Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 72
Filtrar
1.
Small Methods ; : e2301657, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708670

RESUMEN

Memristor possesses great potential and advantages in neuromorphic computing, while consistency and power consumption issues have been hindering its commercialization. Low cost and accuracy are the advantages of human brain, so memristors can be used to construct brain-like synaptic devices to solve these problems. In this work, a five-layer AlOx device with a V-shaped oxygen distribution is used to simulate biological synapses. The device simulates synapse structurally. Further, under electrical stimulation, O2- moves to the Ti electrode and oxygen vacancy (Vo) moves to the Pt electrode, thus forming a conductive filament (CF), which simulates the Ca2+ flow and releases neurotransmitters to the postsynaptic membrane, thus realizing the transmission of information. By controlling applied voltage, the regulation of Ca2+ gated pathway is realized to control the Ca2+ internal flow and achieve different degrees of information transmission. Long-term Potentiation (LTP)/Long-term Depression (LTD), Spike Timing Dependent Plasticity (STDP), these basic synaptic performances can be simulated. The AlOx device realizes low power consumption (56.7 pJ/392 fJ), high switching speed (25 ns/60 ns), and by adjusting the window value, the nonlinearity is improved (0.133/0.084), a high recognition accuracy (98.18%) is obtained in neuromorphic simulation. It shows a great prospect in multi-value storage and neuromorphic computing.

2.
Front Microbiol ; 15: 1362296, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38591035

RESUMEN

Introduction: Arbuscular mycorrhizal fungi (AMF) have been demonstrated their ability to enhance the arsenic (As) tolerance of host plants, and making the utilization of mycorrhizal plants a promising and practical approach for remediating As-contaminated soils. However, comprehensive transcriptome analysis to reveal the molecular mechanism of As tolerance in the symbiotic process between AMF and host plants is still limited. Methods: In this study, transcriptomic analysis of Gossypium seedlings was conducted with four treatments: non-inoculated Gossypium under non-As stress (CK0), non-inoculated Gossypium under As stress (CK100), F. mosseae-inoculated Gossypium under non-As stress (FM0), and F. mosseae-inoculated Gossypium under As stress (FM100). Results: Our results showed that inoculation with F. mosseae led to a reduction in net fluxes of Ca2+, while increasing Ca2+ contents in the roots and leaves of Gossypium under the same As level in soil. Notably, 199 and 3129 differentially expressed genes (DEGs) were specially regulated by F. mosseae inoculation under As stress and non-As stress, respectively. Through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation and enrichment analyses, we found that under As stress, F. mosseae inoculation up-regulated a significant number of genes related to the Ca2+ signaling pathway genes, involved in cellular process, membrane part, and signal transduction. This suggests a potential role in mitigating As tolerance in Gossypium seedlings. Furthermore, our analysis identified specific DEGs in transcription factor families, including ERF, MYB, NAC, and WRKY, that were upregulated by F. mosseae inoculation. Conversely, MYB and HB-other were down-regulated. The ERF and MYB families exhibited the highest number of up- and down-regulated DEGs, respectively, which were speculated to play an important role in alleviating the As toxicity of Gossypium. Discussion: Our findings provided valuable insights into the molecular theoretical basis of the Ca2+ signaling pathway in improving As tolerance of mycorrhizal plants in the future.

3.
Microorganisms ; 12(3)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38543666

RESUMEN

Arthrobotrys oligospora, a widespread nematode-trapping fungus which can produce conidia for asexual reproduction and form trapping devices (traps) to catch nematodes. However, little is known about the sporulation mechanism of A. oligospora. This research characterized the functions and regulatory roles of the upstream spore-producing regulatory genes, AosfgA and AofluG, in A. oligospora. Our analysis showed that AosfgA and AofluG interacted with each other. Meanwhile, the AofluG gene was downregulated in the ΔAosfgA mutant strain, indicating that AosfgA positively regulates AofluG. Loss of the AosfgA and AofluG genes led to shorter hyphae and more septa, and the ΔAosfgA strain responded to heat and chemical stresses. Surprisingly, the number of nuclei was increased in the mycelia but reduced in the conidia of the ΔAosfgA and ΔAofluG mutants. In addition, after nematode induction, the number and volume of vacuoles were remarkably increased in the ΔAosfgA and ΔAofluG mutant strains. The abundance of metabolites was markedly decreased in the ΔAosfgA and ΔAofluG mutant strains. Collectively, the AosfgA and AofluG genes play critical roles in mycelial development, and they are also involved in vacuole assembly, the stress response, and secondary metabolism. Our study provides distinct insights into the regulatory mechanism of sporulation in nematode-trapping fungi.

