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1.
Proc Natl Acad Sci U S A ; 120(18): e2219034120, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094158

RESUMO

Escape from metastable states in self-assembly of colloids is an intractable problem. Unlike the commonly adopted approach of thermal annealing, the recently developed enthalpy-mediated strategy provided a different option to address this dilemma in a dynamically controllable manner at room temperature. However, it required a complex catalytic-assembly DNA strand-displacement circuitry to mediate interaction between multiple components. In this work, we present a simple but effective way to achieve catalytic-assembly of DNA-functionalized colloidal nanoparticles, i.e., programmable atom equivalents, in a far-from-equilibrium system. A removable molecule named "catassembler" that acts as a catalyst was employed to rectify imperfect linkages and help the system escape from metastability without affecting the assembled framework. Notably, catalytic efficiency of the catassembler can be effectively improved by changing the seesaw catassembler in toehold length design or numbers of the repeat units. Leveraging this tractable catalytic-assembly approach, different ordered architectures were easily produced by directly mixing all reactants, as in chemical reactions. By switching bonding identities, solid-solid phase transformations between different colloidal crystals were achieved. This work opens up an avenue for programming colloid assembly in a far-from-equilibrium system.

2.
Proc Natl Acad Sci U S A ; 120(22): e2221127120, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216515

RESUMO

CRISPR/Cas9 genome-editing tools have tremendously boosted our capability of manipulating the eukaryotic genomes in biomedical research and innovative biotechnologies. However, the current approaches that allow precise integration of gene-sized large DNA fragments generally suffer from low efficiency and high cost. Herein, we developed a versatile and efficient approach, termed LOCK (Long dsDNA with 3'-Overhangs mediated CRISPR Knock-in), by utilizing specially designed 3'-overhang double-stranded DNA (odsDNA) donors harboring 50-nt homology arm. The length of the 3'-overhangs of odsDNA is specified by the five consecutive phosphorothioate modifications. Compared with existing methods, LOCK allows highly efficient targeted insertion of kilobase-sized DNA fragments into the mammalian genomes with low cost and low off-target effects, yielding >fivefold higher knock-in frequencies than conventional homologous recombination-based approaches. This newly designed LOCK approach based on homology-directed repair is a powerful tool suitable for gene-sized fragment integration that is urgently needed for genetic engineering, gene therapies, and synthetic biology.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Animais , Sistemas CRISPR-Cas/genética , Sequência de Bases , Edição de Genes/métodos , DNA/genética , Recombinação Homóloga , Mamíferos/genética
3.
J Am Chem Soc ; 144(28): 12690-12697, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35792375

RESUMO

Multi-module dCas9 engineering systems have been developed for controllable transcriptional manipulation such as chemical- or light-induced systems. However, there is still a need for a separate module that can be used for internal control over the CRISPR-dCas9 system. Here, we describe a multi-module CRISPR-dCas9 system in which a separate structured RNA was applied as a programmable component that could control dCas9-based gene regulation and achieved a higher activation efficiency than dCas9-VPR that is traditionally used. By introducing a microRNA sensor, we generated a dCas9-based transcriptional regulation platform that responded to endogenous microRNAs and allowed controllable activation of endogenous genes. Moreover, we applied the platform to selectively identify HCT116 cells in a cell mixture. This work provides a flexible platform for efficient and controllable gene regulation based on CRISPR-dCas9.


Assuntos
Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Sistemas CRISPR-Cas/genética , RNA/genética , Ativação Transcricional
4.
Materials (Basel) ; 17(18)2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39336348

RESUMO

Laser metal deposition is a promising way to repair the surface defects of single-crystal components in turbo engines. Understanding the mechanisms and improving the efficiency of the repair have been long-standing problems. In this study, the influence of the substrate orientation on the laser metal deposition (LMD) was investigated and its effect on repair layer-step was examined. LMD experiments were conducted on single crystal superalloys with a normal substrate orientation (001)/[100] and with an optimized substrate orientation (101)/[101¯]. It reveals that the laser cladding with the optimized orientation leads to a larger height of the [001] dendrite region than that with the normal orientation. The calculated results of the growth velocity, thermal gradient, and susceptibility to CET in the dendrite-preferred growth direction indicate that, for the (101)/[101¯] orientation, the [001]/[100] boundary is located at relative high position in each layer, which not only decreases the formation ability of stray grain significantly, but also eliminates the appearance of the maximum susceptibility. This makes the necessary dilution position much higher, and thus, a large cladding step can be selected. Our findings could find potential applications in laser repair of single-crystal components.

