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1.
Nanotechnology ; 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39154654

RESUMO

The exploration of deep space significantly increases the probability of spacecraft failures due to surface electrostatic discharge, which imposes higher vacuum insulation protection requirements on polyimide, the external insulation material of spacecrafts. To address this challenge, this study proposes using silane coupling agent KH550 for organic grafting treatment of Cr2O3 nanoparticles, which are then used to dope and modify polyimide to enhance the vacuum surface insulation of polyimide films. The KH550 grafting improves the interface strength between the fillers and the matrix, allowing the fillers to be uniformly dispersed in the matrix. Compared to pure polyimide films, the prepared PI-Cr2O3@KH550 composite films exhibit significantly enhanced vacuum surface flashover voltage, improved surface/volume resistivity, and dielectric properties. The results demonstrate that polyimide composite films with 0.8% by mass of Cr2O3@KH550 show the most notable performance improvement, with the DC flashover voltage and impulse flashover voltage in vacuum increasing by 20.7% and 27.8%, respectively. The doping of chromium oxide nanoparticles introduces more deep traps into the polyimide films and reduce the surface resistivity. The higher deep trap density inhibits charge migration, thereby alleviating secondary electron emission and surface electric field distortion. Simultaneously, the lower surface resistivity facilitates dissipating surface charges and improves the surface insulation. These findings are of significant reference value for promoting the enhancement of aerospace insulation performance.

2.
Emerg Microbes Infect ; : 2392651, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39155772

RESUMO

AbstractEbola disease is a lethal viral hemorrhagic fever caused by ebolaviruses within the Filoviridae family with case fatality rates of up to 90%. Monoclonal antibody (mAb) based therapies have shown great potential for the treatment of EVD. However, the potential emerging ebolavirus isolates and the negative effect of decoy protein (secreted glycoprotein, sGP) on the therapeutic efficacy of antibodies highlight the necessity of developing novel antibodies to counter the threat of Ebola. Here, 11 fully human mAbs were isolated from transgenic mice immunized with mucin-like domain-deleted GP ectodomain (EBOV GPΔmuc) and recombinant vesicular stomatitis virus-bearing GP (rVSV-EBOV GP). These mAbs were divided into five groups according to their germline genes and exhibited differential binding activities and neutralization capabilities. In particular, three antibodies, 8G6, 2A4, and 5H4 were cross-reactive and could bind at least three ebolavirus glycoproteins. mAb 4C1 not only exhibited neutralizing activity but no cross-reaction with sGP. mAb 7D8 exhibited the strongest neutralizing capacity. Further analysis on the critical residues for the bindings of 4C1 and 8G6 to GPs was conducted using antibodies heavy- and light-chains complementarity-determining regions (CDRs) alanine scanning. It has been shown that light chain CDR3 plays a crucial role in binding and neutralization and that any mutation in CDRs could not improve the binding of 4C1 to sGP. Importantly, mAb 7D8, 8G6, and 4C1 provided complete protection against EBOV infection in a hamster lethal challenge model when administered 12 hours post-infection. These results support mAb 7D8, 8G6, and 4C1 as potent antibody candidates for further investigations and pave the way for further developments of therapies and vaccines.

3.
Free Radic Biol Med ; 223: 357-368, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39127141

RESUMO

Formaldehyde (FA) is a carcinogen that is not only widespread in the environment, but is also produced endogenously by metabolic processes. In organisms, FA is converted to formic acid in a glutathione (GSH)-dependent manner by alcohol dehydrogenase 5 (ADH5). The abnormal accumulation of FA in the body can cause a variety of diseases, especially cognitive impairment leading to Alzheimer's disease (AD). In this study, melatonin derivative 6a (MD6a) markedly improved the survival and chemotactic performance of wild-type Caenorhabditis elegans exposed to high concentrations of FA. MD6a lowered FA levels in the nematodes by enhancing the release of covalently-bound GSH from S-hydroxymethyl-GSH in an adh-5-dependent manner. In addition, MD6a protected against mitochondrial dysfunction and cognitive impairment in beta-amyloid protein (Aß) transgenic nematodes by lowering endogenous FA levels and reducing Aß aggregation in an adh-5-dependent manner. Our findings suggest that MD6a detoxifies FA via ADH5 and protects against Aß toxicity by reducing endogenous FA levels in the C. elegans AD models. Thus, ADH5 might be a potential therapeutic target for FA toxicity and AD.

