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1.
Mol Cell ; 83(15): 2768-2780.e6, 2023 08 03.
Article in English | MEDLINE | ID: mdl-37402371

ABSTRACT

Type V CRISPR-associated systems (Cas)12 family nucleases are considered to have evolved from transposon-associated TnpB, and several of these nucleases have been engineered as versatile genome editors. Despite the conserved RNA-guided DNA-cleaving functionality, these Cas12 nucleases differ markedly from the currently identified ancestor TnpB in aspects such as guide RNA origination, effector complex composition, and protospacer adjacent motif (PAM) specificity, suggesting the presence of earlier evolutionary intermediates that could be mined to develop advanced genome manipulation biotechnologies. Using evolutionary and biochemical analyses, we identify that the miniature type V-U4 nuclease (referred to as Cas12n, 400-700 amino acids) is likely the earliest evolutionary intermediate between TnpB and large type V CRISPR systems. We demonstrate that with the exception of CRISPR array emergence, CRISPR-Cas12n shares several similar characteristics with TnpB-ωRNA, including a miniature and likely monomeric nuclease for DNA targeting, origination of guide RNA from nuclease coding sequence, and generation of a small sticky end following DNA cleavage. Cas12n nucleases recognize a unique 5'-AAN PAM sequence, of which the A nucleotide at the -2 position is also required for TnpB. Moreover, we demonstrate the robust genome-editing capacity of Cas12n in bacteria and engineer a highly efficient CRISPR-Cas12n (termed Cas12Pro) with up to 80% indel efficiency in human cells. The engineered Cas12Pro enables base editing in human cells. Our results further expand the understanding regarding type V CRISPR evolutionary mechanisms and enrich the miniature CRISPR toolbox for therapeutic applications.


Subject(s)
CRISPR-Cas Systems , Gene Editing , Humans , CRISPR-Cas Systems/genetics , Gene Editing/methods , Endonucleases/genetics , DNA/genetics , RNA
2.
Nature ; 630(8016): 381-386, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38811733

ABSTRACT

Lignocellulose is mainly composed of hydrophobic lignin and hydrophilic polysaccharide polymers, contributing to an indispensable carbon resource for green biorefineries1,2. When chemically treated, lignin is compromised owing to detrimental intra- and intermolecular crosslinking that hampers downstream process3,4. The current valorization paradigms aim to avoid the formation of new C-C bonds, referred to as condensation, by blocking or stabilizing the vulnerable moieties of lignin5-7. Although there have been efforts to enhance biomass utilization through the incorporation of phenolic additives8,9, exploiting lignin's proclivity towards condensation remains unproven for valorizing both lignin and carbohydrates to high-value products. Here we leverage the proclivity by directing the C-C bond formation in a catalytic arylation pathway using lignin-derived phenols with high nucleophilicity. The selectively condensed lignin, isolated in near-quantitative yields while preserving its prominent cleavable ß-ether units, can be unlocked in a tandem catalytic process involving aryl migration and transfer hydrogenation. Lignin in wood is thereby converted to benign bisphenols (34-48 wt%) that represent performance-advantaged replacements for their fossil-based counterparts. Delignified pulp from cellulose and xylose from xylan are co-produced for textile fibres and renewable chemicals. This condensation-driven strategy represents a key advancement complementary to other promising monophenol-oriented approaches targeting valuable platform chemicals and materials, thereby contributing to holistic biomass valorization.


Subject(s)
Benzhydryl Compounds , Biomass , Chemical Fractionation , Lignin , Phenols , Benzhydryl Compounds/chemistry , Benzhydryl Compounds/metabolism , Catalysis , Cellulose/chemistry , Cellulose/metabolism , Chemical Fractionation/methods , Hydrogenation , Lignin/chemistry , Lignin/metabolism , Phenols/chemistry , Phenols/metabolism , Wood/chemistry , Xylans/chemistry , Xylans/metabolism , Xylose/chemistry , Xylose/metabolism , Fossil Fuels , Textiles
3.
Nature ; 616(7957): 482-487, 2023 04.
Article in English | MEDLINE | ID: mdl-37076728