5.
Insects ; 15(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38667357

RESUMO

The pest management of Plutella xylostella, the global pest of cruciferous plants, is primarily dependent upon continued applications of insecticides, which has led to severe insecticide resistance and a series of ecological concerns. The essential oils (EOs) of non-host plants are considered to have a high application potential in pest behavioral control. In P. xylostella, the insecticidal properties, antifeeding activities, and oviposition inhibition effects of many EOs have been studied in larvae and female moths. However, less focus has been placed on the inhibitory effect on sex pheromone communication during courtship, which is vital for the reproduction of the offspring. In this study, by combining electrophysiological studies, laboratory behavioral assays, and field traps, we demonstrated that non-host plant EOs significantly inhibited the reproductive behaviors of both sexes. Notably, the calamus (Acorus gramineus) EO inhibited the preference of male moths for synthetic sex pheromone blends and reduced the egg-laying number of female moths on host plants, with the highest inhibition rates of 72% and 100%, respectively, suggesting a great application prospect of calamus and its EO on the behavioral control strategies of P. xylostella.

6.
Risk Manag Healthc Policy ; 17: 1069-1078, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699655

RESUMO

Objective: We investigated the clinical characteristics, fall outcomes, and related factors of falls in patients who were hospitalized in the rehabilitation department, and explored strategies to reduce the incidence of falls and prevent falls in patients. Methods: Data from 60 patients who fell in the rehabilitation department between 2016 and 2021 were analyzed for clinical characteristics, associated factors, incidence of falls, injuries, and patient demographics. Under the random stratified sampling method, 60 patients who did not fall during the same period were selected as the control group, and relevant data was collected. Measurement data were compared using an independent sample t-test. Enumeration data were compared using chi-squared (χ2) test was employed to compare these data between the two groups. Non-parametric data were analyzed using the Mann-Whitney U-test. Factors potentially influencing falls were scrutinized through both univariate and binary logistic regression analyses. Results: The median annual incidence of falls among patients who were hospitalized in the rehabilitation department was 0.04%, while the overall fall injury rate was 60%. Falls were most prevalent within 30 days of hospitalization (71.67%). The most common fall-related condition was craniocerebral disease (83.33%). The incidents of falls location of fall were mainly reported in nearby areas of rehabilitation ward (70%). Most accidents occurred between 7:00 a.m.-12:00 p.m. and 3:01 p.m.-6:00 p.m. (63.33%), and dyskinesia was the most common cause of falls (71.67%). There were 39 patients (65.00%) with Barthel Index (BI) scores ranging between 40-60. Conclusion: Patients in the rehabilitation department had a greater incidence of falls and fall injuries. Within 30 days of admission, patients with moderately dependent craniocerebral disorders and dyskinesia frequently experienced falls during typical daytime shifts in areas characterized by endemic conditions.

7.
Dalton Trans ; 52(11): 3526-3536, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36847189

RESUMO

Ternary transition metal oxides (TMOs) are potentially promising anode materials for lithium storage with high power and energy density. Designing appropriate electrode structures is an effective strategy to sufficiently exhibit the advantages of TMOs for lithium storage. Here, we present the synthetic process and electrochemical properties of carbon-coated mesoporous Ni-Mn-Co-O (NMCO) nanowire arrays (NWAs) grown on Ni foam as an integrated electrode for lithium-ion batteries (LIBs). The electrochemical measurements show that the carbon-coated NMCO integrated electrode exhibits high capacity and cycling properties. In addition, we have also developed an all one-dimensional (1D) structural full cell using an LiMn2O4 nanorod cathode and an NMCO/Ni NWAs@C-550 anode, which exhibits relatively outstanding cycling properties.

8.
Dalton Trans ; 52(17): 5804-5805, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37092775

RESUMO

Correction for 'Mesoporous polyvalent Ni-Mn-Co-O composite nanowire arrays towards integrated anodes boosting high-properties lithium storage' by Junxiang Zhou et al., Dalton Trans., 2023, 52, 3526-3536, https://doi.org/10.1039/D3DT00211J.

