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1.
Methods Mol Biol ; 2852: 181-196, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39235745

RESUMO

This chapter introduces protocols for culturing and maintaining Dictyostelium discoideum and methods for conducting virulence assays in this organism to study bacterial pathogenicity. It outlines advanced techniques, such as automated microscopy and flow cytometry, for detailed cellular analysis and traditional microbiological approaches. These comprehensive protocols will enable researchers to probe the virulence factors of pathogens like Klebsiella pneumoniae and to elucidate the details of host-pathogen interactions within a cost-effective and adaptable laboratory framework.


Assuntos
Dictyostelium , Citometria de Fluxo , Klebsiella pneumoniae , Dictyostelium/microbiologia , Citometria de Fluxo/métodos , Klebsiella pneumoniae/patogenicidade , Fagocitose , Virulência , Interações Hospedeiro-Patógeno , Microscopia/métodos
2.
Semina cienc. biol. saude ; 45(2): 45-56, jul./dez. 2024. tab; ilus
Artigo em Inglês | LILACS | ID: biblio-1554899

RESUMO

Enteroparasitosis are diseases caused by parasitic agents present in the environment and in the gastrointestinal tract of living beings. In addition, they are still considered neglected diseases, but of great importance for public health, especially when they are related to secondary infections and currently their co-infection profile with COVID-19. The interaction of protozoa and/or helminths with the SARS-CoV-2 virus is timely and its signs and symptoms are confused with other pathogen relationships. In this way, this study aims to correlate the incidence of enteroparasitosis and COVID-19, in the pandemic period from 2020 to April 2022. This is a documentary and exploratory study of secondary data from laboratory tests of patients who were treated and diagnosed with COVID-19 and enteroparasitosis at Hospital Doutor Cloves Bezerra Cavalcante, Municipal Hospital of Bananeiras, Paraíba, Brazil. In the analysis of the database, a significant increase of approximately 48.85% in the incidence of COVID-19 cases from 2020 to 2021 stands out, remaining high until 2022. In contrast, cases of enteroparasites peaked at 48.74% in 2021, followed by an average reduction of 23.12%, with a deviation of 1.49%, in relation to the years 2020 and 2022. It was concluded that COVID-19 is predominantly associated with an increase in secondary infections, highlighting the crucial need to promote health education, improve basic sanitation and guarantee access to health services as essential components in combating the increase in parasitic infections, especially those related to viral pathologies.


As enteroparasitoses são enfermidades originadas por agentes parasitários presentes no meio ambiente e no trato gastrointestinal dos seres vivos. Ademais, ainda são consideradas doenças negligenciadas, porém de grande importância para a saúde pública, em especial, quando estão relacionadas com infecções secundárias e atualmente seu perfil de coinfecção com a COVID-19. A interação de protozoários e/ou helmintos com o vírus SARS-CoV-2 é oportuna e seus sinais e sintomas são confundidos com outras relações de patógenos. Desta maneira, este estudo visa correlacionar a incidência de enteroparasitoses e COVID-19, no período pandêmico de 2020 a abril de 2022. Trata--se de uma pesquisa documental e exploratória, de dados secundários dos exames laboratoriais de pacientes que foram atendidos e diagnosticados com COVID-19 e enteroparasitoses no Hospital Doutor Cloves Bezerra Cavalcante, Hospital Municipal de Bananeiras, Paraíba, Brasil. Na análise da base de dados, destaca-se um aumento significativo de aproximadamente 48,85% na incidência de casos de COVID-19 de 2020 a 2021, mantendo-se elevado até 2022. Em contraste, os casos de enteroparasitas atingiram um pico de 48,74% em 2021, seguido por uma redução média de 23,12%, com um desvio de 1,49%, em relação aos anos de 2020 e 2022. Conclui-se que a COVID-19 está predominantemente associada ao aumento de infecções secundárias, destacando a necessidade crucial de promover a educação em saúde, melhorar o saneamento básico e garantir o acesso aos serviços de saúde como componentes essenciais no combate ao aumento de infecções parasitárias, especialmente aquelas relacionadas a patologias virais.