ABSTRACT

Partitioning of americium from lanthanides (Ln) present in used nuclear fuel plays a key role in the sustainable development of nuclear energy1-3. This task is extremely challenging because thermodynamically stable Am(III) and Ln(III) ions have nearly identical ionic radii and coordination chemistry. Oxidization of Am(III) to Am(VI) produces AmO22+ ions distinct with Ln(III) ions, which has the potential to facilitate separations in principle. However, the rapid reduction of Am(VI) back to Am(III) by radiolysis products and organic reagents required for the traditional separation protocols including solvent and solid extractions hampers practical redox-based separations. Herein, we report a nanoscale polyoxometalate (POM) cluster with a vacancy site compatible with the selective coordination of hexavalent actinides (238U, 237Np, 242Pu and 243Am) over trivalent lanthanides in nitric acid media. To our knowledge, this cluster is the most stable Am(VI) species in aqueous media observed so far. Ultrafiltration-based separation of nanoscale Am(VI)-POM clusters from hydrated lanthanide ions by commercially available, fine-pored membranes enables the development of a once-through americium/lanthanide separation strategy that is highly efficient and rapid, does not involve any organic components and requires minimal energy input.

4.
Plant Cell ; 2024 May 03.
Article in English | MEDLINE | ID: mdl-38701330

ABSTRACT

Grain and flag leaf size are two important agronomic traits that influence grain yield in rice (Oryza sativa). Many QTLs and genes that regulate these traits individually have been identified, however, few QTLs and genes that simultaneously control these two traits have been identified. In this study, we conducted a genome-wide association analysis in rice and detected a major locus, WIDTH OF LEAF AND GRAIN (WLG), that associated with both grain and flag leaf width. WLG encodes a RING-domain E3 ubiquitin ligase. WLGhap.B, which possesses five SNP variations compared to WLGhap.A, encodes a protein with enhanced ubiquitination activity that confers increased rice leaf width and grain size, whereas mutation of WLG leads to narrower leaves and smaller grains. Both WLGhap.A and WLGhap.B interact with LARGE2, a HETC-type E3 ligase, however, WLGhap.B exhibits stronger interaction with LARGE2, thus higher ubiquitination activity towards LARGE2 compared with WLGhap.A. Lysine1021 is crucial for the ubiquitination of LARGE2 by WLG. Loss-of-function of LARGE2 in wlg-1 phenocopies large2-c in grain and leaf width, suggesting that WLG acts upstream of LARGE2. These findings reveal the genetic and molecular mechanism by which the WLG-LARGE2 module mediates grain and leaf size in rice, and suggest the potential of WLGhap.B in improving rice yield.

5.
Nat Chem Biol ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965385

ABSTRACT

Biochemical crosstalk between two or more histone modifications is often observed in epigenetic enzyme regulation, but its functional significance in cells has been difficult to discern. Previous enzymatic studies revealed that Lys14 acetylation of histone H3 can inhibit Lys4 demethylation by lysine-specific demethylase 1 (LSD1). In the present study, we engineered a mutant form of LSD1, Y391K, which renders the nucleosome demethylase activity of LSD1 insensitive to Lys14 acetylation. K562 cells with the Y391K LSD1 CRISPR knockin show decreased expression of a set of genes associated with cellular adhesion and myeloid leukocyte activation. Chromatin profiling revealed that the cis-regulatory regions of these silenced genes display a higher level of H3 Lys14 acetylation, and edited K562 cells show diminished H3 mono-methyl Lys4 near these silenced genes, consistent with a role for enhanced LSD1 demethylase activity. These findings illuminate the functional consequences of disconnecting histone modification crosstalk for a key epigenetic enzyme.

