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1.
Zhongguo Zhong Yao Za Zhi ; 49(3): 691-701, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621873

RESUMO

Mentha canadensis, as a plant with medicinal and culinary uses, holds significant economic value. Jasmonic acid signaling repressor JAZ protein has a crucial role in regulating plant response to adversity stresses. The M. canadensis McJAZ8 gene is cloned and analyzed for protein characterization, protein interactions, and expression patterns, so as to provide genetic resources for molecular breeding of M. canadensis for stress tolerance. This experiment will analyze the protein structural characteristics, subcellular localization, protein interactions, and gene expression of McJAZ8 using bioinformatics, yeast two-hybrid(Y2H), transient expression in tobacco leaves, qRT-PCR, and other technologies. The results show that:(1)The full length of the McJAZ8 gene is 543 bp, encoding 180 amino acids. The McJAZ8 protein contains conserved TIFY and Jas domains and exhibits high homology with Arabidopsis thaliana AtJAZ1 and AtJAZ2.(2)The McJAZ8 protein is localized in the nucleus and cytoplasm.(3)The Y2H results show that McJAZ8 interacts with itself or McJAZ1/3/4/5 proteins to form homologous or heterologous dimers.(4)McJAZ8 is expressed in different tissue, with the highest expression level in young leaves. In terms of leaf sequence, McJAZ8 shows the highest expression level in the fourth leaf and the lowest expression level in the second leaf.(5) In leaves and roots, the expression of McJAZ8 is upregulated to varying degrees under methyl jasmonate(MeJA), drought, and NaCl treatments. The expression of McJAZ8 shows an initial upregulation followed by a downregulation pattern under CdCl_2 treatment. In leaves, the expression of McJAZ8 tends to gradually decrease under CuCl_2 treatment, while in roots, it initially decreases and then increases before decreasing again. In both leaves and roots, the expression of McJAZ8 is downregulated to varying degrees under AlCl_(3 )treatment. This study has enriched the research on jasmonic acid signaling repressor JAZ genes in M. canadensis and provided genetic resources for the molecular breeding of M. canadensis.


Assuntos
Ciclopentanos , Perfilação da Expressão Gênica , Mentha , Oxilipinas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Biologia Computacional , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Filogenia , Estresse Fisiológico/genética
2.
Appl Opt ; 63(10): A70-A77, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568513

RESUMO

Tungsten oxide (W O 3) has been widely used in hydrogen sensing due to its stable chemical properties and high oxygen vacancy diffusion coefficient. However, the response of pure W O 3 to hydrogen is slow, and doping is an effective way to improve the hydrogen sensing performance of W O 3 materials. In this paper, W O 3/P t/P E G/S i O 2 porous film was prepared by the sol-gel method using tungsten powder, H 2 O 2 and C 2 H 5 O H as precursors, polyethylene glycol (PEG) as the pore-forming agent, and tetraethyl orthosilicate (TEOS) as the S i O 2 source material. The sensing properties of the W O 3 composite for hydrogen were characterized by a transmission optical fiber hydrogen sensing system made at home. The process parameters such as water bath time, aging time, W:PEG ratio, and W:TEOS ratio were optimized to improve the sensitivity and response time of the sensing film. The experimental results indicate that the sensitivity is 15.68%, the average response time is 45 s, and the repeatability is up to 98.74% in 16 consecutive tests. The linearity index R 2 is 0.9946 within the hydrogen concentration range of 5000 ppm to 50,000 ppm. The film responds only to H 2 when the concentration of interfering gases (C H 4, CO, C O 2) is 2000 ppm. The hydrogen sensing performance of the optimized film is significantly improved compared with that of the undoped film.