9.
ACS Chem Biol ; 18(5): 1246-1253, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37105947

RESUMO

Nuclear localization signal (NLS) is a short peptide guiding the nuclear transport process, recognized as playing an important role in constructing clustered regularly interspaced short palindromic repeats-Cas (CRISPR-Cas) activators. Here, we investigate the effect of the position and number of the NLS on transcriptional activation based on the dCas9-VPR activator. Our results not only demonstrate that the position of the SV40 NLS could have different degrees of influence on activation efficiency but also, surprisingly, we find that the SV40 NLS plays a detrimental role. Complete deletion of the NLS from the system could increase the transcriptional activation efficiency by 2 to 4 times compared with the original dCas9-VPR. This finding is also supported by some typical first- and third-generation activators. Our work should be beneficial to the design of the NLS-based system.


Assuntos
Sistemas CRISPR-Cas , Sinais de Localização Nuclear , Ativação Transcricional , Transporte Biológico , Núcleo Celular
10.
Dalton Trans ; 51(48): 18622-18632, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36448337

RESUMO

Multi-component nano-oxide composite materials may present special synergistic effects as anode materials for lithium-ion batteries. Mesoporous ß-MnO2/Mn3O4 composite nanotubes are built here via controlling the deoxidation process of carbon-coating to induce a partial phase transition of high valence manganese dioxides. Compared to single ß-MnO2 nanotubes or Mn3O4@C nanotubes, the mesoporous ß-MnO2/Mn3O4@C composite nanotubes exhibit superior electrochemical properties. 679 mA h g-1 of reversible specific capacity and 86% of capacity retention after 1000 cycles at 1 A g-1 current density are obtained. The excellent performance is attributed to the unique multiple phase transitions regulation phenomena of manganese oxide occurring in the ß-MnO2/Mn3O4 composite material during the electrochemical processes, which significantly extends the cycle life of the ß-MnO2/Mn3O4 composite material.

11.
J Mater Chem B ; 10(26): 4959-4966, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35730726

RESUMO

The emergence of synthetic biology has opened new avenues in constructing cell-assembly biosystems with specific gene expression and function. The phenomena of cell spreading and detachment during tissue development and cancer metastasis are caused by surface tension, which in turn results from differences in cell-cell adhesion mediated by the dimerization of cadherin expressed on the cell surface. In this study, E- and P-cadherin plasmids were first constructed based on the differential adhesion hypothesis, then they were electroporated into K562 cells and HEK293T cells, respectively, to explore the process of cell migration and assembly regulated by cadherins. Using this approach, some special 3D cell functional components with a phase separation structure were fabricated successfully. Our work will be of potential application in the construction of self-assembling synthetic tissues and organoids.


Assuntos
Caderinas , Antígenos CD/fisiologia , Caderinas/metabolismo , Caderinas/fisiologia , Adesão Celular/fisiologia , Membrana Celular/metabolismo , Movimento Celular/fisiologia , Células HEK293 , Humanos , Células K562 , Plasmídeos
12.
Nat Cell Biol ; 24(4): 526-537, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418624

RESUMO

D-2-Hydroxyglutarate (D-2HG) is an α-ketoglutarate-derived mitochondrial metabolite that causes D-2-hydroxyglutaric aciduria, a devastating developmental disorder. How D-2HG adversely affects mitochondria is largely unknown. Here, we report that in Caenorhabditis elegans, loss of the D-2HG dehydrogenase DHGD-1 causes D-2HG accumulation and mitochondrial damage. The excess D-2HG leads to a build-up of 3-hydroxypropionate (3-HP), a toxic metabolite in mitochondrial propionate oxidation, by inhibiting the 3-HP dehydrogenase HPHD-1. We demonstrate that 3-HP binds the MICOS subunit MIC60 (encoded by immt-1) and inhibits its membrane-binding and membrane-shaping activities. We further reveal that dietary and gut bacteria affect mitochondrial health by modulating the host production of 3-HP. These findings identify a feedback loop that links the toxic effects of D-2HG and 3-HP on mitochondria, thus providing important mechanistic insights into human diseases related to D-2HG and 3-HP.