Assuntos
Humanos , Masculino , Feminino
3.
Arch. argent. pediatr ; 122(5): e202310271, oct. 2024. tab, graf
Artigo em Inglês, Espanhol | LILACS, BINACIS | ID: biblio-1571785

RESUMO

Cryptosporidium spp. es un protozoario productor de diarrea. Los pacientes inmunocomprometidos pueden desarrollar formas clínicas graves y persistentes. Se describen las características de pacientes con enfermedad de base asociada a inmunosupresión (EAI) con infección por Cryptosporidium spp. (IC) atendidos en un hospital pediátrico referencial de Argentina entre los años 2018 y 2023. Se analizaron datos demográficos, EAI, características de la diarrea y coinfecciones. Se incluyeron 30 pacientes con EAI e IC. La mayoría registró trasplante de órgano sólido, neoplasia hematológica e inmunodeficiencia primaria. Dieciocho presentaron diarrea persistente al momento del diagnóstico. Seis pacientes registraron coinfecciones. Se debe considerar la criptosporidiosis en el diagnóstico diferencial de enfermedad diarreica aguda o persistente en niños con distintos tipos de EAI, como el trasplante de órgano sólido, neoplasias hematológicas e inmunodeficiencias primarias.


Cryptosporidium spp. is a diarrhea-causing protozoan. Immunocompromised patients may develop severe and persistent clinical forms. Here we describe the characteristics of patients with an underlying disease associated with immunosuppression (DAI) and Cryptosporidium spp. infection seen at a referral children's hospital in Argentina between 2018 and 2023. Demographic data, DAI, diarrhea characteristics, and co-infections were analyzed. A total of 30 patients with DAI and cryptosporidiosis were included. Most of them had undergone a solid organ transplant, had a hematologic neoplasm, or primary immunodeficiency. Persistent diarrhea was observed in 18 patients at the time of diagnosis. Co-infections were recorded in 6 patients. Cryptosporidiosis should be considered in the differential diagnosis of acute or persistent diarrhea in children with different types of DAI, such as solid organ transplant, hematologic neoplasms, and primary immunodeficiencies.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Hospedeiro Imunocomprometido , Criptosporidiose/diagnóstico , Criptosporidiose/epidemiologia , Hospitais Pediátricos/estatística & dados numéricos , Argentina/epidemiologia , Estudos Retrospectivos , Diarreia/etiologia , Diarreia/parasitologia , Diarreia/epidemiologia , Coinfecção/epidemiologia
4.
J Virol ; : e0036124, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404263

RESUMO

Chloroviruses exhibit a close relationship with their hosts with the phenotypic aspect of their ability to form lytic plaques having primarily guided the taxonomy. However, with the isolation of viruses that are only able to complete their replication cycle in one strain of Chlorella variabilis, systematic challenges emerged. In this study, we described the genomic features of 53 new chlorovirus isolates and used them to elucidate part of the evolutionary history and taxonomy of this clade. Our analysis revealed new chloroviruses with the largest genomes to date (>400 kbp) and indicated that four genomic features are statistically different in the viruses that only infect the Syngen 2-3 strain of C. variabilis (OSy viruses). We found large regions of dissimilarity in the genomes of viruses PBCV-1 and OSy-NE5 when compared with the other genomes. These regions contained genes related to the interaction with the host cell machinery and viral capsid proteins, which provided insights into the evolution of the replicative and structural modules in these giant viruses. Phylogenetic analysis using hallmark genes of Nucleocytoviricota revealed that OSy-viruses evolved from the NC64A-viruses, possibly emerging as a result of the strict relationship with their hosts. Merging phylogenetics and nucleotide identity analyses, we propose strategies to demarcate viral species, resulting in seven new species of chloroviruses. Collectively, our results show how genomic data can be used as lines of evidence to demarcate viral species. Using the chloroviruses as a case study, we expect that similar initiatives will emerge using the basis exhibited here.IMPORTANCEChloroviruses are a group of giant viruses with long dsDNA genomes that infect different species of Chlorella-like green algae. They are host-specific, and some isolates can only replicate within a single strain of Chlorella variabilis. The genomics of these viruses is still poorly explored, and the characterization of new isolates provides important data on their genetic diversity and evolution. In this work, we describe 53 new chlorovirus genomes, including many isolated from alkaline lakes for the first time. Through comparative genomics and molecular phylogeny, we provide evidence of genomic gigantism in chloroviruses and show that a subset of viruses became highly specific for their hosts at a particular point in evolutionary history. We propose criteria to demarcate species of chloroviruses, paving the way for an update in the taxonomy of other groups of viruses. This study is a new and important piece in the complex puzzle of giant algal viruses.

