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1.
Mol Cell ; 81(22): 4747-4756.e7, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34648747

RESUMO

The CRISPR-Cas12a system shows unique features compared with widely used Cas9, making it an attractive and potentially more precise alternative. However, the adoption of this system has been hindered by its relatively low editing efficiency. Guided by physical chemical principles, we covalently conjugated 5' terminal modified CRISPR RNA (crRNA) to a site-specifically modified Cas12a through biorthogonal chemical reaction. The genome editing efficiency of the resulting conjugated Cas12a complex (cCas12a) was substantially higher than that of the wild-type complex. We also demonstrated that cCas12a could be used for precise gene knockin and multiplex gene editing in a chimeric antigen receptor T cell preparation with efficiency much higher than that of the wild-type system. Overall, our findings indicate that covalently linking Cas nuclease and crRNA is an effective approach to improve the Cas12a-based genome editing system and could potentially provide an insight into engineering other Cas family members with low efficiency as well.


Assuntos
Proteínas de Bactérias/genética , Proteínas Associadas a CRISPR/genética , Sistemas CRISPR-Cas , Endodesoxirribonucleases/genética , Edição de Genes , Receptores de Antígenos Quiméricos/metabolismo , Acidaminococcus , Animais , DNA/química , DNA/metabolismo , Endonucleases/metabolismo , Escherichia coli/metabolismo , Técnicas de Introdução de Genes , Técnicas Genéticas , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Técnicas In Vitro , Células K562 , Camundongos , Mutagênese , RNA/metabolismo , Espectrometria de Massas em Tandem
2.
Nat Chem Biol ; 20(6): 721-731, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38302606

RESUMO

Protein labeling approaches are important to study proteins in living cells, and genome editing tools make it possible to tag endogenous proteins to address the concerns associated with overexpression. Here we established RNA editing-mediated noncanonical amino acids (ncAAs) protein tagging (RENAPT) to site-specifically label endogenous proteins with ncAAs in living cells. RENAPT labels protein in a temporary and nonheritable manner and is not restricted by protospacer adjacent motif sequence. Using a fluorescent ncAA or ncAA with a bio-orthogonal reaction handle for subsequent dye labeling, we demonstrated that a variety of endogenous proteins can be imaged at their specific subcellular locations. In addition, two proteins can be tagged individually and simultaneously using two different ncAAs. Furthermore, endogenous ion channels and neuron-specific proteins can be real-time labeled in primary neurons. Thus, RENAPT presents a promising platform with broad applicability for tagging endogenous proteins in living cells to study their localization and functions.


Assuntos
Código Genético , Edição de RNA , Humanos , Animais , Neurônios/metabolismo , Células HEK293 , Aminoácidos/química , Aminoácidos/metabolismo , Aminoácidos/genética , Proteínas/química , Proteínas/genética , Proteínas/metabolismo , Corantes Fluorescentes/química
3.
Mol Med ; 30(1): 53, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649840

RESUMO

OBJECTIVE: Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are associated with significant mortality rates. The role of Fcgr2b in the pathogenesis of ALI/ARDS is not fully elucidated. This study aimed to investigate the functions of Fcgr2b in ALI/ARDS and explore its underlying mechanisms. METHODS: Methods: In this study, rat models of ARDS and pulmonary microvascular endothelial cell (PMVEC) injury models were established through the administration of lipopolysaccharide (LPS). The expression levels of Fcgr2b and Elk1 were quantified in both LPS-induced ARDS rats and PMVECs. Subsequent gain- and loss-of-function experiments were conducted, followed by comprehensive assessments of lung tissue for pathomorphological changes, edema, glycogen storage, fibrosis, and infiltration of inflammatory cells. Additionally, bronchoalveolar lavage fluid was analyzed for T-helper 17 (Th17) cell infiltration, inflammatory response, and microvascular permeability to evaluate lung injury severity in ARDS models. Furthermore, the activity, cytotoxicity, apoptosis, and angiogenic potential of PMVECs were assessed to gauge cell injury. The interaction between Elk1 and Fcgr2b was also examined to confirm their regulatory relationship. RESULTS: In the context of LPS-induced ARDS and PMVEC injury, Fcgr2b expression was markedly reduced, whereas Elk1 expression was elevated. Overexpression of Fcgr2b led to a decrease in Th17 cell infiltration and mitigated lung tissue damage in ARDS models, in addition to reducing LPS-induced injury in PMVECs. Elk1 was found to suppress Fcgr2b transcription through the recruitment of histone 3 lysine 9 trimethylation (H3K9me3). Knockdown of Elk1 diminished Th17 cell infiltration and lung tissue damage in ARDS models, and alleviated LPS-induced injury in PMVECs, effects that were reversed upon Fcgr2b upregulation. CONCLUSION: Elk1 negatively regulates Fcgr2b transcription, thereby augmenting the inflammatory response and exacerbating lung injury in LPS-induced ALI/ARDS.


