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There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.
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RNA Mensageiro/genética , RNA Viral/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Células HeLa , Humanos , Imunogenicidade da Vacina , Injeções Intramusculares , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Th1/imunologia , Potência de Vacina , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/administração & dosagem , Vacinas Virais/genéticaRESUMO
It is well-known that highly reactive hydroxyl radicals (HOâ¢) can be produced by the classic Fenton system and our recently discovered haloquinone/H2O2 system, but rarely from thiol-derivatives. Here, we found, unexpectedly, that HO⢠can be generated from H2O2 and thiourea dioxide (TUO2), a widely used and environmentally friendly bleaching agent. A carbon-centered radical and sulfite were detected and identified as the transient intermediates, and urea and sulfate as the final products, with the complementary application of electron spin-trapping, oxygen-18 isotope labeling coupled with HPLC/MS analysis. Density functional theory calculations were conducted to further elucidate the detailed pathways for HO⢠production. Taken together, we proposed that the molecular mechanism for HO⢠generation by TUO2/H2O2: TUO2 tautomerizes from sulfinic acid into ketone isomer (TUO2-K) through proton transfer, then a nucleophilic addition of H2O2 on the S atom of TUO2-K, forming a S-hydroperoxide intermediate TUO2-OOH, which dissociates homolytically to produce HOâ¢. Our findings represent the first experimental and computational study on an unprecedented new molecular mechanism of HO⢠production from simple thiol-derived sulfinic acids, which may have broad chemical, environmental, and biomedical significance for future research on the application of the well-known bleaching agent and its analogs.
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Ultralow temperature-tolerant electronic skins (e-skins) can endow polar robots with tactile feedback for exploring in extremely cold polar environments. However, it remains a challenge to develop e-skins that enable sensitive touch sensation and self-healing at ultralow temperatures. Herein, we describe the development of a sensitive robotic hand e-skin that can stretch, self-heal, and sense at temperatures as low as -78 °C. The elastomeric substrate of this e-skin is based on poly(dimethylsiloxane) supramolecular polymers and multistrength dynamic H-bonds, in particular with quadruple H-bonding motifs (UPy). The structure-performance relationship of the elastomer at ultralow temperatures is investigated. The results show that elastomers with side-chain UPy units exhibit higher stretchability (â¼3257%) and self-healing efficiency compared to those with main-chain UPy units. This is attributed to the lower binding energy variation and lower potential well. Based on the elastomer with side-chain UPy and man-made electric ink, a sensitive robotic hand e-skin for usage at -78 °C is constructed to precisely sense the shape of objects and specific symbols, and its sensation can completely self-recover after being damaged. The findings of this study contribute to the concept of using robotic hands with e-skins in polar environments that make human involvement limited, dangerous, or impossible.
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Elastômeros , Dispositivos Eletrônicos Vestíveis , Humanos , Elastômeros/química , Elasticidade , Pele , EletricidadeRESUMO
BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.
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Protocolos de Quimioterapia Combinada Antineoplásica , Camptotecina , Cetuximab , Neoplasias Colorretais , Fluoruracila , Leucovorina , Neoplasias Hepáticas , Compostos Organoplatínicos , Proteínas Proto-Oncogênicas B-raf , Humanos , Cetuximab/administração & dosagem , Cetuximab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/tratamento farmacológico , Feminino , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Leucovorina/uso terapêutico , Leucovorina/administração & dosagem , Fluoruracila/uso terapêutico , Fluoruracila/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Compostos Organoplatínicos/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/genética , Idoso , Adulto , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Camptotecina/administração & dosagem , Resultado do Tratamento , Proteínas ras/genéticaRESUMO
