) lesions with MEWDS-like features. METHODS: Six cases were studied retrospectively. All cases were given regional and oral corticosteroids. RESULTS: All cases showed an isolated juxtafoveal yellowish-white MFC/PIC lesion with disruption of RPE-Bruch's membrane-choriocapillaris complex (RPE-BM-CC), subretinal hyperreflective materials and choroidal thickening on optical coherence tomography. Two weeks after presentation, the grayish-white dots disappeared spontaneously and the corticosteroids were given. After four weeks, the ellipsoid zone (EZ) around the lesion and hyper-autofluorescence resolved. After 13 weeks, five cases showed shrinkage of the juxtafoveal lesion and restoration of foveal EZ. After six months, the juxtafoveal lesion became pigmented. Only one case developed type 2 choroidal neovascularization. CONCLUSIONS: The clinical course of MEWDS-like manifestations is still evanescent in our cases. The yellowish-white juxtafoveal MFC/PIC lesions with disruption of RPE-BM-CC and choroidal thickening showed a well-controlled prognosis after corticosteroid treatment.


Assuntos
Corioidite , Síndrome dos Pontos Brancos , Humanos , Coroidite Multifocal , Estudos Retrospectivos , Corioidite/diagnóstico , Corioidite/tratamento farmacológico , Síndrome dos Pontos Brancos/diagnóstico , Corticosteroides/uso terapêutico , Imagem Multimodal/métodos , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos
8.
iScience ; 27(1): 108737, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38269099

RESUMO

Lead (Pb(II)) contamination is common in liquid foods and can result from Pb(II) being present in the raw materials or during handling processes. However, due to the complexity of food matrices, there is limited data available concerning Pb(II) ion removal from food sources. This study focused on fabricating a PVA/PAA/DMTD electrospun nanofibrous membrane (ENFM) to efficiently and selectively remove Pb(II) ions from liquid foods. The PVA/PAA/DMTD ENFM had a maximum adsorption capacity of 138.3 mg/g for Pb(II) ions and demonstrated high selectivity toward the removal of Pb(II) ions. Negative values of the Gibbs free energy (ΔG°) showed that the spontaneous nature of the adsorption process was feasible at different temperatures. Moreover, it successfully removed Pb(II) ions from selected samples of commercially available drinks. Therefore, this adsorbent exhibits significant potential for removing Pb(II) ions from liquid food products, thereby reducing daily dietary exposure to Pb(II).

9.
J Am Chem Soc ; 146(2): 1410-1422, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38179949

RESUMO

Alkene radical ions constitute an integral and unique class of reactive intermediates for the synthesis of valuable compounds because they have both unpaired spins and charge. However, relatively few synthetic applications of alkene radical anions have emerged due to a dearth of generally applicable and mild radical anion generation approaches. Precise control over the chemo- and stereoselectivity in alkene radical anion-mediated processes represents another long-standing challenge due to their high reactivity. To overcome these issues, here, we develop a new redox-neutral strategy that seamlessly merges photoredox and copper catalysis to enable the controlled generation of alkene radical anions and their orthogonal enantioselective cyanofunctionalization via distonic-like species. This new strategy enables highly regio-, chemo-, and enantioselective hydrocyanation, deuterocyanation, and cyanocarboxylation of alkenes without stoichiometric reductants or oxidants under visible light irradiation. This protocol provides a new blueprint for the exploration of the transformation potential of alkene radical anions.