Assuntos
Lesão Pulmonar Aguda , Modelos Animais de Doenças , Células Endoteliais , Lipopolissacarídeos , Receptores de IgG , Síndrome do Desconforto Respiratório , Proteínas Elk-1 do Domínio ets , Animais , Masculino , Ratos , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/etiologia , Células Endoteliais/metabolismo , Proteínas Elk-1 do Domínio ets/metabolismo , Proteínas Elk-1 do Domínio ets/genética , Pulmão/patologia , Pulmão/metabolismo , Ratos Wistar , Receptores de IgG/metabolismo , Receptores de IgG/genética , Síndrome do Desconforto Respiratório/metabolismo , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/genética , Células Th17/metabolismo , Células Th17/imunologia , Transcrição Gênica
4.
Angew Chem Int Ed Engl ; 63(16): e202400599, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38407550

RESUMO

Proteins capable of switching between distinct active states in response to biochemical cues are ideal for sensing and controlling biological processes. Activatable CRISPR-Cas systems are significant in precise genetic manipulation and sensitive molecular diagnostics, yet directly controlling Cas protein function remains challenging. Herein, we explore anti-CRISPR (Acr) proteins as modules to create synthetic Cas protein switches (CasPSs) based on computational chemistry-directed rational protein interface engineering. Guided by molecular fingerprint analysis, electrostatic potential mapping, and binding free energy calculations, we rationally engineer the molecular interaction interface between Cas12a and its cognate Acr proteins (AcrVA4 and AcrVA5) to generate a series of orthogonal protease-responsive CasPSs. These CasPSs enable the conversion of specific proteolytic events into activation of Cas12a function with high switching ratios (up to 34.3-fold). These advancements enable specific proteolysis-inducible genome editing in mammalian cells and sensitive detection of viral protease activities during virus infection. This work provides a promising strategy for developing CRISPR-Cas tools for controllable gene manipulation and regulation and clinical diagnostics.


Assuntos
Proteínas Associadas a CRISPR , Edição de Genes , Animais , Sistemas CRISPR-Cas/genética , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Proteínas Associadas a CRISPR/genética , Proteínas Associadas a CRISPR/metabolismo , Endopeptidases/metabolismo , Proteases Virais/genética , Proteases Virais/metabolismo , Mamíferos/metabolismo
5.
Cell Mol Biol Lett ; 28(1): 91, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37946128