4.
Genome Med ; 16(1): 98, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138551

RESUMO

BACKGROUND: Cancer-associated fibroblasts (CAFs) are the prominent cell type in the tumor microenvironment (TME), and CAF subsets have been identified in various tumors. However, how CAFs spatially coordinate other cell populations within the liver TME to promote cancer progression remains unclear. METHODS: We combined multi-region proteomics (6 patients, 24 samples), 10X Genomics Visium spatial transcriptomics (11 patients, 25 samples), and multiplexed imaging (92 patients, 264 samples) technologies to decipher the expression heterogeneity, functional diversity, spatial distribution, colocalization, and interaction of fibroblasts. The newly identified CAF subpopulation was validated by cells isolated from 5 liver cancer patients and in vitro functional assays. RESULTS: We identified a liver CAF subpopulation, marked by the expression of COL1A2, COL4A1, COL4A2, CTGF, and FSTL1, and named F5-CAF. F5-CAF is preferentially located within and around tumor nests and colocalizes with cancer cells with higher stemness in hepatocellular carcinoma (HCC). Multiplexed staining of 92 patients and the bulk transcriptome of 371 patients demonstrated that the abundance of F5-CAFs in HCC was associated with a worse prognosis. Further in vitro experiments showed that F5-CAFs isolated from liver cancer patients can promote the proliferation and stemness of HCC cells. CONCLUSIONS: We identified a CAF subpopulation F5-CAF in liver cancer, which is associated with cancer stemness and unfavorable prognosis. Our results provide potential mechanisms by which the CAF subset in the TME promotes the development of liver cancer by supporting the survival of cancer stem cells.


Assuntos
Fibroblastos Associados a Câncer , Carcinoma Hepatocelular , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Microambiente Tumoral , Humanos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Microambiente Tumoral/genética , Proteômica/métodos , Transcriptoma , Regulação Neoplásica da Expressão Gênica , Genômica/métodos , Proliferação de Células , Perfilação da Expressão Gênica , Linhagem Celular Tumoral , Prognóstico , Multiômica
5.
Br J Pharmacol ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982680

RESUMO

BACKGROUND AND PURPOSE: Triple-negative breast cancer (TNBC) has a poor prognosis due to limited therapeutic options. Recent studies have shown that TNBC is highly dependent on mitochondrial oxidative phosphorylation. The aim of this study was to investigate the potential of coptisine, a novel compound that inhibits the complex I of the mitochondrial electron transport chain (ETC), as a treatment for TNBC. EXPERIMENTAL APPROACH: In this study, mitochondrial metabolism in TNBC was analysed by bioinformatics. In vitro and in vivo experiments (in mice) were conducted to evaluate the potential of coptisine as an ETC complex I-targeting therapeutic agent and to investigate the molecular mechanisms underlying coptisine-induced mitochondrial dysfunction. The therapeutic effect of coptisine was assessed in TNBC cells and xenograft mouse model. KEY RESULTS: We demonstrated that mitochondrial ETC I was responsible for this metabolic vulnerability in TNBC. Furthermore, a naturally occurring compound, coptisine, exhibited specific inhibitory activity against this complex I. Treatment with coptisine significantly inhibited mitochondrial functions, reprogrammed cellular metabolism, induced apoptosis and ultimately inhibited the proliferation of TNBC cells. Additionally, coptisine administration induced prominent growth inhibition that was dependent on the presence of a functional complex I in xenograft mouse models. CONCLUSION AND IMPLICATIONS: Altogether, these findings suggest the promising potential of coptisine as a potent ETC complex I inhibitor to target the metabolic vulnerability of TNBC.

6.
PeerJ ; 12: e17333, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948204

RESUMO

Acute heart attack is the primary cause of cardiovascular-related death worldwide. A common treatment is reperfusion of ischemic tissue, which can cause irreversible damage to the myocardium. The number of mitochondria in cardiomyocytes is large, which generate adenosine triphosphate (ATP) to sustain proper cardiac contractile function, and mitochondrial dysfunction plays a crucial role in cell death during myocardial ischemia-reperfusion, leading to an increasing number of studies investigating the impact of mitochondria on ischemia-reperfusion injury. The disarray of mitochondrial dynamics, excessive Ca2+ accumulation, activation of mitochondrial permeable transition pores, swelling of mitochondria, ultimately the death of cardiomyocyte are the consequences of ischemia-reperfusion injury. κ-opioid receptors can alleviate mitochondrial dysfunction, regulate mitochondrial dynamics, mitigate myocardial ischemia-reperfusion injury, exert protective effects on myocardium. The mechanism of κ-OR activation during myocardial ischemia-reperfusion to regulate mitochondrial dynamics and reduce myocardial ischemia-reperfusion injury will be discussed, so as to provide theoretical basis for the protection of ischemic myocardium.


