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1.
J Am Chem Soc ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753972

RESUMO

The development of low-temperature lithium metal batteries (LMBs) encounters significant challenges because of severe dendritic lithium growth during the charging/discharging processes. To date, the precise origin of lithium dendrite formation still remains elusive due to the intricate interplay between the highly reactive lithium metal anode and organic electrolytes. Herein, we unveil the critical role of interfacial defluorination kinetics of localized high-concentration electrolytes (LHCEs) in regulating lithium dendrite formation, thereby determining the performance of low-temperature LMBs. We investigate the impact of solvation structures of LHCEs on low-temperature LMBs by employing tetrahydrofuran (THF) and 2-methyltetrahydrofuran (2-MeTHF) as comparative solvents. The combination of comprehensive characterizations and theoretical simulations reveals that the THF-based LHCE featured with a strong solvation strength exhibits fast interfacial defluorination reaction kinetics, thus leading to the formation of an amorphous and inorganic-rich solid-electrolyte interphase (SEI) that can effectively suppress the growth of lithium dendrites. As a result, the highly reversible Li metal anode achieves an exceptional Coulombic efficiency (CE) of up to ∼99.63% at a low temperature of -30 °C, thereby enabling stable cycling of low-temperature LMB full cells. These findings underscore the crucial role of electrolyte interfacial reaction kinetics in shaping SEI formation and provide valuable insights into the fundamental understanding of electrolyte chemistry in LMBs.

2.
Research (Wash D C) ; 7: 0327, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410280

RESUMO

Exercise can stimulate physiological cardiac growth and provide cardioprotection effect in ischemia/reperfusion (I/R) injury. MiR-210 is regulated in the adaptation process induced by exercise; however, its impact on exercise-induced physiological cardiac growth and its contribution to exercise-driven cardioprotection remain unclear. We investigated the role and mechanism of miR-210 in exercise-induced physiological cardiac growth and explored whether miR-210 contributes to exercise-induced protection in alleviating I/R injury. Here, we first observed that regular swimming exercise can markedly increase miR-210 levels in the heart and blood samples of rats and mice. Circulating miR-210 levels were also elevated after a programmed cardiac rehabilitation in patients that were diagnosed of coronary heart diseases. In 8-week swimming model in wild-type (WT) and miR-210 knockout (KO) rats, we demonstrated that miR-210 was not integral for exercise-induced cardiac hypertrophy but it did influence cardiomyocyte proliferative activity. In neonatal rat cardiomyocytes, miR-210 promoted cell proliferation and suppressed apoptosis while not altering cell size. Additionally, miR-210 promoted cardiomyocyte proliferation and survival in human embryonic stem cell-derived cardiomyocytes (hESC-CMs) and AC16 cell line, indicating its functional roles in human cardiomyocytes. We further identified miR-210 target genes, cyclin-dependent kinase 10 (CDK10) and ephrin-A3 (EFNA3), that regulate cardiomyocyte proliferation and apoptosis. Finally, miR-210 KO and WT rats were subjected to swimming exercise followed by I/R injury. We demonstrated that miR-210 crucially contributed to exercise-driven cardioprotection against I/R injury. In summary, this study elucidates the role of miR-210, an exercise-responsive miRNA, in promoting the proliferative activity of cardiomyocytes during physiological cardiac growth. Furthermore, miR-210 plays an essential role in mediating the protective effects of exercise against cardiac I/R injury. Our findings suggest exercise as a potent nonpharmaceutical intervention for inducing miR-210, which can alleviate I/R injury and promote cardioprotection.