OBJECTIVES: We explored the epidemiological and molecular characteristics of Candida parapsilosis sensu stricto isolates in China, and their mechanisms of azole resistance. METHODS: Azole susceptibilities of 2318 non-duplicate isolates were determined using CLSI broth microdilution. Isolates were genotyped by a microsatellite typing method. Molecular resistance mechanisms were also studied and functionally validated by CRISPR/Cas9-based genetic alterations. RESULTS: Fluconazole resistance occurred in 2.4% (n = 56) of isolates, and these isolates showed a higher frequency of distribution in ICU inpatients compared with susceptible isolates (48.2%, n = 27/56 versus 27.8%, 613/2208; P = 0.019). Microsatellite-genotyping analysis yielded 29 genotypes among 56 fluconazole-resistant isolates, of which 10 genotypes, including 37 isolates, belonged to clusters, persisting and transmitting in Chinese hospitals for 1-29 months. Clusters harbouring Erg11Y132F (5/10; 50%) were predominant in China. Among these, the second most dominant cluster MT07, including seven isolates, characteristically harbouring Erg11Y132F and Mrr1Q625K, lent its carriage to being one of the strongest associations with cross-resistance and high MICs of fluconazole (>256 mg/L) and voriconazole (2-8 mg/L), causing transmission across two hospitals. Among mutations tested, Mrr1Q625K led to the highest-level increase of fluconazole MIC (32-fold), while mutations located within or near the predicted transcription factor domain of Tac1 (D440Y, T492M and L518F) conferred cross-resistance to azoles. CONCLUSIONS: This study is the first Chinese report of persistence and transmissions of multiple fluconazole-resistant C. parapsilosis sensu stricto clones harbouring Erg11Y132F, and the first demonstration of the mutations Erg11G307A, Mrr1Q625K, Tac1L263S, Tac1D440Y and Tac1T492M as conferring resistance to azoles.
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Candida parapsilosis , Fluconazol , Fluconazol/farmacologia , Candida parapsilosis/genética , Antifúngicos/farmacologia , Azóis/farmacologia , China/epidemiologia , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica/genéticaRESUMO
The practical use of lithium-sulfur batteries faces the "shuttle effect" and lithium dendrite growth. Employing SiO instead of Li metal can fundamentally solve the above problems. Nevertheless, selecting a convenient prelithiation method is essential for normal operation of the battery system. Hence, this work proposed a novel SiO-sulfur battery with preloaded Li3N in a cathode as a prelithiation reagent, which can thoroughly solve the dendrite problem and the side reaction with polysulfides of lithium anode. The S@KB-Li3N vs SiO full cell can obtain a high specific capacity of 790 mAh g-1 after the activation process and be maintained at 478 mAh g-1 after 100 cycles. Our design will provide a new prelithiation strategy for a high-specific-energy SiO-sulfur battery system.
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Heart failure (HF) has emerged as the most pressing health concerns globally, and extant clinical therapies are accompanied by side effects and patients have a high burden of financial. The protein products of nuclear factor erythroid 2-related factor 2 (Nrf2) target genes have a variety of cardioprotective effects, including antioxidant, metabolic functions and anti-inflammatory. By evaluating established preclinical and clinical research in HF to date, we explored the potential of Nrf2 to exert unique cardioprotective functions as a novel therapeutic receptor for HF. In this review, we generalize the progression, structure, and function of Nrf2 research in the cardiovascular system. The mechanism of action of Nrf2 involved in HF as well as agonists of Nrf2 in natural compounds are summarized. Additionally, we discuss the challenges and implications for future clinical translation and application of pharmacology targeting Nrf2. It's critical to developing new drugs for HF.
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Insuficiência Cardíaca , Fator 2 Relacionado a NF-E2 , Transdução de Sinais , Fator 2 Relacionado a NF-E2/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Humanos , Animais , Transdução de Sinais/efeitos dos fármacosRESUMO
A new electrochemical proton-coupled electron transfer method for the intermolecular CSP2-H amination of heteroarenes without oxidants, metal catalysts and external electrolytes has been developed. Various new N-containing heteroarenes were prepared in medium to high yields, and the indole-containing product could be converted into practical 2-oxindole by simple basic hydrolysis. Mechanistic investigation indicated that ester sulfonyl-substituted N-radicals could be formed by the combination of 2,6-lutidine and electrochemical oxidation, which is the key to achieve the desired chemoselectivity.