4.
Front Bioeng Biotechnol ; 12: 1350227, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38456007

RESUMEN

Fibula transplantation plays an irreplaceable role in restoring the function and morphology of the defected mandible. However, the complex load-bearing environment of the mandible makes it urgent to accurately reconstruct the mandible, ensure the position of the condyle after surgery, and restore the patient's occlusal function and contour. The intervention of digital design and three-dimensional (3D) printed titanium mesh provides a more efficient method and idea to solve this problem. Digital design guides the accurate positioning, osteotomy, and simultaneous implant placement during surgery, and 3D printed titanium mesh ensures stable condyle position after surgery, restoring good mandibular function. The double-layer folded fibula maintains the vertical height of the mandible and a good facial contour, and simultaneous implant placement can establish a good occlusal relationship. This study conducted a retrospective analysis of five patients with jaw defects who underwent digital fibula reconstruction over the past 3 years. It was found that the surgical protocol combining digital design, 3D printed intraoperative guides, 3D printed titanium mesh, free fibula flap, immediate implant, and occlusal reconstruction to repair jaw defects had more ideal facial appearance and biological function. It will provide a more reliable surgical protocol for clinical management of large mandibular defects.

5.
Front Bioeng Biotechnol ; 12: 1343294, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38333080

RESUMEN

Polyetheretherketone (PEEK) has been one of the most promising materials in bone tissue engineering in recent years, with characteristics such as biosafety, corrosion resistance, and wear resistance. However, the weak bioactivity of PEEK leads to its poor integration with bone tissues, restricting its application in biomedical fields. This research effectively fabricated composite porous scaffolds using a combination of PEEK, nano-hydroxyapatite (nHA), and carbon fiber (CF) by the process of fused deposition molding (FDM). The experimental study aimed to assess the impact of varying concentrations of nHA and CF on the biological performance of scaffolds. The incorporation of 10% CF has been shown to enhance the overall mechanical characteristics of composite PEEK scaffolds, including increased tensile strength and improved mechanical strength. Additionally, the addition of 20% nHA resulted in a significant increase in the surface roughness of the scaffolds. The high hydrophilicity of the PEEK composite scaffolds facilitated the in vitro inoculation of MC3T3-E1 cells. The findings of the study demonstrated that the inclusion of 20% nHA and 10% CF in the scaffolds resulted in improved cell attachment and proliferation compared to other scaffolds. This suggests that the incorporation of 20% nHA and 10% CF positively influenced the properties of the scaffolds, potentially facilitating bone regeneration. In vitro biocompatibility experiments showed that PEEK composite scaffolds have good biosafety. The investigation on osteoblast differentiation revealed that the intensity of calcium nodule staining intensified, along with an increase in the expression of osteoblast transcription factors and alkaline phosphatase activities. These findings suggest that scaffolds containing 20% nHA and 10% CF have favorable properties for bone induction. Hence, the integration of porous PEEK composite scaffolds with nHA and CF presents a promising avenue for the restoration of bone defects using materials in the field of bone tissue engineering.

