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1.
Front Immunol ; 15: 1341464, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404575

RESUMO

Introduction: Guanylate-binding proteins (GBPs) are produced in response to pro-inflammatory signals, mainly interferons. The most studied cluster of GBPs in mice is on chromosome 3. It comprises the genes for GBP1-to-3, GBP5 and GBP7. In humans, all GBPs are present in a single cluster on chromosome 1. Brucella abortus is a Gram-negative bacterium known to cause brucellosis, a debilitating disease that affects both humans and animals. Our group demonstrated previously that GBPs present on murine chromosome 3 (GBPchr3) is important to disrupt Brucella-containing vacuole and GBP5 itself is important to Brucella intracellular LPS recognition. In this work, we investigated further the role of GBPs during B. abortus infection. Methods and results: We observed that all GBPs from murine chromosome 3 are significantly upregulated in response to B. abortus infection in mouse bone marrow-derived macrophages. Of note, GBP5 presents the highest expression level in all time points evaluated. However, only GBPchr3-/- cells presented increased bacterial burden compared to wild-type macrophages. Brucella DNA is an important Pathogen-Associated Molecular Pattern that could be available for inflammasome activation after BCV disruption mediated by GBPs. In this regard, we observed reduced IL-1ß production in the absence of GBP2 or GBP5, as well as in GBPchr3-/- murine macrophages. Similar result was showed by THP-1 macrophages with downregulation of GBP2 and GBP5 mediated by siRNA. Furthermore, significant reduction on caspase-1 p20 levels, LDH release and Gasdermin-D conversion into its mature form (p30 N-terminal subunit) was observed only in GBPchr3-/- macrophages. In an in vivo perspective, we found that GBPchr3-/- mice had increased B. abortus burden and higher number of granulomas per area of liver tissue, indicating increased disease severity. Discussion/conclusion: Altogether, these results demonstrate that although GBP5 presents a high expression pattern and is involved in inflammasome activation by bacterial DNA in macrophages, the cooperation of multiple GBPs from murine chromosome 3 is necessary for full control of Brucella abortus infection.


Assuntos
Brucelose , Proteínas de Ligação ao GTP , Animais , Camundongos , Brucella abortus/genética , Brucelose/microbiologia , Proteínas de Transporte/metabolismo , DNA Bacteriano , Inflamassomos/genética , Inflamassomos/metabolismo , Proteínas de Ligação ao GTP/genética
2.
Fundam Clin Pharmacol ; 38(1): 60-71, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37497790

RESUMO

BACKGROUND: The bacterium Staphylococcus aureus has stood out for presenting a high adaptability, acquiring resistance to multiple drugs. The search for natural or synthetic compounds with antibacterial properties capable of reversing the resistance of S. aureus is the main challenge to be overcome today. Natural products such as chalcones are substances present in the secondary metabolism of plants, presenting important biological activities such as antitumor, antidiabetic, and antimicrobial activity. OBJECTIVES: In this context, the aim of this work was to synthesize the chalcone (2E)-1-(3'-aminophenyl)-3-(4-dimethylaminophenyl)-prop-2-en-1-one with nomenclature CMADMA, confirm its structure by nuclear magnetic resonance (NMR), and evaluate its antibacterial properties. METHODS: The synthesis methodology used was that of Claisen-Schmidt, and spectroscopic characterization was performed by NMR. For microbiological assays, the broth microdilution methodology was adopted in order to analyze the antibacterial potential of chalcones and to analyze their ability to act as a possible inhibitor of ß-lactamase and efflux pump resistance mechanisms, present in S. aureus strain K4100. RESULTS: The results obtained show that CMADMA does not show direct antibacterial activity, expressing a MIC of ≥1024 µg/mL, or on the enzymatic mechanism of ß-lactamase; however, when associated with ethidium bromide in efflux pump inhibition assays, CMADMA showed promising activity by reducing the MIC of the bromide from 64 to 32 µg/mL. CONCLUSION: We conclude that the chalcone synthesized in this study is a promising substance to combat bacterial resistance, possibly acting in the inhibition of the QacC efflux pump present in S. aureus strain K4100, as evidenced by the reduction in the MIC of ethidium bromide.