3.
BMC Public Health ; 24(1): 266, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262984

RESUMO

BACKGROUND: Heavy metal pollution has emerged as a significant concern for human health, prompting increased awareness of its potential adverse effects. While previous research has established a connection between heavy metals and liver function biomarkers, the specific relationship between heavy metals and HBV infection remains unexplored. This cross-sectional study aims to investigate the potential correlations between five blood heavy metals - lead, cadmium, mercury, manganese, and selenium - and the presence of HBsAg, HBsAb, and HBcAb in adults. METHODS: The study utilized data from NHANES 2007-2018. Participants were classified into four groups based on their infectious status, and the association between heavy metals and HBV infection was analyzed using multiple logistic regression and stratification analysis. RESULTS: A total of 8431 participants were included, with 5 436 classified as Susceptible, 1 765 as Vaccinated, 865 as Natural Infection, and 103 as Acute/Chronic HBV Infection. The Vaccinated group exhibited a lower mean age (34.52 ± 14.16 years) compared to the other groups. Statistically significant differences in heavy metal concentrations (except selenium) were observed among the groups (P < 0.001). After adjusting for covariates, lead was significantly associated with HBV infection (Q2: OR 2.37, 95%CI 1.04-5.39; Q3: OR 2.34, 95%CI 1.01-5.40), and positive trends were observed for high blood concentrations of mercury (Q4: OR 3.03, 95%CI 1.31-7.04) and manganese (Q4: OR 2.52, 95%CI 1.20-5.28). Furtherly, the presence of lead reduced the protection of HBsAb (Q2: OR 0.84, 95%CI 0.73-0.97; Q3: OR 0.77, 95%CI 0.66-0.90; Q4: OR 0.83, 95%CI 0.70-0.98). Subgroup analysis indicated that cadmium was associated with an increased risk of HBV infection in Asians (OR 1.36, 95%CI 1.03-1.78) and individuals with a BMI range of 25 to 30 (OR 1.60, 95%CI 1.17-2.18). CONCLUSIONS: The study's findings suggest a correlation between elevated blood Pb concentrations and reduced immunization rates against hepatitis B. Individuals with a positive HBsAg exhibit lower blood Se concentrations and higher blood Hg and Mn concentrations.


Assuntos
Hepatite B , Mercúrio , Metais Pesados , Selênio , Adulto , Humanos , Adulto Jovem , Pessoa de Meia-Idade , Vírus da Hepatite B , Estudos Transversais , Cádmio , Manganês , Antígenos de Superfície da Hepatite B , Inquéritos Nutricionais , Anticorpos Anti-Hepatite B
4.
Eur Radiol ; 34(1): 662-672, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37535155

RESUMO

OBJECTIVES: To construct a machine learning model for differentiating Parkinson's disease (PD) and multiple system atrophy (MSA) by using multimodal PET/MRI radiomics and clinical characteristics. METHODS: One hundred and nineteen patients (81 with PD and 38 with MSA) underwent brain PET/CT and MRI to obtain metabolic images ([18F]FDG, [11C]CFT PET) and structural MRI (T1WI, T2WI, and T2-FLAIR). Image analysis included automatic segmentation on MRI, co-registration of PET images onto the corresponding MRI. Radiomics features were then extracted from the putamina and caudate nuclei and selected to construct predictive models. Moreover, based on PET/MRI radiomics and clinical characteristics, we developed a nomogram. Receiver operating characteristic (ROC) curves were performed to evaluate the performance of the models. Decision curve analysis (DCA) was employed to access the clinical usefulness of the models. RESULTS: The combined PET/MRI radiomics model of five sequences outperformed monomodal radiomics models alone. Further, PET/MRI radiomics-clinical combined model could perfectly distinguish PD from MSA (AUC = 0.993), which outperformed the clinical model (AUC = 0.923, p = 0.028) in training set, with no significant difference in test set (AUC = 0.860 vs 0.917, p = 0.390). However, no significant difference was found between PET/MRI radiomics-clinical model and PET/MRI radiomics model in training (AUC = 0.988, p = 0.276) and test sets (AUC = 0.860 vs 0.845, p = 0.632). DCA demonstrated the highest clinical benefit of PET/MRI radiomics-clinical model. CONCLUSIONS: Our study indicates that multimodal PET/MRI radiomics could achieve promising performance to differentiate between PD and MSA in clinics. CLINICAL RELEVANCE STATEMENT: This study developed an optimal radiomics signature and construct model to distinguish PD from MSA by multimodal PET/MRI imaging methods in clinics for parkinsonian syndromes, which achieved an excellent performance. KEY POINTS: •Multimodal PET/MRI radiomics from putamina and caudate nuclei increase the diagnostic efficiency for distinguishing PD from MSA. •The radiomics-based nomogram was developed to differentiate between PD and MSA. •Combining PET/MRI radiomics-clinical model achieved promising performance to identify PD and MSA.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radiômica , Tomografia por Emissão de Pósitrons , Imageamento por Ressonância Magnética , Estudos Retrospectivos
5.
J Environ Radioact ; 272: 107363, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38160503