RESUMO

OBJECTIVE: To investigate the mechanism of action of Srg3 in acute lung injury caused by sepsis. METHODS: First, a sepsis-induced acute lung injury rat model was established using cecal ligation and puncture (CLP). RNA sequencing (RNA-seq) was used to screen for highly expressed genes in sepsis-induced acute lung injury (ALI), and the results showed that Srg3 was significantly upregulated. Then, SWI3-related gene 3 (Srg3) was knocked down using AAV9 vector in vivo, and changes in ALI symptoms in rats were analyzed. In vitro experiments were conducted by establishing a cell model using lipopolysaccharide (LPS)-induced BEAS-2B cells and coculturing them with phorbol 12-myristate 13-acetate (PMA)-treated THP-1 cells to analyze macrophage polarization. Next, downstream signaling pathways regulated by Srg3 and transcription factors involved in regulating Srg3 expression were analyzed using the KEGG database. Finally, gain-of-loss functional validation experiments were performed to analyze the role of downstream signaling pathways regulated by Srg3 and transcription factors involved in regulating Srg3 expression in sepsis-induced acute lung injury. RESULTS: Srg3 was significantly upregulated in sepsis-induced acute lung injury, and knocking down Srg3 significantly improved the symptoms of ALI in rats. Furthermore, in vitro experiments showed that knocking down Srg3 significantly weakened the inhibitory effect of LPS on the viability of BEAS-2B cells and promoted alternative activation phenotype (M2) macrophage polarization. Subsequent experiments showed that Srg3 can regulate the activation of the NF-κB signaling pathway and promote ferroptosis. Specific activation of the NF-κB signaling pathway or ferroptosis significantly weakened the effect of Srg3 knockdown. It was then found that Srg3 can be transcriptionally activated by interferon regulatory factor 7 (Irf7), and specific inhibition of Irf7 significantly improved the symptoms of ALI. CONCLUSIONS: Irf7 transcriptionally activates the expression of Srg3, which can promote ferroptosis and activate classical activation phenotype (M1) macrophage polarization by regulating the NF-κB signaling pathway, thereby exacerbating the symptoms of septic lung injury.


Assuntos
Lesão Pulmonar Aguda , Ferroptose , Sepse , Animais , Ratos , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Fator Regulador 7 de Interferon/metabolismo , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Sepse/complicações , Fatores de Transcrição/metabolismo
6.
Angew Chem Int Ed Engl ; 61(30): e202205570, 2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35644909

RESUMO

Structurally diverse acylations have been identified as post-translational modifications (PTMs) on histone lysine residues, but their functions and regulations remain largely unknown. Interestingly, in nature, a lysine acylation analog, pyrrolysine, is introduced as a co-translational modification (CTM) through genetic encoding. To explore this alternative life form, we created a model organism Saccharomyces cerevisiae containing site-specific lysine CTMs (acetyl-lysine, crotonyl-lysine, or another synthetic analog) at histone H3K56 using non-canonical amino acid mutagenesis to afford a chemically modified nucleosome in lieu of their own in vivo. We further demonstrated that acetylation of histone H3K56 partly tends to provide a more favorable chromatin environment for DNA repair in yeast compared to crotonylation and crosstalk with other PTMs differently. This study provides a potentially universal approach to decipher the consequences of different histone lysine PTMs in eukaryotes.


Assuntos
Histonas , Nucleossomos , Acetilação , Histonas/química , Lisina/química , Nucleossomos/metabolismo , Processamento de Proteína Pós-Traducional , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
7.
J Cardiovasc Pharmacol ; 77(2): 130-141, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33165141

RESUMO

ABSTRACT: Hydrogen sulfide (H2S), generally known as a new gas signal molecule after nitric oxide and carbon monoxide, has been found as an important endogenous gasotransmitter in the last few decades, and it plays a significant role in the cardiovascular system both pathologically and physiologically. In recent years, there is growing evidence that H2S provides myocardial protection against myocardial ischemia-reperfusion injury (MIRI), which resulted in an ongoing focus on the possible mechanisms of action accounting for the H2S cardioprotective effect. At present, lots of mechanisms of action have been verified through in vitro and in vivo models of I/R injury, such as S-sulfhydrated modification, antiapoptosis, effects on microRNA, bidirectional effect on autophagy, antioxidant stress, or interaction with NO and CO. With advances in understanding of the molecular pathogenesis of MIRI and pharmacology studies, the design, the development, and the pharmacological characterization of H2S donor drugs have made great important progress. This review summarizes the latest research progress on the role of H2S in MIRI, systematically explains the molecular mechanism of H2S affecting MIRI, and provides a new idea for the formulation of a myocardial protection strategy in the future.