10.
BMC Genomics ; 25(1): 114, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273225

RESUMO

BACKGROUND: Theaceae, comprising 300 + species, holds significance in biodiversity, economics, and culture, notably including the globally consumed tea plant. Stewartia gemmata, a species of the earliest diverging tribe Stewartieae, is critical to offer insights into Theaceae's origin and evolutionary history. RESULT: We sequenced the complete organelle genomes of Stewartia gemmata using short/long reads sequencing technologies. The chloroplast genome (158,406 bp) exhibited a quadripartite structure including the large single-copy region (LSC), a small single-copy region (SSC), and a pair of inverted repeat regions (IRs); 114 genes encoded 80 proteins, 30 tRNAs, and four rRNAs. The mitochondrial genome (681,203 bp) exhibited alternative conformations alongside a monocyclic structure: 61 genes encoding 38 proteins, 20 tRNAs, three rRNAs, and RNA editing-impacting genes, including ATP6, RPL16, COX2, NAD4L, NAD5, NAD7, and RPS1. Comparative analyses revealed frequent recombination events and apparent rRNA gene gains and losses in the mitochondrial genome of Theaceae. In organelle genomes, the protein-coding genes exhibited a strong A/U bias at codon endings; ENC-GC3 analysis implies selection-driven codon bias. Transposable elements might facilitate interorganelle sequence transfer. Phylogenetic analysis confirmed Stewartieae's early divergence within Theaceae, shedding light on organelle genome characteristics and evolution in Theaceae. CONCLUSIONS: We studied the detailed characterization of organelle genomes, including genome structure, composition, and repeated sequences, along with the identification of lateral gene transfer (LGT) events and complexities. The discovery of a large number of repetitive sequences and simple sequence repeats (SSRs) has led to new insights into molecular phylogenetic markers. Decoding the Stewartia gemmata organellar genome provides valuable genomic resources for further studies in tea plant phylogenomics and evolutionary biology.


Assuntos
Genoma de Cloroplastos , Theaceae , Filogenia , Theaceae/genética , Genômica , Códon/genética , Cloroplastos/genética , RNA de Transferência/genética , Chá
11.
J Am Chem Soc ; 146(3): 1735-1741, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38095630

RESUMO

Regioselective C-H amination of simple arenes is highly desirable, but accessing meta-sites of ubiquitous arenes has proven challenging due to the lack of both electronic and spatial preference. This study demonstrates the successful use of various privileged nitrogen-containing functionalities found in pharmaceutical compounds to direct meta-C-H amination of arenes, overcoming the long-standing requirement for a redundant directing group. The remarkable advancements in functional group accommodation for precise regiochemical control were achieved through the discovery of an unprecedented organo-initiator and the strategic utilization of non-covalent interactions. This protocol has been successfully applied in the concise synthesis and late-stage derivatization of drug molecules, which would have been otherwise challenging to achieve.

12.
Pac Symp Biocomput ; 29: 521-533, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38160304

RESUMO

Advances in molecular characterization have reshaped our understanding of low-grade glioma (LGG) subtypes, emphasizing the need for comprehensive classification beyond histology. Lever-aging this, we present a novel approach, network-based Subnetwork Enumeration, and Analysis (nSEA), to identify distinct LGG patient groups based on dysregulated molecular pathways. Using gene expression profiles from 516 patients and a protein-protein interaction network we generated 25 million sub-networks. Through our unsupervised bottom-up approach, we selected 92 subnetworks that categorized LGG patients into five groups. Notably, a new LGG patient group with a lack of mutations in EGFR, NF1, and PTEN emerged as a previously unidentified patient subgroup with unique clinical features and subnetwork states. Validation of the patient groups on an independent dataset demonstrated the robustness of our approach and revealed consistent survival traits across different patient populations. This study offers a comprehensive molecular classification of LGG, providing insights beyond traditional genetic markers. By integrating network analysis with patient clustering, we unveil a previously overlooked patient subgroup with potential implications for prognosis and treatment strategies. Our approach sheds light on the synergistic nature of driver genes and highlights the biological relevance of the identified subnetworks. With broad implications for glioma research, our findings pave the way for further investigations into the mechanistic underpinnings of LGG subtypes and their clinical relevance.Availability: Source code and supplementary data are available at https://github.com/bebeklab/nSEA.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Prognóstico , Biologia Computacional , Glioma/genética , Glioma/patologia , Algoritmos , Mapas de Interação de Proteínas , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia
13.
Transl Cancer Res ; 12(10): 2582-2595, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37969391