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OBJECTIVE: The aim of this study was to develop and validate an interpretable and highly generalizable multimodal radiomics model for predicting the prognosis of patients with cerebral hemorrhage. METHODS: This retrospective study involved 237 patients with cerebral hemorrhage from 3 medical centers, of which a training cohort of 186 patients (medical center 1) was selected and 51 patients from medical center 2 and medical center 3 were used as an external testing cohort. A total of 1762 radiomics features were extracted from nonenhanced computed tomography using Pyradiomics, and the relevant macroscopic imaging features and clinical factors were evaluated by 2 experienced radiologists. A radiomics model was established based on radiomics features using the random forest algorithm, and a radiomics-clinical model was further trained by combining radiomics features, clinical factors, and macroscopic imaging features. The performance of the models was evaluated using area under the curve (AUC), sensitivity, specificity, and calibration curves. Additionally, a novel SHAP (SHAPley Additive exPlanations) method was used to provide quantitative interpretability analysis for the optimal model. RESULTS: The radiomics-clinical model demonstrated superior predictive performance overall, with an AUC of 0.88 (95% confidence interval, 0.76-0.95; P < 0.01). Compared with the radiomics model (AUC, 0.85; 95% confidence interval, 0.72-0.94; P < 0.01), there was a 0.03 improvement in AUC. Furthermore, SHAP analysis revealed that the fusion features, rad score and clinical rad score, made significant contributions to the model's decision-making process. CONCLUSION: Both proposed prognostic models for cerebral hemorrhage demonstrated high predictive levels, and the addition of macroscopic imaging features effectively improved the prognostic ability of the radiomics-clinical model. The radiomics-clinical model provides a higher level of predictive performance and model decision-making basis for the risk prognosis of cerebral hemorrhage.
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Currently, the standard treatment for patients who have undergone percutaneous coronary intervention (PCI) following acute myocardial infarction (MI) involves dual antiplatelet therapy (DAPT) with a combination of aspirin and a potent P2Y12 receptor inhibitor. However, the potential benefits of aspirin were partially constrained by the intolerance of some patients. The safety and efficacy of indobufen, an alternative antiplatelet agents to aspirin, in patients with AMI after PCI are yet to be thoroughly investigated.This retrospective study was conducted at a single center and utilized propensity score matching. The enrollment spanned from January 2019 to June 2022, incorporating patients with AMI after PCI. The participants were categorized into two groups based on discharged prescriptions: the aspirin DAPT group and the indobufen DAPT group. The primary endpoint focused on net adverse clinical event (NACE), defined as a composite outcome, including cardiac death, recurrence of MI, definite or probable stent thrombosis (ST), target lesion revascularization (TLR), ischemic stroke and Bleeding Academic Research Consortium (BARC) criteria type 2, 3, or 5. All the patients underwent a one-year follow-up period.A total of 1451 patients were enrolled in this study, with 258 assigned to the indobufen DAPT group and 1193 to the aspirin DAPT group. Following 1:1 propensity score matching, 224 patients were retained in each group. In the indobufen DAPT group, 58 individuals (25.9%) experienced the primary endpoint within one year, compared to 52 individuals (23.2%) in the aspirin DAPT group (HR 1.128, 95% CI 0.776-1.639, p = .527). Specifically, no significant differences were observed in either the efficacy endpoint (MACCE, 20.1% vs. 14.7%, HR 1.392, 95% CI 0.893-2.170, p = .146) or the safety endpoint (BARC 2,3 or 5, 8.04% vs. 10.30%, HR 0.779, p = .427). These findings remained consistent at 1, 3, or 6 months. Additionally, the incidence of gastrointestinal symptoms were significantly lower in indobufen DAPT group compared to the aspirin DAPT group (7.1% vs. 14.3%, p = .022).Our research reveals that the efficacy and safety of indobufen are comparable to aspirin in Chinese patients with AMI following PCI. Given the potential advantages of indobufen in alleviating gastrointestinal symptoms, we propose it as a viable alternative for individuals intolerant to aspirin.
What is the context? Currently, the standard treatment for patients who have undergone percutaneous coronary intervention following acute myocardial infarction involves dual antiplatelet therapy with a combination of aspirin and a potent P2Y12 receptor inhibitor.However, the potential benefits of aspirin were partially constrained by the intolerance of some patients.The safety and efficacy of indobufen, an alternative antiplatelet agents to aspirin, in patients with AMI after PCI are yet to be thoroughly investigated.What is new? While both American and European clinical guidelines recommend the use of indobufen as an alternative treatment for patients who cannot tolerate aspirin, there exists a limited body of research on this subject.Our research is the first to address this gap by comparing the efficacy and safety of indobufen and aspirin in patients with AMI.Our research reveals that the efficacy and safety of indobufen are comparable to aspirin in Chinese patients with AMI following PCI. Given the potential advantages of indobufen in alleviating gastrointestinal symptoms, we propose it as a viable alternative for individuals intolerant to aspirin.What is the impact? These findings might pave the way for further exploration of alternatives to aspirin in patients with AMI.