5.
FEMS Microbiol Ecol ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39363207

RESUMO

Conceptual biogeographic frameworks have proposed that the relative contribution of environmental and geographical factors on microbial distribution depends on several characteristics of the habitat (e.g. environmental heterogeneity, species diversity, proportion of specialist/generalist taxa), all of them defining the degree of habitat specificity, but few experimental demonstrations exist. Here, we aimed to determine the effect of habitat specificity on bacterial biogeographic patterns and assembly processes in benthic coastal ecosystems of the Southern Ocean (Patagonia, Falkland/Malvinas, Kerguelen, South Georgia and King George Islands), using 16S rRNA gene metabarcoding. The gradient of habitat specificity resulted from a 'natural experimental design' provided by the Abatus sea urchin model, from the sediment (least specific habitat) to the intestinal tissue (most specific habitat). The phylogenetic composition of the bacterial communities showed a clear differentiation by site, driven by a similar contribution of geographic and environmental distances. However, the strength of this biogeographic pattern decreased with increasing habitat specificity: sediment communities showed stronger geographic and environmental divergence compared to gut tissue. The proportion of stochastic and deterministic processes contributing to bacterial assembly varied according to the geographic scale and the habitat specificity level. For instance, an increased contribution of dispersal limitation was observed in gut tissue habitat. Our results underscore the importance of considering different habitats with contrasting levels of specificity to better understand bacterial biogeography and assembly processes over oceanographic scales.

6.
Arch Insect Biochem Physiol ; 117(2): e22154, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39397367

RESUMO

The English grain aphid, Sitobion avenae, is a significant agricultural pest affecting wheat, barley, and oats. In Chile, the most prevalent and persistent clone (superclone) of S. avenae harbors the facultative endosymbiont bacterium Regiella insecticola. To determine the role of this bacterium in the reproductive success of this superclone, the presence of R. insecticola was manipulated to assess its impact on (1) the reproductive performance of this clone on two host plant species (wheat and barley), (2) the production of winged morphs, (3) changes in the insects' proteomic profiles, and (4) the root/shoot ratio of plant. It was found that the reproductive performance of this S. avenae superclone varied across host plants, depending on the presence of the facultative bacterial endosymbiont. Aphids infected with R. insecticola showed higher reproductive success on wheat, while the opposite effect was observed on barley. Aphid biomass was greater when infected with R. insecticola, particularly on barley. Additionally, aphids harboring R. insecticola exhibited a higher proportion of winged individuals on both host plants. Protein regulation in aphids on wheat was lower compared to those on barley. A higher root/shoot biomass ratio was observed in wheat plants compared to barley when infested by R. insecticola-infected aphid. Thus, R. insecticola significantly influences the reproductive performance and proteomic profile of a S. avenae superclone, with these effects shaped by the host plant. This suggests that the interaction between the host plant and the facultative endosymbiont contributes to the ecological success of this superclone.


Assuntos
Afídeos , Hordeum , Reprodução , Simbiose , Triticum , Animais , Afídeos/microbiologia , Afídeos/fisiologia , Triticum/microbiologia , Hordeum/microbiologia , Proteoma/metabolismo , Proteômica , Proteínas de Insetos/metabolismo , Enterobacteriaceae , Chile
7.
Curr Top Membr ; 94: 133-155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39370205

RESUMO

Toxoplasma gondii, the causative agent of toxoplasmosis, is widely distributed. This protozoan parasite is one of the best adapted, being able to infect innumerous species of animals and different types of cells. This chapter reviews current literature on extracellular vesicles secreted by T. gondii and by its hosts. The topics describe the life cycle and transmission (1); toxoplasmosis epidemiology (2); laboratorial diagnosis approach (3); The T. gondii interaction with extracellular vesicles and miRNAs (4); and the perspectives on T. gondii infection. Each topic emphases the host immune responses to the parasite antigens and the interaction with the extracellular vesicles and miRNAs.


Assuntos
Vesículas Extracelulares , Interações Hospedeiro-Parasita , Toxoplasma , Toxoplasmose , Vesículas Extracelulares/metabolismo , Toxoplasma/metabolismo , Humanos , Animais , Toxoplasmose/metabolismo , Toxoplasmose/parasitologia , Toxoplasmose/imunologia , MicroRNAs/metabolismo , MicroRNAs/genética
8.
An. bras. dermatol ; An. bras. dermatol;99(5): 706-720, Sept.-Oct. 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1573803

