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1.
J Neurophysiol ; 132(3): 744-756, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39015075

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disease, and mild cognitive impairment (MCI) is considered a transitional stage between healthy aging and dementia. Early detection of MCI can help slow down the progression of AD. At present, there are few studies exploring the characteristics of abnormal dynamic brain activity in AD. This article uses a method called leading eigenvector dynamics analysis (LEiDA) to study resting-state functional magnetic resonance imaging (rs-fMRI) data of AD, MCI, and cognitively normal (CN) participants. By identifying repetitive states of phase coherence, intergroup differences in brain dynamic activity indicators are examined, and the neurobehavioral scales were used to assess the relationship between abnormal dynamic activities and cognitive function. The results showed that in the indicators of occurrence probability and lifetime, the globally synchronized state of the patient group decreased. The activity state of the limbic regions significantly detected the difference between AD and the other two groups. Compared to CN, AD and MCI have varying degrees of increase in default and visual region activity states. In addition, in the analysis related to the cognitive scales, it was found that individuals with poorer cognitive abilities were less active in the globally synchronized state and more active in limbic region activity state and visual region activity state. Taken together, these findings reveal abnormal dynamic activity of resting-state networks in patients with AD and MCI, provide new insights into the dynamic analysis of brain networks, and contribute to a deeper understanding of abnormal spatial dynamic patterns in AD patients.NEW & NOTEWORTHY Alzheimer's disease (AD) is a neurodegenerative disease, but few studies have explored the characteristics of abnormal dynamic brain activity in AD patients. Here, our report reveals the abnormal dynamic activity of the patients' resting-state network, providing new insights into the dynamic analysis of brain networks and helping to gain a deeper understanding of the abnormal spatial dynamic patterns in AD patients.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Imagen por Resonancia Magnética , Red Nerviosa , Humanos , Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/diagnóstico por imagen , Femenino , Anciano , Masculino , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/diagnóstico por imagen , Red Nerviosa/fisiopatología , Red Nerviosa/diagnóstico por imagen , Persona de Mediana Edad , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Descanso , Anciano de 80 o más Años
2.
Anal Chem ; 96(37): 14759-14765, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39234645

RESUMEN

Regulating photocurrent polarity is highly attractive for fabricating photoelectrochemical (PEC) biosensors with improved sensitivity and accuracy in practical samples. Here, a new approach that adopts the in situ generated AgI precipitate and AgNCs to reversal Bi2WO6 polarity with formation of Z-type heterojunction was proposed for the first time, which coupled with a high-efficient target conversion strategy of exonuclease III (Exo III)-assisted triple recycling amplification for sensing miRNA-21. The target-related DNA nanospheres in situ generated on electrode with loading of plentiful AgI and AgNCs not only endowed the photocurrent of Bi2WO6 switching from the anodic to cathodic one due to the changes in the electron transfer pathway but also formed AgI/AgNCs/Au/Bi2WO6 Z-type heterojunction to improve the photoelectric conversion efficiency for acquiring extremely enhanced PEC signal, thereby significantly avoiding the problem of high background signal derived from traditional unidirectional increasing/decreasing response and false-positive/false-negative. Experimental data showed that the PEC biosensor had a low detection limit down to 0.085 fM, providing a new polarity-reversal mechanism and expected application in diverse fields, including biomedical research and clinical diagnosis.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , MicroARNs , Compuestos de Plata , MicroARNs/análisis , Compuestos de Plata/química , Procesos Fotoquímicos , Exodesoxirribonucleasas/química , Exodesoxirribonucleasas/metabolismo , Límite de Detección , Humanos , Electrodos , Yoduros
3.
New Phytol ; 237(1): 279-294, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36177721

RESUMEN

Nitrogen (N) enrichment poses threats to biodiversity and ecosystem stability, while arbuscular mycorrhizal (AM) fungi play important roles in ecosystem stability and functioning. However, the ecological impacts, especially thresholds of N enrichment potentially causing AM fungal community shifts have not been adequately characterized. Based on a long-term field experiment with nine N addition levels ranging from 0 to 50 g N m-2 yr-1 in a temperate grassland, we characterized the community response patterns of AM fungi to N enrichment. Arbuscular mycorrhizal fungal biomass continuously decreased with increasing N addition levels. However, AM fungal diversity did not significantly change below 20 g N m-2 yr-1 , but dramatically decreased at higher N levels, which drove the AM fungal community to a potentially unstable state. Structural equation modeling showed that the decline in AM fungal biomass could be well explained by soil acidification, whereas key driving factors for AM fungal diversity shifted from soil nitrogen : phosphorus (N : P) ratio to soil pH with increasing N levels. Different aspects of AM fungal communities (biomass, diversity and community composition) respond differently to increasing N addition levels. Thresholds for substantial community shifts in response to N enrichment in this grassland ecosystem are identified.


