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1.
Chemistry ; : e202401826, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747420

RESUMO

Reaction of a rare and well-characterized MnIII-superoxo species, Mn(BDPBrP)(O2•) (1, H2BDPBrP = 2,6-bis((2-(S)-di(4-bromo)phenylhydroxylmethyl-1-pyrrolidinyl)methyl)pyridine), with 4-dimethylaminophenol at -80 °C proceeds via concerted proton electron transfer (CPET) to produce a MnIII-hydroperoxo complex, Mn(BDPBrP)(OOH) (2), alongside 4-dimethylaminophenoxy radical; whereas, upon treatment with 4-nitrophenol, complex 1 undergoes a proton transfer process to afford a MnIV-hydroperoxo complex, [Mn(BDPBrP)(OOH)]+ (3). Intriguingly, the reactions of 1 with 4-chlorophenol and 4-methoxyphenol follow two routes of CPET and sequential proton and electron transfer to furnish complex 2 in the end. UV-vis and EPR spectroscopic studies coupled with DFT calculations provided support for this wide mechanistic spectrum of activating various phenol O-H bonds by a single MnIII-superoxo complex, 1.

2.
Adv Mater ; : e2401482, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695389

RESUMO

Lithium-ion batteries (LIBs), in which lithium ions function as charge carriers, are considered the most competitive energy storage devices due to their high energy and power density. However, battery materials, especially with high capacity undergo side reactions and changes that result in capacity decay and safety issues. A deep understanding of the reactions that cause changes in the battery's internal components and the mechanisms of those reactions is needed to build safer and better batteries. This review focuses on the processes of battery failures, with voltage and temperature as the underlying factors. Voltage-induced failures result from anode interfacial reactions, current collector corrosion, cathode interfacial reactions, overcharge, and overdischarge, while temperature-induced failure mechanisms include SEI decomposition, separator damage, and interfacial reactions between electrodes and electrolytes. The review also presents protective strategies for controlling these reactions. As a result, the reader is offered a comprehensive overview of the safety features and failure mechanisms of various LIB components. This article is protected by copyright. All rights reserved.

3.
Acta Pharmacol Sin ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740904

RESUMO

The circadian clock is the inner rhythm of life activities and is controlled by a self-sustained and endogenous molecular clock, which maintains a ~ 24 h internal oscillation. As the core element of the circadian clock, BMAL1 is susceptible to degradation through the ubiquitin-proteasome system (UPS). Nevertheless, scant information is available regarding the UPS enzymes that intricately modulate both the stability and transcriptional activity of BMAL1, affecting the cellular circadian rhythm. In this work, we identify and validate UBR5 as a new E3 ubiquitin ligase that interacts with BMAL1 by using affinity purification, mass spectrometry, and biochemical experiments. UBR5 overexpression induced BMAL1 ubiquitination, leading to diminished stability and reduced protein level of BMAL1, thereby attenuating its transcriptional activity. Consistent with this, UBR5 knockdown increases the BMAL1 protein. Domain mapping discloses that the C-terminus of BMAL1 interacts with the N-terminal domains of UBR5. Similarly, cell-line-based experiments discover that HYD, the UBR5 homolog in Drosophila, could interact with and downregulate CYCLE, the BMAL1 homolog in Drosophila. PER2-luciferase bioluminescence real-time reporting assay in a mammalian cell line and behavioral experiments in Drosophila reveal that UBR5 or hyd knockdown significantly reduces the period of the circadian clock. Therefore, our work discovers a new ubiquitin ligase UBR5 that regulates BMAL1 stability and circadian rhythm and elucidates the underlying molecular mechanism. This work provides an additional layer of complexity to the regulatory network of the circadian clock at the post-translational modification, offering potential insights into the modulation of the dysregulated circadian rhythm.