Assuntos
Chalcona , Chalconas , Staphylococcus aureus , Chalcona/farmacologia , Chalcona/metabolismo , Chalconas/farmacologia , Etídio/metabolismo , Etídio/farmacologia , beta-Lactamases/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
3.
Pathogens ; 12(12)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38133271

RESUMO

The bacillus Calmette-Guérin (BCG) is an attenuated bacterium derived from virulent Mycobacterium bovis. It is the only licensed vaccine used for preventing severe forms of tuberculosis in children. Besides its specific effects against tuberculosis, BCG administration is also associated with beneficial non-specific effects (NSEs) following heterologous stimuli in humans and mice. The NSEs from BCG could be related to both adaptive and innate immune responses. The latter is also known as trained immunity (TI), a recently described biological feature of innate cells that enables functional improvement based on metabolic and epigenetic reprogramming. Currently, the mechanisms related to BCG-mediated TI are the focus of intense research, but many gaps are still in need of elucidation. This review discusses the present understanding of TI induced by BCG, exploring signaling pathways that are crucial to a trained phenotype in hematopoietic stem cells and monocytes/macrophages lineage. It focuses on BCG-mediated TI mechanisms, including the metabolic-epigenetic axis and the inflammasome pathway in these cells against intracellular pathogens. Moreover, this study explores the TI in different immune cell types, its ability to protect against various intracellular infections, and the integration of trained innate memory with adaptive memory to shape next-generation vaccines.

4.
J Immunol ; 211(5): 791-803, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37477668

RESUMO

The bacillus Calmette-Guérin (BCG) can elicit enhanced innate immune responses against a wide range of infections, known as trained immunity. Brucella abortus is the causative agent of brucellosis, a debilitating disease that affects humans and animals. In this study, we demonstrate that C57BL/6 mouse bone marrow-derived macrophages under BCG training enhance inflammatory responses against B. abortus. BCG-trained macrophages showed increased MHC class II and CD40 expression on the cell surface and higher IL-6, IL-12, and IL-1ß production. The increase in IL-1ß secretion was accompanied by enhanced activation of canonical and noncanonical inflammasome platforms. We observed elevated caspase-11 expression and caspase-1 processing in BCG-trained macrophages in response to B. abortus compared with untrained cells. In addition, these BCG-trained cells showed higher NLRP3 expression after B. abortus infection. From a metabolic point of view, signaling through the Akt/mammalian target of rapamycin/S6 kinase pathway was also enhanced. In addition, BCG training resulted in higher inducible NO synthase expression and nitrite production, culminating in an improved macrophage-killing capacity against intracellular B. abortus. In vivo, we monitored a significant reduction in the bacterial burden in organs from BCG-trained C57BL/6 mice when compared with the untrained group. In addition, previous BCG immunization of RAG-1-deficient mice partially protects against Brucella infection, suggesting the important role of the innate immune compartment in this scenario. Furthermore, naive recipient mice that received BM transfer from BCG-trained donors showed greater resistance to B. abortus when compared with their untrained counterparts. These results demonstrate that BCG-induced trained immunity in mice results in better control of intracellular B. abortus in vivo and in vitro.


Assuntos
Brucella abortus , Brucelose , Humanos , Animais , Camundongos , Vacina BCG , Camundongos Endogâmicos C57BL , Macrófagos , Brucelose/metabolismo , Caspases/metabolismo , Mamíferos
5.
Plants (Basel) ; 12(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37111810