Assuntos
Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , Receptores Opioides kappa , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Receptores Opioides kappa/metabolismo , Humanos , Animais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Dinâmica Mitocondrial/fisiologia , Cálcio/metabolismo
7.
Front Microbiol ; 15: 1410368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873146

RESUMO

Ganoderic acids (GAs) are major functional components of Ganoderma lucidum. The study aimed to breed a new G. lucidum strain with increased contents of individual GAs. Two mating-compatible monokaryotic strains, G. 260125 and G. 260124, were successfully isolated from the dikaryotic G. lucidum CGMCC 5.0026 via protoplast formation and regeneration. The Vitreoscilla hemoglobin gene (vgb) and squalene synthase gene (sqs) were overexpressed in the monokaryotic G. 260124 and G. 260125 strain, respectively. Mating between the G. 260124 strain overexpressing vgb and the G. 260125 strain overexpressing sqs resulted in the formation of the new hybrid dikaryotic G. lucidum strain sqs-vgb. The maximum contents of ganoderic acid (GA)-T, GA-Me, and GA-P in the fruiting body of the mated sqs-vgb strain were 23.1, 15.3, and 39.8 µg/g dry weight (DW), respectively, 2.23-, 1.75-, and 2.69-fold greater than those in G. lucidum 5.0026. The squalene and lanosterol contents increased 2.35- and 1.75-fold, respectively, in the fruiting body of the mated sqs-vgb strain compared with those in the G. lucidum 5.0026. In addition, the maximum expression levels of the sqs and lanosterol synthase gene (ls) were increased 3.23- and 2.13-fold, respectively, in the mated sqs-vgb strain. In summary, we developed a new G. lucidum strain with higher contents of individual GAs in the fruiting body by integrating genetic engineering and mono-mono crossing.

8.
Polymers (Basel) ; 16(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38891399

RESUMO

Designing innovative anode materials that exhibit excellent ion diffusion kinetics, enhanced structural stability, and superior electrical conductivity is imperative for advancing the rapid charge-discharge performance and widespread application of sodium-ion batteries. Hollow-structured materials have received significant attention in electrode design due to their rapid ion diffusion kinetics. Building upon this, we present a high-performance, free-standing MoO2@hollow carbon nanofiber (MoO2@HCNF) electrode, fabricated through facile coaxial electrospinning and subsequent heat treatment. In comparison to MoO2@carbon nanofibers (MoO2@CNFs), the MoO2@HCNF electrode demonstrates superior rate capability, attributed to its larger specific surface area, its higher pseudocapacitance contribution, and the enhanced diffusion kinetics of sodium ions. The discharge capacities of the MoO2@HCNF (MoO2@CNF) electrode at current densities of 0.1, 0.2, 0.5, 1.0, 2.0 and 5.0 A g-1 are 195.55 (155.49), 180.98 (135.20), 163.81 (109.71), 144.05 (90.46), 121.16 (71.21) and 88.90 (44.68) mAh g-1, respectively. Additionally, the diffusion coefficients of sodium ions in the MoO2@HCNFs are 8.74 × 10-12 to 1.37 × 10-12 cm2 s-1, which surpass those of the MoO2@CNFs (6.49 × 10-12 to 9.30 × 10-13 cm2 s-1) during the discharging process. In addition, these prepared electrode materials exhibit outstanding flexibility, which is crucial to the power storage industry and smart wearable devices.