RESUMO

Background: The aberrant expression of the classical tumor suppressor gene p16 is a frequent event in lung cancer mainly due to the hypermethylation of its 5'-cytosine-phosphate-guanine-3' island (Cgi). However, whether methylation happens in other regions and how p16 expression and function are affected are largely unknown. Methods: Clustered Regularly Interspaced Short Palindromic Repeats/dCas9 (CRISPR/dCas9) technology was used for methylation editing at specific site of p16. The effects of methylation editing were detected by 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethoxyphenyl)-2-(4-sulfopheny)-2H-tetrazolium, inner salt (MTS), transwell migration and wound healing tests. Chromatin immnoprecipitation-quantitative polymerase chain reaction (CHIP-qPCR) was performed to explore the impact of Cgi shore methylation on the binding abilities of transcription factors (TFs) including YY1, SP1, ZNF148 and OTX2 to p16 gene. A rescue experiment was performed to verify the regulatory effect of OTX2 on p16. The negative relationship between p16 expression and the methylation level of Cgi shore in non-promoter region was further verified with datasets from The Cancer Genome Atlas (TCGA) program and lung adenocarcinoma (LUAD) patients' samples. Results: The suppressive effect of p16 Cgi shore methylation on its expression was demonstrated in both HEK293 and A549 cells using CRISPR/dCas9-mediated specific site methylation editing. Methylation of the Cgi shore in the p16 non-promoter region significantly decreased its expression and promoted cell growth and migration. The ability of OTX2 bound to p16 was significantly reduced by 19.35% after methylation modification. Over-expression of OTX2 in A549 cells partly reversed the inhibitory effect of methylation on p16 expression by 19.04%. The verification results with TCGA and LUAD patients' samples supported that the p16 Cgi shore is a key methylation regulatory region. Conclusions: Our findings suggested that methylation of the Cgi shore in the p16 non-promoter region can hamper the transcriptional activity of OTX2, leading to a reduction in the expression of p16, which might contribute to the development of lung cancer.

14.
Sci Rep ; 13(1): 20535, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996510

RESUMO

A multi-class classification model for acute coronary syndrome (ACS) remains to be constructed based on multi-fluid metabolomics. Major confounders may exert spurious effects on the relationship between metabolism and ACS. The study aims to identify an independent biomarker panel for the multiclassification of HC, UA, and AMI by integrating serum and urinary metabolomics. We performed a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based metabolomics study on 300 serum and urine samples from 44 patients with unstable angina (UA), 77 with acute myocardial infarction (AMI), and 29 healthy controls (HC). Multinomial machine learning approaches, including multinomial adaptive least absolute shrinkage and selection operator (LASSO) regression and random forest (RF), and assessment of the confounders were applied to integrate a multi-class classification biomarker panel for HC, UA and AMI. Different metabolic landscapes were portrayed during the transition from HC to UA and then to AMI. Glycerophospholipid metabolism and arginine biosynthesis were predominant during the progression from HC to UA and then to AMI. The multiclass metabolic diagnostic model (MDM) dependent on ACS, including 2-ketobutyric acid, LysoPC(18:2(9Z,12Z)), argininosuccinic acid, and cyclic GMP, demarcated HC, UA, and AMI, providing a C-index of 0.84 (HC vs. UA), 0.98 (HC vs. AMI), and 0.89 (UA vs. AMI). The diagnostic value of MDM largely derives from the contribution of 2-ketobutyric acid, and LysoPC(18:2(9Z,12Z)) in serum. Higher 2-ketobutyric acid and cyclic GMP levels were positively correlated with ACS risk and atherosclerosis plaque burden, while LysoPC(18:2(9Z,12Z)) and argininosuccinic acid showed the reverse relationship. An independent multiclass biomarker panel for HC, UA, and AMI was constructed using the multinomial machine learning methods based on serum and urinary metabolite signatures.