RESUMO

Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus are the primary bacteria that cause clinical infections, such as urinary and intestinal infections, pneumonia, endocarditis, and sepsis. Bacterial resistance is an innate natural occurrence in microorganisms, resulting from mutations or the lateral exchange of genetic material. This serves as evidence for the association between drug consumption and pathogen resistance. Evidence has demonstrated that the association between conventional antibiotics and natural products is a promising pharmacological strategy to overcome resistance mechanisms. Considering the large body of research demonstrating the significant antimicrobial activities of Schinus terebinthifolius Raddi, the present study aimed to evaluate the chemical composition and antibiotic-enhancing effects of Schinus terebinthifolius Raddi essential oil (STEO) against the standard and multidrug-resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The STEO was extracted by hydrodistillation using a Clevenger-type vacuum rotary evaporator. The Minimum Inhibitory Concentration (MIC) of the STEO was assessed by the microdilution method to evaluate the antibacterial activity. The antibiotic-enhancing activity of the essential oil was assessed by determining the MIC of antibiotics in the presence of a sub-inhibitory concentration (MIC/8) of the natural product. The GC-MS analysis revealed alpha-pinene (24.3%), gamma-muurolene (16.6%), and myrcene (13.7%) as major constituents of the STEO. The STEO potentiated the enhanced antibacterial activity of norfloxacin and gentamicin against all the strains and increased the action of penicillin against the Gram-negative strains. Therefore, it is concluded that although the STEO does not exhibit clinically effective antibacterial activity, its association with conventional antibiotics results in enhanced antibiotic activity.

6.
Arq. ciências saúde UNIPAR ; 27(10): 5588-5602, 2023.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1511778

RESUMO

Com grande impacto social por alta mortalidade e morbidade no Brasil e no Mundo, o AVC continua em destaque dentre as Doenças Crônicas Não transmissíveis. Visando oferecer subsídios técnico-científicos sobre o perfil epidemiológico desta patologia no Nordeste, este artigo consiste em um estudo de corte transversal, quantitativo, epidemiológico, de série temporal, entre os anos de 2015 a 2019, tendo por base os dados disponibilizados na plataforma DATASUS. Evidenciou-se que o ano de 2019 foi o ano com maior número de internações por esta patologia, predominando em homens. No entanto, as mulheres tiveram mais óbitos. A raça mais acometida foi a parda, com mais de 82% das internações e mais de 83% dos óbitos. Os óbitos ocorreram em todas as faixas etárias, predominando nos mais idosos. O Estado com maior quantitativo de óbitos foi a Bahia, também o mais populoso do estudo. O perfil epidemiológico geral, do paciente acometido por AVC na região Nordeste do Brasil no período avaliado, foi, homem, com idade mais avançada (a partir de 60 anos), pardo, permanecendo cerca de 7,8 dias internados. O custo total desse período, com internações por AVC, foi de R$278.874.426.3, certamente, um custo bastante oneroso ao nosso sistema de saúde. As unidades federativas com maior acometimento são também as mais populosas. Percebendo-se que, por se tratar de uma doença prevenível, com graves sequelas e que causam grandes prejuízos pessoais, sociais e econômicos, torna-se relevante que o sistema público de saúde adote rigorosas medidas para sua prevenção.


With a great social impact due to high mortality and morbidity in Brazil and the world, stroke continues to be highlighted among Chronic Non-communicable Diseases. Aiming to offer technical-scientific support on the epidemiological profile of this pathology in the Northeast, this article consists of a cross-sectional, quantitative, epidemiological, time series study, between the years 2015 and 2019, based on data available on the DATASUS platform . It was evident that 2019 was the year with the highest number of hospitalizations for this pathology, predominantly in men. However, women had more deaths. The most affected race was the mixed race, with more than 82% of hospitalizations and more than 83% of deaths. Deaths occurred in all age groups, predominantly among the elderly. The State with the highest number of deaths was Bahia, also the most populous in the study. The general epidemiological profile of the patient affected by stroke in the Northeast region of Brazil during the period evaluated was male, older (60 years and older), mixed race, and remained hospitalized for approximately 7.8 days. The total cost of this period, with hospitalizations for stroke, was R$278,874,426.3, certainly a very costly cost to our health system. The federative units most affected are also the most populous. Realizing that, as it is a preventable disease, with serious consequences and causing great personal, social and economic losses, it is important that the public health system adopts strict measures for its prevention.