RESUMO

Abstract Prurigo is a reactive, hyperplastic skin condition characterized by pruritic papules, plaques, and/or nodules. The temporal classification includes acute/subacute and chronic disease (≥ 6 weeks), with different clinical variants, synonymies, and underlying etiological factors. The immunology of chronic prurigo shows similarities with atopic dermatitis due to the involvement of IL-4 and IL-13, IL-22, and IL-31. Treatment includes antihistamines, topical steroids, dupilumab, and JAK inhibitors. Several conditions manifest clinically as prurigo-like lesions, and the correct clinical diagnosis must precede correct treatment. Furthermore, chronic prurigos represent a recalcitrant and distressing dermatosis, and at least 50% of these patients have atopic diathesis, the treatment of which may induce adverse effects, especially in the elderly. The quality of life is significantly compromised, and topical treatments are often unable to control symptoms and skin lesions. Systemic immunosuppressants, immunobiologicals, and JAK inhibitors, despite the cost and potential adverse effects, may be necessary to achieve clinical improvement and quality of life. This manuscript reviews the main types of prurigo, associated diseases, their immunological bases, diagnosis, and treatment.

9.
Arq. ciências saúde UNIPAR ; 28(2): 82-99, 20240000.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1572323

RESUMO

Although research has investigated the host-parasite relationship in Strongyloides venezuelensis infection in the scope of its immunological implications, the morphological consequences of this response for the host organism are yet to be explored. Our objective was to perform an organ morphometric analysis in Wistar rats infected with the intestinal parasite Strongyloides venezuelensis compared with infected rats treated with ivermectin. Twenty-six animals composed three groups: control (non-infected), infected (infected with 2,000 Strongyloides venezuelensis larvae), and infected treated (infected with 2,000 Strongyloides venezuelensis larvae and treated with ivermectin). All rodents were killed 21 days after infection and morphometric analysis of different organs was performed. The results showed significantly higher body and fecal weight in the infected-treated group. The weight of the small intestine increased considerably in the infected group and decreased in the infected-treated group. Pancreas, right kidney, and heart volume increased in the infected group compared with the control group. Despite treatment, the volumes of the stomach, brain, and left kidney increased in both the infected groups compared with the control group indicating the possibility of non-reversible host morphological adaptations. S. venezuelensis infection can augment both, volume and weight of organs ­ not necessarily related to the Strongyloides expulsion process ­ even if the acute infection had been in remission. A potential explanation for these host adaptations, including the occurrence of organ plasticity, are briefly discussed. The following steps encompass a histological analysis to verify the occurrence of hypertrophy/hyperplasia and observe if such morphological alterations remain after infection.


Embora pesquisas tenham investigado a relação parasita-hospedeiro na infecção por Strongyloides venezuelensis no âmbito de suas implicações imunológicas, as consequências morfológicas dessa resposta para o organismo hospedeiro ainda precisam ser exploradas. Nosso objetivo foi realizar uma análise morfométrica de órgãos em ratos Wistar infectados com o parasito intestinal Strongyloides venezuelensis em comparação com ratos infectados tratados com ivermectina. Vinte e seis animais compuseram três grupos: controle (não infectados), infectados (infectados com 2.000 larvas de Strongyloides venezuelensis) e tratados infectados (infectados com 2.000 larvas de Strongyloides venezuelensis e tratados com ivermectina). Todos os roedores foram sacrificados 21 dias após a infecção e a análise morfométrica de diferentes órgãos foi realizada. Os resultados mostraram peso corporal e fecal significativamente maior no grupo tratado infectado. O peso do intestino delgado aumentou consideravelmente no grupo infectado e diminuiu no grupo infectado tratado. O volume do pâncreas, rim direito e coração aumentou no grupo infectado em comparação com o grupo controle. Apesar do tratamento, os volumes do estômago, cérebro e rim esquerdo aumentaram em ambos os grupos infectados em comparação com o grupo controle, indicando a possibilidade de adaptações morfológicas não reversíveis do hospedeiro. A infecção por S. venezuelensis pode aumentar tanto o volume quanto o peso dos órgãos ­ não necessariamente relacionado ao processo de expulsão de Strongyloides ­ mesmo que a infecção aguda estivesse em remissão. Uma possível explicação para essas adaptações do hospedeiro, incluindo a ocorrência de plasticidade de órgãos, é brevemente discutida. As etapas a seguir compreendem uma análise histológica para verificar a ocorrência de hipertrofia/hiperplasia e observar se tais alterações morfológicas permanecem após a infecção.