3.
Heliyon ; 10(8): e29866, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681568

RESUMO

Radiofrequency ablation (RFA) is an effective alternative to surgery for managing some malignant solid tumors. However, for medium-to-large tumors (>3 cm), tumors adjacent to large blood vessels, and certain irregular tumors, sublethal radiofrequency hyperthermia (RFH) often produces a margin of ablated tumor owing to the "heat-sink" effect. This effect typically leaves behind viable residual tumors at the margin. Several studies have reported that a sublethal RFH can significantly enhance the efficacy of chemotherapy, radiotherapy, immunotherapy, and gene therapy for malignant solid tumors. The possible mechanisms by which RFH enhances these therapies include heat-induced tissue fracturing, increased permeability of the cytoplasmic membrane, exaggerated cellular metabolism, blockade of the repair pathways of radiation-damaged tumor cells, and activation of the heat shock protein pathways. Therefore, RFA in combination with chemotherapy, radiotherapy, immunotherapy, or gene therapy may help reduce the rates of residual and recurrent tumors after RFA of malignant solid tumors.

4.
Cell Metab ; 36(3): 541-556.e9, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38232736

RESUMO

The roles of platelets/megakaryocytes (MKs), the key components in the blood system, in the tumor microenvironment and antitumor immunity are unclear. In patients with colorectal cancer, the number of platelets was significantly increased in patients with metastasis, and Erbin expression was highly expressed in platelets from patients with metastases. Moreover, Erbin knockout in platelets/MKs suppressed lung metastasis in mice and promoted aggregations of platelets. Mechanistically, Erbin-deficient platelets have increasing mitochondrial oxidative phosphorylation and secrete lipid metabolites like acyl-carnitine (Acar) by abolishing interaction with prothrombotic protein ESAM. Notably, Acar enhanced the activity of mitochondrial electron transport chain complex and mitochondrial oxidative phosphorylation in B cells by acetylation of H3K27 epigenetically. Targeting Erbin in platelets/MKs by a nanovesicle system dramatically attenuated lung metastasis in mice in vivo. Our study identifies an Erbin-mitochondria axis in platelets/MKs, which suppresses B cell-mediated antitumor immunity, suggesting a new way for the treatment of metastasis.


Assuntos
Neoplasias Pulmonares , Megacariócitos , Animais , Humanos , Camundongos , Plaquetas/metabolismo , Neoplasias Pulmonares/metabolismo , Megacariócitos/metabolismo , Mitocôndrias/metabolismo , Processamento de Proteína Pós-Traducional , Microambiente Tumoral
5.
PLoS One ; 19(1): e0297343, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38241413

RESUMO

AIMS: Pleural effusion is not an infrequent complication in patients undergoing continuous ambulatory peritoneal dialysis. However, there is not adequate data to evaluate pleural effusion and prognosis in clinical practice. In this study, we validated this potential association by a multicenter cohort. METHODS: We screened 1,162 patients who met the inclusion criteria with PD. According to the existence of pleural effusion on stable dialysis (4-8 weeks after dialysis initiation), the participants were divided into pleural effusion and non-pleural effusion groups. The hazard ratios (HRs) of all-cause and cause-specific death were estimated with adjustment for demographic characteristics and multiple potential clinical confounders. Subgroup analysis and propensity score matching (PSM) were used to further verify the robustness of the correlation between hydrothorax and prognosis. RESULTS: Pleural effusion was found in 8.9% (104/1162) of PD individuals. After adjusting for the confounding factors, patients with pleural effusion had significantly increased HRs for all-cause death was 3.06 (2.36-3.96) and cardiovascular death was 3.78 (2.67-5.35) compared to those without pleural effusion. However, it was not associated with infectious and other causes of death. After PSM, the HR of all-cause mortality was 3.56 (2.28-5.56). The association trends were consistent in the subgroup sensitivity analysis. CONCLUSION: Pleural effusion is not rare in PD, and is significantly associated with overall and cardiovascular mortality, which is independent of underlying diseases and clinically relevant indicators.