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Aspirina , Clopidogrel , Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/métodos , Aspirina/uso terapêutico , Masculino , Feminino , Clopidogrel/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Inibidores da Agregação Plaquetária/uso terapêutico , Inibidores da Agregação Plaquetária/farmacologia , Idoso , Resultado do Tratamento , Quimioterapia Combinada/métodosRESUMO
Arabidopsis TEMPRANILLO 1 (TEM1) is a transcriptional repressor that participates in multiple flowering pathways and negatively regulates the juvenile-to-adult transition and the flowering transition. To understand the molecular basis for the site-specific regulation of FLOWERING LOCUS T (FT) by TEM1, we determined the structures of the two plant-specific DNA-binding domains in TEM1, AP2 and B3, in complex with their target DNA sequences from the FT gene 5'-untranslated region (5'-UTR), revealing the molecular basis for TEM1 specificity for its DNA targets. In vitro binding assays revealed that the combination of the AP2 and B3 binding sites greatly enhanced the overall binding of TEM1 to the FT 5'-UTR, indicating TEM1 combinatorically recognizes the FT gene 5'-UTR. We further showed that TEM1 recruits the Polycomb repressive complex 2 (PRC2) to the FT 5'-UTR. The simultaneous binding of the TEM1 AP2 and B3 domains to FT is necessary for deposition of H3K27me3 at the FT 5'-UTR and for the flowering repressor function of TEM1. Overall, our data suggest that the combinatorial recognition of FT 5'-UTR by TEM1 ensures H3K27me3 deposition to precisely regulate the floral transition.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas do Grupo Polycomb/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Flores/genética , Flores/metabolismo , Fotoperíodo , Proteínas do Grupo Polycomb/genética , Fatores de Transcrição/genéticaRESUMO
Light-induced hot carriers derived from the surface plasmons of metal nanostructures have been shown to be highly promising agents for photocatalysis. While both nonthermal and thermalized hot carriers can potentially contribute to this process, their specific role in any given chemical reaction has generally not been identified. Here, we report the observation that the H2-D2 exchange reaction photocatalyzed by Cu nanoparticles is driven primarily by thermalized hot carriers. The external quantum yield shows an intriguing S-shaped intensity dependence and exceeds 100% for high light intensities, suggesting that hot carrier multiplication plays a role. A simplified model for the quantum yield of thermalized hot carriers reproduces the observed kinetic features of the reaction, validating our hypothesis of a thermalized hot carrier mechanism. A quantum mechanical study reveals that vibrational excitations of the surface Cu-H bond is the likely activation mechanism, further supporting the effectiveness of low-energy thermalized hot carriers in photocatalyzing this reaction.
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Early pregnancy loss is a primary cause of low reproductive rates in dairy cows, posing severe economic losses to dairy farming. The accurate diagnosis of dairy cows with early pregnancy loss allows for oestrus synchronization, shortening day open, and increasing the overall conception rate of the herd. Several techniques are available for detecting early pregnancy loss in dairy cows, including rectal ultrasound, circulating blood progesterone, and pregnancy-associated glycoproteins (PAGs). Yet, there is a need to improve on existing techniques and develop novel strategies to identify cows with early pregnancy loss accurately. This manuscript reviews the applications of rectal ultrasound, circulating blood progesterone concentration, and PAGs in the diagnosis of pregnancy loss in dairy cows. The manuscript also discusses the recent progress of new technologies, including colour Doppler ultrasound (CDUS), interferon tau-induced genes (ISGs), and exosomal miRNA in diagnosing pregnancy loss in dairy cows. This study will provide an option for producers to re-breed cows with pregnancy loss, thereby reducing the calving interval and economic costs. Meanwhile, this manuscript might also act as a reference for exploring more economical and precise diagnostic technologies for early pregnancy loss in dairy cows.