RESUMO

Release rate estimation is a vital means of revealing the emission process of radionuclides and assessing the environmental consequences in an emergency. Inverse modeling is widely used in emergency cases, but is vulnerable to plume biases in atmospheric dispersion modeling. One promising solution is a model called "Simultaneously Estimates the Release rate And Corrects both the plume range and Transport pattern" (SERACT). This study investigates the feasibility and behavior of SERACT based on four wind tunnel experiments replicating complex dispersion scenarios with both dense buildings and heterogeneous topography. SERACT's performance is compared with that of Tikhonov-regularized inversion and its predecessor. The results demonstrate that SERACT successfully corrects the modeled plume biases and simultaneously improves the release rate estimations in all four complex local-scale scenarios. The release rates retrieved by SERACT provide better agreement with the true release rates than those given by the other methods for all scenarios, with an average deviation of only 5.83%. After correction, the simulated plume reproduces the concentrations at all sites and achieves the best Pearson correlation coefficient (1.00) and fraction of simulations within a factor of 2 of the measurements (1.00); these values are 7.33 and 2.09 times higher, respectively, than those of simulations using release rates obtained using Tikhonov-regularized inversion.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Modelos Teóricos , Monitoramento de Radiação/métodos , Poluentes Radioativos do Ar/análise , Radioisótopos
6.
J Agric Food Chem ; 71(50): 20285-20294, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37971378

RESUMO

There is increasing interest in developing quinoa products due to their unique nutritional value. Starch and protein are the primary components in quinoa, and the interaction between them affects the quality of quinoa products. This study extracted the starch and protein from quinoa and simulated the thermal processing of quinoa to investigate the effects of starch on the solubility and structure of quinoa protein isolates during heat treatment. The structure of quinoa protein isolates was characterized by fluorescence spectroscopy, Fourier transform infrared spectroscopy, laser particle size analysis, and scanning electron microscopy. The results showed that starch decreased protein solubility, and the maximum solubility was obtained after heating for 5 min. After starch addition during heat treatment, the surface charge distribution of protein changed, the degree of protein aggregation increased, the particle size of proteins increased, the thermal stability increased, and the ß-sheet ratio of the proteins increased, suggesting that the protein structure is more ordered, which is the structural foundation of protein solubility decreasing. The research about the interaction between starch and protein and the effects on the solubility of protein could provide a reference for quinoa products processing.


Assuntos
Chenopodium quinoa , Amido , Amido/química , Chenopodium quinoa/química , Temperatura Alta , Solubilidade , Microscopia Eletrônica de Varredura
7.
Angew Chem Int Ed Engl ; 62(50): e202313447, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37885102

RESUMO

Ether-based electrolytes are considered as an ideal electrolyte system for sodium metal batteries (SMBs) due to their superior compatibility with the sodium metal anode (SMA). However, the selection principle of ether solvents and the impact on solid electrolyte interphase formation are still unclear. Herein, we systematically compare the chain ether-based electrolyte and understand the relationship between the solvation structure and the interphasial properties. The linear ether solvent molecules with different terminal group lengths demonstrate remarkably distinct solvation effects, thus leading to different electrochemical performance as well as deposition morphologies for SMBs. Computational calculations and comprehensive characterizations indicate that the terminal group length significantly regulates the electrolyte solvation structure and consequently influences the interfacial reaction mechanism of electrolytes on SMA. Cryogenic electron microscopy clearly reveals the difference in solid electrolyte interphase in various ether-based electrolytes. As a result, the 1,2-diethoxyethane-based electrolyte enables a high Coulombic efficiency of 99.9 %, which also realizes the stable cycling of Na||Na3 V2 (PO4 )3 full cell with a mass loading of ≈9 mg cm-2 over 500 cycles.