6.
Microbiol Res ; 280: 127573, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38103468

RESUMEN

Rab GTPases regulate vesicle trafficking in organisms and play crucial roles in growth and development. Arthrobotrys oligospora is a ubiquitous nematode-trapping (NT) fungus, it can form elaborate traps to capture nematodes. Our previous study found that deletion of Aorab7A abolished the trap formation and sporulation. Here, we investigated the regulatory mechanism of AoRab7A using transcriptomic, biochemical, and phenotypic comparisons. Transcriptome analysis, yeast library screening, and yeast two-hybrid assay identified two vacuolar protein sorting (Vps) proteins, AoVps41 and AoVps35, as putative targets of AoRab7A. The deletion of Aovps41 and Aovps35 caused considerable defects in multiple phenotypic traits, such as conidiation and trap formation. We further found a close connection between AoRab7A and Vps proteins in vesicle-vacuole fusion, which triggered vacuolar fragmentation. Further transcriptome analysis showed that AoRab7A and AoVps35 play essential roles in many cellular processes and components including proteasomes, autophagy, fatty acid degradation, and ribosomes in A. oligospora. Furthermore, we verified that AoRab7A, AoVps41, and AoVps35 are involved in ribosome and proteasome functions. The absence of these proteins inhibited the biosynthesis of nascent proteins and enhanced ubiquitination. Our findings suggest that AoRab7A interacts with AoVps41 and AoVps35 to mediate vacuolar fusion and influence lipid droplet accumulation, autophagy, and stress response. These proteins are especially required for the conidiation and trap development of A. oligospora.


Asunto(s)
Ascomicetos , Nematodos , Complejo de la Endopetidasa Proteasomal , Animales , Vacuolas , Saccharomyces cerevisiae , Ribosomas
7.
Cancer Lett ; 582: 216569, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38101608

RESUMEN

Progression occurs in approximately two-thirds of patients with locally advanced non-small cell lung cancer (LA-NSCLC) receiving chemoradiation and consolidation immunotherapy. Molecular indicators for outcome prediction are under development. A novel metric, the ratio of mean to max variant allele frequency (mmVAF), was derived from 431 pre-treatment tissue biopsies from The Cancer Genome Atlas and evaluated in serial circulating tumor DNA (ctDNA) from 70 LA-NSCLC patients receiving definitive radiotherapy/chemoradiotherapy (RT/CRT) with/without immunotherapy. High mmVAFs in pre-treatment tissue biopsies, indicating clonal predominant tumors (P < 0.01), were associated with inferior overall survival [OS, hazard ratio (HR): 1.48, 95 % confidence interval (CI): 1.11-1.98]. Similar associations of mmVAF with clonality (P < 0.01) and OS (HR: 2.24, 95 % CI: 0.71-7.08) were observed in pre-treatment ctDNA. At 1-month post-RT, ctDNA mmVAF-high patients receiving consolidation immunotherapy exhibited improved progression-free survival (PFS) compared to those who did not (HR: 0.14, 95 % CI: 0.03-0.67). From the baseline to week 4 of RT and/or 1-month post-RT, survival benefits from consolidation immunotherapy were exclusively observed in ctDNA mmVAF-increased patients (PFS, HR: 0.39, 95 % CI: 0.14-1.15), especially in terms of distant metastasis (HR: 0.11, 95 % CI: 0.01-0.95). In summary, our longitudinal data demonstrated the applicability of ctDNA-defined clonality for prognostic stratification and immunotherapy benefit prediction in LA-NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamiento farmacológico , Pronóstico , Quimioradioterapia , Inmunoterapia
8.
J Thorac Dis ; 15(11): 6106-6114, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38090297

RESUMEN

Background: Increasing evidence suggests that ground-glass opacity featured lung adenocarcinoma (GGO-LUAD) and pure solid-LUAD have significantly different tumor biological behaviors; the former is usually indolent. Genetic variations fundamentally contribute to this distinct tumor behaviors. This study aims to investigate and compare the gene mutations using next-generation sequencing (NGS) technology in these two subtypes of LUAD. Methods: The clinical data and gene testing results of 46 patients suffering from LUAD with a histologically invasive subtype ≤3 cm and operated in the Thoracic Surgery Department of Beijing Tsinghua Changgung Hospital from May 2019 to December 2022 were retrospectively analyzed; a case-control study was performed to compare the pathological and genetic differences between LUAD with a GGO component and pure solid-LUAD. Results: Notable differences existed in vascular invasion, tumor spread through air spaces (STAS) and high-risk histological subtypes (micropapillary or solid subtypes) between the two types of LUAD with similar histologically invasive size. No significant difference was found in the mutation frequency of EGFR and KRAS. However, gene mutations were more prevalent in the cell cycle and TP53 signaling pathway for solid-LUAD. A significant difference was found in the mutation frequency of the tumor suppressor genes TP53 and CDKN2A between the two types. Conclusions: The wild-type TP53 and CDKN2A genes could potentially be used as molecular indicators for indolent LUAD characterized by GGO-featured.