Aunque se ha investigado la relación parásito-hospedador en la infección por Strongyloides venezuelensis en el contexto de sus implicaciones inmunológicas, aún no se han explorado las consecuencias morfológicas de esta respuesta para el organismo hospedador. Nuestro objetivo fue realizar un análisis morfométrico de los órganos de ratas Wistar infectadas con el parásito intestinal Strongyloides venezuelensis en comparación con ratas infectadas tratadas con ivermectina. Veintiséis animales se distribuyeron en tres grupos: control (no infectados), infectados (infectados con 2000 larvas de Strongyloides venezuelensis) e infectados tratados (infectados con 2000 larvas de Strongyloides venezuelensis y tratados con ivermectina). Todos los roedores fueron sacrificados 21 días después de la infección y se realizaron análisis morfométricos de diferentes órganos. Los resultados mostraron pesos corporales y fecales significativamente superiores en el grupo infectado-tratado. El peso del intestino delgado aumentó considerablemente en el grupo derecho y el corazón aumentó en el grupo infectado en comparación con el grupo de control. A pesar del tratamiento, los volúmenes del estómago, el cerebro y el riñón izquierdo aumentaron en ambos grupos infectados en comparación con el grupo de control, lo que indica la posibilidad de adaptaciones morfológicas no reversibles del hospedador. La infección por S. venezuelensis puede aumentar tanto el volumen como el peso de los órganos, que no están necesariamente relacionados con el proceso de expulsión de Strongyloides, incluso si la infección aguda estaba en remisión. Se debate brevemente una posible explicación de estas adaptaciones del hospedador, incluida la ocurrencia de plasticidad de los órganos. Los pasos siguientes comprenden un análisis histológico para verificar la aparición de hipertrofia o hiperplasia y observar si estas alteraciones morfológicas persisten tras la infección.

10.
Parasitol Res ; 123(9): 328, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297998

RESUMO

This study examined the metrics of the macroparasite community in fishes from the Jaguaribe River basin, state of Ceará, before and after receiving water from the São Francisco River in Northeastern Brazil. This research assessed the association of environmental factors (water parameters) and the traits of 30 fish species on the parasite richness and abundance across space (river course) and time (seasons, pre- and post-transposition periods). Generalized linear models reveal associations between parasite metrics and host traits, water parameters, and river sub-basin. Host size and body condition positively correlated with parasite richness and abundance, while reproductive phase was negatively related. Water quality impacted ecto- and endoparasites differently, with seasonal and sub-basins variations and differences among sub-basins. The general models also indicate that the period is a significant variable, where parasite richness decreases while abundance increases in the post-transposition period. This study underscores the importance of considering diverse environmental and host variables for understanding parasite dynamics in river ecosystems. These findings could lead to valuable insights for ecosystem management and conservation, elucidating the potential consequences of environmental alterations on parasite-host interactions and ecosystem health.


Assuntos
Biodiversidade , Doenças dos Peixes , Peixes , Parasitos , Rios , Animais , Brasil , Rios/parasitologia , Peixes/parasitologia , Parasitos/classificação , Parasitos/isolamento & purificação , Doenças dos Peixes/parasitologia , Estações do Ano , Ecossistema , Doenças Parasitárias em Animais/parasitologia , Doenças Parasitárias em Animais/epidemiologia
11.
Sci Rep ; 14(1): 21518, 2024 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277613

RESUMO

Advances in omics technologies have enabled the in-depth study of microbial communities and their metabolic profiles from all environments. Here metagenomes were sampled from piranha (Serrasalmus rhombeus) and from river water from the Rio São Benedito (Amazon Basin). Shotgun metagenome sequencing was used to explore diversity and to test whether fish microbiomes are a good proxy for river microbiome studies. The results showed that the fish microbiomes were not significantly different from the river water microbiomes at higher taxonomic ranks. However, at the genus level, fish microbiome alpha diversity decreased, and beta diversity increased. This result repeated for functional gene abundances associated with specific metabolic categories (SEED level 3). A clear delineation between water and fish was seen for beta diversity. The piranha microbiome provides a good and representative subset of its river water microbiome. Variations seen in beta biodiversity were expected and can be explained by temporal variations in the fish microbiome in response to stronger selective forces on its biodiversity. Metagenome assembled genomes construction was better from the fish samples. This study has revealed that the microbiome of a piranha tells us a lot about its river water microbiome and function.