11.
Front Cell Infect Microbiol ; 14: 1341332, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38746783

RESUMO

Introduction: The Crimean-Congo hemorrhagic fever virus (CCHFV), the most geographically widespread tick-borne virus, is endemic in Africa, Eastern Europe and Asia, with infection resulting in mortality in up to 30% of cases. Currently, there are no approved vaccines or effective therapies available for CCHF. The CCHFV should only be manipulated in the BSL-4 laboratory, which has severely hampered basic seroprevalence studies. Methods: In the present study, two antibody detection methods in the forms of an enzyme-linked immunosorbent assay (ELISA) and a surrogate virus neutralization test (sPVNT) were developed using a recombinant glycoprotein (rGP) and a vesicular stomatitis virus (VSV)-based virus bearing the CCHFV recombinant glycoprotein (rVSV/CCHFV) in a biosafety level 2 (BSL-2) laboratory, respectively. Results: The rGP-based ELISA and rVSV/CCHFV-based sVNT were established by using the anti-CCHFV pre-GC mAb 11E7, known as a broadly cross-reactive, potently neutralizing antibody, and their applications as diagnostic antigens were validated for the specific detection of CCHFV IgG and neutralizing antibodies in experimental animals. In two tests, mAb clone 11E7 (diluted at 1:163840 or 512) still displayed positive binding and neutralization, and the presence of antibodies (IgG and neutralizing) against the rGP and rVSV/CCHFV was also determined in the sera from the experimental animals. Both mAb 11E7 and animal sera showed a high reactivity to both antigens, indicating that bacterially expressed rGP and rVSV/CCHFV have good immunoreactivity. Apart from establishing two serological testing methods, their results also demonstrated an imperfect correlation between IgG and neutralizing antibodies. Discussion: Within this limited number of samples, the rGP and rVSV/CCHFV could be safe and convenient tools with significant potential for research on specific antibodies and serological samples.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática , Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Imunoglobulina G , Testes de Neutralização , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Testes de Neutralização/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Febre Hemorrágica da Crimeia/diagnóstico , Febre Hemorrágica da Crimeia/imunologia , Animais , Humanos , Glicoproteínas/imunologia , Testes Sorológicos/métodos , Proteínas Recombinantes/imunologia , Camundongos , Anticorpos Monoclonais/imunologia
12.
Viruses ; 16(4)2024 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-38675892

RESUMO

Canine distemper virus (CDV) can cause fatal infections in giant pandas. Vaccination is crucial to prevent CDV infection in giant pandas. In this study, two bacterium-like particle vaccines F3-GEM and H4-GEM displaying the trimeric F protein or tetrameric H protein of CDV were constructed based on the Gram-positive enhanced-matrix protein anchor (GEM-PA) surface display system. Electron microscopy and Western blot results revealed that the F or H protein was successfully anchored on the surface of GEM particles. Furthermore, one more bacterium-like particle vaccine F3 and H4-GEM was also designed, a mixture consisting of F3-GEM and H4-GEM at a ratio of 1:1. To evaluate the effect of the three vaccines, mice were immunized with F3-GEM, H4-GEM or F3 and H4-GEM. It was found that the level of IgG-specific antibodies and neutralizing antibodies in the F3 and H4-GEM group was higher than the other two groups. Additionally, F3 and H4-GEM also increased the secretion of Th1-related and Th2-related cytokines. Moreover, F3 and H4-GEM induce IgG and neutralizing antibodies' response in dogs. Conclusions: In summary, F3 and H4-GEM can provoke better immune responses to CDV in mice and dogs. The bacterium-like particle vaccine F3 and H4-GEM might be a potential vaccine candidate for giant pandas against CDV infection.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vírus da Cinomose Canina , Cinomose , Vacinas Virais , Animais , Vírus da Cinomose Canina/imunologia , Cães , Camundongos , Cinomose/prevenção & controle , Cinomose/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Feminino , Imunoglobulina G/sangue , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/genética , Camundongos Endogâmicos BALB C , Citocinas/metabolismo , Vacinação
13.
Virus Res ; 345: 199378, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38643857

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a significant threat to human health globally. It is crucial to develop a vaccine to reduce the effect of the virus on public health, economy, and society and regulate the transmission of SARS-CoV-2. Influenza B virus (IBV) can be used as a vector that does not rely on the current circulating influenza A strains. In this study, we constructed an IBV-based vector vaccine by inserting a receptor-binding domain (RBD) into a non-structural protein 1 (NS1)-truncated gene (rIBV-NS110-RBD). Subsequently, we assessed its safety, immunogenicity, and protective efficacy against SARS-CoV-2 in mice, and observed that it was safe in a mouse model. Intranasal administration of a recombinant rIBV-NS110-RBD vaccine induced high levels of SARS-CoV-2-specific IgA and IgG antibodies and T cell-mediated immunity in mice. Administering two doses of the intranasal rIBV-NS110-RBD vaccine significantly reduced the viral load and lung damage in mice. This novel IBV-based vaccine offers a novel approach for controlling the SARS-CoV-2 pandemic.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Vírus da Influenza B , Camundongos Endogâmicos BALB C , SARS-CoV-2 , Vacinas Atenuadas , Animais , Camundongos , Vírus da Influenza B/imunologia , Vírus da Influenza B/genética , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , SARS-CoV-2/imunologia , SARS-CoV-2/genética , COVID-19/prevenção & controle , COVID-19/imunologia , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Feminino , Administração Intranasal , Humanos , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Imunoglobulina A/sangue , Modelos Animais de Doenças , Imunoglobulina G/sangue , Carga Viral , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia
14.
Sci Rep ; 14(1): 9269, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38649378