4.
J Bone Joint Surg Am ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662805

RESUMO

BACKGROUND: Recent evidence showing that computer-assisted total knee arthroplasty (TKA) is associated with better outcomes compared with conventional TKA for patients with end-stage knee osteoarthritis has not been included in economic evaluations of computer-assisted TKA, which are needed to support coverage decisions. This study evaluated the cost-effectiveness of computer-assisted TKA from a payer's perspective, incorporating recent evidence. METHODS: We compared computer-assisted TKA with conventional TKA with regard to costs (in 2022 U.S. dollars) and quality-adjusted life-years (QALYs) using Markov models for elderly patients (≥65 years of age) and patients who were not elderly (55 to 64 years of age). Costs and QALYs were estimated in the lifetime for elderly patients and in the short term for patients who were not elderly, under a bundled payment program and a Fee-for-Service program. Transition probabilities, costs, and QALYs were retrieved from the literature, a national knee arthroplasty registry, and the National Center for Health Statistics. Threshold and probabilistic sensitivity analyses were conducted to examine the robustness of key estimates used in the base-case analysis. Using projected estimates of TKA utilization, the total cost savings of performing computer-assisted TKA rather than conventional TKA were estimated. RESULTS: Compared with conventional TKA, computer-assisted TKA was associated with higher QALYs and lower costs for both elderly patients and patients who were not elderly, regardless of payment programs, making computer-assisted TKA a favorable treatment option. Widespread adoption of computer-assisted TKA in all U.S. patients would result in an estimated total cost saving of $1 billion for payers. CONCLUSIONS: Compared with conventional TKA, computer-assisted TKA reduces costs to payers while providing favorable outcomes. Payers may consider providing additional payment incentives to providers for performing computer-assisted TKA, to achieve outcome improvement and cost control by facilitating widespread adoption of computer-assisted TKA. LEVEL OF EVIDENCE: Economic and Decision Analysis Level II. See Instructions for Authors for a complete description of levels of evidence.

5.
J Exp Clin Cancer Res ; 43(1): 111, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605400

RESUMO

BACKGROUND: The regulatory role of N6-methyladenosine (m6A) modification in the onset and progression of cancer has garnered increasing attention in recent years. However, the specific role of m6A modification in pulmonary metastasis of colorectal cancer remains unclear. METHODS: This study identified differential m6A gene expression between primary colorectal cancer and its pulmonary metastases using transcriptome sequencing and immunohistochemistry. We investigated the biological function of METTL3 gene both in vitro and in vivo using assays such as CCK-8, colony formation, wound healing, EDU, transwell, and apoptosis, along with a BALB/c nude mouse model. The regulatory mechanisms of METTL3 in colorectal cancer pulmonary metastasis were studied using methods like methylated RNA immunoprecipitation quantitative reverse transcription PCR, RNA stability analysis, luciferase reporter gene assay, Enzyme-Linked Immunosorbent Assay, and quantitative reverse transcription PCR. RESULTS: The study revealed high expression of METTL3 and YTHDF1 in the tumors of patients with pulmonary metastasis of colorectal cancer. METTL3 promotes epithelial-mesenchymal transition in colorectal cancer by m6A modification of SNAIL mRNA, where SNAIL enhances the secretion of CXCL2 through the NF-κB pathway. Additionally, colorectal cancer cells expressing METTL3 recruit M2-type macrophages by secreting CXCL2. CONCLUSION: METTL3 facilitates pulmonary metastasis of colorectal cancer by targeting the m6A-Snail-CXCL2 axis to recruit M2-type immunosuppressive macrophages. This finding offers new research directions and potential therapeutic targets for colorectal cancer treatment.


Assuntos
Neoplasias Colorretais , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Quimiocina CXCL2 , Neoplasias Colorretais/genética , Neoplasias Pulmonares/genética , Metiltransferases/genética
6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 546-555, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38660865