Assuntos
Síndrome Coronariana Aguda , Infarto do Miocárdio , Humanos , Síndrome Coronariana Aguda/diagnóstico , Ácido Argininossuccínico , Cromatografia Líquida , Espectrometria de Massas em Tandem , Biomarcadores , Infarto do Miocárdio/diagnóstico , Angina Instável , GMP Cíclico
15.
Angew Chem Int Ed Engl ; 62(51): e202312102, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37936319

RESUMO

The exploration of value-added conversions of naturally abundant amino acids has received considerable attention from the synthetic community. Compared with the well-established asymmetric decarboxylative transformation, the asymmetric deaminative transformation of amino acids still remains a formidable challenge, mainly due to the lack of effective strategies for the C-N bond activation and the potential incompatibility with chiral catalysts. Here, we disclose a photoinduced Cu-catalyzed asymmetric deaminative coupling reaction of amino acids with arylboronic acids. This new protocol provides a series of significant chiral phenylacetamides in generally good yields and excellent stereoselectivity under mild and green conditions (42-85 % yields, up to 97 % ee). Experimental investigations and theoretical calculations were performed to reveal the crucial role of additional phenols in improving catalytic efficiency and enantiocontrol.

16.
MedComm (2020) ; 4(5): e387, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37799808

RESUMO

Currently, checkpoint inhibitor-based immunotherapy has emerged as prevailing treatment modality for diverse cancers. However, immunotherapy as a first-line therapy has not consistently yielded durable responses. Moreover, the risk of immune-related adverse events increases with combination regimens. Thus, the development of predictive biomarkers is needed to optimize individuals benefit, minimize risk of toxicities, and guide combination approaches. The greatest focus has been on tumor programmed cell death-ligand 1 (PD-L1), microsatellite instability (MSI), and tumor mutational burden (TMB). However, there remains a subject of debate due to thresholds variability and significant heterogeneity. Major unmet challenges in immunotherapy are the discovery and validation of predictive biomarkers. Here, we show the status of tumor PD-L1, MSI, TMB, and emerging data on novel biomarker strategies with oncogenic signaling and epigenetic regulation. Considering the exploration of peripheral and intestinal immunity has served as noninvasive alternative in predicting immunotherapy, this review also summarizes current data in systemic immunity, encompassing solute PD-L1 and TMB, circulating tumor DNA and infiltrating lymphocytes, routine emerging inflammatory markers and cytokines, as well as gut microbiota. This review provides up-to-date information on the evolving field of currently available biomarkers in predicting immunotherapy. Future exploration of novel biomarkers is warranted.

17.
Lab Chip ; 23(19): 4324-4333, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37702391

RESUMO

Particle separation plays a critical role in many biochemical analyses. In this article, we report a method of reverse flow enhanced inertia pinched flow fractionation (RF-iPFF) for particle separation. RF-iPFF separates particles by size based on the flow-induced inertial lift, and in the abruptly broadened segment, reverse flow is utilized to further enhance the separation distance between particles of different sizes. The separation performance can be significantly improved by reverse flow. Generally, compared with the case without reverse flow, this RF-iPFF technique can increase the particle throughput by about 10 times. To demonstrate the advantages of RF-iPFF, RF-iPFF was compared with traditional iPFF through a control experiment. RF-iPFF consistently outperformed iPFF across various conditions we studied. In addition, we use tumor cells spiked into the human whole blood to evaluate the separation performance of RF-iPFF.


