Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 9 de 9
Filtre
1.
Braz. j. biol ; 83: 1-13, 2023. tab, graf
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1468809

Résumé

Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.


Sujets)
Animaux , ADN ribosomique/analyse , Fabaceae/croissance et développement , Champignons/pathogénicité , Germination , Interactions hôte-microbes , Plant/croissance et développement
2.
Biomédica (Bogotá) ; 42(supl.2): 48-58, oct. 2022. tab, graf
Article Dans Espagnol | LILACS | ID: biblio-1403612

Résumé

Introducción. El síndrome respiratorio agudo grave causado por el nuevo coronavirus SARS-CoV-2 es causa de la emergencia sanitaria por la pandemia de COVID-19. Si bien el humano es el principal huésped vulnerable, en estudios experimentales y reportes de infección natural, se han encontrado casos de zoonosis inversa de SARS-CoV-2 en animales. Objetivo. Evaluar la infección natural por SARS-CoV-2 en gatos y perros de propietarios con diagnóstico de COVID-19 en el Valle de Aburrá, Antioquia, Colombia. Materiales y métodos. La circulación del SARS-CoV-2 se evaluó por RT-qPCR y RT-PCR en muestras de frotis nasofaríngeos y orofaríngeos de gatos y perros cuyos propietarios se encontraban dentro del periodo de los 14 días de aislamiento. Los casos positivos se verificaron amplificando fragmentos de los genes RdRp, N y E; se secuenció el gen RdRp y se analizó filogenéticamente. Resultados. De 80 animales evaluados, seis gatos y tres perros fueron casos confirmados de infección natural por SARS-CoV-2. Los animales no presentaron signos clínicos y sus propietarios, que padecían la infección, reportaron únicamente signos leves de la enfermedad sin complicaciones clínicas. En el análisis de una de las secuencias, se encontró un polimorfismo de un solo nucleótido (SNP) con un cambio en la posición 647, con sustitución del aminoácido serina (S) por una isoleucina (I). Los casos se presentaron en los municipios de Caldas, Medellín y Envigado. Conclusiones. Se infiere que la infección natural en los gatos y perros se asocia al contacto directo con un paciente con COVID-19. No obstante, no es posible determinar la virulencia del virus en este huésped, ni su capacidad de transmisión zoonótica o entre especie.


Introduction: The severe acute respiratory syndrome caused by the new coronavirus SARS-CoV-2 is the cause of the health emergency due to the COVID-19 pandemic. Although humans are the main susceptible host, experimental studies and reported cases of natural infection have evidenced scenarios of SARS-CoV-2 reverse zoonosis in animals. Objective: To evaluate the natural infection of SARS-CoV-2 in cats and dogs with owners diagnosed with COVID-19 in the Valle de Aburrá subregion in Antioquia, Colombia. Materials and methods. The circulation of SARS-CoV-2 was evaluated by RT-qPCR and RT-PCR in samples of nasopharyngeal and oropharyngeal smears from cats and dogs whose owners presented latent COVID-19 infection. Positive cases were verified through amplification of N, E and RdRp gene fragments; with the latter being sequenced and the phylogenetically analyzed. Results. From 80 tested animals, 6 cats and 3 dogs resulted positive for natural SARS-CoV-2 infection. These animals did not show any clinical signs; and their infected owners only reported mild signs of COVID-19, without clinical complications. Regarding analysis of one of the sequences, a single nucleotide polymorphism (SNP) was found, with a substitution in position 647, resulting in the change of the amino acid serine (S) for isoleucine (I). The cases occurred in the municipalities of Caldas, Medellín and Envigado. Conclusions. It is inferred that natural infection in cats and dogs is associated with direct contact with a positive COVID-19 patient.


Sujets)
Zoonoses , Infections à coronavirus , Phylogenèse , Syndrome respiratoire aigu sévère , Interactions hôte-microbes
3.
Rev. ADM ; 79(4): 218-223, jul.-ago. 2022. tab
Article Dans Espagnol | LILACS | ID: biblio-1396089

Résumé

Objetivo: actualizar la información sobre la disbiosis bacteriana oral y su efecto en enfermedades bucales. Material y métodos: se realizó una revisión bibliográfica detallada, donde la búsqueda de artículos comenzó desde el 2014 con trabajos de investigación relacionados con el tema. Se aplicaron palabras clave para facilitar y delimitar el tema. En los resultados obtenidos se observa información específica de disbiosis bacteriana y los problemas y enfermedades que causan en la cavidad bucal. Conclusión: la cavidad oral es un ecosistema muy complejo e interactivo donde se desarrollan variedades de hábitats que establecen relaciones entre los microorganismos en los distintos medios bucales. Por lo general, el cuerpo humano vive en simbiosis con dichas bacterias, esta relación hospedador-huésped es producto de años de evolución y convivencia para poder tolerar a dichas especies y por medio de años de investigación, determinar a los agentes patógenos y a los simbióticos, lo que permitirá en un futuro tener enfoques terapéuticos y científicos, para así solucionar, mejorar y evitar problemas relacionados con la salud (AU)


Objective: this review aimed to update the information on oral bacterial dysbiosis and its effect on oral diseases. Material and methods: a detailed literature review was performed, where the search for articles began in 2014 with research papers related to the topic. Keywords were applied to facilitate and delimit the topic. The results obtained show specific information on bacterial dysbiosis and the problems and diseases they cause in the oral cavity. Conclusion: the oral cavity is a very complex and interactive ecosystem where a variety of habitats develop and establish relationships between microorganisms in different oral environments. Generally, the human body lives in symbiosis with these bacteria, this host-guest relationship is the product of years of evolution and coexistence to be able to tolerate these species and through years of research to determine the pathogens and symbiotics, which will allow in the future to have therapeutic and scientific approaches, to solve, improve and avoid health-related problems (AU)


Sujets)
Humains , Infections bactériennes/complications , Dysbiose/étiologie , Maladies de la bouche/microbiologie , Bâtonnets à Gram positif/pathogénicité , Bâtonnets et coques aérobies à Gram négatif/pathogénicité , Plaque dentaire/microbiologie , Interactions hôte-microbes , Bouche/microbiologie
4.
Arq. Inst. Biol. (Online) ; 89: e00232021, 2022. tab, graf
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1416777

Résumé

Lime sulfur is one of the few products indicated to control Brevipalpus yothersi in Brazilian organic citrus orchards. Other strategies, such as the use of entomopathogenic fungi should be evaluated, and Lecanicillium muscarium is one of the basic choices for pest management. Knowledge of the interactions between lime sulfur and this entomopathogen is critical for developing control strategies. With this goal, it was conducted the toxicological characterization of lime sulfur to B. yothersi and the compatibility evaluation with L. muscarium. Finally, the effects of L. muscarium and lime sulfur mixtures on B. yothersi control were evaluated. Product evaluation for B. yothersi was done through direct and residual contact bioassay, and different concentrations of lime sulfur mixed in potato dextrose agar culture medium were used to evaluate compatibility with L. muscarium. Lime sulfur was effective against adults of B. yothersi and caused eggs unviability of up to 71.0%, at a dose of 80 L per 2,000 L of H2O. The lethal concentration (LC50 and LC99) of lime sulfur estimated for mite adults were 246.62 and 858.5 µg of sulfur per mL of H2O (ppm a.i.). Lime sulfur concentrations of 180 to 560 ppm a.i. showed promise for use in combination with L. muscarium. However, concentrations of 1,000 and 5,600 ppm significantly reduced colony size and the number of spores/colony. The mixture of 100 and 180 ppm a.i. of lime sulfur with L. muscarium (108 conidia·mL­1) was not able to reduce the lethal time of entomopathogen on B. yothersi.


Sujets)
Lutte biologique contre les nuisibles/méthodes , Citrus/parasitologie , Cordyceps , Mites (acariens) , Interactions hôte-microbes
5.
Braz. j. biol ; 82: 1-7, 2022. ilus, graf, tab
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1468441

Résumé

We report the discovery that the earwig predator Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) feed on Puccinia polysora Underw uredospore, the causal agent of Southern Rust of Corn (SRC), which is a primary disease affecting the maize crop in Brazil. We performed experiments in laboratory and greenhouse to test the effect of D. luteipes (1st/2nd and 3rd/4th instars, and adults) fungivory on the P. polysora uredospore concentration. All trials showed a significant reduction of the initial concentration of uredospore. There was a reduction in uredospore concentration with increase in number of D. luteipes feeding on them. We also tested the uredospore consumption by quantifying its percentage in the feces of D. luteipes. Nymphs of the 2nd, 4th instar and adults fed 88%, 85%, and 83.8% of the uredospore, respectively. For nymphs of the 3rd instar, the percentage of uredospore consumption (75.6%) was statistically significant compared with the other groups. In greenhouse experiment, at twenty-eight days after plant inoculation with 9.9 x 104 uredospores, the percentage of uredospore consumption was 81.7%. Our results confirmed the fungivory of D. luteipes on P. polysora uredospore. This is the first report of D. luteipes fungivory, which may play an important role in the biological control of P. polysora in corn.


Relatamos a descoberta de que o predador Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) se alimenta de uredosporos de Puccinia polysora Underw, o agente causal da ferrugem polisora que é uma doença primária que afeta a cultura do milho no Brasil. Realizamos experimentos em laboratório e em casa de vegetação para testar o efeito da fungivoria de D. luteipes (1º/2º e 3º/4º iìstares e adultos) sobre a concentração de uredosporos de P. polysora. Todos os ensaios mostraram uma redução significativa da concentração inicial de uredosporos. Houve uma redução na concentração de uredosporos com o aumento do número de D. luteipes alimentando-se deles. Também testamos o consumo de uredosporos quantificando sua porcentagem nas fezes de D. luteipes. Ninfas do 2º e 4º ínstar, assim como adultos, alimentaram-se de 88%, 85% e 83,8% dos uredosporos, respectivamente. Para ninfas do 3º ínstar, a porcentagem de consumo de uredosporos (75,6%) foi estatisticamente significativo em comparação com os outros grupos. No experimento em casa de vegetação, aos 28 dias após a inoculação das plantas com 9,9 x 104 uredosporos, a porcentagem de consumo de uredosporos foi de 81,7%. Nossos resultados confirmaram a fungivoria de D. luteipes em uredosporos de P. polysora. Este é o primeiro relato de fungivoria de D. luteipes, que pode ter papel importante no controle biológico de P. polysora em milho.


Sujets)
Animaux , Lutte biologique contre les nuisibles/méthodes , Champignons/pathogénicité , Interactions hôte-microbes , Neoptera , Pterygota/parasitologie , Zea mays/microbiologie
6.
Braz. oral res. (Online) ; 33(supl.1): e066, 2019.
Article Dans Anglais | LILACS | ID: biblio-1039322

Résumé

Abstract Considering the absence of predictable and effective therapeutic interventions for the treatment of peri-implantitis, scientific evidence concerning the host response profile around dental implants could be important for providing in the future a wider preventive and/or therapeutic window for this peri-implant lesion, indicating biomarkers that provide quantifiable measure of response to peri-implant therapy. Moreover, a better knowledge of pattern of host osteo-immunoinflammatory modulation in the presence of peri-implantitis could either benefit the early diagnostic of the disease or to cooperate to prognostic information related to the status of the peri-implant breakdown. Finally, new evidences concerning the host profile of modulators of inflammation and of osseous tissue metabolism around dental implants could explain the individual susceptibility for developing peri-implant lesions, identifying individuals or sites with increased risk for peri-implantitis. The focus of this chapter was, based on a systematically searched and critically reviewed literature, summarizing the existing knowledge in the scientific research concerning the host osteo-immunoinflammatory response to the microbiological challenge related to periimplantitis.


Sujets)
Humains , Implants dentaires , Péri-implantite/immunologie , Résorption osseuse/immunologie , Marqueurs biologiques , Interleukines/immunologie , Matrix metalloproteinases/immunologie , Péri-implantite/microbiologie , Interactions hôte-microbes/immunologie
7.
Rev. Soc. Bras. Med. Trop ; 52: e20180001, 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1041589

Résumé

Abstract INTRODUCTION: Studies have demonstrated that pathogens react to the harsh conditions in human tissues by inducing mechanisms that promote survival. METHODS: Persistence and biofilm-forming ability were evaluated during stress conditions that mimic those in the host. RESULTS: Carbon-source availability had a positive effect on Staphylococcus epidermidis RP62A adhesion during hypoxia, accompanied by a decrease in pH. In contrast, iron limitation led to decreased surface-adherent biomass, accompanied by an increase medium acidification and lactate levels. Interestingly, iron starvation and hypoxia induced persister cells in planktonic culture. CONCLUSIONS: These findings highlight the role of host stress in the virulence of S. epidermidis.


Sujets)
Humains , Staphylococcus epidermidis/physiologie , Virulence/physiologie , Biofilms/croissance et développement , Milieux de culture/pharmacologie , Interactions hôte-microbes/physiologie , Staphylococcus epidermidis/effets des médicaments et des substances chimiques , Staphylococcus epidermidis/pathogénicité , Stress physiologique , Virulence/effets des médicaments et des substances chimiques , Dosage biologique , Interactions hôte-microbes/effets des médicaments et des substances chimiques
8.
Protein & Cell ; (12): 462-473, 2018.
Article Dans Anglais | WPRIM | ID: wpr-757960

Résumé

Fecal microbiota transplantation (FMT) has become a research focus of biomedicine and clinical medicine in recent years. The clinical response from FMT for different diseases provided evidence for microbiota-host interactions associated with various disorders, including Clostridium difficile infection, inflammatory bowel disease, diabetes mellitus, cancer, liver cirrhosis, gut-brain disease and others. To discuss the experiences of using microbes to treat human diseases from ancient China to current era should be important in moving standardized FMT forward and achieving a better future. Here, we review the changing concept of microbiota transplantation from FMT to selective microbiota transplantation, methodology development of FMT and step-up FMT strategy based on literature and state experts' perspectives.


Sujets)
Humains , Infections à Clostridium , Thérapeutique , Transplantation de microbiote fécal , Méthodes , Normes de référence , Interactions hôte-microbes , Maladies inflammatoires intestinales , Thérapeutique , Maladies métaboliques , Thérapeutique
9.
Braz. j. microbiol ; 45(1): 163-173, 2014. tab, graf
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1469601

Résumé

Investigating the endophytic bacterial community in special moss species is fundamental to understanding the microbial-plant interactions and discovering the bacteria with stresses tolerance. Thus, the community structure of endophytic bacteria in the xerophilous moss Grimmia montana were estimated using a 16S rDNA library and traditional cultivation methods. In total, 212 sequences derived from the 16S rDNA library were used to assess the bacterial diversity. Sequence alignment showed that the endophytes were assigned to 54 genera in 4 phyla (Proteobacteria, Firmicutes, Actinobacteria and Cytophaga/Flexibacter/Bacteroids). Of them, the dominant phyla were Proteobacteria (45.9%) and Firmicutes (27.6%), the most abundant genera included Acinetobacter, Aeromonas, Enterobacter, Leclercia, Microvirga, Pseudomonas, Rhizobium, Planococcus, Paenisporosarcina and Planomicrobium. In addition, a total of 14 species belonging to 8 genera in 3 phyla (Proteobacteria, Firmicutes, Actinobacteria) were isolated, Curtobacterium, Massilia, Pseudomonas and Sphingomonas were the dominant genera. Although some of the genera isolated were inconsistent with those detected by molecular method, both of two methods proved that many different endophytic bacteria coexist in G. montana. According to the potential functional analyses of these bacteria, some species are known to have possible beneficial effects on hosts, but whether this is the case in G. montana needs to be confirmed.


Sujets)
Bryopsida/microbiologie , Endophytes , Interactions hôte-microbes , Microbiote
SÉLECTION CITATIONS
Détails de la recherche