RESUMO

OBJECTIVE: To explore the role of NK cells in allogeneic hematopoietic stem cell micro-transplantation(MST) in the treatment of patients with acute myeloid leukemia(AML). METHODS: Data from 93 AML patients treated with MST at our center from 2013-2018 were retrospectively analyzed. The induction regimen was anthracycline and cytarabine combined with peripheral blood stem cells transplantation mobilization by granulocyte colony stimulating factor (GPBSC), followed by 2-4 courses of intensive treatment with medium to high doses of cytarabine combined with GPBSC after achieving complete remission (CR). The therapeutic effects of one and two courses of MST induction therapy on 42 patients who did not reach CR before transplantation were evaluated. Cox proportional hazards regression analysis was used to analyze the impact of donor NK cell dose and KIR genotype, including KIR ligand mismatch, 2DS1, haplotype, and HLA-Cw ligands on survival prognosis of patients. RESULTS: Forty-two patients received MST induction therapy, and the CR rate was 57.1% after 1 course and 73.7% after 2 courses. Multivariate analysis showed that, medium and high doses of NK cells was significantly associated with improved disease-free survival (DFS) of patients (HR=0.27, P =0.005; HR=0.21, P =0.001), and high doses of NK cells was significantly associated with improved overall survival (OS) of patients (HR=0.15, P =0.000). Donor 2DS1 positive significantly increases OS of patients (HR=0.25, P =0.011). For high-risk patients under 60 years old, patients of the donor-recipient KIR ligand mismatch group had longer DFS compared to the nonmismatch group (P =0.036); donor 2DS1 positive significantly prolonged OS of patients (P =0.009). CONCLUSION: NK cell dose, KIR ligand mismatch and 2DS1 influence the therapeutic effect of MST, improve the survival of AML patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Células Matadoras Naturais , Leucemia Mieloide Aguda , Transplante Homólogo , Humanos , Leucemia Mieloide Aguda/terapia , Estudos Retrospectivos , Citarabina , Intervalo Livre de Doença , Masculino , Feminino , Prognóstico , Indução de Remissão , Fator Estimulador de Colônias de Granulócitos , Adulto , Pessoa de Meia-Idade
7.
Molecules ; 29(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38675600

RESUMO

The natural pesticide phenazine-1-carboxylic acid (PCA) is known to lack phloem mobility, whereas Metalaxyl is a representative phloem systemic fungicide. In order to endow PCA with phloem mobility and also enhance its antifungal activity, thirty-two phenazine-1-carboxylic acid-N-phenylalanine esters conjugates were designed and synthesized by conjugating PCA with the active structure N-acylalanine methyl ester of Metalaxyl. All target compounds were characterized by 1H NMR, 13C NMR and HRMS. The antifungal evaluation results revealed that several target compounds exhibited moderate to potent antifungal activities against Sclerotinia sclerotiorum, Bipolaris sorokiniana, Phytophthora parasitica, Phytophthora citrophthora. In particular, compound F7 displayed excellent antifungal activity against S. sclerotiorum with an EC50 value of 6.57 µg/mL, which was superior to that of Metalaxyl. Phloem mobility study in castor bean system indicated good phloem mobility for the target compounds F1-F16. Particularly, compound F2 exhibited excellent phloem mobility; the content of compound F2 in the phloem sap of castor bean was 19.12 µmol/L, which was six times higher than Metalaxyl (3.56 µmol/L). The phloem mobility tests under different pH culture solutions verified the phloem translocation of compounds related to the "ion trap" effect. The distribution of the compound F2 in tobacco plants further suggested its ambimobility in the phloem, exhibiting directional accumulation towards the apical growth point and the root. These results provide valuable insights for developing phloem mobility fungicides mediated by exogenous compounds.


Assuntos
Alanina , Alanina/análogos & derivados , Fenazinas , Fenazinas/química , Fenazinas/farmacologia , Fenazinas/síntese química , Alanina/química , Alanina/farmacologia , Phytophthora/efeitos dos fármacos , Antifúngicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Floema/metabolismo , Floema/efeitos dos fármacos , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Fungicidas Industriais/farmacologia , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Desenho de Fármacos , Ésteres/química , Ésteres/farmacologia , Ésteres/síntese química
8.
Plant Sci ; 343: 112057, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38460553