Asunto(s)
Micobioma , Micorrizas , Micorrizas/fisiología , Nitrógeno , Ecosistema , Pradera , Microbiología del Suelo , Suelo/química , China
4.
Fish Shellfish Immunol ; 135: 108659, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36868535

RESUMEN

Vibrio mimicus (V. mimicus) is a pathogenic bacterium that causes diseases in humans and various aquatic animals. A particularly efficient way to provide protection against V. mimicus is through vaccination. However, there are few commercial vaccines against V. mimics, especially oral vaccines. In our study, two surface-display recombinant Lactobacillus casei (L. casei) Lc-pPG-OmpK and Lc-pPG-OmpK-CTB were constructed using L. casei ATCC393 as an antigen delivery vector, outer membrane protein K (OmpK) of V. mimicus as an antigen, and cholera toxin B subunit (CTB) as a molecular adjuvant; furthermore, the immunological effects of recombinant L.casei in Carassius auratus (C. auratus) were assessed. The results indicated that oral recombinant L.casei Lc-pPG-OmpK and Lc-pPG-OmpK-CTB stimulated higher levels of serum-specific immunoglobulin M (IgM) and increased the activity of acid phosphatase (ACP), alkaline phosphatase (AKP), superoxide dismutase (SOD), lysozyme (LYS), lectin, C3, and C4 in C. auratus, compared with control groups (Lc-pPG group and PBS group). Furthermore, the expression of interleukin-1ß (IL-1ß), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), and transforming growth factor-ß (TGF-ß) in the liver, spleen, head kidney, hind intestine and gills of C. auratus was significantly increased, compared with that in the controls. These results demonstrated that the two recombinant L. casei strains could effectively trigger humoral and cellular immunity in C. auratus. In addition, two recombinant L.casei strains were able to survive and colonize the intestine of C. auratus. Importantly, after being challenged with V. mimicus, C. auratus fed Lc-pPG-OmpK and Lc-pPG-OmpK-CTB exhibited greater survival rates than the controls (52.08% and 58.33%, respectively). The data showed that recombinant L. casei could elicit a protective immunological response in C. auratus. The effect of the Lc-pPG-OmpK-CTB group was better than that of the Lc-pPG-OmpK group, and Lc-pPG-OmpK-CTB was found to be an effective candidate for oral vaccination.


Asunto(s)
Lacticaseibacillus casei , Vibrio mimicus , Humanos , Animales , Lacticaseibacillus casei/genética , Carpa Dorada , Vacunación , Adyuvantes Inmunológicos , Proteínas Recombinantes
5.
J Environ Manage ; 348: 119335, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37857212

RESUMEN

Addressing the widespread concern of chromium (Cr) pollution, this study investigated its impacts on bacterial communities across eight soil types, alongside the potential Cr transformation-related genes. Utilizing real-time PCR, 16S rRNA gene sequencing and gene prediction, we revealed shifts in bacterial community structure and function at three Cr exposure levels. Our results showed that the bacterial abundance in all eight soil types was influenced by Cr to varying extents, with yellow‒brown soil being the most sensitive. The bacterial community composition of different soil types exhibited diverse responses to Cr, with only the relative abundance of Proteobacteria decreasing with increasing Cr concentration across all soil types. Beta diversity analysis revealed that while Cr concentration impacted the assembly process of bacterial communities to a certain extent, the influence on the compositional structure of bacterial communities was primarily driven by soil type rather than Cr concentration. The study also identified biomarkers for each soil type under three Cr levels, offering a basis for monitoring changes in Cr pollution. By predicting crucial functional genes related to Cr transformation, it was observed that the relative abundance of chrA (chromate transporter) in yellow‒brown soil significantly exceeded that in all other soil types, suggesting its potential for Cr adaptation. The study also revealed correlations among soil physicochemical properties, Cr concentration, and these functional genes, providing a foundation for future research aimed at more precise functional analysis and the development of effective soil remediation strategies.