Assuntos
Biodiversidade , Microbioma Gastrointestinal , Rios , Rios/microbiologia , Microbioma Gastrointestinal/genética , Animais , Metagenoma , Metagenômica/métodos , Microbiologia da Água , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação
12.
Int J Pharm ; 666: 124740, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39341387

RESUMO

Resistant M. tuberculosis strains threaten pulmonary tuberculosis (P-TB) control since they limit drug options. Drug repositioning and new development strategies are urgently required to overcome resistance. Studies have already shown the beneficial role of the oral antidiabetic metformin as an anti-tuberculosis adjuvant drug. This work aimed to develop an inhalatory dry powder co-formulation of metformin and moxifloxacin to figure out a future option for P-TB treatment. Pre-formulation evaluations indicated the physicochemical compatibility of constituents, demonstrating powder crystallinity and acceptable drug content. Eight moxifloxacin-metformin dry powder formulations were produced by spray drying, and solid-state characterizations showed partial amorphization, ascribed to moxifloxacin. Four formulations containing L-leucine exhibited micromeritic and in vitro deposition profiles indicating pulmonary delivery suitability, like spherical and corrugated particle surface, geometric diameters < 5 µm, high emitted doses (>85 %), and mass median aerodynamic diameters between 1-5 µm. The use of a second spray dryer model further optimized the aerodynamic properties and yield of the best formulation, demonstrating the influence of the equipment used on the product obtained. Moreover, the final formulation showed high in vitro cell tolerability and characteristics in permeability studies indicative of good drug retention in the lungs.

13.
J Virol ; 98(10): e0104524, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39225468

RESUMO

In the context of the virosphere, viral particles can compete for host cells. In this scenario, some viruses block the entry of exogenous virions upon infecting a cell, a phenomenon known as superinfection inhibition. The molecular mechanisms associated with superinfection inhibition vary depending on the viral species and the host, but generally, blocking superinfection ensures the genetic supremacy of the virus's progeny that first infects the cell. Giant amoeba-infecting viruses have attracted the scientific community's attention due to the complexity of their particles and genomes. However, there are no studies on the occurrence of superinfection and its inhibition induced by giant viruses. This study shows that mimivirus, moumouvirus, and megavirus, exhibit different strategies related to the infection of Acanthamoeba. For the first time, we have reported that mimivirus and moumouvirus induce superinfection inhibition in amoebas. Interestingly, megaviruses do not exhibit this ability, allowing continuous entry of exogenous virions into infected amoebas. Our investigation into the mechanisms behind superinfection blockage reveals that mimivirus and moumouvirus inhibit amoebic phagocytosis, leading to significant changes in the morphology and activity of the host cells. In contrast, megavirus-infected amoebas continue incorporating newly formed virions, negatively affecting the available viral progeny. This effect, however, is reversible with chemical inhibition of phagocytosis. This work contributes to the understanding of superinfection and its inhibition in mimivirus, moumouvirus, and megavirus, demonstrating that despite their evolutionary relatedness, these viruses exhibit profound differences in their interactions with their hosts.IMPORTANCESome viruses block the entry of new virions upon infecting a cell, a phenomenon known as superinfection inhibition. Superinfection inhibition in giant viruses has yet to be studied. This study reveals that even closely related viruses, such as mimivirus, moumouvirus, and megavirus, have different infection strategies for Acanthamoeba. For the first time, we have reported that mimivirus and moumouvirus induce superinfection inhibition in amoebas. In contrast, megaviruses do not exhibit this ability, allowing continuous entry of exogenous virions into infected amoebas. Our investigation shows that mimivirus and moumouvirus inhibit amoebic phagocytosis, causing significant changes in host cell morphology and activity. Megavirus-infected amoebas, however, continue incorporating newly formed viruses, affecting viral progeny. This research enhances our understanding of superinfection inhibition in these viruses, highlighting their differences in host interactions.


Assuntos
Acanthamoeba , Vírus Gigantes , Mimiviridae , Fagocitose , Superinfecção , Superinfecção/virologia , Superinfecção/imunologia , Acanthamoeba/virologia , Vírus Gigantes/fisiologia , Vírus Gigantes/genética , Mimiviridae/fisiologia , Mimiviridae/genética , Internalização do Vírus , Vírion , Regulação para Baixo
14.
Microb Pathog ; 196: 106951, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39299555