9.
J Alzheimers Dis Rep ; 7(1): 1351-1370, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38143774

RESUMEN

Background: The relationship between alpha 2-macroglobulin (A2M) gene and Alzheimer's disease (AD) has been widely studied across populations; however, the results are inconsistent. Objective: This study aimed to evaluate the association of A2M gene with AD by the application of meta-analysis. Methods: Relevant studies were identified by comprehensive searches. The quality of each study was assessed using the Newcastle-Ottawa Scale. Allele and genotype frequencies were extracted from each of the included studies. Odds ratio (OR) with corresponding 95% confidence intervals (CI) was calculated using a random-effects or fixed-effects model. The Cochran Q statistic and I2 metric was used to evaluate heterogeneity, and Egger's test and Funnel plot were used to assess publication bias. Results: A total of 62 studies were identified and included in the current meta-analysis. The G allele of rs226380 reduced AD risk (OR: 0.64, 95% CI: 0.47-0.87, pFDR = 0.012), but carrier with the TT genotype was more likely to develop AD in Asian populations (OR: 1.56, 95% CI: 1.12-2.19, pFDR = 0.0135). The V allele of the A2M-I/V (rs669) increased susceptibility to AD in female population (OR, 95% CI: 2.15, 1.38-3.35, pFDR = 0.0024); however, the II genotype could be a protective factor in these populations (OR, 95% CI: 0.43, 0.26-0.73, pFDR = 0.003). Sensitivity analyses confirmed the reliability of the original results. Conclusions: Existing evidence indicate that A2M single nucleotide polymorphisms (SNPs) may be associated with AD risk in sub-populations. Future studies with larger sample sizes will be necessary to confirm the results.

10.
Int J Med Sci ; 20(10): 1282-1292, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37786447

RESUMEN

Rabies continues to be a huge threat to public health. The rabies virus envelope glycoprotein (RABV G) is a major rabies virus antigen and contains neutralizing epitopes, which are primary candidates for subunit vaccines and diagnostic antigens. However, the production and purification of rRABV G while retaining its antigenic and immunogenic remains to be a challenge. Here, we aimed to establish a platform for rRABV G production and purification, and determine the immunogenicity and antigenicity of rRABV G. The cDNA fragment encoding the soluble form of RABV G was synthesized and cloned into a lentiviral expressing vector. Recombinant lentiviral vector LV-CMV-RABV G-eGFP was packaged, titered, and then transduced into HEK 293T cells. The cell culture supernatant was purified using nickel affinity chromatography and subsequently confirmed through Western Blot analysis and indirect enzyme-linked immunosorbent assay (ELISA). The ELISA utilized human sera obtained from individuals who had been vaccinated with the human commercial Purified Vero Cells Rabies Vaccine (PVRV). Notably, we observed a neutralizing antibody response in immunized pigs rather than in mice. This discrepancy could potentially be attributed to factors such as the instability of the rRABV G protein, variations in host responses, and variances in the adjuvant used. Taking all these findings into account, the rRABV G protein generated in this study exhibits promise as a potential vaccine candidate for the prevention of rabies.