Assuntos
Hidrotórax , Diálise Peritoneal Ambulatorial Contínua , Derrame Pleural , Humanos , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Diálise Renal/efeitos adversos , Derrame Pleural/etiologia , Hidrotórax/etiologia , Prognóstico
7.
J Nutr Sci ; 12: e120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155810

RESUMO

The aim was to assess epidemiological characteristics of the most recent consumption patterns of meat, vegetable, and fruit among representative urban and rural residents aged 60+ years in regional China. In this cross-sectional survey conducted in mid-2018, participants aged 60+ years were randomly chosen from urban and rural communities in Nanjing municipality of China. Meat, vegetable, and fruit intake were assessed with a validated food frequency questionnaire. Multivariate logistic regression models were applied to compute odds ratio (OR) and 95 % confidence interval (CI) to investigate the association of socio-demographic characteristics with a likelihood of meeting intake recommendation. Among the 20 867 participants, 49⋅5 % were men and 45⋅0 % urban elders, and 6⋅5 % aged 80+ years. The mean values of consumption frequency of red meat, white meat, vegetable, and fruit were 2⋅99 ± 2⋅28, 1⋅37 ± 1⋅13, 5⋅24 ± 6⋅43, and 2⋅64 ± 2⋅91 times/week, respectively, among overall participants. Moreover, there were 14⋅9, 23⋅7, and 12⋅1 % of participants meeting intake recommendations of meat, vegetable, and fruit, separately, in this study. After adjustment for potential confounders, age, gender, residence area, and educational attainment each was associated with the likelihood of meeting intake recommendation of meat, vegetable, or fruit. The consumption frequency and proportion of participants meeting intake recommendations of meat, vegetable, or fruit were not high among elders in regional China. Socio-demographic characteristics were associated with intake recommendations of meat, vegetables, and fruit. It has public health implications that participants' socio-demographic attributes shall be considered for precision intervention on meat, vegetable, and fruit consumption in healthy eating campaigns among elders in China.


Assuntos
Frutas , Verduras , Masculino , Humanos , Idoso , Feminino , Dieta , População Rural , Estudos Transversais , Carne
8.
J Nanobiotechnology ; 21(1): 404, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919724

RESUMO

OBJECTIVE: To investigate the efficacy of an injectable hydrogel loaded with lysed OK-432 (lyOK-432) and doxorubicin (DOX) for residual liver cancer after incomplete radiofrequency ablation (iRFA) of hepatocellular carcinoma (HCC), and explore the underlying mechanism. MATERIALS AND METHODS: The effect of OK-432 and lyOK-432 was compared in activating dendritic cells (DCs). RADA16-I (R) peptide was dissolved in a mixture of lyOK-432 (O) and DOX (D) to develop an ROD hydrogel. The characteristics of ROD hydrogel were evaluated. Tumor response and mice survival were measured after different treatments. The number of immune cells and cytokine levels were measured, and the activation of cGAS/STING/IFN-I signaling pathway in DC was evaluated both in vitro and in vivo. RESULTS: LyOK-432 was more effective than OK-432 in promoting DC maturation and activating the IFN-I pathway. ROD was an injectable hydrogel for effectively loading lyOK-432 and DOX, and presented the controlled-release property. ROD treatment achieved the highest tumor necrosis rate (p < 0.001) and the longest survival time (p < 0.001) compared with the other therapies. The ROD group also displayed the highest percentages of DCs, CD4+ T cells and CD8+ T cells (p < 0.001), the lowest level of Treg cells (p < 0.001), and the highest expression levels of IFN-γ and TNF-α (p < 0.001) compared with the other groups. The expression levels of pSTING, pIRF3, and IFN-ß in DCs were obviously higher after treatment of lyOK-432 in combination with DOX than the other therapies. The surviving mice in the ROD group showed a growth inhibition of rechallenged subcutaneous tumor. CONCLUSION: The novel ROD peptide hydrogel induced an antitumor immunity by activating the STING pathway, which was effective for treating residual liver cancer after iRFA of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ablação por Radiofrequência , Animais , Camundongos , Picibanil/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Carcinoma Hepatocelular/tratamento farmacológico , Hidrogéis/farmacologia , Hidrogéis/química , Linfócitos T CD8-Positivos , Doxorrubicina/farmacologia , Doxorrubicina/química , Citocinas
9.
BMC Nephrol ; 24(1): 288, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37775768