RESUMO

The eukaryotic AGC protein kinase subfamily (protein kinase A/ protein kinase G/ protein kinase C-family) is involved in regulating numerous biological processes across kingdoms, including growth and development, and apoptosis. PDK1(3-phosphoinositide-dependent protein kinase 1) is a conserved serine/threonine kinase in eukaryotes, which is both a member of AGC kinase and a major regulator of many other downstream AGC protein kinase family members. Although extensively investigated in model plant Arabidopsis, detailed reports for tobacco PDK1s have been limited. To better understand the functions of PDK1s in tobacco, CRISPR/CAS9 transgenic lines were generated in tetraploid N. tabacum, cv. Samsun (NN) with 5-7 of the 8 copies of 4 homologous PDK1 genes in tobacco genome (NtPDK1a/1b/1c/1d homologs) simultaneously knocked out. Numerous developmental defects were observed in these NtPDK1a/1b/1c/1d CRISPR/CAS9 lines, including cotyledon fusion leaf shrinkage, uneven distribution of leaf veins, convex veins, root growth retardation, and reduced fertility, all of which reminiscence of impaired polar auxin transport. The severity of these defects was correlated with the number of knocked out alleles of NtPDK1a/1b/1c/1d. Consistent with the observation in Arabidopsis, it was found that the polar auxin transport, and not auxin biosynthesis, was significantly compromised in these knockout lines compared with the wild type tobacco plants. The fact that no homozygous plant with all 8 NtPDK1a/1b/1c/1d alleles being knocked out suggested that knocking out 8 alleles of NtPDK1a/1b/1c/1d could be lethal. In conclusion, our results indicated that NtPDK1s are versatile AGC kinases that participate in regulation of tobacco growth and development via modulating polar auxin transport. Our results also indicated that CRISPR/CAS9 technology is a powerful tool in resolving gene redundancy in polyploidy plants.


Assuntos
Arabidopsis , Nicotiana , Nicotiana/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Sistemas CRISPR-Cas , Proteínas Quinases/genética , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
9.
JACS Au ; 4(2): 578-591, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38425915

RESUMO

The self-association of amyloid-ß (Aß) peptide into neurotoxic oligomers is believed to be central to Alzheimer's disease (AD). Copper is known to impact Aß assembly, while disrupted copper homeostasis impacts phenotype in Alzheimer's models. Here we show the presence of substoichiometric Cu(II) has very different impacts on the assembly of Aß40 and Aß42 isoforms. Globally fitting microscopic rate constants for fibril assembly indicates copper will accelerate fibril formation of Aß40 by increasing primary nucleation, while seeding experiments confirm that elongation and secondary nucleation rates are unaffected by Cu(II). In marked contrast, Cu(II) traps Aß42 as prefibrillar oligomers and curvilinear protofibrils. Remarkably, the Cu(II) addition to preformed Aß42 fibrils causes the disassembly of fibrils back to protofibrils and oligomers. The very different behaviors of the two Aß isoforms are centered around differences in their fibril structures, as highlighted by studies of C-terminally amidated Aß42. Arctic and Italian familiar mutations also support a key role for fibril structure in the interplay of Cu(II) with Aß40/42 isoforms. The Cu(II) dependent switch in behavior between nonpathogenic Aß40 wild-type and Aß40 Arctic or Italian mutants suggests heightened neurotoxicity may be linked to the impact of physiological Cu(II), which traps these familial mutants as oligomers and curvilinear protofibrils, which cause membrane permeability and Ca(II) cellular influx.