8.
Ultrason Sonochem ; 100: 106640, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37816271

RESUMO

The sustainable extraction of saponins was investigated using natural deep eutectic solvents (NADESs) combined with ultrasound-assisted extraction. A novel NADES (butyric acid-urea) that was responsive to ionic strength was designed and used as the extractant. Ultrasound treatment and a catalyst ferric chloride with plant cell wall breaking function were applied to improve the extraction efficiency.Since the solubility of the NADES varied significantly with ionic strength, 95% of NADES was readily separated from the water phase after the addition of sodium chloride, while saponins remained in the water phase for easy collection. The reuse capacity of NADES, the eco-friendliness of the extraction method, and the antioxidant activity of the extract were further evaluated.NADES was continuously recovered and used to extract Polygonatum sibiricum powder: the yield of saponins did not decrease after five cycles of recovery and re-extraction. The penalty point on the "Eco-scale" suggested that the extraction method was "green" (i.e. eco-friendly).Compared with ethanol extracts, the NADES extracts showed a higher saponin concentration and antioxidant activity.The study can contribute to the sustainable and green extraction of hydrophilic active substances in the food and pharmaceutical industries.


Assuntos
Polygonatum , Saponinas , Solventes , Solventes Eutéticos Profundos , Antioxidantes , Extratos Vegetais , Água
9.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 41(4): 405-413, 2023 Aug 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37474472

RESUMO

OBJECTIVES: This study aimed to construct the finite element model of the mandibular first molar with the invisible appliance and explore the dentition movement characteristics of the mandibular first molar when using micro-implant anchorage and different initial positions of the first molar. METHODS: Models of the mandible, tooth, periodontal membrane, and invisible appliance were constructed using cone beam computed tomography (CBCT) data. The two groups were divided into the non-anchorage group and the micro-implant group (between the roots of the first molar and the second molar) based on whether the elastic traction of the micro-implant was assisted or not. The two groups were divided into the following conditions based on the starting position of the first molar: Working condition 1: the distance between the first molar and the second premolar was 0 mm; working condition 2: the distance between the first molar and the second premolar was 1 mm; working condition 3: the distance between the first molar and the second premolar was 2 mm; working condition 4: the distance between the first molar and the second premolar was 3 mm. The data characte-ristics of total displacement and displacement in each direction of dentition were analyzed. RESULTS: In the non-ancho-rage group, all the other teeth showed reverse movement except for the first molar which was moved distally. Meanwhile, in the micro-implant group, except for a small amount of mesial movement of the second molar in wor-king condition 1, the whole dentition in other working conditions presented distal movement and anterior teeth showed lingual movement, among which the distal displacement of the first molar in working condition 4 was the largest. With the change of the initial position of the first molar to the distal, the movement of the first molar to the distal, the premolar to the mesial, and the anterior to the lip increased, while the movement of the second molar to the mesial decreased. CONCLUSIONS: The micro-implant can effectively protect the anterior anchorage, increase the expression rate of molar distancing, and avoid the round-trip movement of the second molar. The initial position of the first molar movement is related to the amount of distancing and the remaining tooth movement.


Assuntos
Dente Molar , Aparelhos Ortodônticos Removíveis , Análise de Elementos Finitos , Dente Pré-Molar , Ligamento Periodontal , Técnicas de Movimentação Dentária/métodos
10.
Angew Chem Int Ed Engl ; 62(31): e202304411, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37269185

RESUMO

The stable cycling of Mg-metal anodes is limited by several problems, including sluggish electrochemical kinetics and passivation at the Mg surface. In this study, we present a high-entropy electrolyte composed of lithium triflate (LiOTf) and trimethyl phosphate (TMP) co-added to magnesium bis(trifluoromethane sulfonyl)imide (Mg(TFSI)2 /1,2-dimethoxyethane (DME) to significantly improve the electrochemical performance of Mg-metal anodes. The as-formed high-entropy Mg2+ -2DME-OTf- -Li+ -DME-TMP solvation structure effectively reduced the Mg2+ -DME interaction in comparison with that observed in traditional Mg(TFSI)2 /DME electrolytes, thereby preventing the formation of insulating components on the Mg-metal anode and promoting its electrochemical kinetics and cycling stability. Comprehensive characterization revealed that the high-entropy solvation structure brought OTf- and TMP to the surface of the Mg-metal anode and promoted the formation of a Mg3 (PO4 )2 -rich interfacial layer, which is beneficial for enhancing Mg2+ conductivity. Consequently, the Mg-metal anode achieved excellent reversibility with a high Coulombic efficiency of 98 % and low voltage hysteresis. This study provides new insights into the design of electrolytes for Mg-metal batteries.