RESUMO

BACKGROUND: The prognosis of diabetic peritoneal dialysis patients is poor. HbA1c serves as a crucial indicator for monitoring blood glucose control in patients with diabetes. Nevertheless, the relationship between visit-to-visit HbA1c variability and prognosis in peritoneal dialysis with diabetes remains unclear. METHODS: All participants were categorized into 3 groups based on the HbA1c variability score (HVS), which is the frequency of 0.5% (5.5 mmol/mol) alter in visit-to-visit HbA1c values. Then, the hazard ratio to HVS with all-cause mortality was analyzed using the Cox hazard model, followed by the Fine-Gray competing risk model for major adverse cardiovascular events. Subgroup and sensitivity analysis were conducted to ascertain the robustness of the findings. RESULTS: Eight hundred twenty patients with type 2 diabetes were finally enrolled in this study from 2,855 participants with a mean age of 56.9 ± 14.6 years and a median follow-up time of 44 months [IQR: 27-70], death occurred in 496 (60.2%) individuals. Compared with the lowest category (HVS < 1/3) after being adjusted by potential confounding factors, the hazard ratio for all-cause mortality was 4.59 (3.74-5.64) and the sub-distribution hazard ratio for major adverse cardiovascular events was 1.91 (1.46-2.51) of the highest category (HVS ≥ 2/3). Subgroup interaction and sensitivity analysis, including the adjustment for variables such as time-weighted average HbA1c, HbA1c measurement times and expansion, confirmed the reliability of the results. CONCLUSION: The HVS is related to the risk of poor prognosis in peritoneal dialysis with type 2 diabetes mellitus, independently of clinical multiple variables, and is a novel indicator with clinical guidance.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Diálise Peritoneal , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Glicemia , Reprodutibilidade dos Testes , Prognóstico , Diálise Peritoneal/efeitos adversos , Doenças Cardiovasculares/etiologia , Fatores de Risco
10.
J Agric Food Chem ; 71(37): 13828-13837, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37676277

RESUMO

Zeaxanthin is a carotenoid, a dihydroxy derivative of ß-carotene. Zeaxanthin has antioxidant, anti-inflammatory, anticancer, and neuroprotective properties. In this study, Yarrowia lipolytica was used as a host for the efficient production of zeaxanthin. The strain Y. lipolytica PO1h was used to construct the following engineered strains for carotenoid production since it produced the highest ß-carotene among the Y. lipolytica PO1h- and Y. lipolytica PEX17-HA-derived strains. By regulating the key nodes on the carotenoid pathway through wild and mutant enzyme comparison and successive modular assembly, the ß-carotene concentration was improved from 19.9 to 422.0 mg/L. To provide more precursor mevalonate, heterologous genes mvaE and mvaSMT were introduced to increase the production of ß-carotene by 27.2% to the yield of 536.8 mg/L. The ß-carotene hydroxylase gene crtZ was then transferred, resulting in a yield of zeaxanthin of 326.5 mg/L. The oxidoreductase RFNR1 and CrtZ were then used to further enhance zeaxanthin production, and the yield of zeaxanthin was up to 775.3 mg/L in YPD shake flask.


Assuntos
Engenharia Metabólica , Yarrowia , beta Caroteno , Yarrowia/genética , Zeaxantinas , Carotenoides
11.
Bioresour Technol ; 387: 129688, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37595805

RESUMO

Spermidine is a type of important growth regulator, which involved in the biosynthesis of photosynthetic pigments, and has the function of promoting cell proliferation. In this study, Isochrysis sp. was selected as the research object to explore the effects of spermidine supplementation on the growth of algal cells and fucoxanthin synthesis under different light intensities. The results showed that the cell density (5.40 × 106 cells/mL) of algae were the highest at 11 days under the light intensity of 200 µmol·m-2·s-1 and spermidine content of 150 µM. The contents of diadinoxanthin (1.09 mg/g) and fucoxanthin (6.11 mg/g) were the highest when spermidine was added under low light intensity, and the growth of algal cells and fucoxanthin metabolism were the most significant. In the carotenoid synthesis pathway, PDS (phytoene desaturase) was up-regulated by 1.96 times and VDE (violaxanthin de-epoxidase) was down-regulated by 0.95 times, which may promote fucoxanthin accumulation.