10.
Front Immunol ; 15: 1344272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545114

RESUMO

Immune Checkpoint Inhibitors (ICIs) therapy has advanced significantly in treating malignant tumors, though most 'cold' tumors show no response. This resistance mainly arises from the varied immune evasion mechanisms. Hence, understanding the transformation from 'cold' to 'hot' tumors is essential in developing effective cancer treatments. Furthermore, tumor immune profiling is critical, requiring a range of diagnostic techniques and biomarkers for evaluation. The success of immunotherapy relies on T cells' ability to recognize and eliminate tumor cells. In 'cold' tumors, the absence of T cell infiltration leads to the ineffectiveness of ICI therapy. Addressing these challenges, especially the impairment in T cell activation and homing, is crucial to enhance ICI therapy's efficacy. Concurrently, strategies to convert 'cold' tumors into 'hot' ones, including boosting T cell infiltration and adoptive therapies such as T cell-recruiting bispecific antibodies and Chimeric Antigen Receptor (CAR) T cells, are under extensive exploration. Thus, identifying key factors that impact tumor T cell infiltration is vital for creating effective treatments targeting 'cold' tumors.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Linfócitos T , Imunoterapia/métodos
11.
Adv Sci (Weinh) ; 11(17): e2306706, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38445888

RESUMO

This study aimed to investigate the association between residential greenness and tinnitus and the potential interaction between greenness and genetic predisposition to tinnitus. The normalized difference vegetation index (NDVI) is used to measure residential greenness. The tinnitus is defined based on self-reported. In the cross-sectional analyses, logistic regression models are used for the baseline sample of the United Kingdom Biobank cohort. In the secondary analysis, a Cox proportional hazard model is used for a subsample of participants who completed the tinnitus questionnaire at follow-up. In the cross-sectional analysis including 106471 participants, higher residential greenness is associated with lower odds of tinnitus for each interquartile range increase in continuous NDVI, with an adjusted odds ratio of 0.97 (95% confidence interval: 0.95 to 0.99) for tinnitus. A similar association is observed in the longitudinal analysis, with an adjusted hazard ratio of 0.92 (95% confidence interval: 0.86 to 0.98) for the association of NDVI increased per interquartile range with incident tinnitus. Moreover, there is a significant interaction between greenness and genetic predisposition to tinnitus (P < 0.05). This study suggested that residential greenness is negatively associated with tinnitus. Greenness and genetic predisposition to tinnitus are found to have a significant interaction.


Assuntos
Predisposição Genética para Doença , Zumbido , Zumbido/genética , Zumbido/epidemiologia , Humanos , Masculino , Feminino , Predisposição Genética para Doença/genética , Pessoa de Meia-Idade , Estudos Transversais , Reino Unido/epidemiologia , Idoso , Inquéritos e Questionários , Adulto , Estudos de Coortes , Modelos de Riscos Proporcionais , Fatores de Risco
12.
Chemistry ; 30(26): e202400336, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38438303

RESUMO

Here, we combined magnetometry, multi-frequency electronic paramagnetic resonance, and wave function based ab initio calculations to investigate magnetic properties of two high spin Co(II) complexes Co(BDPRP) (BDPRP=2,6-bis((2-(S)-di(4-R)phenylhydroxylmethyl-1-pyrrolidi-nyl)methyl)pyridine, R=H for 8; R=tBu for 9). Complexes 8 and 9 featuring effective D3h symmetry were found to possess D=24.0 and 32.0 cm-1, respectively, in their S=3/2 ground states of 1 e ' ' d x z / y z 4 1 e ' d x y / x 2 - y 2 2 1 a 1 ' d z 2 1 ${{\left(1{{\rm e}}^{{\rm { {^\prime}}}{\rm { {^\prime}}}}\right({d}_{xz/yz}\left)\right)}^{4}{\left(1{{\rm e}}^{{\rm { {^\prime}}}}\right({d}_{{xy/{x}^{2}-y}^{2}}\left)\right)}^{2}{\left(1{{\rm a}}_{1}^{{\rm { {^\prime}}}}\right({d}_{{z}^{2}}\left)\right)}^{1}}$ . Ligand field analyses revealed that the low-lying d-d excited states make either positive or vanishing contributions to D. Hence, total positive D values were measured for 8 and 9, as well as related D3h high spin Co(II) complexes. In contrast, negative D values are usually observed for C3v congeners. In-depth analyses suggested that lowering symmetry from D3h to C3v induces orbital mixing between 1 e d x z / y z ${1{\rm e}\left({d}_{xz/yz}\right)}$ and 2 e d x y / x 2 - y 2 ${2{\rm e}\left({d}_{{xy/{x}^{2}-y}^{2}}\right)}$ and admixes excited state 4 A 2 1 e → 2 e ${{}^{4}{{\rm A}}_{2}\left(1e\to 2e\right)}$ into the ground state. Both factors turn the total D value progressively negative with the increasing distance (δ) of the Co(II) center out of the equatorial plane. Therefore, δ determines the sign and magnitude of final D values of five-coordinate trigonal bipyramidal S=3/2 Co(II) complexes as measured for a series of such species with varying δ.