Assuntos
Encefalopatias Metabólicas Congênitas , Propionatos , Encefalopatias Metabólicas Congênitas/metabolismo , Retroalimentação , Glutaratos/metabolismo , Humanos , Isocitrato Desidrogenase/metabolismo , Mitocôndrias/metabolismo , Oxirredutases , Propionatos/metabolismo
13.
PLoS One ; 15(4): e0231763, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302346

RESUMO

OBJECTIVE: To evaluate the efficacy, safety and cost-effectiveness of Oxycodone Hydrochloride Controlled-release Tablets (CR oxycodone) and Morphine Sulfate Sustained-release Tablets (SR morphine) for moderate to severe cancer pain titration. METHODS: Randomized controlled trials meeting the inclusion criteria were searched through Medline, Cochrane Library, Pubmed, EMbase, CNKI,VIP and WanFang database from the data of their establishment to June 2019. The efficacy and safety data were extracted from the included literature. The pain control rate was calculated to eatimate efficacy. Meta-analysis was conducted by Revman5.1.4. A decision tree model was built to simulate cancer pain titration process. The initial dose of CR oxycodone and SR morphine group were 20mg and 30mg respectively. Oral immediate-release morphine was administered to treat break-out pain. The incremental cost-effectiveness ratio was performed with TreeAge Pro 2019. RESULTS: 19 studies (1680 patients)were included in this study. Meta-analysis showed that the pain control rate of CR oxycodone and SR morphine were 86% and 82.98% respectively. The costs of CR oxycodone and SR morphine were $23.27 and $13.31. The incremental cost-effectiveness ratio per unit was approximate $329.76. At the willingness-to-pay threshold of $8836, CR oxycodone was cost-effective, while the corresponding probability of being cost-effective at the willingness-to-pay threshold of $300 was 31.6%. One-way sensitivity analysis confirmed robustness of results. CONCLUSIONS: CR oxycodone could be a cost-effective option compared with SR morphine for moderate to severe cancer pain titration in China, according to the threshold defined by the WHO.


Assuntos
Dor do Câncer/tratamento farmacológico , Dor do Câncer/economia , Farmacoeconomia , Morfina/economia , Morfina/uso terapêutico , Oxicodona/economia , Oxicodona/uso terapêutico , Análise Custo-Benefício , Árvores de Decisões , Preparações de Ação Retardada/uso terapêutico , Humanos , Viés de Publicação , Risco , Resultado do Tratamento
14.
J Genet Genomics ; 47(3): 145-156, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32305173

RESUMO

Arginine catabolism involves enzyme-dependent reactions in both mitochondria and the cytosol, defects in which may lead to hyperargininemia, a devastating developmental disorder. It is largely unknown if defective arginine catabolism has any effects on mitochondria. Here we report that normal arginine catabolism is essential for mitochondrial homeostasis in Caenorhabditiselegans. Mutations of the arginase gene argn-1 lead to abnormal mitochondrial enlargement and reduced adenosine triphosphate (ATP) production in C. elegans hypodermal cells. ARGN-1 localizes to mitochondria and its loss causes arginine accumulation, which disrupts mitochondrial dynamics. Heterologous expression of human ARG1 or ARG2 rescued the mitochondrial defects of argn-1 mutants. Importantly, genetic inactivation of the mitochondrial basic amino acid transporter SLC-25A29 or the mitochondrial glutamate transporter SLC-25A18.1 fully suppressed the mitochondrial defects caused by argn-1 mutations. These findings suggest that mitochondrial damage probably contributes to the pathogenesis of hyperargininemia and provide clues for developing therapeutic treatments for hyperargininemia.


Assuntos
Arginase/genética , Arginina/metabolismo , Mitocôndrias/genética , Trifosfato de Adenosina/genética , Animais , Arginina/genética , Caenorhabditis elegans/genética , Citosol/enzimologia , Modelos Animais de Doenças , Homeostase/genética , Humanos , Hiperargininemia/genética , Hiperargininemia/metabolismo , Mutação
15.
Dalton Trans ; 48(8): 2741-2749, 2019 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-30724296

RESUMO

Electrochemical performances of lithium-ion batteries depend strongly on the micro-nanostructures of active materials as well as electrode configurations. A reasonable design of both active materials and electrode configuration is of great importance to improving the electrochemical properties of the batteries. Here, we present the preparation and electrochemical properties of mesoporous Ni-Mn-Co-O oxide (NMCO) nanowire arrays (NWAs) directly grown on Cu substrates, which can be used as an integrated electrode for lithium-ion batteries. The electrochemical measurements show that the NMCO/Cu NWA integrated electrodes without binder exhibit enhanced cycling stability and high specific capacity compared with the NMCO nanowire electrode prepared by a conventional coating process. In addition, the NMCO/Cu-foam NWA integrated electrode constructed from porous copper exhibits outstanding cycle stability and rate capability compared with the NMCO/Cu-foil NWA integrated electrode based on a copper foil collector.