Assuntos
Haptófitas , Espermidina/farmacologia , Luz , Carotenoides
12.
J Agric Food Chem ; 71(6): 2943-2951, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36629355

RESUMO

Astaxanthin is a high-value red pigment and antioxidant widely used in the pharmaceutical, cosmetic, and food industries. However, the hydrophobicity of astaxanthin causes its low bioavailability. Glycosylation can substantially increase the water solubility of astaxanthin, thus enhancing its bioavailability, photostability, and biological activities. In this study, we report for the first time the heterologous production of glycosylated astaxanthin in Yarrowia lipolytica. By appropriate removal of the chloroplast transit peptide, carotenoid 4-hydroxy-ß-ring 4-dehydrogenase (HBFD) and carotenoid ß-ring 4-dehydrogenase (CBFD) from Adonis aestivalis were expressed in a ß-carotene-producing Y. lipolytica strain, resulting in astaxanthin production with a yield of 0.59 mg/L, 0.05 mg/g DCW. This is the first time to successfully construct a plant-derived astaxanthin synthesis pathway in yeast. Modularized assembly of CBFD and HBFD, replacement of the promoter upstream CBFD, increasing the precursor ß-carotene supply, and regulating the expressions of CBFD and HBFD led to a 4.9-fold increase in astaxanthin production (3.46 mg/L). Finally, introduction of crtX from Pantoea ananatis ATCC 19321 into the astaxanthin-producing strain enabled glycosylated astaxanthin production, and the yield reached 1.47 mg/L, which is the highest yield of microbially produced glycosylated astaxanthin reported to date.


Assuntos
Yarrowia , beta Caroteno , beta Caroteno/metabolismo , Glicosilação , Yarrowia/genética , Yarrowia/metabolismo , Carotenoides/metabolismo , Oxirredutases/metabolismo , Engenharia Metabólica/métodos
14.
Front Pharmacol ; 13: 994878, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313381

RESUMO

Airway inflammation and remodeling are critical pathological changes in asthma, and macrophage activation plays a vital role in this process. Sirtuin 1 (SIRT1) reduces airway inflammation by affecting macrophages in asthma. This study aimed to investigate the potential benefit and underlying mechanism of the SIRT1 agonist bergenin as a treatment for asthma. We performed in vivo and in vitro experiments by establishing a Sirt1 fl/fl -LysMcre mouse asthma model and using the alveolar macrophage-like cell line MH-S, respectively. Our results show that Sirt1 fl/fl -LysMcre asthmatic mice exhibited more severe airway inflammation and airway remodeling than wild-type mice. As an activator of SIRT1, bergenin attenuated asthmatic airway pathology and reduced production of interleukins 1ß, IL-5, IL-6, and matrix metalloproteinase 9 (MMP-9) in wild-type asthmatic mice. However, the therapeutic effects of bergenin were significantly attenuated in Sirt1 fl/fl -LysMcre asthmatic mice or following coadministration with the SIRT1 inhibitor EX-527. Further experiments showed that activation of SIRT1 by bergenin deacetylates nuclear factor κB and hinders its nuclear translocation, thereby affecting IL-1ß, IL-5, IL-6, and MMP-9 production by regulating transcriptional activity. Our study suggests that bergenin can improve asthma-induced airway inflammation and remodeling by activating SIRT1 in macrophages.