Asunto(s)
Vacunas Antirrábicas , Virus de la Rabia , Rabia , Chlorocebus aethiops , Humanos , Animales , Ratones , Porcinos , Virus de la Rabia/genética , Rabia/prevención & control , Células HEK293 , Células Vero , Anticuerpos Antivirales , Glicoproteínas/genética , Vacunas Antirrábicas/genética , Proteínas del Envoltorio Viral/genética , Proteínas Recombinantes
11.
Appl Environ Microbiol ; 89(9): e0098323, 2023 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-37655869

RESUMEN

The asexual sporulation of filamentous fungi is an important mechanism for their reproduction, survival, and pathogenicity. In Aspergillus and several filamentous fungi, BrlA, AbaA, and WetA are the key elements of a central regulatory pathway controlling conidiation, and MedA is a developmental modifier that regulates temporal expression of central regulatory genes; however, their roles are largely unknown in nematode-trapping (NT) fungi. Arthrobotrys oligospora is a representative NT fungus, which can capture nematodes by producing adhesive networks (traps). Here, we characterized the function of AoMedA and three central developmental regulators (AoBrlA, AoAbaA, and AoWetA) in A. oligospora by gene disruption, phenotypic comparison, and multi-omics analyses, as these regulators are required for conidiation and play divergent roles in mycelial development, trap formation, lipid droplet accumulation, vacuole assembly, and secondary metabolism. A combined analysis of phenotypic traits and transcriptome showed that AoMedA and AoWetA are involved in the regulation of peroxisome, endocytosis, and autophagy. Moreover, yeast one-hybrid analysis showed that AoBrlA can regulate AoMedA, AoAbaA, and AoWetA, whereas AoMedA and AoAbaA can regulate AoWetA. Our results highlight the important roles of AoMedA, AoBrlA, AoAbaA, and AoWetA in conidiation, mycelia development, trap formation, and pathogenicity of A. oligospora and provide a basis for elucidating the relationship between conidiation and trap formation of NT fungi. IMPORTANCE Conidiation is the most common reproductive mode for many filamentous fungi and plays an essential role in the pathogenicity of fungal pathogens. Nematode-trapping (NT) fungi are a special group of filamentous fungi owing to their innate abilities to capture and digest nematodes by producing traps (trapping devices). Sporulation plays an important role in the growth and reproduction of NT fungi, and conidia are the basic components of biocontrol reagents for controlling diseases caused by plant-parasitic nematodes. Arthrobotrys oligospora is a well-known NT fungus and is a routinely used model fungus for probing the interaction between fungi and nematodes. In this study, the functions of four key regulators (AoMedA, AoBrlA, AoAbaA, and AoWetA) involved in conidiation were characterized in A. oligospora. A complex interaction between AoMedA and three central regulators was noted; these regulators are required for conidiation and trap formation and play a pleiotropic role in multiple intracellular activities. Our study first revealed the role of AoMedA and three central regulators in conidiation, trap formation, and pathogenicity of A. oligospora, which contributed to elucidating the regulatory mechanism of conidiation in NT fungi and helped in developing effective reagents for biocontrol of nematodes.


Asunto(s)
Ascomicetos , Nematodos , Animales , Metabolismo Secundario , Ascomicetos/fisiología , Saccharomyces cerevisiae
12.
iScience ; 26(8): 107404, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37609635

RESUMEN

Mitogen-activated protein kinase (MAPK) Fus3 is an essential regulator of cell differentiation and virulence in fungal pathogens of plants and animals. However, the function and regulatory mechanism of MAPK signaling in nematode-trapping (NT) fungi remain largely unknown. NT fungi can specialize in the formation of "traps", an important indicator of transition from a saprophytic to a predatory lifestyle. Here, we characterized an orthologous Fus3 in a typical NT fungus Arthrobotrys oligospora using multi-phenotypic analysis and multi-omics approaches. Our results showed that Fus3 plays an important role in asexual growth and development, conidiation, stress response, DNA damage, autophagy, and secondary metabolism. Importantly, Fus3 plays an indispensable role in hyphal fusion, trap morphogenesis, and nematode predation. Moreover, we constructed the regulatory networks of Fus3 by means of transcriptomic and yeast two-hybrid techniques. This study provides insights into the mechanism of MAPK signaling in asexual development and pathogenicity of NT fungi.