Assuntos
Sistema Cardiovascular/metabolismo , Gasotransmissores/metabolismo , Sulfeto de Hidrogênio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Animais , Monóxido de Carbono/metabolismo , Sistema Cardiovascular/efeitos dos fármacos , Sistema Cardiovascular/patologia , Sistema Cardiovascular/fisiopatologia , Morte Celular , Gasotransmissores/uso terapêutico , Humanos , Sulfeto de Hidrogênio/uso terapêutico , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Miocárdio/patologia , Óxido Nítrico/metabolismo , Transdução de Sinais
8.
Angew Chem Int Ed Engl ; 59(47): 20895-20899, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33448579

RESUMO

Currently CRISPR/Cas9 is a widely used efficient tool for gene editing. Precise control over the CRISPR/Cas9 system with high temporal and spatial resolution is essential for studying gene regulation and editing. Here, we synthesized a novel light-controlled crRNA by coupling vitamin E and a photolabile linker at the 5' terminus to inactivate the CRISPR/Cas9 system. The vitamin E modification did not affect ribonucleoprotein (RNP) formation of Cas9/crRNA/tracrRNA complexes but did inhibit the association of RNP with the target DNA. Upon light irradiation, vitamin E-caged crRNA was successfully activated to achieve light-induced genome editing of vascular endothelial cell-growth factor A (VEGFA) in human cells through a T7E1 assay and Sanger sequencing as well as gene knockdown of EGFP expression in EGFP stably expressing cells. This new caging strategy for crRNA could provide new methods for spatiotemporal photoregulation of CRISPR/Cas9-mediated gene editing.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , RNA/genética , DNA/genética , DNA/metabolismo , Células HEK293 , Humanos , RNA/química , RNA/efeitos da radiação , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Raios Ultravioleta , Vitamina E/análogos & derivados , Vitamina E/efeitos da radiação
9.
BMC Cardiovasc Disord ; 19(1): 278, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791258

RESUMO

BACKGROUND: Diabetes mellitus (DM) has been demonstrated to be a strong risk factor for development and perpetuation of atrial fibrillation (AF). However, how DM and glycemic control affect the pathogenesis of AF has not been sufficiently investigated, especially for the atrial structural remodeling. METHODS: A total of 86 patients undergoing coronary artery bypass graft surgery were enrolled in this study, with atrium sample collected in the operation. The patients were divided into the DM group (n = 40) and the control group (n = 46) accordingly. Demographics, clinical data were collected and compared. Echocardiography, Masson staining and Western blotting were conducted to evaluate atrial structural remodeling. RESULTS: There was no significant difference between the two groups in baseline characteristics (all P > 0.05). Fast blood glucose and HbA1c of DM group were significantly higher than the control group (P < 0.001). Echocardiography results demonstrated that the left atrium diameter (LAD) and left atrium volume index (LAVI) of DM group was significantly higher than the control group (P < 0.001). Masson staining showed that the collagen volume fraction (CVF), a quantitative indicator of fibrosis, was significantly higher in DM patients (P = 0.03). Western blot results indicated that the Collagen I of DM group was more expressed in the DM group than the control group (P < 0.001). Univariate linear regression revealed that the HbA1c level was significantly associated with both LAD (Y = 1.139X + 25.575, P < 0.001, R2 = 0.291) and CVF (Y = 0.444X + 29.648, P = 0.009, R2 = 0.078). CONCLUSIONS: DM was associated with atrial structural remodeling, including atrium enlargement and atrial fibrosis, which might be attributed to poor glycemic control.


Assuntos
Fibrilação Atrial/fisiopatologia , Função do Átrio Esquerdo , Remodelamento Atrial , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/etiologia , Biomarcadores/sangue , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Fibrose , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
10.
Chin J Cancer Res ; 31(4): 673-685, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31564810