RESUMO

Paracoccidioidomycosis (PCM) is a systemic granulomatous mycosis prevalent in individuals who carry out rural activities. Its etiological agent is a thermodimorphic fungus belonging to the genus; Paracoccidioides spp. Seven species of this fungus are known: Paracoccidioides brasiliensis, Paracoccidioides lutzii, Paracoccidioides americana, Paracoccidioides restrepiensis, Paracoccidioides venezuelensis, Paracoccidioides loboi and Paracoccidioides ceti. For a long time, Paracoccidioides brasiliensis was attributed as the only causal agent of this mycosis. What is known about adhesins, virulence, escape mechanisms and fungal involvement with the host's immune system is correlated with the species Paracoccidioides brasiliensis. Interactions between Paracoccidioides spp. and the host are complex and dynamic. The fungus needs nutrients for its needs and must adapt to a hostile environment, evading the host's immune system, thus enabling the development of the infectious process. On the other hand, the host's immune system recognizes Paracoccidioides spp. and employs all protective mechanisms to prevent fungal growth and consequently tissue invasion. Knowing this, understanding how Paracoccidioides spp. escapes the host's immune system, can help to understand the pathogenic mechanisms related to the development of the disease and, therefore, in the design of new specific treatment strategies. In this review we discuss these mechanisms and what are the adhesion molecules of Paracoccidioides spp. uses to escape the hostile environment imposed by the host's defense mechanisms; finally, we suggest how to neutralize them with new antifungal therapies.


Assuntos
Interações Hospedeiro-Patógeno , Paracoccidioides , Paracoccidioidomicose , Paracoccidioides/patogenicidade , Paracoccidioides/imunologia , Paracoccidioidomicose/microbiologia , Paracoccidioidomicose/imunologia , Humanos , Virulência , Evasão da Resposta Imune , Animais
15.
J Econ Entomol ; 117(5): 2135-2142, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39255407

RESUMO

Rachiplusia nu Guenée is a polyphagous species able to develop on several cultivated and non-cultivated host plants. However, basic life history information about this pest on hosts is scarce. In this study, R. nu larvae did not survive on leaves of non-Bt corn, wheat, Bt cotton that expresses proteins Cry1Ac+Cry2Ab2 or on Intacta2 Xtend soybean that expresses the Cry1A.105/Cry2Ab2/Cry1Ac proteins. Rachiplusia nu showed a viable egg-to-adult biological cycle (54%-66.3%) on non-Bt soybean, sunflower, canola, vetch, Persian clover, alfalfa, bean, and forage turnip hosts, similar to larvae raised on the artificial diet. In addition, R. nu was unable to complete larval development on non-Bt cotton, and only 45.2% of R. nu larvae reached the pupal stage when fed leaves of intacta RR2 PRO soybean that expresses the Cry1Ac protein. Larval and pupal mass of surviving insects on Cry1Ac soybean leaves were also lower (larval: 0.104 g; pupal: 0.099 g) in relation to other food sources (larval: 0.165-0.189 g; pupal: 0.173-0.192 g). The total fecundity of R. nu on Cry1Ac soybean leaves was ≈65% lower in relation to other food sources. This fact caused ≈60% the net reproductive rate (Ro) and intrinsic rate of increase (rm) when compared to other food sources. Our findings indicate that the Cry1Ac soybean negatively affects the biological parameters of R. nu. Non-Bt soybean, sunflower, canola, vetch, Persian clover, alfalfa, bean, and forage turnip are viable food sources for the survival and development of R. nu.


Assuntos
Toxinas de Bacillus thuringiensis , Endotoxinas , Proteínas Hemolisinas , Larva , Mariposas , Animais , Mariposas/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Dieta , Feminino , Pupa/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Proteínas de Bactérias , Masculino , Tábuas de Vida , Características de História de Vida
16.
Clin Transl Oncol ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39231914

RESUMO

OBJECTIVE: Chronic graft-versus-host disease (cGVHD) is a significant complication following allogenic hematopoietic stem cell transplantation, often necessitating therapeutic interventions such as rituximab (RTX) and cyclosporin A (CsA). This study aims to elucidate the mechanisms by which RTX and CsA jointly address B-cell dysregulation in cGVHD, providing a theoretical foundation and scientific rationale for the treatment and prognostic evaluation of this condition. METHODS: A total of 30 cGVHD mouse models were established by subjecting recipient mice to total body irradiation followed by injection of a mixed suspension of bone marrow cells and splenocytes from donor mice. From Day 2 to Day 29 post-model establishment, the mice received subcutaneous administration of RTX and CsA. Throughout the study, body weight, clinical cGVHD scores, and survival rates were monitored. Blood samples were collected via the orbital venous plexus. Serum levels of B-cell activating factor (BAFF) and pro-inflammatory factors were measured using enzyme-linked immunosorbent assay (ELISA), and the ratio of regulatory B cells (Bregs) in the blood sample was assessed via flow cytometry. RESULTS: Mice with cGVHD exhibited a 14.5% decrease in body weight, elevated clinical scores, and more severe symptoms compared to the control group. Notably, all mice in both the cGVHD and control groups survived until the conclusion of the study. Induction of cGVHD resulted in B-cell dysregulation, evidenced by elevated serum BAFF levels and a decreased proportion of Bregs. However, treatment with RTX combined with CsA ameliorated B-cell dysregulation and significantly reduced serum levels of pro-inflammatory factors in cGVHD mice, with decreases of 39.78% in TNF-α and 37.89% in IL-6. CONCLUSION: The combination of RTX and CsA effectively mitigates B-cell dysregulation in cGVHD, thereby reducing the severity and progression of the disease.