RESUMO

Rainwater is the main water source in arid and semiarid areas of the Loess Plateau, where rainfall is generally insufficient, ineffective and underutilized during the growing season. Thus, improving rainwater utilization efficiency is essential for sustainable agricultural development. A new system composed of rainwater harvesting, an infiltrator bucket with multiple holes and mulching (RHM), was designed to maintain soil moisture at a proper level in rain-fed orchards in arid and semiarid areas of the Loess Region of China. However, there is a lack of clarity on the effectiveness of RHM. In this study, changes in the soil environment and the growth and physiology of apricot trees were monitored via two treatments: (1) Rain-harvesting irrigation system (RHM) treatment and (2) traditional orchard treatment (CK) as a baseline. The results showed that (1) RHM could effectively improve soil water storage at depths of 0-45 cm and at a horizontal distance of 40 cm from the trunk. For the 1.4 mm light rain event, the soil water content increased by 6.3-12%, and for the two moderate rains, the soil water content increased by 12-25%. The change in the soil relative water content predicted by the LSTM model is consistent with the overall trend of the measured value and gradually decreases, and the prediction accuracy is high, with an error of 0.65. (2) The average soil temperatures at 5 cm, 20 cm and 40 cm under RHM were 17.0% (2.4 °C), 13.6% (1.9 °C) and 7.5% (1 °C) greater than those under CK, respectively. (3) Compared with the control treatment, RHM improved the growth and WUEL of apricot trees. The results highlighted the efficiency of the RHM system in enhancing the soil environment and regulating the growth and physiology of apricot trees, which has greater popularization value in arid and semiarid areas.

15.
Sci Rep ; 14(1): 6053, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480774

RESUMO

The bioactivity of interferon-γ (IFN-γ) in cancer cells in the tumor microenvironment (TME) is not well understood in the current immunotherapy era. We found that IFN-γ has an immunosuppressive effect on colorectal cancer (CRC) cells. The tumor volume in immunocompetent mice was significantly increased after subcutaneous implantation of murine CRC cells followed by IFN-γ stimulation, and RNA sequencing showed high expression of B7 homologous protein 4 (B7H4) in these tumors. B7H4 promotes CRC cell growth by inhibiting the release of granzyme B (GzmB) from CD8+ T cells and accelerating apoptosis in CD8+ T cells. Furthermore, interferon regulatory factor 1 (IRF1), which binds to the B7H4 promoter, is positively associated with IFN-γ stimulation-induced expression of B7H4. The clinical outcome of patients with CRC was negatively related to the high expression of B7H4 in cancer cells or low expression of CD8 in the microenvironment. Therefore, B7H4 is a biomarker of poor prognosis in CRC patients, and interference with the IFN-γ/IRF1/B7H4 axis might be a novel immunotherapeutic method to restore the cytotoxic killing of CRC cells.


Assuntos
Neoplasias Colorretais , Linfócitos T Citotóxicos , Humanos , Animais , Camundongos , Interferon gama/farmacologia , Linfócitos T CD8-Positivos , Microambiente Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia
16.
Front Microbiol ; 15: 1352989, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435693