13.
Plants (Basel) ; 12(14)2023 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-37514211

RESUMEN

Arbuscular mycorrhizal fungi (AMF) and dark septate fungi (DSE) were simultaneously colonized in the root cells of maize. Single AMF and DSE symbiosis have been proven to improve the drought tolerance of maize. However, the effects of both fungi coexisting in maize roots under drought stress are not yet known. In this study, pot experiments of maize seedlings were conducted through four inoculation treatments (single AMF inoculation of Rhizophagus irregularis, single DSE inoculation of Exophiala pisciphila, co-inoculation of AMF + DSE and non-mycorrhizal inoculation) under well-watered (WW) and drought-stressed (DS) conditions. AMF and DSE colonization status, maize physiology and aquaporin gene expression in maize roots were investigated. The objective of this paper was to evaluate whether AMF and DSE had competitive, independent or synergistic effects on regulating the drought tolerance of maize. When maize seedlings of three inoculation treatments were subjected to drought stress, single AMF inoculation had the highest shoot and root dry weight, plant height, root length, osmotic root hydraulic conductivity and hydrostatic root hydraulic conductivity in maize seedlings. However, co-inoculation of AMF + DSE induced the highest stomatal conductance in maize leaves and the lowest H2O2 and O2•- concentration, membrane electrolyte leakage, intercellular CO2 concentration and gene expression level of ZmPIP1;1, ZmPIP1;2, ZmPIP2;1, ZmPIP2;5 and ZmPIP2;6. In addition, co-inoculation of AMF + DSE also obviously down-regulated the GintAQPF1 and GintAQPF2 expression in R. irregularis compared with single AMF inoculation treatment. Under DS stress, there were competitive relationships between AMF and DSE with regard to regulating mycorrhizal colonization, maize growth, root hydraulic conductivity and the gene expression of aquaporins in R. irregularis, but there were synergistic relationships with regard to regulating membrane electrolyte leakage, oxidative damage, photosynthesis and the aquaporin gene expression of maize seedlings. The obtained results improve our knowledge about how the mechanisms of AMF and DSE coexist, promoting the drought tolerance of host plants.

14.
Microorganisms ; 11(6)2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37375114

RESUMEN

Multidrug resistance (Mdr) proteins are critical proteins for maintenance of drug resistance in fungi. Mdr1 has been extensively studied in Candida albicans; its role in other fungi is largely unknown. In this study, we identified a homologous protein of Mdr (AoMdr1) in the nematode-trapping (NT) fungus Arthrobotrys oligospora. It was found that the deletion of Aomdr1 resulted in a significant reduction in the number of hyphal septa and nuclei as well as increased sensitivity to fluconazole and resistance to hyperosmotic stress and SDS. The deletion of Aomdr1 also led to a remarkable increase in the numbers of traps and mycelial loops in the traps. Notably, AoMdr1 was able to regulate mycelial fusion under low-nutrient conditions, but not under nutrient-rich conditions. AoMdr1 was also involved in secondary metabolism, and its deletion caused an increase in arthrobotrisins (specific compounds produced by NT fungi). These results suggest that AoMdr1 plays a crucial role in the fluconazole resistance, mycelial fusion, conidiation, trap formation, and secondary metabolism of A. oligospora. Our study contributes to the understanding of the critical role of Mdr proteins in mycelial growth and the development of NT fungi.

15.
J Fungi (Basel) ; 9(4)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37108952

RESUMEN

Malate dehydrogenase (MDH) is a key enzyme in the tricarboxylic acid (TCA) cycle and is essential for energy balance, growth, and tolerance to cold and salt stresses in plants. However, the role of MDH in filamentous fungi is still largely unknown. In this study, we characterized an ortholog of MDH (AoMae1) in a representative nematode-trapping (NT) fungus Arthrobotrys oligospora via gene disruption, phenotypic analysis, and nontargeted metabolomics. We found that the loss of Aomae1 led to a weakening of MDH activity and ATP content, a remarkable decrease in conidia yield, and a considerable increase in the number of traps and mycelial loops. In addition, the absence of Aomae1 also caused an obvious reduction in the number of septa and nuclei. In particular, AoMae1 regulates hyphal fusion under low nutrient conditions but not in nutrient-rich conditions, and the volumes and sizes of the lipid droplets dynamically changed during trap formation and nematode predation. AoMae1 is also involved in the regulation of secondary metabolites such as arthrobotrisins. These results suggest that Aomae1 has an important role in hyphal fusion, sporulation, energy production, trap formation, and pathogenicity in A. oligospora. Our results enhance the understanding of the crucial role that enzymes involved in the TCA cycle play in the growth, development, and pathogenicity of NT fungi.