RESUMO

OBJECTIVE: To evaluate the imaging potential of a novel near-infrared (NIR) probe conjugated to COC183B2 monoclonal antibodies (MAb) in ovarian cancer (OC). METHODS: The expression of OC183B2 antigen in OC was determined by immunohistochemical (IHC) staining using tissue microarrays with the H-score system and immunofluorescence (IF) staining of tumor cell lines. Imaging probes with the NIR fluorescent dye cyanine 7 (Cy7) conjugated to COC183B2 Mab were chemically engineered. OC183B2-positive human OC cells (SKOV3-Luc) were injected subcutaneously into BALB/c nude mice. Bioluminescent imaging (BLI) was performed to detect tumor location and growth. COC183B2-Cy7 at 1.1, 3.3, 10, or 30 µg were used for in vivo fluorescence imaging, and phosphate-buffered saline (PBS), free Cy7 dye and mouse isotype immunoglobulin G (IgG)-Cy7 (delivered at the same doses as COC183B2-Cy7) were used as controls. RESULTS: The expression of OC183B2 with a high H-score was more prevalent in OC tissue than fallopian tube (FT) tissue. Among 417 OC patients, the expression of OC183B2 was significantly correlated with the histological subtype, histological grade, residual tumor size, relapse state and survival status. IF staining demonstrated that COC183B2 specifically expressed in SKOV3 cells but not HeLa cells. In vivo NIR fluorescence imaging indicated that COC183B2-Cy7 was mainly distributed in the xenograft and liver with optimal tumor-to-background (T/B) ratios in the xenograft at 30 µg dose. The highest fluorescent signals in the tumor were observed at 96 h post-injection (hpi). Ex vivo fluorescence imaging revealed the fluorescent signals mainly from the tumor and liver. IHC analysis confirmed that xenografts were OC183B2 positive. CONCLUSIONS: COC183B2 is a good candidate for NIR fluorescence imaging and imaging-guided surgery in OC.

11.
Heart Lung Circ ; 23(10): 905-12, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25017041

RESUMO

BACKGROUND: Ischaemic mitral regurgitation (IMR) is commonly manifested after coronary artery disease, but it is still controversial as to whether coronary artery bypass grafting (CABG) alone improves postoperative outcome. OBJECTIVES: A focussed clinical question was designed and a meta-analysis of published studies was performed to identify the impact of mitral valve repair (MVR) in patients with IMR undergoing CABG versus those undergoing CABG alone. METHODS: Using the Medline database, the Cochrane clinical trials database and online clinical trial databases, we reviewed all RCTs and observational studies examining the impact of MVR and CABG in treating patients with IMR. We searched for literature published before September 2013 and earlier. RESULTS: This analysis identified five studies which examined the impact of CABG alone versus combined CABG and MVR in treating patients with IMR, involving 1038 patients, with 423 patients undergoing CABG alone and 615 were performed combined CABG and MVR procedures. There was significant improvement in postoperative mitral regurgitation (MR) grade in combined group, comparing with CABG alone group (WMD: 1.34, 95% CI: 0.47 to 2.21, p = 0.003), but no significant differences were noted between the CABG plus MVR group and CABG alone group in terms of in-hospital mortality (OR: 0.84, 95% CI: 0.44 to 1.61, p = 0.60), MR grade improvement rate (OR: 0.19, 95% CI: 0.02 to 1.66, p = 0.13), postoperative mean NYHA functional class (WMD: 0.33, 95% CI: -0.29 to 0.94, p = 0.30) and five-year survival (OR: 0.77, 95% CI: 0.34 to 1.73, p = 0.53). CONCLUSIONS: Compared with CABG alone, patients who underwent combined CABG and MVR procedures showed a greater improvement in postoperative MR grade, but in terms of in-hospital mortality, MR grade improvement rate, postoperative mean NYHA functional class and five-year survival, adding MVR to CABG surgery lacks evidence to show its superiority.


Assuntos
Ponte de Artéria Coronária , Anuloplastia da Valva Mitral , Insuficiência da Valva Mitral/cirurgia , Isquemia Miocárdica/cirurgia , Insuficiência Cardíaca/fisiopatologia , Mortalidade Hospitalar , Humanos , Índice de Gravidade de Doença , Taxa de Sobrevida , Resultado do Tratamento
12.
Mitochondrial DNA B Resour ; 8(6): 678-681, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346171

RESUMO

We assembled and characterized the complete chloroplast genome sequence of Chrysojasminum subhumile (W.W.Sm.) Banfi & Galasso 2014, a valuable horticultural and medicinal plant species. The total genome size was 159,918 bp in length and the GC content was 37.4%. It displayed a circular structure and could be divided into a large single-copy region, a small single-copy region, and a pair of inverted repeat regions. The genome encoded a total of 131 unique genes, including 82 protein-coding genes, 41 tRNA genes, and eight rRNA genes. Among these genes, 17 contained a single intron, and two genes had two introns. Phylogenetic analysis results showed that C. subhumile was closely related to Jasminum.