Asunto(s)
Cromo , Contaminantes del Suelo , Cromo/análisis , Suelo/química , ARN Ribosómico 16S/genética , Bacterias/genética , Proteobacteria/genética , Microbiología del Suelo , Contaminantes del Suelo/análisis
6.
New Phytol ; 234(6): 2003-2017, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34449895

RESUMEN

Climate extremes pose enormous threats to natural ecosystems. Arbuscular mycorrhizal (AM) fungi are key plant symbionts that can affect plant community dynamics and ecosystem stability. However, knowledge about how AM fungal communities respond to climate extremes in natural ecosystems remains elusive. Based on a grassland extreme drought experiment in Inner Mongolia, we investigated the response of AM fungal communities to extreme drought in association with plant communities. The experiment simulated two types of extreme drought (chronic/intense) of once-in-20-year occurrence. AM fungal richness and community composition exhibited high sensitivity to extreme drought and were more sensitive to intense drought than chronic drought. This community sensitivity (i.e. decline in richness and shifts in community composition) of AM fungi can be jointly explained by soil moisture, plant richness, and aboveground productivity. Notably, the robustness of the plant-AM fungal community co-response increased with drought intensity. Our results indicate that AM fungal communities are sensitive to climate extremes, and we propose that the plant community mediates AM fungal community responses. Given the ubiquitous nature of AM associations, their climate sensitivity may have profound consequences on plant communities and ecosystem stability under climate change.


Asunto(s)
Micorrizas , Sequías , Ecosistema , Hongos , Pradera , Micorrizas/fisiología , Plantas/microbiología , Suelo , Microbiología del Suelo
7.
Microb Pathog ; 167: 105559, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35568093

RESUMEN

With the aim to discover novel lactic acid bacteria and Bacillus strains from fish as potential probiotics to replace antibiotics in aquaculture, the present study was conducted to isolate lactic acid bacteria and Bacillus from intestinal tract of healthy crucian carp (Carassiu auratus) and largemouth bass (Micropterus salmoides) and evaluate their resistance against Aeromonas veronii. Based on the evaluation of antibacterial activity and tolerance test, one strain of lactic acid bacteria (Weissella cibaria C-10) and one strain of Bacillus (Bacillus amyloliquefaciens T-5) with strong environmental stability were screened out. The safety evaluation showed that these two strains were non-toxic to crucian carp and were sensitive to most antibiotics. In vivo study, the crucian carps were fed a basal diet supplemented with W. cibaria C-10 (C-10), B. amyloliquefaciens T-5 (T-5) and W. cibaria C-10 + B. amyloliquefaciens T-5 (C-10+T-5), respectively, for 5 weeks. Then, various immune parameters were measured at 35 days of post-feeding. Results showed both probiotics could improve the activities of related immune enzymes, immune factors and non-specific immune antibodies in blood and organs (gill, gut, kidney, liver, and spleen) of crucian carp in varying degrees. Moreover, after 7 days of challenge experiment, the survival rates after challenged with A. veronii of W. cibaria C-10 (C-10), B. amyloliquefaciens T-5 (T-5) and W. cibaria C-10 + B. amyloliquefaciens T-5 (C-10+T-5) supplemented groups to the crucian carps were 20%, 33% and 22%, respectively. Overall, W. cibaria C-10 and B. amyloliquefaciens T-5 could be considered to be developed into microecological preparations for the alternatives of antibiotics in aquaculture.


Asunto(s)
Bacillus amyloliquefaciens , Bacillus , Carpas , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Probióticos , Aeromonas veronii , Animales , Antibacterianos/farmacología , Suplementos Dietéticos , Enfermedades de los Peces/microbiología , Infecciones por Bacterias Gramnegativas/prevención & control , Infecciones por Bacterias Gramnegativas/veterinaria , Weissella
8.
Cancer Cell Int ; 22(1): 214, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35706026