16.
Dent Mater J ; 42(4): 461-468, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37032105

RESUMEN

This study investigated the effects of nonthermal Ar/O2 plasma on the osseointegration of titanium implants. Through 8 weeks' in vivo evaluation of implants inserted into femoral bones of male Sprague-Dawley rats, the new bone mineralization apposition rate (MAR) is increased by 1.87 and 2.14 times for implants of smooth machined (SM) and sand-blasted and acid-etched (SLA) after plasma treatment. The bone volume fraction (bone volume/total volume, BV/TV) and bone-implant contact (BIC) ratios are improved by 1.31, 1.26 times and 1.35, 1.15 times after 90 s plasma treatment. The improved hydrophilicity rather than implant surface morphology is believed to play a critical role for the osseointegration improvement.


Asunto(s)
Implantes Dentales , Oseointegración , Ratas , Animales , Masculino , Propiedades de Superficie , Ratas Sprague-Dawley , Implantación Dental Endoósea , Titanio/farmacología
17.
Front Psychol ; 14: 1064632, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36910770

RESUMEN

The novel coronavirus (COVID-19) has inflicted unprecedented damage on the tourism industry. However, the psychological health fallout of COVID-19 on tour guides has not received empirical attention yet. Therefore, the present study aims to examine how psychological capital (PsyCap) improve tour guides' psychological wellbeing (PWB), the mediating effects of work-family conflict (WFC), family-work conflict (FWC), work-family facilitation (WFF) and family-work facilitation (FWF), and the moderating effect of perceived organizational support (POS). For this quantitative research, the data were collected from 276 tour guides in China. The results indicate that PsyCap significantly mitigates two directions of work-family conflict and intensifies two directions of work-family facilitation in order to promote tour guides' PWB. Furthermore, POS moderates the direct effects of two directions of conflict and facilitation on PWB and also moderates the indirect effects of PsyCap on the aforesaid outcome via two directions of conflict and facilitation. Theoretical and practical implications, limitations and future research directions are provided.

18.
Microbiol Spectr ; : e0395722, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36786575

RESUMEN

Nematode-trapping (NT) fungi are a unique group of carnivorous microorganisms that can capture and digest nematodes by producing ingenious trapping devices (traps). Arthrobotrys oligospora, a representative NT fungus, can develop adhesive three-dimensional networks for nematode predation. Hyphal fusion is indispensable for the trap formation of A. oligospora. Here, we characterized an orthologous Ste12 protein (AoSte12) in A. oligospora via gene disruption, DNA affinity purification sequencing (DAP-Seq), and multi-omics approaches. The disruption of the Aoste12 gene caused an increase in hyphal fusion and resulted in defects in mycelial growth, conidiation, trap morphology, and stress resistance, as well as reducing the number of nuclei and lipid droplet accumulation. Moreover, transcriptome and DAP-Seq analysis revealed that AoSte12 was involved in cellular processes associated with growth, cell fusion, the tricarboxylic acid cycle, vesicles, actin filaments, and lipid metabolism. In addition, combining metabolome with transcriptome and DAP-Seq analysis indicated that AoSte12 was involved in the mitogen-activated protein kinase signaling pathway, lipid metabolism, and secondary metabolites. A yeast two-hybrid assay revealed that AoSte12 can interact with diverse proteins, such as the MAK-2 orthologue protein Fus3, the vacuolar sorting protein Pep3, and UDP-glycosyltransferase. Our results suggest that AoSte12 plays an indispensable role in hyphal fusion and thus regulates sporulation and trap morphogenesis. These results provide deep insights into the connection between hyphal fusion and trap formation in NT fungi. IMPORTANCE Nematode-trapping (NT) fungi are an important natural enemy of nematodes and can capture their prey by producing traps. Hyphal anastomosis and fusion are important for mycelial growth and the colony morphological development of filamentous fungi and are also crucial for the trap morphogenesis of NT fungi. Arthrobotrys oligospora can form complex three-dimensional networks (traps) when sensing the presence of nematodes. This study revealed that AoSte12 is indispensable for hyphal fusion and that it regulates mycelial growth, conidiation, trap morphogenesis, stress resistance, the number of nuclei, and lipid droplet accumulation in A. oligospora. In addition, DNA affinity purification sequencing, transcriptome, and metabolome analyses further revealed that AoSte12 is involved in the mitogen-activated protein kinase pathway, lipid metabolism, and secondary metabolism. Overall, these findings expand the important role of AoSte12 in NT fungus A. oligospora and provide a broad foundation for elucidating the regulatory mechanism of trap development and the lifestyle transitions of pathogenic fungi.