13.
Front Pharmacol ; 14: 1115221, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874021

RESUMO

Background: Recently, PANoptosis has aroused the interest of researchers for its role in cancers. However, the studies that investigated PANoptosis in lung cancer are still few. Methods: The public data were mainly collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus database. R software was utilized for the analysis of public data. Quantitative real-time (qRT) polymerase chain reaction (PCR) was used to measure the RNA level of FADD. The cell proliferation ability was evaluated using the CCK8, colony formation, and 5-ethynyl-2'-deoxyuridine (EdU) assays. Western blot was used to detect the protein level of specific molecules. Flow cytometry analysis and TUNEL staining were used to evaluate cell apoptosis. Results: In our study, we collected the PANoptosis-related genes from previous studies. Through series analysis, we identified the FADD, an adaptor of PANoptosis and apoptosis, for further analysis. Results showed that FADD is one of the prominent risk factors in lung cancer, mainly localized in nucleoplasm and cytosol. We next performed immune infiltration analysis and biological enrichment to illustrate the underlying cause of FADD in lung cancer. Subsequently, we discovered that the patients with a high level of FADD might respond worse to immunotherapy but better to AICAR, bortezomib, docetaxel, and gemcitabine. In vitro experiments indicated that inhibiting FADD could reduce significantly the ability of cancerous lung cells to proliferate. Meanwhile, we found that the knockdown of FADD promotes the apoptosis and pyroptosis. Ultimately, a prognosis signature was identified based on the FADD-regulated genes, which showed satisfactory prediction efficiency on patients with lung cancer. Conclusion: Our result can provide a novel direction for future studies focused on the role of PANoptosis in lung cancer.

14.
Materials (Basel) ; 16(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37297092

RESUMO

Traditional silicate cement materials produce a large amount of CO2 during production, making it urgent to seek alternatives. Alkali-activated slag cement is a good substitute, as its production process has low carbon emissions and energy consumption, and it can comprehensively utilize various types of industrial waste residue while possessing superior physical and chemical properties. However, the shrinkage of alkali-activated concrete can be larger than that of traditional silicate concrete. To address this issue, the present study utilized slag powder as the raw material, sodium silicate (water glass) as the alkaline activator, and incorporated fly ash and fine sand to study the dry shrinkage and autogenous shrinkage values of alkali cementitious material under different content. Furthermore, combined with the change trend of pore structure, the impact of their content on the drying shrinkage and autogenous shrinkage of alkali-activated slag cement was discussed. Based on the author's previous research, it was found that by sacrificing a certain mechanical strength, adding fly ash and fine sand can effectively reduce the drying shrinkage and autogenous shrinkage values of alkali-activated slag cement. The higher the content, the greater the strength loss of the material and the lower the shrinkage value. When the fly ash content was 60%, the drying shrinkage and autogenous shrinkage of the alkali-activated slag cement mortar specimens decreased by about 30% and 24%, respectively. When the fine sand content was 40%, the drying shrinkage and autogenous shrinkage of the alkali-activated slag cement mortar specimens decreased by about 14% and 4%, respectively.

15.
STAR Protoc ; 3(2): 101321, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35496795

RESUMO

We recently developed a system to create human chimeric antigen receptor (CAR)-T cells using conjugated Cas12a (cCas12a) in which Cas12a is covalently linked to its CRISPR RNA (crRNA). This protocol describes site-specific modification of Cas12a and the preparation of Cas12a-crRNA complex using bio-orthogonal chemistry, followed by CAR-T cell generation through electroporation and AAV infection. This system shows robust editing efficiency in human cells and can be used for precisely targeted, highly efficient integration of CAR genes into T cell genome. For complete details on the use and execution of this protocol, please refer to Ling et al. (2021).