RESUMO

Purpureocillium lavendulum is an important biocontrol agent against plant-parasitic nematodes, primarily infecting them with conidia. However, research on the regulatory genes and pathways involved in its conidiation is still limited. In this study, we employed Agrobacterium tumefaciens-mediated genetic transformation to generate 4,870 random T-DNA insertion mutants of P. lavendulum. Among these mutants, 131 strains exhibited abnormal conidiation, and further in-depth investigations were conducted on two strains (designated as #5-197 and #5-119) that showed significantly reduced conidiation. Through whole-genome re-sequencing and genome walking, we identified the T-DNA insertion sites in these strains and determined the corresponding genes affected by the insertions, namely Plhffp and Plpif1. Both genes were knocked out through homologous recombination, and phenotypic analysis revealed a significant difference in conidiation between the knockout strains and the wild-type strain (ku80). Upon complementation of the ΔPlpif1 strain with the corresponding wildtype allele, conidiation was restored to a level comparable to ku80, providing further evidence of the involvement of this gene in conidiation regulation in P. lavendulum. The knockout of Plhffp or Plpif1 reduced the antioxidant capacity of P. lavendulum, and the absence of Plhffp also resulted in decreased resistance to SDS, suggesting that this gene may be involved in the integrity of the cell wall. RT-qPCR showed that knockout of Plhffp or Plpif1 altered expression levels of several known genes associated with conidiation. Additionally, the analysis of nematode infection assays with Caenorhabditis elegans indicated that the knockout of Plhffp and Plpif1 indirectly reduced the pathogenicity of P. lavendulum towards the nematodes. The results demonstrate that Agrobacterium tumefaciens - mediated T-DNA insertion mutagenesis, gene knockout, and complementation can be highly effective for identifying functionally important genes in P. lavendulum.

17.
Front Pharmacol ; 15: 1363212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476326

RESUMO

Both continuous oxidative stress and poly (ADP-ribose) polymerase 1 (PARP-1) activation occur in neurodegenerative diseases such as Parkinson's disease. PARP-1 inhibition can reverse mitochondrial damage and has a neuroprotective effect. In a previous study, we synthesized melatonin derivative 6a (MD6a) and reported that it has excellent antioxidant activity and significantly reduces α-synuclein aggregation in Caenorhabditis elegans; however, the underlying mechanism is largely unknown. In the present study, we revealed that MD6a is a potential PARP-1 inhibitor, leading to mammalian targe of rapamycin/heat shock factor 1 signaling downregulation and reducing heat shock protein 4 and 6 expression, thus helping to maintain protein homeostasis and improve mitochondrial function. Together, these findings suggest that MD6a might be a viable candidate for the prevention and treatment of Parkinson's disease.

18.
Antiviral Res ; 225: 105854, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447647

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with frequent mutations has seriously damaged the effectiveness of the 2019 coronavirus disease (COVID-19) vaccine. There is an urgent need to develop a broad-spectrum vaccine while elucidating the underlying immune mechanisms. Here, we developed a SARS-CoV-2 virus-like particles (VLPs) vaccine based on the Canarypox-virus vector (ALVAC-VLPs) using CRISPR/Cas9. Immunization with ALVAC-VLPs showed the effectively induce SARS-CoV-2 specific T and B cell responses to resist the lethal challenge of mouse adaptive strains. Notably, ALVAC-VLPs conferred protection in golden hamsters against SARS-CoV-2 Wuhan-Hu-1 (wild-type, WT) and variants (Beta, Delta, Omicron BA.1, and BA.2), as evidenced by the prevention of weight loss, reduction in lung and turbinate tissue damage, and decreased viral load. Further investigation into the mechanism of immune response induced by ALVAC-VLPs revealed that toll-like receptor 4 (TLR4) mediates the recruitment of dendritic cells (DCs) to secondary lymphoid organs, thereby initiating follicle assisted T (Tfh) cell differentiation, the proliferation of germinal center (GC) B cells and plasma cell production. These findings demonstrate the immunogenicity and efficacy of the safe ALVAC-VLPs vaccine against SARS-CoV-2 and provide valuable insight into the development of COVID-19 vaccine strategies.


Assuntos
COVID-19 , Vacinas de Partículas Semelhantes a Vírus , Camundongos , Animais , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , Sistemas CRISPR-Cas , Edição de Genes , Anticorpos Antivirais , Anticorpos Neutralizantes
19.
J Cancer Res Clin Oncol ; 150(3): 143, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38504073