11.
Nat Commun ; 14(1): 2655, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37160951

RESUMO

The electrolyte solvation structure and the solid-electrolyte interphase (SEI) formation are critical to dictate the morphology of lithium deposition in organic electrolytes. However, the link between the electrolyte solvation structure and SEI composition and its implications on lithium morphology evolution are poorly understood. Herein, we use a single-salt and single-solvent model electrolyte system to systematically study the correlation between the electrolyte solvation structure, SEI formation process and lithium deposition morphology. The mechanism of lithium deposition is thoroughly investigated using cryo-electron microscopy characterizations and computational simulations. It is observed that, in the high concentration electrolytes, concentrated Li+ and anion-dominated solvation structure initiate the uniform Li nucleation kinetically and favor the decomposition of anions rather than solvents, resulting in inorganic-rich amorphous SEI with high interface energy, which thermodynamically facilitates the formation of granular Li. On the contrary, solvent-dominated solvation structure in the low concentration electrolytes tends to exacerbate the solvolysis process, forming organic-rich mosaic SEI with low interface energy, which leads to aggregated whisker-like nucleation and growth. These results are helpful to tackle the long-standing question on the origin of lithium dendrite formation and guide the rational design of high-performance electrolytes for advanced lithium metal batteries.

12.
Foodborne Pathog Dis ; 20(4): 158-168, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37062811

RESUMO

Invasive listeriosis is a rare but serious foodborne disease that causes maternal-neonatal, central nervous system, and bloodstream infections. The aim of this study was to assess the whole-genome sequencing (WGS)-based genetic diversity of clinical Listeria monocytogenes isolates over a 7-year period and prove the effect of WGS application in food vehicle investigation. A total of 360 isolates were recovered during 2013 and 2019 through the national listeriosis special surveillance program. Two hundred twenty-six isolates (62.8%) were associated with pregnancy. All isolates belonged to lineage I (214 isolates) or lineage II (146 isolates), with 4 serogroups (46.9% IIb, 39.7% IIa, 12.5% IVb, and 0.8% IIc). All isolates were in 25 clonal complexes (CCs) and 3 singletons, with CC87, CC8, and CC5 being the most common causes of human listeriosis. All clinical isolates were positive for Listeria pathogenicity island 1 (LIPI-1), LIPI-3 was present in 21.4% of isolates and LIPI-4 was detected in 29.2% of isolates. LIPI-4-positive isolates, including CC87, sequence type (ST)619, ST382, CC4, and CC2, have been shown to confer hypervirulence. Fifteen isolates harbored at least one antimicrobial encoding gene, including tet (M), mef (A), msr (D), and dfr (G). The sublineage designations were consistent with CC designations, and 215 distinct cgMLST types (CTs) were classified, the most abundant being CT58 and CT750. In summary, there is a high level of genetic diversity among the clinical isolates. WGS has strengthened listeriosis surveillance and will be implemented for other foodborne bacteria in the National Molecular Tracing Network for Foodborne Disease.


Assuntos
Doenças Transmitidas por Alimentos , Listeria monocytogenes , Listeriose , Recém-Nascido , Humanos , Listeria monocytogenes/genética , Microbiologia de Alimentos , Listeriose/epidemiologia , Listeriose/microbiologia , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , China/epidemiologia
13.
Int J Mol Sci ; 24(8)2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37108503

RESUMO

Actinomycetes are essential sources of numerous bioactive secondary metabolites with diverse chemical and bioactive properties. Lichen ecosystems have piqued the interest of the research community due to their distinct characteristics. Lichen is a symbiont of fungi and algae or cyanobacteria. This review focuses on the novel taxa and diverse bioactive secondary metabolites identified between 1995 and 2022 from cultivable actinomycetota associated with lichens. A total of 25 novel actinomycetota species were reported following studies of lichens. The chemical structures and biological activities of 114 compounds derived from the lichen-associated actinomycetota are also summarized. These secondary metabolites were classified into aromatic amides and amines, diketopiperazines, furanones, indole, isoflavonoids, linear esters and macrolides, peptides, phenolic derivatives, pyridine derivatives, pyrrole derivatives, quinones, and sterols. Their biological activities included anti-inflammatory, antimicrobial, anticancer, cytotoxic, and enzyme-inhibitory actions. In addition, the biosynthetic pathways of several potent bioactive compounds are summarized. Thus, lichen actinomycetes demonstrate exceptional abilities in the discovery of new drug candidates.