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Humanos
16.
Nat Commun ; 13(1): 1204, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260581

RESUMO

The mechanism underlying unwanted structural variations induced by CRISPR-Cas9 remains poorly understood, and no effective strategy is available to inhibit the generation of these byproducts. Here we find that the generation of a high level of translocations is dependent on repeated cleavage at the Cas9-targeting sites. Therefore, we employ a strategy in which Cas9 is fused with optimized TREX2 to generate Cas9TX, a Cas9 exo-endonuclease, which prevents perfect DNA repair and thereby avoids repeated cleavage. In comparison with CRISPR-Cas9, CRISPR-Cas9TX greatly suppressed translocation levels and enhanced the editing efficiency of single-site editing. The number of large deletions associated with Cas9TX was also reduced to very low level. The application of CRISPR-Cas9TX for multiplex gene editing in chimeric antigen receptor T cells nearly eliminated deleterious chromosomal translocations. We report the mechanism underlying translocations induced by Cas9, and propose a general strategy for reducing chromosomal abnormalities induced by CRISPR-RNA-guided endonucleases.


Assuntos
Proteína 9 Associada à CRISPR , Edição de Genes , Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas/genética , Endonucleases/genética , Endonucleases/metabolismo , Humanos , RNA Guia de Cinetoplastídeos/química , RNA Guia de Cinetoplastídeos/genética , Translocação Genética
17.
Mol Med Rep ; 22(3): 1759-1766, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32705232

RESUMO

Diabetes mellitus (DM) facilitates atrial fibrosis and increases the risk of atrial fibrillation (AF). The underlying mechanism of DM in causing AF remains mostly unknown and potential therapeutic targets for DM­induced AF are rarely reported. Hydrogen sulfide (H2S) has drawn considerable attention in recent years for its potential as a cardiovascular protector. Thus, the aim of the present study was to investigate the effect of H2S on DM­induced AF and the mechanism of action. Sprague­Dawley rats were divided into four groups, including the control group, the DM group, the H2S group and the DM+H2S group. The DM group and the DM+H2S group were administered streptozotocin to induce DM, whereas the other two groups were given citrate buffer as a control. The H2S group and the DM+H2S group were administered with an intraperitoneal injection of sodium hydrosulfide (precursor of H2S). AF inducibility, AF duration, atrial fibrosis and vital protein expression of oxidative stress were compared among the four groups. The DM group showed significantly higher AF incidence rates and duration (P<0.05). Histology results demonstrated severe atrial fibrosis in the DM group, and the PI3K/Akt/endothelial nitric oxide synthase (eNOS) pathway was significantly downregulated (P<0.05). However, when H2S was administered, the rats showed lower AF incidence and duration compared with the DM group. Additionally, H2S was able to mitigate the atrial fibrosis induced by DM, as well as the proliferation and migration of cardiac fibroblasts, as demonstrated by an MTT assay and real­time cell analyzer migration experiment. Western blotting showed that the expression levels of the PI3K/Akt/eNOS pathway in the DM+H2S group were significantly upregulated compared with those of the DM group (P<0.05). In summary, DM status can lead to the structural remodeling of atrial fibrosis, facilitating AF incidence and persistence. Administration of H2S does not affect the glucose level, but can significantly mitigate atrial fibrosis and reduce the incidence of AF induced by DM, probably via activation of the PI3K/Akt/eNOS pathway.


Assuntos
Fibrilação Atrial/prevenção & controle , Diabetes Mellitus Experimental/tratamento farmacológico , Sulfeto de Hidrogênio/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Remodelação Vascular/efeitos dos fármacos , Animais , Fibrilação Atrial/etiologia , Fibrilação Atrial/metabolismo , Técnicas de Cultura de Células , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Sulfeto de Hidrogênio/farmacologia , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Estreptozocina , Resultado do Tratamento
18.
Chem Commun (Camb) ; 56(54): 7515-7518, 2020 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-32510061

RESUMO

The CRISPR-Cas9 system enables facile and efficient genome engineering in living cells and organisms. We report a Cas9-RNA conjugation strategy to afford minimal crRNA containing only the guide sequence for the target gene, which may simplify and reduce the cost for large-scale and high-throughput crRNA synthesis and lead to new insights into the design of CRISPR family complexes for diverse purposes.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , RNA Guia de Cinetoplastídeos/metabolismo , Sequência de Bases , Proteína 9 Associada à CRISPR/química , Cristalografia por Raios X , Edição de Genes/métodos , Células HEK293 , Humanos , Conformação de Ácido Nucleico , RNA Guia de Cinetoplastídeos/química , Projetos de Pesquisa , Streptococcus pyogenes/metabolismo
19.
Biomed Res Int ; 2020: 7458451, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33294452