RESUMO

OBJECTIVE: To develop and validate a radiomics nomogram based on computed tomography (CT) to distinguish appendiceal mucinous neoplasms (AMNs) from appendicitis with intraluminal fluid (AWIF). METHOD: A total of 211 patients from two medical institutions were retrospectively analysed, of which 109 were pathologically confirmed as having appendicitis with concomitant CT signs of intraluminal fluid and 102 as having AMN. All patients were randomly assigned to a training (147 patients) or validation cohort (64 patients) at a 7:3 ratio. Radiomics features of the cystic fluid area of the appendiceal lesions were extracted from nonenhanced CT images using 3D Slicer software. Minimum redundancy maximum relevance and least absolute shrinkage and selection operator regression methods were employed to screen the radiomics features and develop a radiomics model. Combined radiomics nomogram and clinical-CT models were further developed based on the corresponding features selected after multivariate analysis. Lastly, receiver operating characteristic curves, and decision curve analysis (DCA) were used to assess the models' performances in the training and validation cohorts. RESULTS: A total of 851 radiomics features were acquired from the nonenhanced CT images. Subsequently, a radiomics model consisting of eight selected features was developed. The combined radiomics nomogram model comprised rad-score, age, and mural calcification, while the clinical-CT model contained age and mural calcification. The combined model achieved area under the curves (AUCs) of 0.945 (95% confidence interval [CI]: 0.895, 0.976) and 0.933 (95% CI: 0.841, 0.980) in the training and validation cohorts, respectively, which were larger than those obtained by the radiomics (training cohort: AUC, 0.915 [95% CI: 0.865, 0.964]; validation cohort: AUC, 0.912 [95% CI: 0.843, 0.981]) and clinical-CT models (training cohort: AUC, 0.884 [95% CI: 0.820, 0.931]; validation cohort: AUC, 0.767 [95% CI: 0.644, 0.863]). Finally, DCA showed that the clinical utility of the combined model was superior to that of the clinical CT and radiomics models. CONCLUSION: Our combined radiomics nomogram model constituting radiomics, clinical, and CT features exhibited good performance for differentiating AMN from AWIF, indicating its potential application in clinical decision-making.


Assuntos
Apendicite , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias , Humanos , Apendicite/diagnóstico por imagem , Nomogramas , Radiômica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
20.
J Ethnopharmacol ; 327: 118039, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38479545

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The anti-tumor related diseases of Coptidis Rhizoma (Huanglian) were correlated with its traditional use of removing damp-heat, clearing internal fire, and counteracting toxicity. In the recent years, Coptidis Rhizoma and its components have drawn extensive attention toward their anti-tumor related diseases. Besides, Coptidis Rhizoma is traditionally used as an anti-inflammatory herb. Epiberberine (EPI) is a significant alkaloid isolated from Coptidis Rhizoma, and exhibits multiple pharmacological activities including anti-inflammatory. However, the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis has not been demonstrated clearly. AIM OF THE STUDY: Bone metastatic breast cancer can lead to osteolysis via inflammatory factors-induced osteoclast differentiation and function. In this study, we try to analyze the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis. METHODS: To evaluate whether epiberberine could suppress bone metastatic breast cancer-induced osteolytic damage, healthy female Balb/c mice were intratibially injected with murine triple-negative breast cancer 4T1 cells. Then, we examined the inhibitory effect and underlying mechanism of epiberberine on breast cancer-induced osteoclastogenesis in vitro. Xenograft assay was used to study the effect of epiberberine on breast cancer cells in vivo. Moreover, we also studied the inhibitory effects and underlying mechanisms of epiberberine on RANKL-induced osteoclast differentiation and function in vitro. RESULTS: The results show that epiberberine displayed potential therapeutic effects on breast cancer-induced osteolytic damage. Besides, our results show that epiberberine inhibited breast cancer cells-induced osteoclast differentiation and function by inhibiting secreted inflammatory cytokines such as IL-8. Importantly, we found that epiberberine directly inhibited RANKL-induced differentiation and function of osteoclast without cytotoxicity. Mechanistically, epiberberine inhibited RANKL-induced osteoclastogensis via Akt/c-Fos signaling pathway. Furthermore, epiberberine combined with docetaxel effectively protected against bone loss induced by metastatic breast cancer cells. CONCLUSIONS: Our findings suggested that epiberberine may be a promising natural compound for treating bone metastatic breast cancer-induced osteolytic damage by inhibiting IL-8 and is worthy of further exploration in preclinical and clinical trials.


Assuntos
Berberina/análogos & derivados , Neoplasias Ósseas , Neoplasias da Mama , Medicamentos de Ervas Chinesas , Osteólise , Humanos , Feminino , Animais , Camundongos , Osteólise/tratamento farmacológico , Osteólise/metabolismo , Osteólise/patologia , Neoplasias da Mama/patologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/metabolismo , Interleucina-8/metabolismo , Osteoclastos , Osteogênese , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Anti-Inflamatórios/farmacologia , Ligante RANK/metabolismo
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