RESUMEN

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is the leading cause of cancer-related death worldwide with a poor prognosis. Given that DEPDC1B plays a key role in multiple cancers, the role of this molecule in ESCC was explored to identify potential targets for ESCC patients. METHOD: The expression level of DEPDC1B in ESCC was revealed based on the TCGA database and immunohistochemical experiments on clinical tissues. The correlation between DEPDC1B and survival of ESCC patients was analyzed by Kaplan-Meier method. Small hairpin RNA (shRNA)-mediated silencing of DEPDC1B expression in ESCC cells and performed a series of in vitro and in vivo functional validations. RESULT: DEPDC1B was overexpressed in ESCC. High expression of DEPDC1B was significantly negatively correlated with overall survival in patients with ESCC. Moreover, knockdown of DEPDC1B inhibited ESCC cell proliferation, clone formation, migration, tumor formation and promoted apoptosis. Furthermore, knockdown of DEPDC1B leaded to significant downregulation of GABRD in ESCC cells. Meanwhile, GABRD expression was upregulated in ESCC, and its silencing can inhibit the proliferation and migration of the tumor cells. Interestingly, there was a protein interaction between DEPDC1B and GABRD. Functionally, GABRD knockdown partially reversed the contribution of DEPDC1B to ESCC progression. In addition, GABRD regulated ESCC progression may depend on PI3K/AKT/mTOR signaling pathway. CONCLUSION: DEPDC1B collaborated with GABRD to regulate ESCC progression, and inhibition of this signaling axis may be a potential therapeutic target for ESCC.

9.
Mycorrhiza ; 32(1): 33-43, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34981189

RESUMEN

Enriched surface ozone (O3) can impose harmful effects on plants. Conversely, arbuscular mycorrhizal (AM) symbiosis can enhance plant tolerance to various environmental stresses and facilitate plant growth. The interaction of AM fungi and O3 on plant performance, however, seldom has been investigated. In this study, alfalfa (Medicago sativa L.) was used as a test plant to study the effects of O3 and AM symbiosis on plant physiology and growth under two O3 levels (ambient air and elevated O3 with 60 nmol·mol-1 O3 enrichment) and three AM inoculation treatments (inoculation with exogenous or indigenous AM fungi and non-inoculation control). The results showed that elevated O3 decreased plant net photosynthetic rate and biomass, and increased malondialdehyde concentration, while AM inoculation (with both exogenous and indigenous AM fungi) could promote plant nutrient acquisition and growth irrespective of O3 levels. The positive effects of AM symbiosis on plant nutrient acquisition and antioxidant enzyme (superoxide dismutase and peroxidase) activities were most likely offset by increased stomatal conductance and O3 intake. As a result, AM inoculation and O3 generally showed no significant interactions on plant performance: although elevated O3 did not diminish the beneficial effects of AM symbiosis on alfalfa plants, AM symbiosis also did not alleviate the harmful effects of O3 on plants.


Asunto(s)
Micorrizas , Ozono , Medicago sativa , Micorrizas/química , Ozono/análisis , Ozono/farmacología , Fósforo , Raíces de Plantas/química , Suelo , Simbiosis
10.
Mycorrhiza ; 28(3): 285-300, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29455337

RESUMEN

Liquorice (Glycyrrhiza uralensis) is an important medicinal plant for which there is a huge market demand. It has been reported that arbuscular mycorrhizal (AM) symbiosis and drought stress can stimulate the accumulation of the active ingredients, glycyrrhizin and liquiritin, in liquorice plants, but the potential interactions of AM symbiosis and drought stress remain largely unknown. In the present work, we investigated mycorrhizal effects on plant growth and accumulation of glycyrrhizin and liquiritin in liquorice plants under different water regimes. The results indicated that AM plants generally exhibited better growth and physiological status including stomatal conductance, photosynthesis rate, and water use efficiency compared with non-AM plants. AM inoculation up-regulated the expression of an aquaporin gene PIP and decreased root abscisic acid (ABA) concentrations under drought stress. In general, AM plants displayed lower root carbon (C) and nitrogen (N) concentrations, higher phosphorus (P) concentrations, and therefore, lower C:P and N:P ratios but higher C:N ratio than non-AM plants. On the other hand, AM inoculation increased root glycyrrhizin and liquiritin concentrations, and the mycorrhizal effects were more pronounced under moderate drought stress than under well-watered condition or severe drought stress for glycyrrhizin accumulation. The accumulation of glycyrrhizin and liquiritin in AM plants was consistent with the C:N ratio changes in support of the carbon-nutrient balance hypothesis. Moreover, the glycyrrhizin accumulation was positively correlated with the expression of glycyrrhizin biosynthesis genes SQS1, ß-AS, CYP88D6, and CYP72A154. By contrast, no significant interaction of AM inoculation with water treatment was observed for liquiritin accumulation, while we similarly observed a positive correlation between liquiritin accumulation and the expression of a liquiritin biosynthesis gene CHS. These results suggested that AM inoculation in combination with proper water management potentially could improve glycyrrhizin and liquiritin accumulation in liquorice roots and may be practiced to promote liquorice cultivation.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Glomeromycota/fisiología , Glycyrrhiza uralensis/microbiología , Glycyrrhiza uralensis/fisiología , Micorrizas/fisiología , Sequías , Flavanonas/metabolismo , Glucósidos/metabolismo , Glycyrrhiza uralensis/genética , Glycyrrhiza uralensis/crecimiento & desarrollo , Ácido Glicirrínico/metabolismo , Minerales/metabolismo , Fotosíntesis , Estrés Fisiológico/fisiología
11.
J Environ Manage ; 191: 244-251, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28113066