13.
Int J Hematol ; 119(5): 564-572, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38441775

RESUMO

OBJECTIVE: To describe the features of ETV6::ABL1 AML as well as the clinical treatment and outcomes. METHODS: Clinical data were collected from three patients diagnosed with ETV6::ABL1 AML at Hebei Yanda Lu Daopei Hospital and Beijing Lu Daopei Hospital. Their clinical and laboratory features were analyzed, and the treatment process and outcomes were described. Ten reported cases of ETV6::ABL1 AML from the literature were also included for analysis. RESULTS: The median age of the patients was 34 years, and 2 patients were male. No patient had a history of blood disorders before diagnosis. After relapse, they were referred to our hospital, where the ETV6::ABL1 gene was detected. Unfortunately, Patient 1 died rapidly after leukemia relapse due to severe infection. Patients 2 and 3 received salvage therapy with a dasatinib-containing regimen, followed by allo-HSCT, and are currently alive and disease-free. CONCLUSION: ETV6::ABL1 is a rare but recurrent genetic aberration in AML, and the combined use of fluorescence in situ hybridization and PCR can better identify this fusion gene. Patients carrying ETV6::ABL1 have a high relapse rate and a poor prognosis. TKIs are a reasonable treatment option for this group, and allo-HSCT may be curative.


Assuntos
Variante 6 da Proteína do Fator de Translocação ETS , Leucemia Mieloide Aguda , Proteínas de Fusão Oncogênica , Proteínas Proto-Oncogênicas c-ets , Proteínas Repressoras , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Masculino , Proteínas Proto-Oncogênicas c-ets/genética , Adulto , Proteínas de Fusão Oncogênica/genética , Proteínas Repressoras/genética , Feminino , Proteínas Proto-Oncogênicas c-abl/genética , Pessoa de Meia-Idade , Resultado do Tratamento , Transplante de Células-Tronco Hematopoéticas
14.
Plant Sci ; 342: 112051, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38417717

RESUMO

Salicylic acid (SA) is a key phyto-hormone that is essential for plant immunity. SARD1 (SYSTEMIC ACQUIRED RESISTANCE DEFICIENT 1), a member of the CBP60 (CALMODULIN-BINDING PROTEIN60) gene family, is one of the major transcription factors regulating the expression of the genes in SA biosynthesis. SARD1 has been extensively studied in model plant Arabidopsis. However, the function of SARD1 homologues in SA biosynthesis and immune responses have rarely been investigated in other plant species. In this study, the CRISPR/CAS9 (Clustered Regularly Interspersed Short Palindromic Repeats/CAS9) technology was used in creating transgenic tobacco mutant lines with 6-8 alleles of four NtSARD1 homologous genes (NtSARD1a/1b/1c/1d) knocked out. No significant difference in morphological phenotype was observed between the transgenic knockout lines and the wild type tobacco plants, indicating that knocking out NtSARD1s does not affect the growth and development in tobacco. However, knocking out or partially knocking out of NtSARD1a/b/c/d resulted in a significantly reduced expression of NtICS1, the key gene in SA biosynthesis pathway, and thus the subsequently decreased SA/SAG accumulations in response to Pst DC3000 (Pseudomonas syrangae pv.tomato DC3000) infection, indicating a key role of NtSARD1 genes in SA biosynthesis in tobacco. As a consequence of reduced SA/SAG accumulation, the Pst DC3000-induced expression of NtPR genes as well as the resistance to Pst DC3000 were both significantly reduced in these knockout lines compared with the wild type tobacco plants. Interestingly, the reductions in the SA/SAG level, NtPR gene induction and Pst DC3000 resistance were positively correlated with the number of alleles being knocked out. Furthermore, LUC reporter gene driven by the promoter of NtICS1 containing two G(A/T)AATT(T/G) motifs could be activated by NtSARD1a, suggesting that NtSARD1a could bind to the core G(A/T)AATT(T/G) motifs and thus activate the expression of LUC reporter. Taken together, our results demonstrated that the NtSARD1 proteins play essential roles in SA biosynthesis and immune responses in tobacco. Our results also demonstrated that the CRISPR/CAS9 technology can overcome gene redundancy and is a powerful tool to study gene functions in polyploid plant species.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Salicílico/metabolismo , Nicotiana/genética , Sistemas CRISPR-Cas , Tetraploidia , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Doenças das Plantas , Pseudomonas syringae/fisiologia , Regulação da Expressão Gênica de Plantas
15.
Adv Sci (Weinh) ; : e2308095, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408137