Con gran impacto social debido a la alta mortalidad y morbilidad en Brasil y el mundo, el accidente cerebrovascular sigue destacándose entre las Enfermedades Crónicas No Transmisibles. Con el objetivo de ofrecer soporte técnico-científico sobre el perfil epidemiológico de esta patología en el Nordeste, este artículo consiste en un estudio transversal, cuantitativo, epidemiológico, de series temporales, entre los años 2015 y 2019, con base en datos disponibles en la plataforma DATASUS. . Se evidenció que 2019 fue el año con mayor número de hospitalizaciones por esta patología, predominantemente en hombres. Sin embargo, las mujeres tuvieron más muertes. La raza más afectada fue la mestiza, con más del 82% de las hospitalizaciones y más del 83% de las muertes. Las muertes se produjeron en todos los grupos de edad, predominantemente entre los ancianos. El estado con mayor número de muertes fue Bahía, también el más poblado del estudio. El perfil epidemiológico general del paciente afectado por accidente cerebrovascular en la región Nordeste de Brasil durante el período evaluado fue masculino, mayor (60 años y más), mestizo y permaneció hospitalizado durante aproximadamente 7,8 días. El costo total de este período, con las hospitalizaciones por accidente cerebrovascular, fue de R$ 278.874.426,3, ciertamente un costo muy costoso para nuestro sistema de salud. Las unidades federativas más afectadas son también las más pobladas. Al ser conscientes de que, al tratarse de una enfermedad prevenible, de graves consecuencias y que provoca grandes pérdidas personales, sociales y económicas, es importante que el sistema público de salud adopte medidas estrictas para su prevención. PALABRAS CLAVE: Accidente Cerebrovascular; Epidemiología; Salud Pública.

7.
J Infect Public Health ; 15(3): 373-377, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34656506

RESUMO

In a recent study, our research group demonstrated that the essential oil of Ocotea odorifera (EOOO) and its major compound safrole potentiated the action fluoroquinolones, modulating bacterial resistance possibly due to direct inhibition of efflux pumps. Thus, in the present study, we investigated whether these treatments could enhance the activity of gentamicin and erythromycin against multidrug-resistant (MDR) bacteria. The EOOO was extracted by hydrodistillation, and the phytochemical analysis was performed by gas chromatography coupled to mass spectrometry (GC-MS). The antibiotic-enhancing effect of the EOOO and safrole against MDR strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa was analyzed by the broth microdilution method. The chemical analysis confirmed the presence of safrole as a major component among the 16 compounds identified in the EOOO. Both the essential oil and the isolated compound showed clinically relevant antibacterial activities against S. aureus. Regarding the modulation of antibiotic resistance, the EOOO was found to enhance the activity of erythromycin against the strains of P. aeruginosa and S. aureus, as well as improving the action of gentamicin against S. aureus. On the other hand, safrole potentiated the activity of gentamicin against the S. aureus strain alone. It is concluded, therefore, that the EOOO and safrole can enhance the activity of macrolides and aminoglycosides, and as such are useful in the development of therapeutic tools to combat bacterial resistance against these classes of antibiotics.


Assuntos
Ocotea , Óleos Voláteis , Antibacterianos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Safrol/farmacologia , Staphylococcus aureus
8.
Mult Scler Relat Disord ; 56: 103260, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34562767