RESUMEN

In this study, the transformation of dissolved organic matter (DOM) in nanofiltration concentrated leachate during three ozone-based oxidation processes (i.e., O3, O3/H2O2 and O3/UV) was investigated. The transformation characteristics of DOM were evaluated by gel filtration chromatography (GFC), XAD-8 resin fractionation, excitation-emission matrix fluorescence spectroscopy (EEM) and Fourier transform infrared spectroscopy (FTIR). Compared with O3-alone process, the removal efficiencies of COD, TOC, and color were improved in O3-combined processes (i.e., O3/H2O2 and O3/UV) approximately by 10-15%, 7-15%, and 15-20%, respectively. Humic acid (HA) was completely degraded and preferentially reacted with the oxidants during ozonation processes. HA was first converted into fulvic acid (FA), and then the majority of these intermediates were further converted to hydrophilic fraction (HyI). The GFC results indicated that the broader molecular weight distribution of DOM was observed, and high molecular weight DOM (i.e., 0.45 µm-100 kDa) was successfully converted to low molecular weight organics in the range of 1-10 kDa after ozonation reactions. The EEM spectra also showed that HA and FA were effectively converted into HyI after ozonation for 90 min. It is suggested that ozone-based oxidation processes could effectively change the DOM distribution and fluorescence features of concentrated leachate.


Asunto(s)
Peróxido de Hidrógeno/química , Ozono/química , Cromatografía en Gel , Sustancias Húmicas , Oxidación-Reducción
12.
Microb Ecol ; 72(2): 418-27, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27117797

RESUMEN

The physiological tolerance hypothesis (PTH) postulates that it is the tolerance of species to climatic factors that determines overall community richness. Here, we tested whether a group of mutualistic microbes, Glomeromycota, is distributed in semi-arid environments in ways congruent with the PTH. For this purpose, we modeled with climatic predictors the niche of each of the four orders of Glomeromycota and identified predictors of arbuscular mycorrhizal (AM) fungal operational taxonomic unit (OTU) richness. Our dataset consisted of 50 paired grassland and farmland sites in the farming-pastoral ecotone of northern China. We observed shifts in the relative abundance of AM fungal orders in response to climatic variables but also declines in OTU richness in grassland sites that had experienced high precipitation during the preceding year which was incongruous with the PTH. We found pronounced differences across groups of Glomeromycotan fungi in their responses to climatic variables and identified strong dependencies of AM fungal communities on precipitation. Given that precipitation is expected to further decline in the farming-pastoral ecotone over the coming years and that mycorrhiza represents an integral constituent of ecosystem functioning, it is likely that the ecosystem services in the region will change accordingly.


Asunto(s)
Clima , Glomeromycota/clasificación , Micorrizas/clasificación , Simbiosis , China , Glomeromycota/aislamiento & purificación , Pradera , Micorrizas/aislamiento & purificación , Microbiología del Suelo , Estrés Fisiológico , Temperatura
13.
Mycorrhiza ; 26(8): 879-893, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27456042

RESUMEN

Arbuscular mycorrhizal (AM) symbiosis is known to stimulate plant drought tolerance. However, the mechanisms underlying the synergistic responses of the symbiotic partners to drought stress are largely unknown. A split-root experiment was designed to investigate the molecular interactions between a host plant and an AM fungus (AMF) under drought stress. In the two-compartment cultivation system, an entire or only a half root system of a maize plant was inoculated with an AMF, Rhizophagus intraradices, in the presence of localized or systemic drought treatment. Plant physiological parameters including growth, water status, and phosphorus concentration, and the expression of drought tolerance-related genes in both roots and R. intraradices were recorded. Although mycorrhizal inoculation in either one or both compartments systemically decreased abscisic acid (ABA) content in the whole root system subjected to systemic or local drought stress, we observed local and/or systemic AM effects on root physiological traits and the expression of functional genes in both roots and R. intraradices. Interestingly, the simultaneous increase in the expression of plant genes encoding D-myo-inositol-3-phosphate synthase (IPS) and 14-3-3-like protein GF14 (14-3GF), which were responsible for ABA signal transduction, was found to be involved in the activation of 14-3-3 protein and aquaporins (GintAQPF1 and GintAQPF2) in R. intraradices. These findings suggest that coexpression of IPS and 14-3GF is responsible for the crosstalk between maize and R. intraradices under drought stress, and potentially induces the synergistic actions of the symbiotic partners in enhancing plant drought tolerance.