Assuntos
Anti-Infecciosos , Líquens , Líquens/química , Ecossistema , Fungos , Antibacterianos/metabolismo , Anti-Infecciosos/farmacologia
14.
Microbiol Spectr ; 11(3): e0028123, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37052485

RESUMO

The histone acetyltransferase (HAT) Gcn5 ortholog is essential for a variety of fungi. Here, we characterize the roles of Ada2 and Ada3, which are functionally linked to Gcn5, in the insect-pathogenic fungus Beauveria bassiana. Loss of Ada2 and Ada3 led to severe hyphal growth defects on rich and minimal media and drastic decreases in blastospore yield and conidiation capacity, with abnormal conidia-producing structures. ΔAda2 and ΔAda3 exhibited a delay in conidial germination and increased sensitivity to multiple chemical stresses and heat shock. Nearly all their pathogenicity was lost, and their ability to secrete extracellular enzymes, Pr1 proteases and chitinases for cuticle degradation was reduced. A yeast two-hybrid assay demonstrated that Ada2 binds to Ada3 and directly interacts with Gcn5, confirming the existence of a yeast-like Ada3-Ada2-Gcn5 HAT complex in this fungus. Additionally, deletion of the Ada genes reduced the activity of Gcn5, especially in the ΔAda2 strain, which was consistent with the acetylation level of histone H3 determined by Western blotting. These results illustrate the dependence of Gcn5 enzyme activity on Ada2 and Ada3 in fungal hyphal growth, asexual development, multiple stress responses, and pathogenicity in B. bassiana. IMPORTANCE The histone acetyltransferase Gcn5 ortholog contributes significantly to the growth and development of various fungi. In this study, we found that Ada2 and Ada3 have critical regulatory effects on Gcn5 enzyme activity and influence the acetylation of histone H3. Deletion of Ada2 or Ada3 decreased the fungal growth rate and asexual conidial yield and increased susceptibility to multiple stresses in Beauveria bassiana. Importantly, Ada genes are vital virulence factors, and their deletion caused the most virulence loss, mainly by inhibiting the activity of a series of hydrolytic enzymes and the dimorphic transition ability. These findings provide a new perspective on the function of the Gcn5 acetyltransferase complex in pathogens.


Assuntos
Beauveria , Proteínas de Saccharomyces cerevisiae , Histonas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Virulência , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Esporos Fúngicos/metabolismo
15.
Materials (Basel) ; 16(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36984088

RESUMO

Anisotropic discontinuity exists widely in rock masses of mines, tunnels, slopes, water conservancy and hydropower projects. The shear characteristics of bolted anisotropic rock joints are extremely important for the stability design of engineering rock mass. However, few scholars have studied the bolted anisotropic rock joint. The different rock properties on both sides of the rock joint, especially the different rock strengths, will greatly affect the deformation characteristics and failure mode of the rock mass. Based on this, a series of shear tests were carried out on the bolted anisotropic rock joint under different normal stresses, and the characteristics of shear stress-shear displacement curve, shear strength, failure characteristics of the rock joint and deformation characteristics of the bolt are discussed. λ is defined as the strength ratio of upper and lower rock on the structural surface. The results show that the effect of λ on the shear stress-shear displacement curve is not obvious at the pre-fracture stage. The shear stress-shear displacement curve at the pre-breaking stage of the bolt presents a softening stage when the normal stress is equal to 0.5 MPa, tends to be horizontal when the normal stress is equal to 1 MPa and presents a hardening stage when the normal stress is greater than 1 MPa. After the bolt is broken, the shear stress-shear displacement curve presents a stepped-down descent. With the increase in λ, the breaking shear stress of the bolt increases. Elliptic failure occurs on the surface of the bolted anisotropic rock joint, and the length of the major axis of the ellipse decreases with the increase in λ value and normal stress. The bolts with different λ values of anisotropic rock joint show "Z-shaped" tensile bending deformation characteristics after shear fracture, and the horizontal and vertical components of the bolt deformation decrease with the increase in λ value and normal stress. The fracture shear displacement of the bolt increases with the increase in normal stress and decreases with the increase in λ value. The research results are helpful to further understand the shear mechanical characteristics and differences of bolted rock joints and provide a reference for solving the engineering problems of the composite layered rock mass.