19.
mSphere ; 8(2): e0001223, 2023 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-36786584

RESUMEN

The peroxins encoded by PEX genes involved in peroxisome biogenesis play a crucial role in cellular metabolism and pathogenicity in fungi. Herein, we characterized a filamentous fungus-specific peroxin Pex14/17 in the Arthrobotrys oligospora, a representative species of nematode-trapping fungi. The deletion of AoPEX14/17 resulted in a remarkable reduction in mycelial growth, conidia yield, trap formation, and pathogenicity. Compared with the wild-type strain, the ΔAopex14/17 mutant exhibited more lipid droplet and reactive oxygen species accumulation accompanied with a significant decrease in fatty acid utilization and tolerance to oxidative stress. Transcriptomic analysis indicated that AoPEX14/17 was involved in the regulation of metabolism, genetic information processing, environmental information processing, and cellular processes. In subcellular morphology, the deletion of AoPEX14/17 resulted in a decrease in the number of cell nuclei, autophagosomes, and Woronin bodies. Metabolic profile analysis showed that AoPex14/17 affects the biosynthesis of secondary metabolites. Yeast two-hybrid assay revealed that AoPex14/17 interacted with AoPex14 but not with AoPex13. Taken together, our results suggest that Pex14/17 is the main factor for modulating growth, development, and pathogenicity in A. oligospora. IMPORTANCE Peroxisome biogenesis genes (PEX) play an important role in growth, development, and pathogenicity in pathogenic fungi. However, the roles of PEX genes remain largely unknown in nematode-trapping (NT) fungi. Here, we provide direct evidence that AoPex14/17 regulates mycelial growth, conidiation, trap formation, autophagy, endocytosis, catalase activity, stress response to oxidants, lipid metabolism, and reactive oxygen species production. Transcriptome analysis and metabolic profile suggested that AoPex14/17 is involved in multiple cellular processes and the regulation of secondary metabolism. Therefore, our study extends the functions of PEX genes, which helps to elucidate the mechanism of organelle development and trap formation in NT fungi and lays the foundation for the development of efficient nematode biocontrol agents.


Asunto(s)
Ascomicetos , Nematodos , Animales , Metabolismo Secundario , Especies Reactivas de Oxígeno/metabolismo , Nematodos/microbiología , Ascomicetos/genética
20.
Sensors (Basel) ; 23(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36772641

RESUMEN

Mobile edge computing (MEC) is a promising technique to support the emerging delay-sensitive and compute-intensive applications for user equipment (UE) by means of computation offloading. However, designing a computation offloading algorithm for the MEC network to meet the restrictive requirements towards system latency and energy consumption remains challenging. In this paper, we propose a joint user-association, task-partition, and resource-allocation (JUTAR) algorithm to solve the computation offloading problem. In particular, we first build an optimization function for the computation offloading problem. Then, we utilize the user association and smooth approximation to simplify the objective function. Finally, we employ the particle swarm algorithm (PSA) to find the optimal solution. The proposed JUTAR algorithm achieves a better system performance compared with the state-of-the-art (SOA) computation offloading algorithm due to the joint optimization of the user association, task partition, and resource allocation for computation offloading. Numerical results show that, compared with the SOA algorithm, the proposed JUTAR achieves about 21% system performance gain in the MEC network with 100 pieces of UE.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA