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1.
Sci Total Environ ; : 175335, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39117195

RESUMEN

The excessive application of phosphorus (P) fertiliser and its poor utilisation efficiency have led to significant amounts of P being retained in agricultural soils in unavailable forms. The application of alkaline lignin to soil and its inoculation with arbuscular mycorrhizal fungi (AMF) have both been shown to improve plant P nutrition. However, their combined effects on soil P transformation remain unclear, particularly in cadmium (Cd)-contaminated soils. A potting experiment was conducted to examine the combined effects of AMF and alkaline lignin on soil P and Cd bioavailability and on the uptake of P and Cd by lettuce (Lactuca sativa L.) that were grown for 56 d in a growth chamber. Combined AMF and alkaline lignin treatment increased soil P availability and alkaline phosphatase activity. It furthermore increased bioavailable Cd concentrations of rhizosphere and bulk soils by 48 % and 72 %, respectively, and the Cd concentration in roots by 85 %, but the Cd concentration was not affected in the edible parts (shoots) of the lettuce. Moreover, the combined treatment increased shoot biomass by 26-70 % and root biomass by 99-164 %. Our findings suggested that the combined use of AMF and alkaline lignin mobilised both P and Cd in soil but did not increase the accumulation of Cd in the shoots of plants growing in Cd-contaminated soils, these results would provide guideline for increasing Cd tolerance of plants and their yield.

2.
Methods Mol Biol ; 2838: 221-237, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39126636

RESUMEN

Epizootic hemorrhagic disease virus (EHDV) is transmitted by Culicoides biting midges. Studies aiming to predict the likely spread of EHDV require an understanding of the viral infection and replication kinetics within these insects, including the proportion of the insect population that are able to support virus transmission. Here, we describe methods for the infection of Culicoides with EHDV in the laboratory via oral infection using an artificial membrane system or a cotton pledget and intrathoracic (IT) inoculation. Each method can be used to explore determinants of vector competence of Culicoides species and populations for EHDV.


Asunto(s)
Ceratopogonidae , Virus de la Enfermedad Hemorrágica Epizoótica , Insectos Vectores , Infecciones por Reoviridae , Animales , Ceratopogonidae/virología , Virus de la Enfermedad Hemorrágica Epizoótica/fisiología , Insectos Vectores/virología , Infecciones por Reoviridae/transmisión , Infecciones por Reoviridae/virología , Infecciones por Reoviridae/veterinaria
3.
Microb Cell Fact ; 23(1): 226, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39127680

RESUMEN

BACKGROUND: Endophytic fungi (EF) reside within plants without causing harm and provide benefits such as enhancing nutrients and producing bioactive compounds, which improve the medicinal properties of host plants. Selecting plants with established medicinal properties for studying EF is important, as it allows a deeper understanding of their influence. Therefore, the study aimed to investigate the impact of EF after inoculating the medicinal plant Perilla frutescens, specifically focusing on their role in enhancing medicinal properties. RESULTS: In the current study, the impact of two EF i.e., Irpex lenis and Schizophyllum commune isolated from A. bracteosa was observed on plant Perilla frutescens leaves after inoculation. Plants were divided into four groups i.e., group A: the control group, group B: inoculated with I. lenis; group C: inoculated with S. commune and group D: inoculated with both the EF. Inoculation impact of I. lenis showed an increase in the concentration of chlorophyll a (5.32 mg/g), chlorophyll b (4.46 mg/g), total chlorophyll content (9.78 mg/g), protein (68.517 ± 0.77 mg/g), carbohydrates (137.886 ± 13.71 mg/g), and crude fiber (3.333 ± 0.37%). Furthermore, the plants inoculated with I. lenis showed the highest concentrations of P (14605 mg/kg), Mg (4964.320 mg/kg), Ca (27389.400 mg/kg), and Mn (86.883 mg/kg). The results of the phytochemical analysis also indicated an increased content of total flavonoids (2.347 mg/g), phenols (3.086 mg/g), tannins (3.902 mg/g), and alkaloids (1.037 mg/g) in the leaf extract of P. frutescens inoculated with I. lenis. Thus, overall the best results of inoculation were observed in Group B i.e. inoculated with I. lenis. GC-MS analysis of methanol leaf extract showed ten bioactive constituents, including 9-Octadecenoic acid (Z)-, methyl ester, and hexadecanoic acid, methyl ester as major constituents found in all the groups of P. frutescens leaves. The phenol (gallic acid) and flavonoids (rutin, kaempferol, and quercetin) were also observed to increase after inoculation by HPTLC analysis. The enhancement in the phytochemical content was co-related with improved anti-oxidant potential which was analyzed by DPPH (% Inhibition: 83.45 µg/ml) and FRAP (2.980 µM Fe (II) equivalent) assay as compared with the control group. CONCLUSION: Inoculation with I. lenis significantly enhances the uptake of nutritional constituents, phytochemicals, and antioxidant properties in P. frutescens, suggesting its potential to boost the therapeutic properties of host plants.


Asunto(s)
Antioxidantes , Endófitos , Perilla frutescens , Fitoquímicos , Hojas de la Planta , Schizophyllum , Perilla frutescens/química , Perilla frutescens/metabolismo , Antioxidantes/metabolismo , Schizophyllum/metabolismo , Fitoquímicos/química , Fitoquímicos/metabolismo , Fitoquímicos/farmacología , Endófitos/metabolismo , Hojas de la Planta/microbiología , Hojas de la Planta/química , Clorofila/metabolismo
4.
Artículo en Inglés | MEDLINE | ID: mdl-39101514

RESUMEN

BACKGROUND: Gambling advertising employs a range of persuasive strategies. We therefore aimed to evaluate a counter-advertising intervention video to increase resilience to gambling advertising persuasion. METHODS: Three in-depth focus groups were conducted, and each group contained a mixture of gambling-related academics (N = 12) and experts with lived experience of gambling-related harm (N = 10). Participants were given access to the intervention video and provided feedback during the focus groups. Qualitative data were audio recorded and thematically analysed by the research team. RESULTS: Three main themes were identified. First, participants recommended a shorter video that had a simplified and digestible structure. Second, frequent real-world examples of gambling advertisements within the video were discouraged, and the inclusion of a relatable human voiceover was considered imperative to the receptiveness of the video. Finally, participants deemed it important to deliver psychologically grounded yet jargon-free content via a conversational style. An overall narrative framed by consumer-protection was also preferred in order to increase acceptance of the video content, rather than a more didactic framing. CONCLUSIONS: Evaluating the acceptability of a counter advertising intervention video provided valuable insight from both an academic and lived-experience perspective. Such insight is instrumental to the meaningful co-design of counter-advertising interventions.

5.
Plant Physiol Biochem ; 215: 108979, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39094483

RESUMEN

Inoculation of Azospirillum in maize has become a standard practice in Latin America. However, information on the behavior and population survival of the Azospirillum post-inoculation is scarce, making standardization difficult and generating variations in inoculation efficiency across assays. In this study, we tracked the colonization of three agriculturally relevant Azospirillum strains (Ab-V5, Az39, and the ammonium excreting HM053) after different inoculation methods in maize crops by qPCR. Besides, we assessed their ability to promote maize growth by measuring biometric parameters after conducting a greenhouse essay over 42 days. Inoculated plants exhibited Azospirillum population ranging from 103 to 107 cells plant-1 throughout the experiment. While all strains efficiently colonized roots, only A. argentinense Az39 demonstrated bidirectional translocation between roots and shoots, which characterizes a systemic behavior. Optimal inoculation methods for plant growth promotion varied among strains: soil inoculation promoted the best maize growth for the Ab-V5 and Az39 strains, while seed inoculation proved most effective for HM053. The findings of this study demonstrate that the inoculation method affects the behavior of Azospirillum strains and their effectiveness in promoting maize growth, thereby guiding practices to enhance crop yield.

6.
R Soc Open Sci ; 11(6): 231711, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39100154

RESUMEN

Inoculation theory research offers a promising psychological 'vaccination' against misinformation. But are people willing to take it? Expanding on the inoculation metaphor, we introduce the concept of 'inoculation hesitancy' as a framework for exploring reluctance to engage with misinformation interventions. Study 1 investigated whether individuals feel a need for misinformation inoculations. In a comparative self-evaluation, participants assessed their own experiences with misinformation and expectations of inoculation and compared them to those of the average person. Results exposed a better-than-average effect. While participants were concerned over the problem of misinformation, they estimated that they were less likely to be exposed to it and more skilful at detecting it than the average person. Their self-described likelihood of engaging with inoculation was moderate, and they believed other people would benefit more from being inoculated. In Study 2, participants evaluated their inclination to watch inoculation videos from sources varying in trustworthiness and political affiliation. Results suggest that participants are significantly less willing to accept inoculations from low-trust sources and less likely to accept inoculations from partisan sources that are antithetical to their own political beliefs. Overall, this research identifies motivational obstacles in reaching herd immunity with inoculation theory, guiding future development of inoculation interventions.

7.
Plants (Basel) ; 13(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39124248

RESUMEN

Seed treatment with plant growth-promoting bacteria represents the primary strategy to incorporate them into agricultural ecosystems, particularly for crops under extensive management, such as maize. In this study, we evaluated the seed bacterization levels, root colonization patterns, and root competitiveness of a collection of autochthonous Pseudomonas isolates that have demonstrated several plant-probiotic abilities in vitro. Our findings indicate that the seed bacterization level, both with and without the addition of various protectants, is specific to each Pseudomonas strain, including their response to seed pre-hydration. Bacterization kinetics revealed that while certain isolates persisted on seed surfaces for up to 4 days post-inoculation (dpi), others experienced a rapid decline in viability after 1 or 2 dpi. The observed differences in seed bacterization levels were consistent with the root colonization densities observed through confocal microscopy analysis, and with root competitiveness quantified via selective plate counts. Notably, isolates P. protegens RBAN4 and P. chlororaphis subsp. aurantiaca SMMP3 demonstrated effective competition with the natural microflora for colonizing the maize rhizosphere and both promoted shoot and root biomass production in maize assessed at the V3 grown stage. Conversely, P. donghuensis SVBP6 was detected at very low levels in the maize rhizosphere, but still exhibited a positive effect on plant parameters, suggesting a growth-stimulatory effect during the early stages of plant development. In conclusion, there is a considerable strain-specific variability in the maize seed bacterization and survival capacities of Pseudomonas isolates with plant-probiotic traits, with a correlation in their root competitiveness under natural conditions. This variability must be understood to optimize their adoption as inputs for the agricultural system. Our experimental approach emphasizes the critical importance of tailoring seed bacterization treatments for each inoculant candidate, including the selection and incorporation of protective substances. It should not be assumed that all bacterial cells exhibit a similar performance.

8.
Front Microbiol ; 15: 1426166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38989019

RESUMEN

Phosphorus (P) is a critical nutrient for plant growth, yet its uptake is often hindered by soil factors like clay minerals and metal oxides such as aluminum (Al), iron (Fe), and calcium (Ca), which bind P and limit its availability. Phosphate-solubilizing bacteria (PSB) have the unique ability to convert insoluble P into a soluble form, thereby fostering plant growth. This study aimed to assess the efficacy of inoculation of Bacillus megaterium B119 (rhizospheric) and B. subtilis B2084 (endophytic) via seed treatment in enhancing maize yield, grain P content, and enzyme activities across two distinct soil types in field conditions. Additionally, we investigated various mechanisms contributing to plant growth promotion, compatibility with commercial inoculants, and the maize root adhesion profile of these strains. During five crop seasons in two experimental areas in Brazil, Sete Lagoas-MG and Santo Antônio de Goiás-GO, single inoculations with either B119 or B2084 were implemented in three seasons, while a co-inoculation with both strains was applied in two seasons. All treatments received P fertilizer according to plot recommendations, except for control. Both the Bacillus strains exhibited plant growth-promoting properties relevant to P dynamics, including phosphate solubilization and mineralization, production of indole-3-acetic acid (IAA)-like molecules, siderophores, exopolysaccharides (EPS), biofilms, and phosphatases, with no antagonism observed with Azospirillum and Bradyrizhobium. Strain B2084 displayed superior maize root adhesion compared to B119. In field trials, single inoculations with either B119 or B2084 resulted in increased maize grain yield, with relative average productivities of 22 and 16% in Sete Lagoas and 6 and 3% in Santo Antônio de Goiás, respectively. Co-inoculation proved more effective, with an average yield increase of 24% in Sete Lagoas and 11% in Santo Antônio de Goiás compared to the non-inoculated control. Across all seasons, accumulated grain P content correlated with yield, and soil P availability in the rhizosphere increased after co-inoculation in Santo Antônio de Goiás. These findings complement previous research efforts and have led to the validation and registration of the first Brazilian inoculant formulated with Bacillus strains for maize, effectively enhancing and P grain content.

9.
BMC Plant Biol ; 24(1): 706, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054409

RESUMEN

BACKGROUND: Opuntia ficus-indica (L.) Miller is dominantly growing on degraded soils in arid and semi-arid areas. The plants might establish a strong association with arbuscular mycorrhizal fungi (AMF) to adapt to nutrient, drought, and herbivore insect stress. The objective of this study was to investigate the effects of AMF inoculations and variable soil water levels (SWA) on the biomass, nutrient concentration, nutritional composition, and nutrient digestibility of the spiny and spineless O. ficus-indica by inducing resistance to cochineal stress. One mother Opuntia ficus-indica cladode was planted in a single pot in each field with 24 kg mixed soil. AMF inoculums were cultured in sorghum plants in a greenhouse and were inoculated in the planted cladodes. The planted cladodes were arranged using a completely randomized design (CRD) with three factors: AMF (present and absent); O. ficus-indica type (spiny and spineless) and four water treatments with 0-25% of plant available soil water (SWA), 25-50% of SWA, 50-75% of SWA, and 75-100% of SWA. RESULTS: Drought stress reduced the below and above-ground biomass, cladode nutrient content, nutritional composition, and in vitro dry matter digestibility (IVDMD) and in vitro organic matter digestibility (IVOMD). AMF colonization significantly increased biomass production with significant changes in the macro and micro-nutrient concentrations of O. ficus-indica. AMF inoculation significantly increased the IVDMD and IVOMD of both O. ficus-indica types by improving the biomass, organic matter (OM), crude protein (CP), and reduced fiber and ash contents. AMF-inoculated cladodes improved the nutrient concentrations of the cladodes. AMF caused an increase in biomass production, increased tolerance to cochineal stress, and improved nutrient concentration, nutritional composition, and nutrient digestibility performance of O. ficus-indica plants. CONCLUSIONS: AMF improved the performance of the O. ficus-indica plant to resist drought and cochineal stress and increased the biomass, nutrient concentration, nutritional composition, and nutrient digestibility. The potential of O. ficus-indica to adapt to cochineal stress is controlled by the macro and micro-nutrient concentration brought by the AMF association.


Asunto(s)
Biomasa , Micorrizas , Valor Nutritivo , Opuntia , Micorrizas/fisiología , Opuntia/microbiología , Animales , Suelo/química , Sequías , Agua/metabolismo
10.
J Microbiol Methods ; 224: 107003, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39038560

RESUMEN

The reduction of antimicrobial susceptibility testing (AST) time-to-result is a central need, especially in sepsis treatment. The current automated rapid ASTs are still too expensive for many laboratories. We aimed to evaluate three pre-treatment methods for a same-day inoculation on both automated AST platforms available in our laboratory. We tested 100 Enterobacterales or staphylococci positive bottles. We obtained good results with the different methods and instruments. In particular, Vitek-2 showed good performances with Enterobacterales AST when inoculated with bacterial pellet (96.6% categorical agreement - CA-, 93.3% essential agreement - EA). Also short-term incubation colonies for staphylococci AST had acceptable CA (94.2%), even if with 77.5% EA. MicroScan system for staphylococci AST with both short-term incubation and direct blood inoculation reached >95% CA, but 92.5% and 83.6% EA, respectively. On the other hand, Enterobacterales AST showed optimal performances only with bacterial pellet inoculation (97.6% CA). In fact, direct blood inoculation showed not acceptable parameters for several molecules. Both systems allow a 24-h reduction in time-to-result, by using the same instruments of routine activity after rapid and cheap pre-treatments.

11.
Environ Sci Pollut Res Int ; 31(33): 46002-46022, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38980484

RESUMEN

Mining-related lead (Pb) pollution of the soil poses serious hazards to ecosystems and living organisms, including humans. Improved heavy metal phytoremediation efficacy, achieved by using phytostabilizing plants assisted by plant-growth-promoting (PGP) microorganisms, has been presented as an effective strategy for remediating polluted soils. The objective of this research was to examine the response and potential of the plant-growth-promoting bacterium LMR356, a Rhodococcus qingshengii strain isolated from an abandoned mining soil, under lead stress conditions. Compared to non-contaminated culture media, the presence of lead induced a significant decrease in auxin production (from 21.17 to 2.65 µg mL-1) and phosphate solubilization (from 33.60 to 8.22 mg L-1), whereas other PGP traits increased drastically, such as 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity (from 38.17 to 71.37 nmol mg-1 h-1 α-ketobutyrate), siderophore production (from 69 to 83%), exopolysaccharide production (from 1952.28 to 3637.72 mg mL-1), biofilm formation, and motility. We, therefore, investigated the behavior of Sulla spinosissima L. in the presence or absence of this strain under a variety of experimental conditions. Under hydroponic conditions, Sulla plants showed endurance to varying lead concentrations (500-1000 µM). Inoculation of plants with Rhodococcus qingshengii strain LMR356 enhanced plant tolerance, as demonstrated by the increase in plant biomass (ranging from 14.41 to 79.12%) compared to non-inoculated Pb-stressed and non-stressed control plants. Antioxidant enzyme activities (increasing by -42.71 to 126.8%) and chlorophyll (383.33%) and carotenoid (613.04%) content were also augmented. In addition to its impact on plant lead tolerance, strain LMR356 showed a growth-promoting effect on Sulla plants when cultivated in sterilized non-contaminated sand. Parameters such as plant biomass (16.57%), chlorophyll (24.14%), and carotenoid (30%) contents, as well as ascorbate peroxidase (APX), peroxidase (POD), and catalase (CAT) activities, were all elevated compared to non-inoculated plants. Furthermore, when the same plant species was cultivated in highly polluted soil, inoculation increased plant biomass and improved its physiological properties. These findings demonstrate that LMR356 is a phytobeneficial bacterial strain capable of enhancing Sulla growth under normal conditions and improving its heavy metal tolerance in multi-polluted soils. Thus, it can be considered a promising biofertilizer candidate for growing Sulla spinosissima L. or other selected plants intended for application in restoration and stabilization initiatives aimed at reviving and safeguarding environmentally compromised and polluted soils after mining activities.


Asunto(s)
Biodegradación Ambiental , Plomo , Rhodococcus , Contaminantes del Suelo , Rhodococcus/metabolismo , Microbiología del Suelo , Desarrollo de la Planta/efectos de los fármacos
12.
Plant Cell Environ ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39016637

RESUMEN

Wheat yellow mosaic virus (WYMV) causes severe viral wheat disease in Asia. The WYMV P1 protein encoded by RNA2 has viral suppressor of RNA silencing (VSR) activity to facilitate virus infection, however, VSR activity has not been identified for P2 protein encoded by RNA2. In this study, P2 protein exhibited strong VSR activity in Nicotiana benthamiana at the four-leaf stage, and point mutants P70A and G230A lost VSR activity. Protein P2 interacted with calmodulin (CaM) protein, a gene-silencing associated protein, while point mutants P70A and G230A did not interact with it. Competitive bimolecular fluorescence complementation and competitive co-immunoprecipitation experiments showed that P2 interfered with the interaction between CaM and calmodulin-binding transcription activator 3 (CAMTA3), but the point mutants P70A and G230A could not. Mechanical inoculation of wheat with in vitro transcripts of WYMV infectious cDNA clone further confirmed that VSR-deficient mutants P70A and G230A decreased WYMV infection in wheat plants compared with the wild type. In addition, RNA silencing, temperature, ubiquitination and autophagy had significant effects on accumulation of P2 protein in N. benthamiana leaves. In conclusion, WYMV P2 plays a VSR role in N. benthamiana and promotes virus infection by interfering with calmodulin-related antiviral RNAi defense.

13.
J Math Biol ; 89(2): 25, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963509

RESUMEN

The Ebola virus disease (EVD) has been endemic since 1976, and the case fatality rate is extremely high. EVD is spread by infected animals, symptomatic individuals, dead bodies, and contaminated environment. In this paper, we formulate an EVD model with four transmission modes and a time delay describing the incubation period. Through dynamical analysis, we verify the importance of blocking the infection source of infected animals. We get the basic reproduction number without considering the infection source of infected animals. And, it is proven that the model has a globally attractive disease-free equilibrium when the basic reproduction number is less than unity; the disease eventually becomes endemic when the basic reproduction number is greater than unity. Taking the EVD epidemic in Sierra Leone in 2014-2016 as an example, we complete the data fitting by combining the effect of the media to obtain the unknown parameters, the basic reproduction number and its time-varying reproduction number. It is shown by parameter sensitivity analysis that the contact rate and the removal rate of infected group have the greatest influence on the prevalence of the disease. And, the disease-controlling thresholds of these two parameters are obtained. In addition, according to the existing vaccination strategy, only the inoculation ratio in high-risk areas is greater than 0.4, the effective reproduction number can be less than unity. And, the earlier the vaccination time, the greater the inoculation ratio, and the faster the disease can be controlled.


Asunto(s)
Número Básico de Reproducción , Ebolavirus , Fiebre Hemorrágica Ebola , Conceptos Matemáticos , Modelos Biológicos , Fiebre Hemorrágica Ebola/transmisión , Fiebre Hemorrágica Ebola/prevención & control , Fiebre Hemorrágica Ebola/epidemiología , Número Básico de Reproducción/estadística & datos numéricos , Humanos , Animales , Sierra Leona/epidemiología , Ebolavirus/patogenicidad , Ebolavirus/fisiología , Epidemias/estadística & datos numéricos , Epidemias/prevención & control , Simulación por Computador , Modelos Epidemiológicos , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos
14.
Bioresour Technol ; 407: 131114, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39009049

RESUMEN

This research examined the impact of exogenous thermophilic bacteria and ripening agents on greenhouse gas (GHG) emission, enzyme activity, and microbial community during composting. The use of ripening agents alone resulted in a 30.9 % reduction in CO2 emissions, while the use of ripening agents and thermophilic bacteria resulted in a 50.8 % reduction in N2O emissions. Pearson's analysis showed that organic matter and nitrate nitrogen were the key parameters affecting GHG emissions. There was an inverse correlation between CO2 and CH4 releases and methane monooxygenase α subunit and N2O reductase activity (P<0.05). Additionally, N2O emissions were positively related to ß-1, 4-N-acetylglucosaminidase, and ammonia monooxygenase activity (P<0.05). Deinococcota, Chloroflexi, and Bacteroidota are closely related to CO2 and N2O emissions. Overall, adding thermophilic bacteria represents an effective strategy to mitigate GHG emissions during composting.


Asunto(s)
Bacterias , Compostaje , Gases de Efecto Invernadero , Bacterias/metabolismo , Compostaje/métodos , Dióxido de Carbono , Metano/metabolismo , Óxido Nitroso/metabolismo , Microbiología del Suelo , Microbiota/fisiología , Suelo/química
15.
Sci Rep ; 14(1): 16914, 2024 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-39043743

RESUMEN

Manipulation of the rumen microbial ecosystem in early life may affect ruminal fermentation and enhance the productive performance of dairy cows. The objective of this experiment was to evaluate the effects of dosing three different types of microbial inoculum on the rumen epithelium tissue (RE) transcriptome and the rumen epimural metatranscriptome (REM) in dairy calves. For this objective, 15 Holstein bull calves were enrolled in the study at birth and assigned to three different intraruminal inoculum treatments dosed orally once weekly from three to six weeks of age. The inoculum treatments were prepared from rumen contents collected from rumen fistulated lactating cows and were either autoclaved (control; ARF), processed by differential centrifugation to create the bacterial-enriched inoculum (BE), or through gravimetric separation to create the protozoal-enriched inoculum (PE). Calves were fed 2.5 L/d pasteurized waste milk 3x/d from 0 to 7 weeks of age and texturized starter until euthanasia at 9 weeks of age, when the RE tissues were collected for transcriptome and microbial metatranscriptome analyses, from four randomly selected calves from each treatment. The different types of inoculum altered the RE transcriptome and REM. Compared to ARF, 9 genes were upregulated in the RE of BE and 92 in PE, whereas between BE and PE there were 13 genes upregulated in BE and 114 in PE. Gene ontology analysis identified enriched GO terms in biological process category between PE and ARF, with no enrichment between BE and ARF. The RE functional signature showed different KEGG pathways related to BE and ARF, and no specific KEGG pathway for PE. We observed a lower alpha diversity index for RE microbiome in ARF (observed genera and Chao1 (p < 0.05)). Five microbial genera showed a significant correlation with the changes in host gene expression: Roseburia (25 genes), Entamoeba (two genes); Anaerosinus, Lachnospira, and Succiniclasticum were each related to one gene. sPLS-DA analysis showed that RE microbial communities differ among the treatments, although the taxonomic and functional microbial profiles show different distributions. Co-expression Differential Network Analysis indicated that both BE and PE had an impact on the abundance of KEGG modules related to acyl-CoA synthesis, type VI secretion, and methanogenesis, while PE had a significant impact on KEGGs related to ectoine biosynthesis and D-xylose transport. Our study indicated that artificial dosing with different microbial inocula in early life alters not only the RE transcriptome, but also affects the REM and its functions.


Asunto(s)
Rumen , Transcriptoma , Animales , Bovinos , Rumen/microbiología , Rumen/metabolismo , Epitelio/metabolismo , Epitelio/microbiología , Masculino , Microbioma Gastrointestinal/genética , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Perfilación de la Expresión Génica/métodos
16.
Huan Jing Ke Xue ; 45(7): 4082-4089, 2024 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-39022956

RESUMEN

The rapid cultivation of partial nitritation/ANAMMOX (PN/A) granular sludge in a continuous-flow mode is one of the key technologies for efficient biological nitrogen removal in domestic wastewater treatment. Compared with that in PN/A granular sludge, PN granular sludge demonstrates a shorter incubation period and suitability for batch culture. It is also a good carrier for enriching ANAMMOX (AMX) bacteria. In this study, we established a continuous-flow autotrophic nitrogen removal process in three continuously stirred tank reactors (CSTR) (R1-R3) by hybrid-inoculating PN/A and PN granular sludge at the mass ratios of 3∶1, 1∶1, and 1∶3, respectively. By implementing high ammonium nitrogen loading and short hydraulic retention time, continuous autotrophic nitrogen removal processes were successfully started up in the three CSTRs. The results showed that compared with that of R1 and R2, R3 had a longer start-up time but a similar steady-state nitrogen removal performance. The total nitrogen removal load of R3 could be more than 2.6 kg·ï¼ˆm3·d)-1. Intriguingly, the inoculated PN granular sludge served as a precursor for PN/A granular sludge cultivation. This approach facilitated the enrichment of anaerobic ammonia-oxidizing bacteria (AMX) by introducing abundant ammonium-oxidizing bacteria (AOB) and nitrite nitrogen substrates into the CSTR. According to the results of high-throughput sequencing, the microbial abundance and diversity of the mature granules in R1-R3 were significantly higher than those of the inoculation sludge. AOB (genus Nitrosomonas), AMX (genera Candidatus Kuenenia and Candidatus Brocadia), and symbiotic heterotrophs, such as Chloroflexi, Bacteroidetes, and Chlorobi, drove the autotrophic nitrogen removal process and maintained the stability of the granular structure. In summary, a novel start-up strategy of hybrid-inoculating granular sludge was provided for a continuous-flow autotrophic nitrogen removal in engineering application.


Asunto(s)
Procesos Autotróficos , Reactores Biológicos , Nitrógeno , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Reactores Biológicos/microbiología , Nitrógeno/metabolismo , Nitrógeno/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Aguas del Alcantarillado/microbiología , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Bacterias/genética , Aguas Residuales/química , Compuestos de Amonio/metabolismo , Compuestos de Amonio/aislamiento & purificación
17.
Parasit Vectors ; 17(1): 303, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-38997729

RESUMEN

BACKGROUND: Malaria transmission is known to be perennial and heterogeneous in Benin. Studies assessing local malaria prevalence, transmission levels and vector characteristics are critical for designing, monitoring and evaluating new vector control interventions in community trials. We conducted a study in the Zakpota sub-district of central Benin to collect baseline data on household characteristics, malaria prevalence, vector characteristics and transmission dynamics in preparation for a randomised controlled trial to evaluate the community impact of VECTRON™ T500, a new broflanilide indoor residual spraying (IRS) product. METHODS: A total of 480 children under 5 years of age from the 15 villages of the sub-district were tested for malaria by rapid diagnostic tests (RDTs). Mosquitoes were collected by human landing catches (HLCs), pyrethrum spray catches (PSCs) and Centers for Disease Control and Prevention miniature light traps (CDC-LTs) in selected houses in each village to assess vector density, composition, vector infectivity and prevalence of insecticide resistance markers. Bioassays were performed to detect vector susceptibility to pyrethroids, broflanilide (6 µg/bottle) and clothianidin (90 µg/bottle). RESULTS: A total of 9080 households were enumerated in the 15 study villages. Insecticide-treated net (ITN) usage was > 90%, with 1-2 ITNs owned per household. Houses were constructed mainly with cement (44%) and mud (38%) substrates or a mixture of cement and mud (18%), and 60% of them had open eaves. The overall prevalence of P. falciparum infection was 19% among surveyed children: 20% among females and 18% among males. The haemoglobin rate showed an anaemia (< 11 g/dl) prevalence of 66%. Anopheles coluzzii and An. gambiae sensu stricto (s.s.) were the two vector species present at an overall proportion of 46% versus 54%, respectively. The human biting rate was 2.3 bites per person per night (b/p/n) and biting occurred mostly indoors compared with outdoors (IRR = 0.776; P = 0.001). The overall proportion of outdoor biting was 44% and exceeded indoor biting in three villages. The sporozoite rate was 2% with a combined yearly entomological inoculation rate (EIR) of 16.1 infected bites per person per year (ib/p/y). There was great variability in malaria transmission risk across the villages, with EIR ranging from 0 to 29.3 ib/p/y. The vector population showed a high intensity of resistance to pyrethroids across the study villages but was largely susceptible to broflanilide and clothianidin. CONCLUSIONS: This study found high levels of malaria prevalence, vector density and transmission in the Zakpota sub-district despite the wide use of insecticide-treated nets. The vector population was mostly indoor resting and showed a high intensity of pyrethroid resistance but was generally fully susceptible to broflanilide. These findings demonstrated the suitability of the study area for the assessment of VECTRON™ T500 in a community randomised trial.


Asunto(s)
Anopheles , Insecticidas , Malaria , Control de Mosquitos , Mosquitos Vectores , Benin/epidemiología , Humanos , Animales , Insecticidas/farmacología , Control de Mosquitos/métodos , Prevalencia , Preescolar , Mosquitos Vectores/efectos de los fármacos , Mosquitos Vectores/parasitología , Anopheles/efectos de los fármacos , Anopheles/parasitología , Anopheles/fisiología , Femenino , Malaria/transmisión , Malaria/prevención & control , Malaria/epidemiología , Masculino , Lactante , Resistencia a los Insecticidas , Piretrinas/farmacología
18.
Sci Total Environ ; 946: 174461, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38964380