Asunto(s)
Proteínas 14-3-3/metabolismo , Glomeromycota/metabolismo , Liasas Intramoleculares/metabolismo , Estrés Fisiológico/fisiología , Agua/metabolismo , Zea mays/metabolismo , Ácido Abscísico/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación Fúngica de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Micorrizas/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transducción de Señal , Zea mays/microbiología
14.
Antonie Van Leeuwenhoek ; 108(5): 1059-74, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26296378

RESUMEN

Rhizosphere and root-associated microbial communities are known to be related to soil-borne disease and plant health. In the present study, the microbial communities in rhizosphere soils and roots of both healthy and diseased Panax notoginseng were analyzed by high-throughput sequencing of 16S rRNA for bacteria and 18S rRNA internal transcribed spacer for fungi, to reveal the relationship of microbial community structure with plant health status. In total, 5593 bacterial operational taxonomic units (OTUs) and 963 fungal OTUs were identified in rhizosphere soils, while 1794 bacterial and 314 fungal OTUs were identified from root samples respectively. Principal coordinate analysis separated the microbial communities both in the rhizosphere soils and roots of diseased P. notoginseng from healthy plants. Compared to those of healthy P. notoginseng, microbial communities in rhizosphere soils and roots of diseased plants showed a decrease in alpha diversity. By contrast, bacterial community dissimilarity increased and fungal community dissimilarity decreased in rhizosphere soils of diseased plants, while both bacterial and fungal community dissimilarity in roots showed no significant difference between healthy and diseased plants. Redundancy analysis at the phylum level showed that mycorrhizal colonization and soil texture significantly affected microbial community composition in rhizosphere soils, whereas shoot nutrition status had a significant effect on microbial community composition in root samples. Our study provided strong evidence for the hypothesis that microbial diversity could potentially serve as an indicator for disease outbreak of medicinal plants, and supported the ecological significance of microbial communities in maintaining plant healthy and soil fertility.


Asunto(s)
Microbiota , Panax notoginseng/microbiología , Raíces de Plantas/microbiología , Rizosfera , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Biodiversidad , Ambiente , Hongos/clasificación , Hongos/genética , Suelo/química
15.
New Phytol ; 204(4): 968-78, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25103342

RESUMEN

We performed a landscape-scale investigation to compare the arbuscular mycorrhizal fungal (AMF) communities between grasslands and farmlands in the farming-pastoral ecotone of northern China. AMF richness and community composition were examined with 454 pyrosequencing. Structural equation modelling (SEM) and multivariate analyses were applied to disentangle the direct and indirect effects (mediated by multiple environmental factors) of land use on AMF. Land use conversion from grassland to farmland significantly reduced AMF richness and extraradical hyphal length density, and these land use types also differed significantly in AMF community composition. SEM showed that the effects of land use on AMF richness and hyphal length density in soil were primarily mediated by available phosphorus and soil structural quality. Soil texture was the strongest predictor of AMF community composition. Soil carbon, nitrogen and soil pH were also significantly correlated with AMF community composition, indicating that these abiotic variables could be responsible for some of the community composition differences among sites. Our study shows that land use has a partly predictable effect on AMF communities across this ecologically relevant area of China, and indicates that high soil phosphorus concentrations and poor soil structure are particularly detrimental to AMF in this fragile ecosystem.