RESUMO

BACKGROUND: Biomarkers have improved the classification of autoimmune inflammatory disorders, including optic neuritis (ON) as a frequent presentation of multiple sclerosis, neuromyelitis spectrum disorders, MOG antibody-related disease (MOGAD), and opticospinal multiple sclerosis (OSMS). The phenotype of OSMS in non-Asian populations is less well known. OBJECTIVE: We investigated the clinical features and prognosis of OSMS-ON in a Brazilian cohort. METHODS: This was a single-center cohort study of patients from Rio de Janeiro (Brazil) with OSMS. All individuals were MOG- and AQP4-seronegative, clinically diagnosed with ON, and had magnetic resonance imaging-confirmed transverse myelitis (TM). Subjects and healthy controls (HCs) were assessed for visual acuity (logMAR VA), automated perimetry mean deviation (MD), intraocular pressure, and spectral-domain optical coherence tomography (OCT), followed by automated retinal layer segmentation of the peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell and inner plexiform layer (mGCIPL). Receiver operator characteristic curves were plotted and the area under the curve (AUC) was calculated for group comparisons of retinal asymmetry of the pRNFL and mGCIPL. RESULTS: The 30 patients with OSMS were predominantly female and white. The mean age was 48 years (range 20-70 years). Unilateral ON was the index event in 83.3% of patients. Over the average 18-year follow-up period, there were 89 relapses of ON. In individuals with OSMS, the average VA was 0.07±0.14 in the right eye (RE) and 0.13±0.30 in the left eye (LE). The MD was -5.37±5.88 dB and -5.23±3.34 dB for the RE and LE, respectively. There was a significant cumulative loss of VA (p = 0.0003) and MD (p = 0.0001) with a higher number of recurrent episodes. Atrophy of the pRNFL thickness was significant in OSMS (RE, 78.62 ± 16.01 µm; LE, 79.86 ± 13.79 µm) relative to the HC group (RE, 98.87 ± 10.68 µm; LE, 97.87 ± 10.85 µm, p = 0.0001). Likewise, there was significant mGCIPL atrophy in patients with OSMS (RE, 74.96 ± 14.46 µm; LE, 73.88 ± 13.79 µm) relative to the HC group (RE, 90.50 ± 6.74 µm; LE, 90.41± 6.89 µm; p = 0.0001). Retinal asymmetry, inter-eye percentage, and absolute differences accurately separated patients with unilateral ON from HCs (AUC=0.89 and AUC=0.85, respectively). CONCLUSION: A structural-functional paradox was found in OSMS with a high diagnostic value for a novel metric based on retinal asymmetry. The functional visual outcome are excellent despite significant structural damage to the inner retinal layers in patients with a high ON relapse rate and long-term bilateral sequential involvement.


Assuntos
Esclerose Múltipla , Neurite Óptica , Adulto , Idoso , Brasil , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico por imagem , Recidiva Local de Neoplasia , Oncostatina M , Neurite Óptica/complicações , Neurite Óptica/diagnóstico por imagem , Adulto Jovem
9.
Sci Rep ; 11(1): 15648, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34341449

RESUMO

Bacillus Calmette-Guerin (BCG) is the only FDA approved first line therapy for patients with nonmuscle invasive bladder cancer. The purpose of this study is to better understand the role of innate immune pathways involved in BCG immunotherapy against murine bladder tumor. We first characterized the immunological profile induced by the MB49 mouse urothelial carcinoma cell line. MB49 cells were not able to activate an inflammatory response (TNF-α, IL-6, CXCL-10 or IFN-ß) after the stimulus with different agonists or BCG infection, unlike macrophages. Although MB49 cells are not able to induce an efficient immune response, BCG treatment could activate other cells in the tumor microenvironment (TME). We evaluated BCG intratumoral treatment in animals deficient for different innate immune molecules (STING-/-, cGAS-/-, TLR2-/-, TLR3-/-, TLR4-/-, TLR7-/-, TLR9-/-, TLR3/7/9-/-, MyD88-/-, IL-1R-/-, Caspase1/11-/-, Gasdermin-D-/- and IFNAR-/-) using the MB49 subcutaneous mouse model. Only MyD88-/- partially responded to BCG treatment compared to wild type (WT) mice, suggesting a role played by this adaptor molecule. Additionally, BCG intratumoral treatment regulates cellular infiltrate in TME with an increase of inflammatory macrophages, neutrophils and CD8+ T lymphocytes, suggesting an immune response activation that favors tumor remission in WT mice but not in MyD88-/-. The experiments using MB49 cells infected with BCG and co-cultured with macrophages also demonstrated that MyD88 is essential for an efficient immune response. Our data suggests that BCG immunotherapy depends partially on the MyD88-related innate immune pathway.