15.
Antiviral Res ; 207: 105421, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36150523

RESUMO

Orthobunyaviruses have been reported to cause severe diseases in humans or animals, posing a potential threat to human health and socio-economy. Ebinur lake virus (EBIV) is a newly classified orthobunyavirus, which can induce the histopathogenic change and even the high mortality of infected BALB/c mice. Therefore, it is needed to further study the viral replication and pathogenesis, and develop the therapies to cope with its potential infection to human or animals. Here, through the reverse genetics system, the recombinant EBIV of wild type (rEBIV/WT) and NP-conjugated-eGFP (rEBIV/eGFP/S) were rescued for the application of the high-content screening (HCS) of antiviral drug. The eGFP fluorescence signal of the rEBIV/eGFP/S was stable in the process of successive passage in BHK-21 cells (over 10 passages) and this recombinant virus could replicate in various cell lines. Compared to the wild type EBIV, the rEBIV/eGFP/S caused the smaller plaques (diameter around 1 mm on 3 dpi) and lower peak titers (105 PFU/mL), suggesting attenuation due to the eGFP insertion. Through the high-content screening (HCS) system, two antiviral compounds, ribavirin and favipiravir, which previously reported to have effect to some bunyavirus were tested firstly. Ribavirin showed an inhibitory effect on the rEBIV/eGFP/S (EC50 = 14.38 µM) as our expect, while favipiravir with no inhibitory effect even using high doses. Furthermore, Tyrphostin A9 (EC50 = 0.72 µM for rEBIV/eGFP/S, EC50 = 0.05 µM for EBIV-WT) and UNC0638 (EC50 = 1.26 µM for rEBIV/eGFP/S, EC50 = 1.10 µM for rEBIV/eGFP/S) were identified with strong antiviral effect against EBIV in vitro from 150 antiviral compounds. In addition, the time-of-addition assay indicated that Tyrphostin A9 worked in the stage of viral post-infection, and the UNC0638 in all pre-, co-, and post-infection stages. This robust reverse genetics system will facilitate the investigation into the studying of viral replication and assembly mechanisms, and the development of drug and vaccine for EBIV in the future.


Assuntos
Orthobunyavirus , Amidas , Animais , Antivirais/farmacologia , Genes Reporter , Proteínas de Fluorescência Verde/genética , Humanos , Camundongos , Pirazinas , Ribavirina/farmacologia , Tirfostinas , Replicação Viral
16.
PLoS Negl Trop Dis ; 16(7): e0010642, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35849620

RESUMO

The global impact of mosquito-borne diseases has increased significantly over recent decades. Ebinur Lake virus (EBIV), a newly classified orthobunyavirus, is reported to be highly pathogenic in adult mice. The evaluation of vector competence is essential for predicting the arbovirus transmission risk. Here, Aedes aegypti was applied to evaluate EBIV infection and dissemination in mosquitos. Our experiments indicated that Ae. aegypti had the possibility to spread EBIV (with a transmission rate of up to 11.8% at 14 days post-infection) through biting, with the highest viral dose in a single mosquito's saliva reaching 6.3 plaque-forming units. The highest infection, dissemination and ovary infection rates were 70%, 42.9%, and 29.4%, respectively. The high viral infection rates in Ae. aegypti ovaries imply the possibility of EBIV vertical transmission. Ae. aegypti was highly susceptible to intrathoracic infection and the saliva-positive rate reached 90% at 10 days post-infection. Transcriptomic analysis revealed Toll and Imd signaling pathways were implicated in the mosquito's defensive response to EBIV infection. Defensin C and chitinase 10 were continuously downregulated in mosquitoes infected via intrathoracic inoculation of EBIV. Comprehensive analysis of the vector competence of Ae. aegypti for EBIV in laboratory has indicated the potential risk of EBIV transmission through mosquitoes. Moreover, our findings support a complex interplay between EBIV and the immune system of mosquito, which could affect its vector competence.


Assuntos
Aedes , Orthobunyavirus , Infecção por Zika virus , Zika virus , Animais , Feminino , Imunidade , Camundongos , Mosquitos Vetores , Carga Viral , Zika virus/fisiologia
17.
J Virol ; 96(7): e0217321, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35266805