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Doenças dos Bovinos , Progesterona , Gravidez , Feminino , Bovinos , Animais , Aborto Animal/diagnóstico , Reprodução , Fertilização , Glicoproteínas , Inseminação Artificial/veterinária , Doenças dos Bovinos/diagnósticoRESUMO
The chlamydospores of Duddingtonia flagrans are an essential survival and reproductive structure and also an effective ingredient for the biocontrol of parasitic nematodes in livestock. In this study, entering and exiting dormancy conditions and predatory activity of the fungal chlamydospores were conducted. During this fungal growth process, the cultivation time is negatively correlated with spore germination rates. After the spores were processed by vacuum drying for 168 h, their germination rate dropped to 0.94%. In contrast, the percentage of living spores remained 54.82%, suggesting that the spores entered structural dormancy in the arid environment. Meanwhile, the efficacies of the spore against Haemonchus contortus larvae were 93.05% (0 h), 92.19% (16 h), 92.77% (96 h), and 86.45% (168 h), respectively. After dormant spores were stored at 4°C, -20°C, and 28°C (RH90 ~ 95%) for 7 days, their germination rate began to increase significantly (p < 0.05). For in vitro predation assay under the condition of 28°C (RH90 ~ 95%), the predation rate was significantly higher on the 7th day after incubation than that on the 3rd day (p < 0.05). During the period when spores were stored at room temperature for 8 months, their germination rate decreased in the first 5 months and then increased slowly to reach a peak in the 7th month. However, the reduction rate of H. contortus L3 in feces captured by spores remained above 71% for the first 7 months. These results will help us increase the end products yield and the quality of biological control of parasitic nematodes in livestock.
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Ascomicetos , Duddingtonia , Haemonchus , Animais , Comportamento Predatório , Controle Biológico de Vetores/métodos , Haemonchus/microbiologia , Fezes/microbiologia , Esporos Fúngicos , Larva/microbiologiaRESUMO
The morphological and structural differences of different types of chlamydospore of Arthrobotrys flagrans, a nematophagous fungus, were studied under light microscope and electron microscope to provide a reference for the biological control of parasitic nematodiasis. In this study, A. flagrans isolate F088 dormant chlamydospore and nondormant chlamydospore were selected as the research objects. The structural differences of these spores were observed by optical microscopy through lactol cotton blue, Trypan blue, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) staining. FunXite -1, 4',6-diamidino-2-phenylindole, and calcofluor white staining were used to observe the metabolic activity, cell wall, and nucleus differences of the two types of spores under fluorescence microscope. Ultrastructure of the two kinds of spores was observed using scanning electron microscope (SEM) and transmission electron microscope (TEM). Since lacto phenol cotton blue, trypan blue staining cannot distinguish dormant spores from dead spores, MTT assay was performed. Fluorescence microscopy observation showed that the cytoplasmic metabolic activity of nondormant spores was stronger than that of dormant spores. The nucleus of dormant spores was bright blue, and their fluorescence was stronger than that of nondormant spores. The cell wall of nondormant spores produced stronger yellow-green fluorescence than that of dormant spores. Ultrastructural observation showed that there were globular protuberances on the surface of the two types of spores but with no significant difference between them. The inner wall of dormant spore possesses a thick zona pellucida with high electron density which was significantly thicker than that of nondormant spores, and their cytoplasm is also changed. In this study, the microstructure characteristics of dormant and nondormant chlamydospores of A. flagrans fungi were preliminarily clarified, suggesting that the state of cell wall and intracellular materials were changed after spores entered to dormancy.