17.
Data Brief ; 56: 110857, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39281012

RESUMO

This dataset results from controlled experiments that assess the tolerance of Urochloa spp. and Megathyrsus maximus grasses to nymphal and adult spittlebug damage, particularly from Aeneolamia varia, which significantly impacts forage production in Neotropical regions. Data were collected under standardized conditions using high-throughput phenotyping methods, integrating image-capture techniques and analyses to ensure precise and consistent data acquisition. The dataset serves as a foundational resource for developing and validating computer vision models aimed at automated phenotyping, enabling accurate and high-throughput assessment of plant tolerance to spittlebug damage. Researchers can use the dataset to benchmark and compare different methodologies for plant damage assessment, fostering standardization and reproducibility in phenotyping studies.

18.
Ecology ; 105(10): e4394, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39234933

RESUMO

Parasite-host systems are a good study model for answering ecological and evolutionary questions. In this regard, mistletoes have been increasingly studied in recent decades in both temperate and tropical zones. The genus Phoradendron is a group of American mistletoes that has been studied from different evolutionary and ecological approaches as a model of parasite-host systems. Currently, however, no systematic compilation of the plant species parasitized by these mistletoes is available. To address this issue, we conducted a thorough search and compilation of interactions between mistletoe species of the genus Phoradendron and their hosts. This involved consulting multiple sources, including monographs, digitized herbaria material, and scientific publications. Additionally, we incorporated information regarding the presence records of Phoradendron from the most authoritative databases at the national, continental, and global levels. This process yielded a comprehensive dataset consisting of two independent tables, offering information on the interactions and occurrences of Phoradendron throughout its distribution range in the Americas. The dataset includes the interactions between 159 mistletoe species and 118 hosts at the family level, 379 hosts at the genus level, and 544 hosts at the species level, totaling 2929 interactions between species of the genus Phoradendron and their hosts. This data paper represents an updated compilation of a genus of parasitic plants, with the purpose of making this database of interactions accessible for researchers to address questions at multiple scales and from disciplines as varied as biogeography, ecology, evolution, and epidemiology. We plan to use and expand this database with subsequent studies from the authors. There are no copyright restrictions on the dataset; please cite this data paper when using data from this publication. We also encourage you to contact the authors if you are interested in contributing to this database.


Assuntos
Interações Hospedeiro-Parasita , Animais , Dispersão Vegetal
19.
J Hered ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248324

RESUMO

Polyergus kidnapper ants are widely distributed, but relatively uncommon, throughout the Holarctic, spanning an elevational range from sea level to over 3000 m. These species are well known for their obligate social parasitism with various Formica ant species, which they kidnap in dramatic, highly coordinated raids. Kidnapped Formica larvae and pupae become integrated into the Polyergus colony where they develop into adults and perform nearly all of the necessary colony tasks for the benefit of their captors. In California, Polyergus mexicanus is the most widely distributed Polyergus, but recent evidence has identified substantial genetic polymorphism within this species, including genetically divergent lineages associated with the use of different Formica host species. Given its unique behavior and genetic diversity, Polyergus mexicanus plays a critical role in maintaining ecosystem balance by influencing the population dynamics and genetic diversity of its host ant species, Formica, highlighting its conservation value and importance in the context of biodiversity preservation. Here, we present a high-quality genome assembly of P. mexicanus from a sample collected in Plumas County, CA, USA, in the foothills of the central Sierra Nevada. This genome assembly consists of 364 scaffolds spanning 252.31 Mb, with contig N50 of 481,250 kb, scaffold N50 of 10.36 Mb, and BUSCO completeness of 95.4%. We also assembled the genome of the Wolbachia endosymbiont of P. mexicanus - a single, circular contig spanning 1.23 Mb. These genome sequences provide essential resources for future studies of conservation genetics, population genetics, speciation, and behavioral ecology in this charismatic social insect.

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