RESUMO

The Bunyavirales contain many important human pathogens that lack an antiviral therapy. The cap-snatching endonuclease (EN) of segmented negative-strand RNA viruses is an attractive target for broad-spectrum antivirals due to its essential role in initiating viral transcription. L-742,001, a previously reported diketo acid inhibitor against influenza virus EN, demonstrated potent EN inhibition and antiviral activity on various bunyaviruses. However, the precise inhibitory mechanism of the compound is still poorly understood. We recently characterized a highly active EN from Ebinur Lake virus (EBIV), a newly identified member of the Orthobunyavirus genus, and obtained its high-resolution structures, paving the way for structure-guided inhibitor development. Here, nine L-742,001 derivatives were designed and synthesized de novo, and their structure-activity relationship with EBIV EN was studied. In vitro biochemical data showed that the compounds inhibited the EBIV EN activity with different levels and could be divided into three categories. Five representative compounds were selected for further cell-based antiviral assay, and the results largely agreed with those of the EN assays. Furthermore, the precise binding modes of L-742,001 and its derivatives in EN were revealed by determining the high-resolution crystal structures of EN-inhibitor complexes, which suggested that the p-chlorobenzene is essential for the inhibitory activity and the flexible phenyl has the greatest exploration potential. This study provides an important basis for the structure-based design and optimization of inhibitors targeting EN of segmented negative-strand RNA viruses. IMPORTANCE The Bunyavirales contain many important human pathogens such as Crimean-Congo hemorrhagic fever virus and Lassa virus that pose serious threats to public health; however, currently there are no specific antiviral drugs against these viruses. The diketo acid inhibitor L-742,001 is a potential drug as it inactivates the cap-snatching endonuclease (EN) encoded by bunyaviruses. Here, we designed and synthesized nine L-742,001 derivatives and assessed the structure-activity relationship using EN of the newly identified Ebinur Lake virus (EBIV) as a research model. Our results revealed that the p-chlorobenzene of this broad-spectrum EN inhibitor is crucial for the inhibitory activity and the flexible phenyl "arm" has the best potential for further optimization. As cap-snatching ENs are present not only in bunyaviruses but also in influenza viruses, our data provide important guidelines for the development of novel and more potent diketo acid-based antiviral drugs against those viruses.


Assuntos
Antivirais , Bunyaviridae , Endonucleases , Proteínas Virais , Antivirais/síntese química , Antivirais/farmacologia , Antivirais/uso terapêutico , Bunyaviridae/enzimologia , Infecções por Bunyaviridae/tratamento farmacológico , Infecções por Bunyaviridae/virologia , Endonucleases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Hidroxibutiratos/uso terapêutico , Piperidinas/química , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Relação Estrutura-Atividade , Proteínas Virais/metabolismo
18.
Front Neurosci ; 16: 825172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35345545

RESUMO

Background: Migraine is a primary neurological disorder associated with complex brain activity. Recently, mounting evidence has suggested that migraine is underpinned by aberrant dynamic brain activity characterized by linear and non-linear changes across a variety of time scales. However, the abnormal dynamic brain activity at different time scales is still unknown in patients with migraine without aura (MWoA). This study aimed to assess the altered patterns of brain activity dynamics over different time scales and the potential pathophysiological mechanisms of alterations in patients with MWoA. Methods: Multiscale entropy in 50 patients and 20 healthy controls (HCs) was calculated to investigate the patterns and altered brain complexity (BC) across five different time scales. Spearman rank correlation analysis between BC in regions showing significant intergroup differences and clinical scores (i.e., frequency of migraine attacks, duration, headache impact test) was conducted in patients with MWoA. Results: The spatial distribution of BC varied across different time scales. At time scale1, BC was higher in the posterior default mode network (DMN) across participants. Compared with HCs, patients with MWoA had higher BC in the DMN and sensorimotor network. At time scale2, BC was mainly higher in the anterior DMN across participants. Patients with MWoA had higher BC in the sensorimotor network. At time scale3, BC was mainly higher in the frontoparietal network across participants. Patients with MWoA had increased BC in the parietal gyrus. At time scale4, BC is mainly higher in the sensorimotor network. Patients with MWoA had higher BC in the postcentral gyrus. At time scale5, BC was mainly higher in the DMN. Patients with MWoA had lower BC in the posterior DMN. In particular, BC values in the precuneus and paracentral lobule significantly correlated with clinical symptoms. Conclusion: Migraine is associated with alterations in dynamic brain activity in the sensorimotor network and DMN over multiple time scales. Time-varying BC within these regions could be linked to instability in pain transmission and modulation. Our findings provide new evidence for the hypothesis of abnormal dynamic brain activity in migraine.