6.
Nucleic Acids Res ; 52(2): 967-976, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38096062

ABSTRACT

Pseudomonas aeruginosa harbors sophisticated transcription factor (TF) networks to coordinately regulate cellular metabolic states for rapidly adapting to changing environments. The extraordinary capacity in fine-tuning the metabolic states enables its success in tolerance to antibiotics and evading host immune defenses. However, the linkage among transcriptional regulation, metabolic states and antibiotic tolerance in P. aeruginosa remains largely unclear. By screening the P. aeruginosa TF mutant library constructed by CRISPR/Cas12k-guided transposase, we identify that rccR (PA5438) is a major genetic determinant in aminoglycoside antibiotic tolerance, the deletion of which substantially enhances bacterial tolerance. We further reveal the inhibitory roles of RccR in pyruvate metabolism (aceE/F) and glyoxylate shunt pathway (aceA and glcB), and overexpression of aceA or glcB enhances bacterial tolerance. Moreover, we identify that 2-keto-3-deoxy-6-phosphogluconate (KDPG) is a signal molecule that directly binds to RccR. Structural analysis of the RccR/KDPG complex reveals the detailed interactions. Substitution of the key residue R152, K270 or R277 with alanine abolishes KDPG sensing by RccR and impairs bacterial growth with glycerol or glucose as the sole carbon source. Collectively, our study unveils the connection between aminoglycoside antibiotic tolerance and RccR-mediated central carbon metabolism regulation in P. aeruginosa, and elucidates the KDPG-sensing mechanism by RccR.


Subject(s)
Bacterial Proteins , Carbon , Pseudomonas aeruginosa , Aminoglycosides/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Carbon/metabolism , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/metabolism , Bacterial Proteins/metabolism , Gene Regulatory Networks
7.
J Am Chem Soc ; 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38607333

ABSTRACT

Unraveling the mechanism of chirality transfer across length scales is crucial to the rational development of functional materials with hierarchical chirality. The key obstacle is the lack of structural information, especially at the mesoscopic level. We report herein the structural identification of helical covalent organic frameworks (heliCOFs) with hierarchical chirality, which integrate molecular chirality, channel chirality, and morphology chirality into one crystalline entity. Specifically, benefiting from the highly ordered structure of heliCOFs, the existence of chiral channels at the mesoscopic level has been confirmed by electron crystallography, and the handedness of these chiral channels has been directly determined through the stereopair imaging technique. Accordingly, the chirality transfer in heliCOFs from microscopic to macroscopic levels could be rationalized with a layer-rotating model that has been supported by both crystal structure analysis and theoretical calculations. Observation of chiral channels in heliCOFs not only provides unprecedented data for the understanding of the chirality transfer process but also sheds new light on the rational construction of highly ordered polymeric materials with hierarchical chirality.

8.
Mol Cancer ; 23(1): 132, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38926757

ABSTRACT

BACKGROUND: TFE3-rearranged renal cell carcinoma (TFE3-rRCC) is a rare but highly heterogeneous renal cell carcinoma (RCC) entity, of which the clinical treatment landscape is largely undefined. This study aims to evaluate and compare the efficacy of different systemic treatments and further explore the molecular correlates. METHODS: Thirty-eight patients with metastatic TFE3-rRCC were enrolled. Main outcomes included progression-free survival (PFS), overall survival, objective response rate (ORR) and disease control rate. RNA sequencing was performed on 32 tumors. RESULTS: Patients receiving first-line immune checkpoint inhibitor (ICI) based combination therapy achieved longer PFS than those treated without ICI (median PFS: 11.5 vs. 5.1 months, P = 0.098). After stratification of fusion partners, the superior efficacy of first-line ICI based combination therapy was predominantly observed in ASPSCR1-TFE3 rRCC (median PFS: not reached vs. 6.5 months, P = 0.01; ORR: 67.5% vs. 10.0%, P = 0.019), but almost not in non-ASPSCR1-TFE3 rRCC. Transcriptomic data revealed enrichment of ECM and collagen-related signaling in ASPSCR1-TFE3 rRCC, which might interfere with the potential efficacy of anti-angiogenic monotherapy. Whereas angiogenesis and immune activities were exclusively enriched in ASPSCR1-TFE3 rRCC and promised the better clinical outcomes with ICI plus tyrosine kinase inhibitor combination therapy. CONCLUSIONS: The current study represents the largest cohort comparing treatment outcomes and investigating molecular correlates of metastatic TFE3-rRCC based on fusion partner stratification. ICI based combination therapy could serve as an effective first-line treatment option for metastatic ASPSCR1-TFE3 rRCC patients. Regarding with other fusion subtypes, further investigations should be performed to explore the molecular mechanisms to propose pointed therapeutic strategy accordingly.