RESUMO

BACKGROUND: Although the neutrophil percentage-to-albumin ratio (NPAR) has proven to be a robust systemic inflammation-based predictor of mortality in a wide range of diseases, the prognostic value of the NPAR in critically ill patients with cardiogenic shock (CS) remains unknown. This study aimed at investigating the association between the admission NPAR and clinical outcomes in CS patients using real-world data. METHODS: Critically ill patients diagnosed with CS in the Medical Information Mart for Intensive Care-III (MIMIC-III) database were included in our study. The study endpoints included all-cause in-hospital, 30-day, and 365-day mortality in CS patients. First, the NPAR was analyzed as a continuous variable using restricted cubic spline Cox regression models. Second, X-tile analysis was used to calculate the optimal cut-off values for the NPAR and divide the cohort into three NPAR groups. Moreover, multivariable Cox regression analyses were used to assess the association of the NPAR groups with mortality. RESULTS: A total of 891 patients hospitalized with CS were enrolled in this study. A nonlinear relationship between the NPAR and in-hospital and 30-day mortality was observed (all P values for nonlinear trend<0.001). According to the optimal cut-off values by X-tile, NPARs were divided into three groups: group I (NPAR < 25.3), group II (25.3 ≤ NPAR < 34.8), and group III (34.8 ≤ NPAR). Multivariable Cox analysis showed that higher NPAR was independently associated with increased risk of in-hospital mortality (group III vs. group I: hazard ratio [HR] 2.60, 95% confidence interval [CI] 1.72-3.92, P < 0.001), 30-day mortality (group III vs. group I: HR 2.42, 95% CI 1.65-3.54, P < 0.001), and 365-day mortality (group III vs. group I: HR 6.80, 95% CI 4.10-11.26, P < 0.001) in patients with CS. CONCLUSIONS: Admission NPAR was independently associated with in-hospital, 30-day, and 365-day mortality in critically ill patients with CS.


Assuntos
Albuminas/metabolismo , Neutrófilos/patologia , Choque Cardiogênico/mortalidade , Idoso , Área Sob a Curva , Estudos de Coortes , Feminino , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Admissão do Paciente , Análise de Sobrevida , Resultado do Tratamento
20.
J Thorac Dis ; 12(3): 592-604, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32274125

RESUMO

BACKGROUND: The optimal surgical strategy for early-stage non-small cell lung cancer (NSCLC) with visceral pleural invasion (VPI) remains unclear. Due to limited prospective comparative data for these surgical modalities, the objective of the current study was to compare the long-term survival outcomes of sublobectomy (Sub) versus lobectomy (Lob) for NSCLC with a tumor size ≤2 cm and VPI. METHODS: Patients with early-stage NSCLC characterized by VPI diagnosed between 2004 and 2013 were identified from the Surveillance, Epidemiology, and End Results (SEER) program. The baseline demographic and cancer characteristics, treatment information as well as survival outcome data were extracted from the SEER database, and confounders were balanced by propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) analyses. Lung disease-specific survival (DSS) and overall survival (OS) rates were compared with Cox proportional hazards (PH) regression models based on the unmatched cohort, the propensity-based matched cohort, and the IPTW cohort. RESULTS: Of the 1,386 patients enrolled, 1,000 (72.15%) and 386 (27.85%) underwent lobectomy and sublobectomy, respectively. The 5-year DSS rate was 78.64% for the lobectomy group and 59.47% for the sublobectomy group. Cox regression models demonstrated that the operation type (Sub vs. Lob) was an independent prognostic factor for early-stage NSCLC with VPI based on the three different cohorts. Patients who underwent lobectomy showed better long-term DSS and OS rates than those treated with sublobectomy after PSM [DSS: hazard ratio (HR) 0.689, 95% confidence interval (CI): 0.490-0.968, P=0.032; OS: HR 0.723, 95% CI: 0.549-0.953, P=0.021]. The IPTW analysis yielded similar results. CONCLUSIONS: Lobectomy showed superior long-term survival compared with sublobectomy in patients with early-stage NSCLC with a tumor size ≤2 cm and VPI.

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