Assuntos
Imunoterapia , Microambiente Tumoral , Neoplasias da Bexiga Urinária , Animais , Carcinoma de Células de Transição , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos
10.
Integr Zool ; 16(1): 2-18, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32929877

RESUMO

Modern and paleoclimate changes may have altered species dynamics by shifting species' niche suitability over space and time. We analyze whether the current genetic structure and isolation of the two large American felids, jaguar (Panthera onca) and puma (Puma concolor), are mediated by changes in climatic suitability and connection routes over modern and paleoclimatic landscapes. We estimate species distribution under 5 climatic landscapes (modern, Holocene, last maximum glaciations [LMG], average suitability, and climatic instability) and correlate them with individuals' genetic isolation through causal modeling on a resemblance matrix. Both species exhibit genetic isolation patterns correlated with LMG climatic suitability, suggesting that these areas may have worked as "allele refuges." However, the jaguar showed higher vulnerability to climate changes, responding to modern climatic suitability and connection routes, whereas the puma showed a continuous and gradual transition of genetic variation. Despite differential responsiveness to climate change, both species are subjected to the climatic effects on genetic configuration, which may make them susceptible to future climatic changes, since these are progressing faster and with higher intensity than changes in the paleoclimate. Thus, the effects of climatic changes should be considered in the design of conservation strategies to ensure evolutionary and demographic processes mediated by gene flow for both species.


Assuntos
Mudança Climática , Panthera/genética , Puma/genética , Distribuição Animal , Animais , Ecossistema , Variação Genética , Repetições de Microssatélites , Modelos Estatísticos
11.
Z Naturforsch C J Biosci ; 76(1-2): 35-42, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32673283

RESUMO

The objective of this study was to determine the chemical profile and to evaluate the antibacterial activity of the essential oils of Piper species and modulation of the antibiotic activity, using the microdilution method to determine the minimum inhibitory concentration. The chemical components were characterized by gas chromatography coupled to mass spectrometry, which revealed ß-copaen-4-α-ol (31.38%), spathulenol (25.92%), and germacrene B (21.53%) as major constituents of the essential oils of Piper arboreum, Piper aduncum, and Piper gaudichaudianum, respectively. The essential oils analyzed in this study did not present a clinically relevant activity against standard and multiresistant Escherichia coli. However, in the case of multiresistant Staphylococcus aureus, there was a significant activity, corroborating with reports in the literature, where Gram-positive bacteria are more susceptible to antimicrobial activity. The essential oils modulated the effect of the antibiotics norfloxacin and gentamicin, having on the latter greater modulating effect; however, for erythromycin, no statistically significant effect was observed. In conclusion, the results obtained in this study demonstrated that the essential oils of the analyzed Piper species present an inhibitory effect against S. aureus and modulate antibiotic activity, most of which presents synergistic activity.


Assuntos
Antibacterianos/química , Óleos Voláteis/química , Piper/química , Óleos de Plantas/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Sesquiterpenos/análise , Sesquiterpenos de Germacrano/análise , Staphylococcus aureus/efeitos dos fármacos
12.
Rev. bras. parasitol. vet ; 30(3): e002921, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1251395

RESUMO

Abstract The present study reports on patterns of parasitism by Amblyomma humerale on yellow-footed tortoise, Chelonoidis denticulatus, in the Atlantic Forest of southeastern Brazil. The tortoises were sampled occasionally, from July 2005 to January 2020. We collected 81 adult ticks from seven tortoises (mean = 11.57 ± 6.90 ticks/host), of which 72 were males (88.9%) and nine females (11.1%), resulting in an 8:1 sex ratio (males:females). Males were found in clusters, attached to the carapace. Females occurred mainly isolated, attached to coriaceous integumental areas (n = 7; 77.8%), especially the engorged females (100%). We suggest that the difference between attachment sites is a strategy used by fertilized females to avoid mechanical removal from their host through friction with elements of the environment. Because they undergo a considerable increase of volume when engorged, they move to more sheltered places on their host's surface. The parasitism patterns by A. humerale on C. denticulatus were compatible with those observed in the Amazon region and in the Cerrado-Amazonia transition. The present work provides information about the life history and host-parasite interface of the two species and contributes to understanding the parasitism patterns by A. humerale on C. denticulatus in the Atlantic Forest of southeastern Brazil.