16.
Microbiol Spectr ; : e0474822, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36786652

RESUMO

As an important chitin-modifying enzyme, chitin deacetylase (CDA) has been characterized in many fungi, but its function in the entomopathogenic fungus Beauveria bassiana remains unclear. Three CDAs with conserved domains of the carbohydrate esterase 4 (CE-4) family were identified in B. bassiana. Disruption of CDA1 resulted in growth restriction of the fungus on medium with chitin as a carbon source or without a carbon source. Deletion of CDA1 and CDA2 led to defects in fungal conidial formation and conidial vitality compared with those of the wild type (WT), and the conidial yield decreased by 25.81% to 47.68%. Inactivation of three CDA genes resulted in a decrease of 20.23% to 27% in the blastospore yield. ΔCDA1 and ΔCDA3 showed 29.33% and 23.34% reductions in cuticular infection virulence, respectively. However, the CDA family may not contribute to hemocoel infection virulence. Additionally, the sporulation of the insect carcass showed that the three gene deletion mutants were 68.45%, 63.84%, and 56.65% less than WT. Penetration experiments with cicada wings and enzyme activity assays were used to further explore the effect of the fungus on chitin metabolism after gene deletion. Although the three gene deletion mutants penetrated the cicada wings successfully and continued to grow on the underlying medium, their colony sizes were reduced by 29.12% to 47.76%. The CDA enzyme activity of ΔCDA1 and ΔCDA3 decreased by 84.76% and 83.04%, respectively. These data showed that members of the CDA family play a different role in fungal growth, conidial quality, and virulence. IMPORTANCE In this study, we report the roles of CDA family in entomopathogenic fungus B. bassiana. Our results indicated that CDA modulates asexual development and regulates fungal virulence by altering chitin deacetylation and metabolic capacity. CDA affected the biological control potential and life history of B. bassiana by affecting its parasitic and saprophytic life. These findings provide novel insights into the roles of multiple CDA paralogues existing in fungal biocontrol agents.

17.
BMC Genomics ; 24(1): 81, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810020

RESUMO

Trichosanthes kirilowii Maxim. (TK) is a dioecious plant in the Cucurbitaceae family of which different sexes have separate medicinal uses. We used Illumina high-throughput sequencing technology to sequence miRNAs from male and female flower buds of TK. We performed bioinformatics analysis, miRNA identification, and target gene prediction on the data obtained from sequencing, and association analysis was performed in combination with the results of a previous transcriptome sequencing study. As a result, there were 80 differentially expressed miRNAs (DESs) between the female and male plants (48 upregulated and 32 downregulated in female plants). Moreover, 27 novel miRNAs in DESs were predicted to have 282 target genes, and 51 known miRNAs were predicted to have 3418 target genes. By establishing a regulatory network between miRNAs and target genes, 12 core genes were screened, including 7 miRNAs and 5 target genes. Among them, tkmiR157a-5p, tkmiR156c, tkmiR156_2, and tkmiR156k_2 jointly target the regulation of tkSPL18 and tkSPL13B. These two target genes are specifically expressed in male and female plants, respectively, and are involved in the biosynthesis process of BR, which is closely related to the sex differentiation process of TK. The identification of these miRNAs will provide a reference for the analysis of the sex differentiation mechanism of TK.


Assuntos
Cucurbitaceae , MicroRNAs , Trichosanthes , Trichosanthes/genética , MicroRNAs/genética , Regulação da Expressão Gênica de Plantas , Cucurbitaceae/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos
18.
Chemistry ; 29(3): e202202380, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36210331

RESUMO

Sodium metal batteries (SMBs) have been widely studied owing to their relatively high energy density and abundant resources. However, they still need systematic improvement to fulfill the harsh operating conditions for their commercialization. In this review, we summarize the recent progress in SMBs in terms of sodium anode modification, electrolyte exploration, and cathode design. Firstly, we give an overview of the current challenges facing Na metal anodes and the corresponding solutions. Then, the traditional liquid electrolytes and the prospective solid electrolytes for SMBs are summarized. In addition, insertion- and conversion-type cathode materials are introduced. Finally, an outlook for the future of practical SMBs is provided.