Subject(s)
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors , Carcinoma, Renal Cell , Immune Checkpoint Inhibitors , Kidney Neoplasms , Oncogene Proteins, Fusion , Humans , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Carcinoma, Renal Cell/drug therapy , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/mortality , Female , Male , Middle Aged , Kidney Neoplasms/drug therapy , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Kidney Neoplasms/mortality , Aged , Immune Checkpoint Inhibitors/therapeutic use , Oncogene Proteins, Fusion/genetics , Adult , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Gene Rearrangement , Biomarkers, Tumor/genetics , Treatment Outcome , Prognosis , Intracellular Signaling Peptides and Proteins/genetics
9.
Prostate ; 84(10): 932-944, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38629249

ABSTRACT

BACKGROUND: KI67 is a well-known biomarker reflecting cell proliferation. We aim to elucidate the predictive role of KI67 in the efficacy of abiraterone for patients with advanced prostate cancer (PCa). METHODS: Clinicopathological data of 152 men with metastatic PCa, who received abiraterone therapy were retrospectively collected. The KI67 positivity was examined by immunohistochemistry using the prostate biopsy specimen. The predictive value of KI67 on the therapeutic efficacy of abiraterone was explored using Kaplan-Meier curve and Cox regression analysis. The endpoints included prostate-specific antigen (PSA) progression-free survival (PSA-PFS), radiographic PFS (rPFS), and overall survival (OS). RESULTS: In total, 85/152 (55.9%) and 67/152 (44.1%) cases, respectively, received abiraterone at metastatic hormone-sensitive (mHSPC) and castration-resistant PCa (mCRPC) stage. The median KI67 positivity was 20% (interquartile range: 10%-30%). Overall, KI67 rate was not correlated with PSA response. Notably, an elevated KI67-positive rate strongly correlated with unfavorable abiraterone efficacy, with KI67 ≥ 30% and KI67 ≥ 20% identified as the optimal cutoffs for prognosis differentiation in mHSPC (median PSA-PFS: 11.43 Mo vs. 26.43 Mo, p < 0.001; median rPFS: 16.63 Mo vs. 31.90 Mo, p = 0.003; median OS: 21.77 Mo vs. not reach, p = 0.005) and mCRPC (median PSA-PFS: 7.17 Mo vs. 12.20 Mo, p = 0.029; median rPFS: 11.67 Mo vs. 16.47 Mo, p = 0.012; median OS: 21.67 Mo vs. not reach, p = 0.073) patients, respectively. Multivariate analysis supported the independent predictive value of KI67 on abiraterone efficacy. In subgroup analysis, an elevated KI67 expression was consistently associated with unfavorable outcomes in the majority of subgroups. Furthermore, data from another cohort of 79 PCa patients with RNA information showed that those with KI67 RNA levels above the median had a significantly shorter OS than those below the median (17.71 vs. 30.72 Mo, p = 0.035). CONCLUSIONS: This study highlights KI67 positivity in prostate biopsy as a strong predictor of abiraterone efficacy in advanced PCa. These insights will assist clinicians in anticipating clinical outcomes and refining treatment decisions for PCa patients.


Subject(s)
Androstenes , Biomarkers, Tumor , Ki-67 Antigen , Prostatic Neoplasms , Humans , Male , Ki-67 Antigen/analysis , Ki-67 Antigen/metabolism , Aged , Androstenes/therapeutic use , Retrospective Studies , Middle Aged , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Prostatic Neoplasms/metabolism , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/analysis , Cell Proliferation/drug effects , Prostate-Specific Antigen/blood , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/pathology , Prostatic Neoplasms, Castration-Resistant/metabolism , Treatment Outcome , Predictive Value of Tests , Progression-Free Survival , Aged, 80 and over , Antineoplastic Agents/therapeutic use
10.
Genome Res ; 31(1): 13-26, 2021 01.
Article in English | MEDLINE | ID: mdl-33328167