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Ascomicetos , Azul Tripano , Esporos Fúngicos , Fezes/microbiologia , Controle Biológico de VetoresRESUMO
Arthrobotrys flagrans, a nematode-eating fungus, is an effective component of animal parasitic nematode biocontrol agents. In the dried formulation, the majority of spores are in an endogenous dormant state. This study focuses on dormant chlamydospore and nondormant chlamydospore of A. flagrans to investigate the differences in cyclic adenosine monophosphate (cAMP) and protein content between the two types of spores. cAMP and soluble proteins were extracted from the nondormant chlamydospore and dormant chlamydospore of two isolates of A. flagrans. The cAMP Direct Immunoassay Kit and Bradford protein concentration assay kit (Coomassie brilliant blue method) were used to detect the cAMP and protein content in two types of spores. Results showed that the content of cAMP in dormant spores of both isolates was significantly higher than that in nondormant spores (p < 0.05). The protein content of dormant spores in DH055 bacteria was significantly higher than that of nondormant spores (p < 0.05). In addition, the protein content of dormant spores of the SDH035 strain was slightly higher than that of nondormant spores, but the difference was not significant (p > 0.05). The results obtained in this study provide evidence for the biochemical mechanism of chlamydospore dormancy or the germination of the nematophagous fungus A. flagrans.
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AMP Cíclico , Proteínas Fúngicas , Esporos Fúngicos , Esporos Fúngicos/crescimento & desenvolvimento , Proteínas Fúngicas/metabolismo , AMP Cíclico/metabolismo , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/química , Ascomicetos/metabolismo , Ascomicetos/isolamento & purificação , Animais , Nematoides/microbiologiaRESUMO
The method of ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry(UHPLC-Q/Orbitrap HRMS)combined with molecular network was developed in this study for rapidly analyzing the chemical components of the Qinggu San reference sample of classical prescription. Firstly, an ACQUITY UPLC BEH Shield RP_(18) column(2.1 mm×100 mm, 1.7 µm)was used, and acetonitrile and 0.1% formic acid were taken as the mobile phases for gradient elution. The flow rate was 0.4 mL·min~(-1), and the column temperature was 30 â. Under these conditions, the mass spectrum data were collected in both positive and negative ion modes of the heated electrospray ionization source. Subsequently, the mass spectrum data of the Qinggu San reference sample were uploaded to the Global Natural Products Social Molecular Network(GNPS)platform for calculation and analysis, and a visual molecular network was built with Cytoscape 3.8.2 software. On this basis, the chemical components of the Qinggu San reference sample were identified by fragmentation regularity of standard compounds, retention time, accurate relative molecular weight of HR-MS, characteristic fragment ions information, literature, and databases. Finally, a total of 105 chemical components were identified and speculated in the Qinggu San reference sample, including 19 iridoid glycosides, 23 flavonoids, 15 phenylpropanoids, 11 triterpene saponins, and 37 other components. Meanwhile, two of these components are potential new compounds. The method used in this study not only achieved rapid and accurate identification of chemical components in the Qinggu San reference sample and provided a scie-ntific basis for the study of pharmacological substances and quality control of Qinggu San compound preparations but also provided a refe-rence for the rapid identification of chemical components in traditional Chinese medicine compound preparations.
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Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Espectrometria de Massas/métodosRESUMO
Anti-icing coatings on outdoor infrastructures and transportations inevitably suffer from surface injuries, especially in extreme weather events (e.g., freezing weather or acid rain). The coating surface damage can result in anti-icing performance loss or even icing promotion. The development of anti-icing coatings that enables self-healing in extreme conditions is highly desired but still challenging. Herein, an extreme-environment-resistant self-healing anti-icing coating is developed by integrating fluorinated graphene (FG) into a supramolecular polymeric matrix. The coating exhibits both anti-icing and deicing performance (ice nucleation temperature is ≈-30.3 °C; ice shear strength is ≈48.7 kPa), mainly attributable to the hydrophobic FG and silicone-based supramolecular material. Notably, owing to the crosslinking polymeric network with various dynamic bonds, this coating can sustain anti-icing/deicing performance after autonomous self-healing under harsh conditions including low temperature (-20 °C), strong acid (pH = 0), and strong alkali (pH = 14) environments. This coating paves the way to meet the anti-icing demand in open air, especially for the infrastructures in polar regions or acid/alkali environments.