19.
Front Cell Infect Microbiol ; 13: 1327092, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38264733

RESUMO

Objective: Nontyphoidal Salmonella is a significant public health concern due to its ability to cause foodborne illnesses worldwide. This study aims to characterize the nontyphoidal Salmonella strains isolated from patients in China. Methods: A total of 19 nontyphoidal Salmonella strains were characterized through serovar identification, antimicrobial susceptibility testing (AST), biofilm formation assessment. Genetic relatedness was determined using pulsed-field gel electrophoresis (PFGE). WGS was employed to decipher the resistance mechanism and to contextualize the S. serovar Mbandaka strains among previously sequenced isolates in China. The biofilm associated mrkA gene was examined by PCR. Results: The predominant serovar identified was S. Enteritidis, followed by S. Mbandaka, S. Thompson, S. Livingston, S. Alachua, and S. Infantis. PFGE analysis indicated a notable genetic similarity among the S. Mbandaka isolates. Phylogenetic analysis suggested that these strains were likely derived from a single source that had persisted in China for over five years. One multidrug resistance (MDR) S. Enteritidis isolate carried a highly transferable IncB/O/K/Z plasmid with bla CTX-M-15. One S. Thompson strain, harboring the mrkABCDF operon in an IncX1 plasmid, isolated from cutaneous lesions, demonstrated robust biofilm formation. However, no mrkABCDF loci were detected in other strains. Conclusion: Our study emphasizes the importance of persisted surveillance and prompt response to Salmonella infections to protect public health. The dissemination of bla CTX-M-15-harboring IncB/O/K/Z plasmid and the spread of virulent mrkABCDF operon among Salmonella in China and other global regions warrant close monitoring.


Assuntos
Salmonella , beta-Lactamases , Humanos , Centros de Atenção Terciária , Sorogrupo , Filogenia , China
20.
Front Vet Sci ; 10: 1269904, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38179331

RESUMO

The Jianshui yellow-brown duck is a unique country-specific waterfowl species in Yunnan Province, well known for its tender meat. However, there is a lack of comprehensive systematic research on the molecular genetic characteristics, especially germplasm resources and economic traits, of the Jianshui yellow-brown ducks. This study investigated the molecular genetic characteristics of Jianshui yellow-brown ducks, compared their selection signals with those of ancestral mallard and meat-type Pekin ducks, and identified genes specific to their meat-use performance. Furthermore, this study also evaluated the breeding potential for its meat performance. In this study, phylogenetic trees, PCA and Admixture analysis were used to investigate the population genetic structure among local duck breeds in China; population genetic differentiation index (Fst), nucleotide diversity and Tajima's D were used to detect selected loci and genes in the population of Jianshui yellow-brown ducks; and transcriptome technology was used to screen for differentially expressed genes in the liver, sebum and breast muscle tissues, and finally, the results of the genome selection signals and transcriptome data were integrated to excavate functional genes affecting the meat performance of the Jianshui yellow-brown ducks. The results of the genetic structure of the population showed that Jianshui yellow-brown ducks were clustered into a separate group. Selection signal analysis indicated significant selection pressure on certain genes related to meat characteristics (ELOVL2, ELOVL3, GDF10, VSTM2A, PHOSPHO1, and IGF2BP1) in both Jianshui yellow-brown ducks and mallards. Transcriptomic data analysis suggested that ELOVL3, PHOSPHO1, and GDF10 are vital candidate genes influencing meat production and quality in Jianshui yellow-brown ducks. A comparison of selection signals between Jianshui yellow-brown ducks and Pekin ducks revealed only 21 selected genes in the Jianshui yellow-brown duck population, and no significant genes were related to meat traits. Moreover, whole-genome resequencing data suggested that the Jianshui yellow-brown duck represents a unique category with distinct genetic mechanisms. Through selection signaling and transcriptomic approaches, we successfully screened and identified important candidate genes affecting meat traits in Jianshui yellow-brown ducks. Furthermore, the Jianshui yellow-brown duck has good potential for improved meat performance, highlighting the need for further improvement.

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