ABSTRACT

Long noncoding RNAs (lncRNAs) have emerged as diverse functional regulators involved in mammalian development; however, large-scale functional investigation of lncRNAs in mammalian spermatogenesis in vivo is lacking. Here, we delineated the global lncRNA expression landscape in mouse spermatogenesis and identified 968 germ cell signature lncRNAs. By combining bioinformatics and functional screening, we identified three functional lncRNAs (Gm4665, 1700027A15Rik, and 1700052I22Rik) that directly influence spermatogenesis in vivo. Knocking down Gm4665 hampered the development of round spermatids into elongating spermatids and disrupted key spermatogenic gene expression. Mechanistically, lncRNA Gm4665 localized in the nucleus of round spermatids and occupied the genomic regulatory region of important spermatogenic genes including Ip6k1 and Akap3 These findings provide a valuable resource and framework for future functional analysis of lncRNAs in spermatogenesis and their potential roles in other biological processes.


Subject(s)
Spermatogenesis , Animals , Gene Expression Profiling , Male , Mice , RNA, Long Noncoding/genetics , Spermatids , Spermatogenesis/genetics , Transcriptome
11.
Biol Reprod ; 110(5): 895-907, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38267362

ABSTRACT

It is known that the oocyte has a limited capacity to acquire and metabolize glucose, and it must rely on cumulus cells (CCs) to take up glucose and produce pyruvate for use to produce ATP through oxidative phosphorylation. We therefore propose that miRNAs might regulate glucose metabolism (GM) in CCs and might be used as markers for oocyte quality assessment. Here, mouse CC models with impaired glycolysis or pentose phosphate pathway (PPP) were established, and miRNAs targeting the key enzymes in glycolysis/PPP were predicted using the miRNA target prediction databases. Expression of the predicted miRNAs was compared between CCs with normal and impaired glycolysis/PPP to identify candidate miRNAs. Function of the candidate miRNAs was validated by transfecting CCs or cumulus-oocyte-complexes (COCs) with miRNA inhibitors and observing effects on glucose metabolites of CCs and on competence of oocytes. The results validated that miR-23b-3p, let-7b-5p, 34b-5p and 145a-5p inhibited glycolysis, and miR-24-3p, 3078-3p,183-5p and 7001-5p inhibited PPP of CCs. Our observation using a more physiologically relevant model (intact cultured COCs) further validated the four glycolysis-targeting miRNAs we identified. Furthermore, miR-let-7b-5p, 34b-5p and 145a-5p may also inhibit PPP, as they decreased the production of glucose-6-phosphate. In conclusion, miRNAs play critical roles in GM of CCs and may be used as markers for oocyte quality assessment. Summary sentence:  We identified and validated eight new miRNAs that inhibit glycolysis and/or pentose phosphate pathways in cumulus cells (CCs) suggesting that miRNAs play critical roles in glucose metabolism of CCs and may be used for oocyte quality markers.


Subject(s)
Cumulus Cells , Glucose , Glycolysis , MicroRNAs , Animals , Cumulus Cells/metabolism , MicroRNAs/metabolism , MicroRNAs/genetics , Mice , Glucose/metabolism , Female , Glycolysis/physiology , Pentose Phosphate Pathway , Oocytes/metabolism
12.
Chemistry ; 30(10): e202303476, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38065837

ABSTRACT

The construction of an all-in-one catalyst, in which the photosensitizer and the transition metal site are close to each other, is important for improving the efficiency of metallaphotoredox catalysis. However, the development of convenient synthetic strategies for the precise construction of an all-in-one catalyst remains a challenging task due to the requirement of precise installation of the catalytic sites. Herein, we have successfully established a facile bottom-up strategy for the direct synthesis of Ni(II)-incorporated covalent organic framework (COF), named LZU-713@Ni, as a versatile all-in-one metallaphotoredox catalyst. LZU-713@Ni showed excellent activity and recyclability in the photoredox/nickel-catalyzed C-O, C-S, and C-P cross-coupling reactions. Notably, this catalyst displayed a better catalytic activity than its homogeneous analogues, physically mixed dual catalyst system, and, especially, LZU-713/Ni which was prepared through post-synthetic modification. The improved catalytic efficiency of LZU-713@Ni should be attributed to the implementation of bottom-up strategy, which incorporated the fixed, ordered, and abundant catalytic sites into its framework. This work sheds new light on the exploration of concise and effective strategies for the construction of multifunctional COF-based photocatalysts.