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Upregulation of P2X3 receptor (P2X3R) has been strongly implicated in nociceptive signaling including bone cancer pain (BCP). The present study, using rat bone cancer model, aimed to explore the role of P2X3R in regulating rat pain behavior under the intervention of electroacupuncture (EA). The BCP model was successfully established by injection with MRMT-1 breast cancer cell into the medullary cavity of left tibia for 3 × 104 cells/3 µL PBS in rats as revealed by obvious bone destruction, decreased paw withdrawal thresholds (PWTs), and reduced paw withdrawal latencies (PWLs). Western blot analyses showed that P2X3R expression was significantly upregulated in ipsilateral lumbar 4-6 (L4-6) dorsal root ganglia (DRG), but the difference not seen in spinal cord dorsal horn (SCDH). With the in-depth study of P2X3R activation, we observed that intrathecal injection of P2X3R agonist α,ß-meATP aggravated MRMT-1 induced BCP, while injection of P2X3R inhibitor A-317491 alleviated pain. Subsequently, we demonstrated that BCP induced mechanical allodynia and thermal hyperalgesia were attenuated after EA treatment. Under EA treatment, total P2X3R protein expression in ipsilateral DRGs was decreased, and it is worth mentioning that decreased expression of P2X3R membrane protein, which indicated that both the expression and membrane trafficking of P2X3R were inhibited by EA. The immunofluorescence assay showed that EA stimulation exerted functions by reducing the expression of P2X3R-positive cells in ipsilateral DRGs of BCP rats. Ca2+ imaging analysis revealed that the EA stimulation decreased the percentage of α,ß-meATP responsive neurons in DRGs and inhibited calcium influx. Notably, the inhibitory effect of EA on mechanical allodynia and nociceptive flinches was abolished by intrathecal injection of α,ß-meATP. These findings demonstrated EA stimulation ameliorated mechanical allodynia and thermal hyperalgesia in rat model of MRMT-1-induced BCP. EA exerts analgesic effect on BCP by reducing the overexpression and functional activity of P2X3R in ipsilateral DRGs of BCP rats. Our work first demonstrates the critical and overall role of P2X3R in EA's analgesia against peripheral sensitization of MRMT-1-induced BCP and further supports EA as a potential therapeutic option for cancer pain in clinic.
Assuntos
Neoplasias Ósseas , Dor do Câncer , Eletroacupuntura , Ratos , Animais , Hiperalgesia/metabolismo , Dor do Câncer/metabolismo , Receptores Purinérgicos P2X3/metabolismo , Ratos Sprague-Dawley , Eletroacupuntura/métodos , Dor/metabolismo , Neoplasias Ósseas/metabolismo , Analgésicos , Gânglios Espinais/metabolismoRESUMO
PURPOSE: Fruit intake is beneficial to several chronic diseases, but controversial in diabetes. We aimed to investigate prospectively the associations of whole fresh fruit intake with risk of incident type 2 diabetes (T2D) in subjects with different glucose regulation capacities. METHODS: The present study included 79,922 non-diabetic participants aged ≥ 40 years from an ongoing nationwide prospective cohort in China. Baseline fruit intake information was collected by a validated food frequency questionnaire. Plasma HbA1c, fasting and 2 h post-loading glucose levels were measured at both baseline and follow-up examinations. Cox proportional hazards models were used to calculate hazard ratio (HR) and 95% confidence intervals (CI) for incident diabetes among participants with normal glucose tolerance (NGT) and prediabetes, after adjusted for multiple confounders. Restricted cubic spline analysis was applied for dose-response relation. RESULTS: During a median 3.8-year follow-up, 5886 (7.36%) participants developed diabetes. Overall, we identified a linear and dose-dependent inverse association between dietary whole fresh fruit intake and risk of incident T2D. Each 100 g/d higher fruit intake was associated with 2.8% lower risk of diabetes (HR 0.972, 95%CI [0.949-0.996], P = 0.0217), majorly benefiting NGT subjects with 15.2% lower risk (HR 0.848, 95%CI [0.766-0.940], P = 0.0017), while not significant in prediabetes (HR 0.981, 95%CI 0.957-4.005, P = 0.1268). Similarly, the inverse association was present in normoglycemia individuals with a 48.6% lower risk of diabetes when consuming fruits > 7 times/week comparing to those < 1 time/week (HR 0.514, 95% CI [0.368-0.948]), but not in prediabetes (HR 0.883, 95% CI [0.762-1.023]). CONCLUSION: These findings suggest that higher frequency and amount of fresh fruit intake may protect against incident T2D, especially in NGT, but not in prediabetes, highlighting the dietary recommendation of higher fresh fruit consumption to prevent T2D in normoglycemia population.