RESUMO

CRISPR-based gene therapies are making remarkable strides toward the clinic. But the large size of most widely used Cas endonucleases including Cas9 and Cas12a restricts their efficient delivery by the adeno-associated virus (AAV) for in vivo gene editing. Being exceptionally small, the recently engineered type V-F CRISPR-Cas12f1 systems can overcome the cargo packaging bottleneck and present as strong candidates for therapeutic applications. In this study, the pairwise editing efficiencies of different engineered Cas12f1/sgRNA scaffold combinations are systemically screened and optimized, and the CasMINI_v3.1/ge4.1 system is identified as being able to significantly boost the gene editing activity. Moreover, packaged into single AAV vectors and delivered via subretinal injection, CasMINI_v3.1/ge4.1 achieves remarkably high in vivo editing efficiencies, over 70% in transduced retinal cells. Further, the efficacy of this Cas12f1 system-based gene therapy to treat retinitis pigmentosa in RhoP23H mice is demonstrated by the therapeutic benefits achieved including rescued visual function and structural preservation. And minimal bystander editing activity is detected. This work advances and expands the therapeutic potential of the miniature Cas12f1 system to support efficient and accurate in vivo gene therapy.

16.
Nat Commun ; 15(1): 1503, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374176

RESUMO

Nickel-rich layered oxide cathodes promise ultrahigh energy density but is plagued by the mechanical failure of the secondary particle upon (de)lithiation. Existing approaches for alleviating the structural degradation could retard pulverization, yet fail to tune the stress distribution and root out the formation of cracks. Herein, we report a unique strategy to uniformize the stress distribution in secondary particle via Kirkendall effect to stabilize the core region during electrochemical cycling. Exotic metal/metalloid oxides (such as Al2O3 or SiO2) is introduced as the heterogeneous nucleation seeds for the preferential growth of the precursor. The calcination treatment afterwards generates a dopant-rich interior structure with central Kirkendall void, due to the different diffusivity between the exotic element and nickel atom. The resulting cathode material exhibits superior structural and electrochemical reversibility, thus contributing to a high specific energy density (based on cathode) of 660 Wh kg-1 after 500 cycles with a retention rate of 86%. This study suggests that uniformizing stress distribution represents a promising pathway to tackle the structural instability facing nickel-rich layered oxide cathodes.

17.
Molecules ; 29(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38257199

RESUMO

To effectively control the infection of plant pathogens, we designed and synthesized a series of phenylthiazole derivatives containing a 1,3,4-thiadiazole thione moiety and screened for their antibacterial potencies against Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, as well as their antifungal potencies against Sclerotinia sclerotiorum, Rhizoctonia solani, Magnaporthe oryzae and Colletotrichum gloeosporioides. The chemical structures of the target compounds were characterized by 1H NMR, 13C NMR and HRMS. The bioassay results revealed that all the tested compounds exhibited moderate-to-excellent antibacterial and antifungal activities against six plant pathogens. Especially, compound 5k possessed the most remarkable antibacterial activity against R. solanacearum (EC50 = 2.23 µg/mL), which was significantly superior to that of compound E1 (EC50 = 69.87 µg/mL) and the commercial agent Thiodiazole copper (EC50 = 52.01 µg/mL). Meanwhile, compound 5b displayed the most excellent antifungal activity against S. sclerotiorum (EC50 = 0.51 µg/mL), which was equivalent to that of the commercial fungicide Carbendazim (EC50 = 0.57 µg/mL). The preliminary structure-activity relationship (SAR) results suggested that introducing an electron-withdrawing group at the meta-position and ortho-position of the benzene ring could endow the final structure with remarkable antibacterial and antifungal activity, respectively. The current results indicated that these compounds were capable of serving as promising lead compounds.