Asunto(s)
Agricultura , Micorrizas/fisiología , Microbiología del Suelo , Biodiversidad , China , Ecosistema , Pradera , Datos de Secuencia Molecular , Micorrizas/genética , Suelo/química
16.
Biomolecules ; 14(9)2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39334881

RESUMEN

Porcine epidemic diarrhea virus (PEDV) has caused significant economic losses to the pig farming industry in various countries for a long time. Currently, there are no highly effective preventive or control measures available. Research into the pathogenic mechanism of PEDV has shown that it primarily causes infection by binding the S protein to the CD13 (APN) receptor on the membrane of porcine intestinal epithelial cells. The S1 region contains three neutralization epitopes and multiple receptor-binding domains, which are closely related to viral antigenicity and ad-sorption invasion. Nanobodies are a type of single-domain antibody that have been discovered in recent years. They can be expressed on a large scale through prokaryotic expression systems, which makes them cost-effective, stable, and less immunogenic. This study used a phage display library of nanobodies against the PEDV S1 protein. After three rounds of selection and enrichment, the DNA sequence of the highly specific nanobody S1Nb1 was successfully obtained. To obtain soluble nanobody S1Nb1, its DNA sequence was inserted into the vector Pcold and a solubility-enhancing SUMO tag was added. The resulting recombinant vector, Pcold-SUMO-S1Nb1, was then transformed into E. coli BL21(DE3) to determine the optimal expression conditions for the nanobody. Following purification using Ni-column affinity chromatography, Western blot analysis confirmed the successful purification of S1Nb1 carrying the solubility-enhancing tag. ELISA results demonstrated a strong affinity between the S1Nb1 nanobody and PEDV S1 protein.


Asunto(s)
Escherichia coli , Virus de la Diarrea Epidémica Porcina , Anticuerpos de Dominio Único , Virus de la Diarrea Epidémica Porcina/inmunología , Virus de la Diarrea Epidémica Porcina/genética , Anticuerpos de Dominio Único/inmunología , Anticuerpos de Dominio Único/genética , Anticuerpos de Dominio Único/aislamiento & purificación , Anticuerpos de Dominio Único/química , Escherichia coli/genética , Escherichia coli/metabolismo , Animales , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Porcinos , Biblioteca de Péptidos , Expresión Génica
17.
Biosens Bioelectron ; 259: 116402, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38788342

RESUMEN

In this work, a high-performance conjugated microporous polymer (CMP) decorated with BiOBr (Tr(PhXOD)3-CMP/BiOBr) is synthesized to application in construction of ultrasensitive photoelectrochemical (PEC) biosensor for sensing miRNA-122, by firstly coupling with efficient clip toehold-mediated allosteric bicycle strand displacement (ABSD). Notably, the Tr(PhXOD)3-CMP/BiOBr not only owns self-enhanced D-A-D structure that extremely shortens migration distance of photo-generated electron, but also forms Z-type heterostructure for accelerating electron-hole separation, thereby significantly enhancing the photocurrent with 10-fold higher than commonly used methods. Meanwhile, the clip toehold-mediated ABSD based on ternary linkage structure transformation avoids the attrition of invading strand, endowing the conservation of high concentration for undergoing rapid reaction with high-efficiency DNA amplification, which dramatically improves reaction time and superior target conversion. The experimental results indicate that proposed PEC biosensor had a high sensitivity to miRNA-122 with a detection limit of 0.49 fM, which provides a newly organic/inorganic photosensitive nanomaterials and efficient DNA strand displacement in bioanalytical and early clinical disease diagnosis.


Asunto(s)
Técnicas Biosensibles , Límite de Detección , MicroARNs , Polímeros , Técnicas Biosensibles/métodos , Polímeros/química , MicroARNs/análisis , Técnicas Electroquímicas/métodos , Humanos , ADN/química
18.
BMB Rep ; 57(8): 375-380, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38919016

RESUMEN

Early proatherogenic inflammation constitutes a significant risk factor for atherogenesis development. Despite this, the precise molecular mechanisms driving this pathological progression largely remain elusive. Our study unveils a pivotal role for the microRNA miR-328-5p in dampening endothelial inflammation by modulating the stability of JUNB (JunB proto-oncogene). Perturbation of miR-328-5p levels results in heightened monocyte adhesion to endothelial cells and enhanced transendothelial migration, while its overexpression mitigates these inflammatory processes. Furthermore, miR-328-5p hinders macrophage polarization toward the pro-inflammatory M1 phenotype, and exerts a negative influence on atherosclerotic plaque formation in vivo. By pinpointing JUNB as a direct miR-328-5p target, our research underscores the potential of miR-328-5p as a therapeutic target for inflammatory atherosclerosis. Reintroduction of JUNB effectively counteracts the anti-atherosclerotic effects of miR-328-5p, highlighting the promise of pharmacological miR-328-5p targeting in managing inflammatory atherosclerosis. [BMB Reports 2024; 57(8): 375-380].