13.
Inorg Chem ; 63(6): 2987-2996, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38295325

ABSTRACT

The current small-scale synthesis and relatively large size of Cu2O have limited its practical applications. Herein, we developed a hydrolysis strategy to prepare phase-pure Cu2O networks composed of small granules (ca. 25 nm) on a gram scale. The preparation involves in situ hydrolyzing the Hx[CuxCl2x] complexes prereduced in N,N'-dimethylformamide (DMF). The DMF-soluble Hx[CuxCl2x] complexes are critical for the homogeneous nucleation of CuCl seeds and subsequent hydrolysis, allowing for separate control over the nucleation and growth stages to regulate the formation of Cu2O networks. The novel Cu2O networks possess numerous exposed active sites and hierarchical porosities, conferring high catalytic activity and fast mass transfer capability. The inherent peroxidase-mimic activity of Cu2O is severely inhibited under neutral conditions but can be triggered by Cr6+, enabling the colorimetric assay of Cr6+ with the assistance of the oxidation-induced color change of 3,3',5,5'-tetramethylbenzidine. Through density functional theory calculation, we confirmed that the attachment of Cr6+ on the Cu2O surface reduced the dissociation energy of H2O2, enhancing the enzyme-mimic activity. The colorimetric detection method demonstrated a sensitive and specific assay capability for Cr6+ (LOD = 0.095 µM). Our work offers a straightforward protocol for novel design of metal or metal-based nanomaterials for nanozymes or other applications.

14.
Inorg Chem ; 63(1): 462-473, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38141022

ABSTRACT

Adding hydrophilic ligands into aqueous solutions for the selective binding of actinides(III) is acknowledged as an advanced strategy in Ln(III)/An(III) separation. In view of the recycling and radioactive waste disposal of the minor actinide, there remains an urgent need to design and develop the appropriate ligand for selective separation of An(III) from Ln(III). Herein, four novel hydrophilic ligands with hard-soft hybrid donors, derived from the pyridine and phenanthroline skeletons, were designed and synthesized as masking agents for selective complexation of An(III) in the aqueous phase. The known N,N,N',N'-tetraoctyl diglycolamide (TODGA) was used as lipophilic extractant in the organic phase for extraction of Ln(III), and a new strategy for the competitive extraction of An(III) and Ln(III) was developed based on TODGA and the above hydrophilic ligands. The optimal hydrophilic ligand of N,N'-bis(2-hydroxyethyl)-2,9-dicarboxamide-1,10-phenanthroline (2OH-DAPhen) displayed exceptional selectivity toward Am(III) over Ln(III), with the concentrations of HNO3 ranging from 0.05 to 3.0 M. The maximum separation factors were up to 1365 for Eu/Am, 417.66 for Eu/Cm, and 42.38 for La/Am. The coordination mode and bonding property of 2OH-DAPhen with Ln(III) were investigated by 1H NMR titration, UV-vis spectrophotometric titration, luminescence titration, FT-IR, ESI-HRMS analysis, and DFT calculations. The results revealed that the predominant species formed in the aqueous phase was a 1:1 ligand/metal complex. DFT calculations also confirmed that the affinity of 2OH-DAPhen for Am(III) was better than that for Eu(III). The present work using a competitive extraction strategy developed a feasible alternative method for the selective separation of trivalent actinides from lanthanides.

15.
Nanotechnology ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38955169

ABSTRACT

Combining the photoisomerization of molecules with an electrical device is important for developing optoelectronic devices. Field effect transistors (FETs) with atomically thin channels are suitable for this purpose because the FET properties respond to chemical changes in molecules. Since the photoisomerization wavelength of the switching molecules can be tuned, complex logic operations can be realized if a specific molecule is delivered to the target FET of an integrated circuit. However, conventional techniques for transferring molecules, such as drop casting and sublimation, cannot efficiently realize this goal. In this study, we fabricated a MoS2 FET device combined with a microfluidic platform, wherein the MoS2 channel was in contact with the flow of an azobenzene solution in isopropyl alcohol as the solvent. UV radiation (365 nm) and thermal relaxation realize the cycle of trans- and cis-azobenzene states and the switching of the substantial FET properties. This study demonstrated the feasibility of using the solution for optical switching of the MoS2-FET, which can realize quick phase changes in the molecule and the delivery of the molecule to the target FET by a microfluidic platform. .