RESUMEN

Inoculation is widely used in composting to improve the mineralization process, however, the link of fungal inoculant to humification is rarely proposed. The objective of this study was to investigate the effect of compound fungal inoculation on humification process and fungal community dynamics in corn straw composting with two different kinds of nitrogen sources [pig manure (PM) and urea (UR)]. Structural equation modeling and random forest analysis were conducted to identify key fungi and explore the fungi-mediated humification mechanism. Results showed that fungal inoculation increased the content of humic acids in PM and UR by 71.76 % and 53.01 % compared to control, respectively. High-throughput sequencing indicated that there were more key fungal genera for lignin degradation in PM especially in the later stage of composting, but a more complex fungal (genera) connections with lower humification degree was found in UR. Network analysis and random forest suggested that inoculation promoted dominant genus such as Coprinus, affecting lignocellulose degradation. Structural equation modeling indicated that fungal inoculation could promote humification by direct pathway based on lignin degradation and indirect pathway based on stimulating the indigenous microbes such as Scedosporiu and Coprinus for the accumulation of carboxyl and polyphenol hydroxyl groups. In summary, fungal inoculation is suitable to be used combining with complex nitrogen source such as pig manure in straw composting.


Asunto(s)
Compostaje , Hongos , Sustancias Húmicas , Estiércol , Nitrógeno , Zea mays , Sustancias Húmicas/análisis , Nitrógeno/análisis , Estiércol/microbiología , Microbiología del Suelo , Animales , Porcinos , Lignina/metabolismo
19.
Vet Res ; 55(1): 94, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075607

RESUMEN

Chronic wasting disease (CWD), a prion disease affecting cervids, has been known in North America (NA) since the 1960s and emerged in Norway in 2016. Surveillance and studies have revealed that there are different forms of CWD in Fennoscandia: contagious CWD in Norwegian reindeer and sporadic CWD in moose and red deer. Experimental studies have demonstrated that NA CWD prions can infect various species, but thus far, there have been no reports of natural transmission to non-cervid species. In vitro and laboratory animal studies of the Norwegian CWD strains suggest that these strains are different from the NA strains. In this work, we describe the intracerebral transmission of reindeer CWD to six scrapie-susceptible sheep. Detection methods included immunohistochemistry (IHC), western blot (WB), enzyme-linked immunosorbent assay (ELISA), real-time quaking-induced conversion (RT-QuIC) and protein misfolding cyclic amplification (PMCA). In the brain, grey matter vacuolation was limited, while all sheep exhibited vacuolation of the white matter. IHC and WB conventional detection techniques failed to detect prions; however, positive seeding activity with the RT-QuIC and PMCA amplification techniques was observed in the central nervous system of all but one sheep. Prions were robustly amplified in the lymph nodes of all animals, mainly by RT-QuIC. Additionally, two lymph nodes were positive by WB, and one was positive by ELISA. These findings suggest that sheep can propagate reindeer CWD prions after intracerebral inoculation, resulting in an unusual disease phenotype and prion distribution with a low amount of detectable prions.


Asunto(s)
Priones , Reno , Enfermedad Debilitante Crónica , Animales , Enfermedad Debilitante Crónica/transmisión , Ovinos , Priones/metabolismo , Noruega , Encéfalo/metabolismo , Fenotipo , Enfermedades de las Ovejas/transmisión
20.
Microorganisms ; 12(7)2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39065246

RESUMEN

Co-inoculation of soybeans with Bradyrhizobium and plant growth-promoting bacteria has displayed promise for enhancing plant growth, but concrete evidence of its impact on soybean yields is limited. Therefore, this study assessed the comparative efficacy of two 1-aminocyclopropane-1-carboxylate deaminase-producing Pseudomonas species (OFT2 and OFT5) co-inoculated with Bradyrhizobium ottawaense (SG09) on the growth, physiology, nodulation efficiency, and grain yield of three major Japanese soybean cultivars: Enrei, Fukuyutaka, and Satonohohoemi. The experiments were conducted in a warehouse under natural light conditions. The treatments included the inoculation of SG09, SG09 + OFT2, and SG09 + OFT5. Compared with Bradyrhizobium inoculation alone, co-inoculation led to significant improvements in nodulation efficiency, growth, and physiological performance in the Enrei and Fukuyutaka cultivars, but not in the Satonohohoemi cultivar. Furthermore, co-inoculation significantly boosted the total nitrogen content and ion uptake in the shoots, ultimately leading to a remarkable improvement in the grain yield in the Enrei and Fukuyutaka cultivars. These findings contribute to clarifying the interplay among Bradyrhizobium, Pseudomonas, and the plant host cultivar. Notably, Bradyrhizobium-Pseudomonas co-inoculation represents a potentially effective biofertilization strategy for soybean production, highlighting promising avenues for sustainable agricultural practices.

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