16.
Chem Commun (Camb) ; 55(77): 11615-11618, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501837

RESUMO

To date, implementation of renewable DNA circuits remains challenging due to issues including reactant depletion and waste accumulation. Herein we simultaneously addressed both issues through nicking enzyme-assisted waste-to-reactant transformation. As a proof-of-concept, a renewable entropy-driven catalytic DNA circuit was implemented, exhibiting a good renewability when replenishing fuel.


Assuntos
DNA Catalítico/química , Endonucleases/química , Redes Reguladoras de Genes , Pareamento Incorreto de Bases , Catálise , Entropia , Corantes Fluorescentes/química , Cinética , Conformação de Ácido Nucleico , Estudo de Prova de Conceito , Espectrometria de Fluorescência
17.
J Cell Biol ; 218(8): 2619-2637, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31235480

RESUMO

Phagocytic removal of apoptotic cells involves formation, maturation, and digestion of cell corpse-containing phagosomes. The retrieval of lysosomal components following phagolysosomal digestion of cell corpses remains poorly understood. Here we reveal that the amino acid transporter SLC-36.1 is essential for lysosome reformation during cell corpse clearance in Caenorhabditis elegans embryos. Loss of slc-36.1 leads to formation of phagolysosomal vacuoles arising from cell corpse-containing phagosomes. In the absence of slc-36.1, phagosome maturation is not affected, but the retrieval of lysosomal components is inhibited. Moreover, loss of PPK-3, the C. elegans homologue of the PtdIns3P 5-kinase PIKfyve, similarly causes accumulation of phagolysosomal vacuoles that are defective in phagocytic lysosome reformation. SLC-36.1 and PPK-3 function in the same genetic pathway, and they directly interact with one another. In addition, loss of slc-36.1 and ppk-3 causes strong defects in autophagic lysosome reformation in adult animals. Our findings thus suggest that the PPK-3-SLC-36.1 axis plays a central role in both phagocytic and autophagic lysosome formation.


Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Caenorhabditis elegans/metabolismo , Lisossomos/metabolismo , Fagocitose , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas Carreadoras de Solutos/metabolismo , Animais , Apoptose , Autofagia , Caenorhabditis elegans/ultraestrutura , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Lisossomos/ultraestrutura , Fagossomos/metabolismo , Fagossomos/ultraestrutura , Vacúolos/metabolismo , Vacúolos/ultraestrutura
18.
J Cell Biol ; 218(2): 580-597, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30573525

RESUMO

Amino acid catabolism is frequently executed in mitochondria; however, it is largely unknown how aberrant amino acid metabolism affects mitochondria. Here we report the requirement for mitochondrial saccharopine degradation in mitochondrial homeostasis and animal development. In Caenorhbditis elegans, mutations in the saccharopine dehydrogenase (SDH) domain of the bi-functional enzyme α-aminoadipic semialdehyde synthase AASS-1 greatly elevate the lysine catabolic intermediate saccharopine, which causes mitochondrial damage by disrupting mitochondrial dynamics, leading to reduced adult animal growth. In mice, failure of mitochondrial saccharopine oxidation causes lethal mitochondrial damage in the liver, leading to postnatal developmental retardation and death. Importantly, genetic inactivation of genes that raise the mitochondrial saccharopine precursors lysine and α-ketoglutarate strongly suppresses SDH mutation-induced saccharopine accumulation and mitochondrial abnormalities in C. elegans Thus, adequate saccharopine catabolism is essential for mitochondrial homeostasis. Our study provides mechanistic and therapeutic insights for understanding and treating hyperlysinemia II (saccharopinuria), an aminoacidopathy with severe developmental defects.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Homeostase , Lisina/análogos & derivados , Mitocôndrias Hepáticas , Sacaropina Desidrogenases , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Hiperlisinemias/genética , Hiperlisinemias/metabolismo , Lisina/metabolismo , Camundongos , Mitocôndrias Hepáticas/genética , Mitocôndrias Hepáticas/metabolismo , Mutação , Sacaropina Desidrogenases/deficiência , Sacaropina Desidrogenases/genética , Sacaropina Desidrogenases/metabolismo
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