16.
Anal Bioanal Chem ; 416(2): 363-372, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37935845

ABSTRACT

A recent outbreak of porcine circovirus-like virus (PCLV), a virus that may be associated with porcine diarrhea, has been reported in swine herds in China. The virus is spreading rapidly, causing huge economic losses to the swine farming industry. To achieve the rapid, inexpensive, and sensitive detection of PCLV, we combined loop-mediated isothermal amplification (LAMP) and the CRISPR/Cas12a system, whose fluorescence intensity readout can detect PCLV ORF4 gene levels as low as 10 copies. To overcome the need for sophisticated equipment, lateral flow strip reading technology was introduced for the first time in a LAMP-Cas12a-based system to detect PCLV. The lateral flow strip (LFS) results were readout by the naked eye, and the method was highly sensitive with a detection limit of 10 copies, with a detection time of about 60 min. In addition, the method is highly specific and has no cross-reactivity with other related viruses. In conclusion, LAMP-CRISPR/Cas12a-based assays have the advantages of rapidity, accuracy, portability, low cost, and visualization of the results. They therefore have great potential, especially for areas where specialized equipment is lacking, and can expect to be an ideal method for early diagnosis and on-site detection of PCLV.


Subject(s)
Circovirus , Swine Diseases , Viruses , Swine , Animals , Circovirus/genetics , CRISPR-Cas Systems , Swine Diseases/diagnosis , Sensitivity and Specificity , Nucleic Acid Amplification Techniques/methods
17.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 225-232, 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38650129

ABSTRACT

Abnormal expression of non-coding microRNA is associated with the development of combined allergic rhinitis and asthma syndrome (CARAS). However, the function of miR-4454 in CARAS is unknown. Our study aimed to reveal the clinical significance and related mechanism of miR-4454 in CARAS. Blood samples from 38 cases of CARAS and 43 cases of healthy subjects were collected to detect the expression of miR-4454. House dust mite (HDM) sensitization and challenge-induced bronchial epithelial cells to simulate the asthma state model in vitro, miR-4454 mimics and inhibitor transfection to detect the expression level of pro-inflammatory cytokines, cell survival rate and migration ability, flow cytometry and western blot (WB) Detection of cell cycle, apoptosis and inflammation-related protein levels. Compared with healthy controls, the expression of miR-4454 in the blood of CARAS patients was significantly up-regulated, and IL-6 and IL-8 were significantly up-regulated in the HDM treatment group, indicating that the model induction was successful. After overexpression of miR-4454, cell proliferation and migration in the HDM-treated group were significantly inhibited, and the levels of early apoptosis and inflammation-related proteins (IL-17, IL-17RD, TNF-α, GCSF and NF-κB) were increased High; after inhibiting miR-4454, cell proliferation and migration were significantly enhanced, and the levels of apoptosis and inflammation-related proteins were decreased. This study found that inhibiting the expression of miR-4454 can improve HDM-induced cell injury, which may be related to miR-4454 regulating the activation of IL-17/NF-кB inflammatory axis.


Subject(s)
Apoptosis , Asthma , Cell Proliferation , MicroRNAs , Rhinitis, Allergic , MicroRNAs/genetics , MicroRNAs/metabolism , Humans , Rhinitis, Allergic/genetics , Rhinitis, Allergic/metabolism , Asthma/genetics , Asthma/pathology , Male , Female , Apoptosis/genetics , Adult , Cell Proliferation/genetics , Animals , Inflammation/genetics , Inflammation/pathology , Cell Movement/genetics , Pyroglyphidae/immunology , Cytokines/metabolism , Cytokines/blood , NF-kappa B/metabolism , Case-Control Studies , Epithelial Cells/metabolism , Syndrome , Clinical Relevance
18.
Eur J Clin Pharmacol ; 80(6): 827-838, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38483545