Asunto(s)
Aterosclerosis , Inflamación , MicroARNs , Proto-Oncogenes Mas , MicroARNs/metabolismo , MicroARNs/genética , Aterosclerosis/metabolismo , Aterosclerosis/genética , Aterosclerosis/patología , Humanos , Inflamación/metabolismo , Inflamación/patología , Inflamación/genética , Animales , Células Endoteliales/metabolismo , Células Endoteliales/patología , Ratones , Macrófagos/metabolismo , Monocitos/metabolismo , Adhesión Celular/genética , Movimiento Celular/genética , Placa Aterosclerótica/patología , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/genética , Células Endoteliales de la Vena Umbilical Humana/metabolismo
19.
New Phytol ; 197(2): 617-630, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23157494

RESUMEN

Arbuscular mycorrhizal (AM) symbiosis is known to stimulate plant drought tolerance. However, the molecular basis for the direct involvement of AM fungi (AMF) in plant water relations has not been established. Two full-length aquaporin genes, namely GintAQPF1 and GintAQPF2, were cloned by rapid amplification of cDNA 5'- and 3'-ends from an AMF, Glomus intraradices. Aquaporin localization, activities and water permeability were examined by heterologous expression in yeast. Gene expression during symbiosis was also analyzed by quantitative real-time polymerase chain reaction. GintAQPF1 was localized to the plasma membrane of yeast, whereas GintAQPF2 was localized to both plasma and intracellular membranes. Transformed yeast cells exhibited a significant decrease in cell volume on hyperosmotic shock and faster protoplast bursting on hypo-osmotic shock. Polyethylene glycol (PEG) stimulated, but glycerol inhibited, the aquaporin activities. Furthermore, the expression of the two genes in arbuscule-enriched cortical cells and extraradical mycelia of maize roots was also enhanced significantly under drought stress. GintAQPF1 and GintAQPF2 are the first two functional aquaporin genes from AMF reported to date. Our data strongly support potential water transport via AMF to host plants, which leads to a better understanding of the important role of AMF in plant drought tolerance.


Asunto(s)
Acuaporinas/genética , Genes Fúngicos/genética , Glomeromycota/genética , Micorrizas/genética , Calcio/metabolismo , Clonación Molecular , Recuento de Colonia Microbiana , Biología Computacional , Sequías , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación de la Expresión Génica de las Plantas , Glomeromycota/crecimiento & desarrollo , Datos de Secuencia Molecular , Micelio/genética , Micorrizas/crecimiento & desarrollo , Presión Osmótica , Filogenia , Pichia/crecimiento & desarrollo , Pichia/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/microbiología , Transporte de Proteínas/genética , Protones , Protoplastos/metabolismo , Estrés Fisiológico/genética , Transformación Genética , Agua/metabolismo , Zea mays/genética , Zea mays/microbiología
20.
Mycorrhiza ; 23(4): 253-65, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23417725

RESUMEN

Medicinal plants have been used world-wide for thousands of years and are widely recognized as having high healing but minor toxic side effects. The scarcity and increasing demand for medicinal plants and their products have promoted the development of artificial cultivation of medicinal plants. Currently, one of the prominent issues in medicinal cultivation systems is the unstable quality of the products. Arbuscular mycorrhiza (AM) affects secondary metabolism and the production of active ingredients of medicinal plants and thus influence the quality of herbal medicines. In this review, we have assembled, analyzed, and summarized the effects of AM symbioses on secondary metabolites of medicinal plants. We conclude that symbiosis of AM is conducive to favorable characteristics of medicinal plants, by improving the production and accumulation of important active ingredients of medicinal plants such as terpenes, phenols, and alkaloids, optimizing the composition of different active ingredients in medicinal plants and ultimately improving the quality of herbal materials. We are convinced that the AM symbiosis will benefit the cultivation of medicinal plants and improve the total yield and quality of herbal materials. Through this review, we hope to draw attention to the status and prospects of, and arouse more interest in, the research field of medicinal plants and mycorrhiza.


Asunto(s)
Hongos/fisiología , Micorrizas/fisiología , Extractos Vegetales/metabolismo , Plantas Medicinales/metabolismo , Plantas Medicinales/microbiología , Simbiosis , Extractos Vegetales/análisis , Plantas Medicinales/química
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