Assuntos
Técnicas Analíticas Microfluídicas , Humanos , Tamanho da Partícula , Técnicas Analíticas Microfluídicas/métodos , Fracionamento Químico/métodos , Microesferas
18.
Angew Chem Int Ed Engl ; 62(41): e202309460, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37615886

RESUMO

Radical single carbonylation reactions with CO constitute a direct and robust strategy toward various carbonyl compounds from readily available chemicals, and have been extensively studied over the past decades. However, realizing highly selective catalytic systems for controlled radical double carbonylation reactions has remained a substantial challenge, particularly for the more advanced multicomponent variants, despite their great potential value. Herein, we report a visible-light-driven radical relay five-component radical double aminocarbonylation reaction of unactivated alkenes using CO under metal-free conditions. This protocol provides direct access to valuable γ-trifluoromethyl α-ketoamides with good yields and high chemoselectivity. Crucial was the identification of distinct dual roles of amine coupling partners, sequentially acting as electron donors for the formation of photoactive electron donor-acceptor (EDA) complexes with radical precursors and then as a CO acceptor via nitrogen radical cations to form carbamoyl radicals. Cross-coupling of carbamoyl radicals with the acyl radicals that are formed in an alkene-based relay process affords double aminocarbonylation products.

19.
Magn Reson Imaging ; 104: 1-8, 2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37553044

RESUMO

PURPOSE: Patients with metabolic dysfunction-associated steatohepatitis (MASH) and significant fibrosis (fibrosis stage≥2), known as Fibro-MASH, are at increased risk of liver-related outcomes and lower rates of spontaneous disease regression. The aim was to investigate three-dimensional MR elastography (3D-MRE) combining proton-density fat fraction (PDFF) as a means of identifying Fibro-MASH. METHODS: Forty-eight New Zealand rabbits were fed a high-fat/cholesterol or standard diet to obtain different disease activity and fibrosis stages. Shear stiffness (SS) and Damping Ratio (DR) were derived from 3D-MRE, whereas PDFF was from a volumetric 3D imaging sequence. Steatosis grade, metabolic dysfunction-associated steatotic liver disease activity score (MAS), and fibrosis stage were diagnosed histologically. Serum markers of fibrosis and inflammation were also measured. Correlation and comparison analysis, Receiver operating characteristic curves (ROC), Delong test, logistic regression analysis, and Net reclassification improvement (NRI) were performed. RESULTS: PDFF correlated with steatosis grade (rho = 0.853). SS increased with developed liver fibrosis (rho = 0.837). DR correlated with MAS grade (rho = 0.678). The areas under the ROC (AUROCs) of SS for fibrosis grading were 0.961 and 0.953 for ≥F2, and ≥ F3, respectively. All the biochemical parameters were considered but excluded from the logistic regression analysis to identify Fibro-MASH. FF, SS, and DR were finally included in the further analysis. The three-parameter model combining PDFF, SS, and DR showed significant improvement in NRI over the model combining SS and PDFF (AUROC 0.973 vs. 0.906, P = 0.081; NRI 0.28, P < 0.05). CONCLUSION: 3D-MRE combining PDFF may characterize the state of fat content, disease activity and fibrosis, thus precisely identify Fibro-MASH.

20.
Nat Commun ; 14(1): 4825, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563134

RESUMO

Catalytic enantioselective introduction of a propargyl group constitutes one of the most important carbon-carbon forming reactions, as it is versatile to be transformed into diverse functional groups and frequently used in the synthesis of natural products and biologically active molecules. Stereoconvergent transformations of racemic propargyl precursors to a single enantiomer of products via propargyl radicals represent a powerful strategy and provide new reactivity. However, only few Cu- or Ni-catalyzed protocols have been developed with limited reaction modes. Herein, a photoredox/cobalt-catalyzed regio-, diastereo- and enantioselective propargyl addition to aldehydes via propargyl radicals is presented, enabling construction of a broad scope of homopropargyl alcohols that are otherwise difficult to access in high efficiency and stereoselectivity from racemic propargyl carbonates. Mechanistic studies and DFT calculations provided evidence for the involvement of propargyl radicals, the origin of the stereoconvergent process and the stereochemical models.

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