ABSTRACT

INTRODUCTION: Since the first experimentally proven tyrosine kinase inhibitor (TKI) imatinib was introduced in the clinical setting, TKIs have attracted widespread attention because of their remarkable therapeutic effects and improvement of survival rates. TKIs are small-molecule, multi-target, anti-cancer agents that target different tyrosine kinases and block downstream signaling. ADVERSE REACTIONS AND CONCERNS: However, with in-depth research on TKI drugs, the adverse reactions-for example, thyroid dysfunction-have become a concern and thus have attracted the attention of numerous researchers. Thyroid dysfunction, especially hypothyroidism, that occurs in high incidence during TKI therapy has a close relationship with treatment efficacy, but the mechanism of TKI-induced thyroid dysfunction is obscure. DISCUSSION: This review discusses the epidemiology, possible mechanisms, and clinical significance of hypothyroidism in cancer patients treated with TKI.


Subject(s)
Antineoplastic Agents , Hypothyroidism , Protein Kinase Inhibitors , Humans , Hypothyroidism/chemically induced , Protein Kinase Inhibitors/adverse effects , Antineoplastic Agents/adverse effects , Protein-Tyrosine Kinases/antagonists & inhibitors , Neoplasms/drug therapy , Animals
19.
Appl Opt ; 63(12): 3015-3028, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38856445

ABSTRACT

The accuracy of the absolute radiometric calibration (RadCal) for remote sensing instruments is essential to their wide range of applications. The uncertainty associated with the traditional source-based RadCal method is assessed at a 2% (k=1) or higher level for radiance measurement. To further improve the accuracy to meet the demands of climate studies, a detector-based approach using tunable lasers as a light source has been devised. The Goddard Laser for Absolute Measurement of Radiance, known as the GLAMR system, is a notable example of the incorporation of such technology. Using transfer radiometers calibrated at the National Institute of Standards and Technology as calibration standards, the absolute spectral response function of a remote sensing instrument is measured with its uncertainty traceable to the International System of Units. This paper presents a comprehensive uncertainty analysis of the detector-based absolute RadCal using the GLAMR system. It identifies and examines uncertainty sources during the GLAMR RadCal test, including those from the GLAMR system, the testing configuration, and data processing methodologies. Analysis is carried out to quantify the contribution of each source and emphasize the most influential factors. It is shown that the calibration uncertainty of GLAMR RadCal can be better than 0.3% (k=1) in the wavelength range of 350-950 nm and 0.6% (k=1) between 950 and 2300 nm, with the exception of regions with strong water absorption. In addition, recommendations are made to refine the calibration process to further reduce the uncertainty.

20.
Biotechnol Lett ; 46(4): 531-543, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38607604

ABSTRACT

Biofuel production from lignocellulose feedstocks is sustainable and environmentally friendly. However, the lignocellulosic pretreatment could produce fermentation inhibitors causing multiple stresses and low yield. Therefore, the engineering construction of highly resistant microorganisms is greatly significant. In this study, a composite functional chimeric cellulosome equipped with laccase, versatile peroxidase, and lytic polysaccharide monooxygenase was riveted on the surface of Saccharomyces cerevisiae to construct a novel yeast strain YI/LVP for synergistic lignin degradation and cellulosic ethanol production. The assembly of cellulosome was assayed by immunofluorescence microscopy and flow cytometry. During the whole process of fermentation, the maximum ethanol concentration and cellulose conversion of engineering strain YI/LVP reached 8.68 g/L and 83.41%, respectively. The results proved the availability of artificial chimeric cellulosome containing lignin-degradation enzymes for cellulosic ethanol production. The purpose of the study was to improve the inhibitor tolerance and fermentation performance of S. cerevisiae through the construction and optimization of a synergistic lignin-degrading enzyme system based on cellulosome.


Subject(s)
Cellulosomes , Ethanol , Fermentation , Lignin , Saccharomyces cerevisiae , Ethanol/metabolism , Lignin/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/enzymology , Cellulosomes/metabolism , Cellulosomes/genetics , Cellulose/metabolism , Laccase/metabolism , Laccase/genetics
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