Assuntos
Antifúngicos , Fungicidas Industriais , Tiadiazóis , Antifúngicos/farmacologia , Tionas , Fungicidas Industriais/farmacologia , Antibacterianos/farmacologia
18.
J Org Chem ; 89(3): 1657-1668, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38241608

RESUMO

Herein, we report a heterogeneous visible light-driven preparation of α-alkylated glycine derivatives. This approach employed a ß-ketoenamine-linked covalent organic framework (2D-COF-4) as the heterogeneous photocatalyst and N-hydroxy phthalimide (NHPI) esters as the alkyl radical sources. Numerous glycine derivatives, including dipeptides, were precisely and efficiently alkylated under visible light-driven reaction conditions. Based on the excellent photoactivity and organic reaction compatibility of 2D-COF-4, this alkylation could proceed flexibly in a green solvent (ethanol) without any other additives. The photocatalyst and phthalimide were fruitfully recycled with a simple workup procedure, revealing a high ecoscale value and low environmental factor (E-factor).

20.
J Pediatr Surg ; 59(3): 515-521, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38092651

RESUMO

BACKGROUND: Clostridioides Difficile Infection (CDI) is a serious antibiotic related complication that has been reported among children undergoing treatment of appendicitis. CDI likelihood amongst different empiric antibiotic regimens for appendicitis remains unclear but likely has important implications for antibiotic stewardship. METHODS: A retrospective cohort study of the Pediatric Health Information System was used to examine patients ages 1 through 18 who received operative management of acute appendicitis. Common empiric antibiotic regimens 1) Ceftriaxone & Metronidazole (CM) 2) Piperacillin & Tazobactam (PT) and 3) Cefoxitin were compared. Study outcomes were CDI within 28 days post-appendectomy and 30-day post-appendectomy percutaneous drainage procedures. Subset analyses were repeated to only include hospitals that standardized empiric antibiotic choice. RESULTS: Of 105,911 patients, 220 (0.21 %) developed CDI. CDI was more common in patients that received CM (CM 0.29 % vs PT 0.15 % vs Cefoxitin 0.18 %; P < 0.01). On adjusted analysis, PT was associated with a lower likelihood of CDI (OR, 0.48; 95%CI, 0.31-0.74) compared to CM which was consistent in hospitals with standardized antibiotic choice. Exposure to more unique antibiotic regimens (OR, 1.70; 95 % CI, 1.50-1.93) and higher total antibiotic days (OR, 1.17; 95 % CI 1.13-1.21) were associated with an increased likelihood of CDI. There was no significant difference in the likelihood of post-appendectomy percutaneous drainage between antibiotic regimens. CONCLUSIONS: CDI is rare following appendectomy for pediatric appendicitis. While PT was associated with statistically lower rates of CDI compared to CM, antibiotic stewardship efforts to avoid mixed regimens and decrease overall antibiotic exposure warrant exploration. LEVEL OF EVIDENCE: Level III.


Assuntos
Apendicite , Infecções por Clostridium , Humanos , Criança , Antibacterianos/uso terapêutico , Cefoxitina , Estudos Retrospectivos , Apendicite/tratamento farmacológico , Apendicite/cirurgia , Resultado do Tratamento , Metronidazol/uso terapêutico , Ceftriaxona/efeitos adversos , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/etiologia , Combinação Piperacilina e Tazobactam
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