19.
ACS Omega ; 7(4): 3804-3811, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128288

RESUMO

A gas-solid separation fluidized bed, which belongs to dry separation and can save a lot of water resources, is an important method for coal quality improvement. The effect of regional blockage of the air distributor on the fluidization effect was investigated by varying the blockage area and fluidization gas velocity, and the influence law of blockage of an air distributor on bed stability was revealed. In this paper, the micro-differential pressure sensor is used as a testing tool to analyze the regional characteristics of the fluidized bed blockage hole. The results show that when the air distributor is plugged, the standard deviations of the pressure fluctuation are largest at a height of 100 mm, all reaching more than 2.0, and that the pressure fluctuation at the bottom is greater than that at the top. When the plugged area fraction increases from 1/8 to 1/2, the density fluctuation range at the bottom of the plugged area decreases from 0.2 to 0.04 g/cm3, while the range of influence increases from 10 to 16 cm axially. With the increase of fluidization gas velocity, the mixing effect of particles is improved to an extent, and the range of the affected zone is gradually reduced.

20.
J Virol ; 96(6): e0208521, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35044209

RESUMO

The cap-snatching endonuclease (EN) of segmented negative-strand RNA viruses (sNSVs) produces short capped primers for viral transcription by cleaving the host mRNAs. EN requires divalent metals as cofactors for nucleic acid substrates cleavage; however, the detailed mechanism of metal ion-dependent catalysis of ENs remains obscure. In this work, we reported the EN crystal structure of the Ebinur Lake virus (EBIV), an emerging mosquito-borne orthobunyavirus, and investigated its enzymatic properties and metal ion-based catalytic mechanism. In vitro biochemical data showed that EBIV EN is a specific RNA nuclease and prefers to cleave unstructured uridine-rich ssRNA. Structural comparison indicated that the overall structural architecture of EBIV EN is similar to that of other sNSV ENs, while the detailed active site configuration including the binding state of metal ions and the conformation of the LA/LB loop pair is different. Based on sequence conservation analysis, nine active site mutants were constructed, and seven crystal structures of them were determined. Mutations of active site residues associated with the two metal ions (Mn1 and Mn2) coordination abolished EN activity. Crystallographic analyses further revealed that none of these mutants bound two metal ions simultaneously in the active site. Importantly, we found that the perturbation of Mn1-coordination (metal site 1), resulted in the enhancement or elimination of Mn2-coordination (metal site 2). Taken together, our data provide structural evidence to support the two-metal-ion catalytic mechanism of EBIV EN and the correlation of metal binding at the two binding sites, which may be commonly shared by bunyaviruses or other sNSVs. IMPORTANCE The viral endonucleases (ENs) encoded by bunyaviruses and orthomyxoviruses play an essential role in initiating transcription by "snatching" capped primers from the host mRNAs. These ENs are metal-ion-dependent nucleases; however, the details of their catalytic mechanism remain elusive. Here, we reported high-resolution crystal structures of the wild-type and mutant ENs of a novel bunyavirus, the Ebinur Lake virus (EBIV), and revealed the structure and function relationship of EN. The EBIV EN exhibited differences in the details of active site structure compared to its homologues. Our data provided structural evidence to support a two-metal-ion catalytic mechanism of EBIV EN, and found the correlation of metal binding at both binding sites, which might reflect the dynamic structural properties that correlate to EN catalytic function. Taken together, our results revealed the structural characteristics of EBIV EN and made important implications for understanding the catalytic mechanism of cap-snatching ENs.


Assuntos
Endonucleases , Orthobunyavirus , Proteínas Virais , Animais , Catálise , Endonucleases/química , Endonucleases/genética , Endonucleases/metabolismo , Ativação Enzimática/genética , Mutação , Orthobunyavirus/enzimologia , Orthobunyavirus/genética , Capuzes de RNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
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