Resumo O presente estudo relata os padrões de parasitismo de Amblyomma humerale em jabuti-tinga, Chelonoidis denticulatus, na Mata Atlântica do Sudeste do Brasil. Os jabutis foram amostrados de forma ocasional, entre julho de 2005 e janeiro de 2020. Foram amostrados sete jabutis e coletados 81 carrapatos adultos (media = 11,57 ± 6,90 carrapatos/hospedeiro), sendo 72 machos (88,9%) e nove fêmeas (11,1%), resultando em uma razão sexual de 8:1 (machos:fêmeas). Os machos encontravam-se agrupados e aderidos à carapaça. As fêmeas ocorreram principalmente isoladas e fixadas a áreas de tegumento coriáceo (n = 7; 77,8%), especialmente as fêmeas ingurgitadas (100%). Sugere-se que a diferença entre os locais de fixação seja uma estratégia das fêmeas fecundadas, para evitar a remoção mecânica por atrito com o ambiente, uma vez que aumentam consideravelmente seu volume quando ingurgitadas, deslocando-se para locais mais abrigados na superfície do hospedeiro. Os padrões de parasitismo de C. denticulatus por A. humerale foram compatíveis com aqueles observados na Amazônia e na transição Amazônia-Cerrado. O presente trabalho contribui com informações acerca da história de vida e da relação parasito-hospedeiro entre as duas espécies, contribuindo para o entendimento dos padrões de parasitismo de A. humerale em C. denticulatus na Mata Atlântica do sudeste do Brasil.


Assuntos
Animais , Masculino , Feminino , Tartarugas , Ixodidae , Brasil , Florestas , Amblyomma
13.
J Leukoc Biol ; 108(4): 1279-1291, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32620042

RESUMO

Guanylate binding proteins (GBPs) are important effector molecules of autonomous response induced by proinflammatory stimuli, mainly IFNs. The murine GBPs clustered in chromosome 3 (GBPchr3) contains the majority of human homologous GBPs. Despite intense efforts, mycobacterial-promoted diseases are still a major public health problem. However, the combined importance of GBPchr3 during mycobacterial infection has been overlooked. This study addresses the influence of the GBPchr3 in host immunity against mycobacterial infection to elucidate the relationship between cell-intrinsic immunity and triggering of an efficient anti-mycobacterial immune response. Here we show that all GBPchr3 are up-regulated in lungs of mice during Mycobacterium bovis BCG infection, resembling tissue expression of IFN-γ. Mice deficient in GBPchr3 (GBPchr3-/- ) were more susceptible to infection, displaying diminished expression of autophagy-related genes (LC3B, ULK1, and ATG5) in lungs. Additionally, there was reduced proinflammatory cytokine production complementary to diminished numbers of myeloid cells in spleens of GBPchr3-/- . Higher bacterial burden in GBPchr3-/- animals correlated with increased number of tissue granulomas. Furthermore, absence of GBPchr3 hampered activation and production of TNF-α and IL-12 by dendritic cells. Concerning macrophages, lack of GBPs impaired their antimicrobial function, diminishing autophagy induction and intracellular killing efficiency. In contrast, single GBP2 deficiency did not contribute to in vivo bacterial control. In conclusion, this study shows that GBPchr3 are important not only to stimulate cell-intrinsic immunity but also for inducing an efficient immune response to control mycobacterial infection in vivo.


Assuntos
Cromossomos de Mamíferos/imunologia , Proteínas de Ligação ao GTP/imunologia , Mycobacterium bovis/imunologia , Tuberculose/imunologia , Animais , Cromossomos de Mamíferos/genética , Células Dendríticas/imunologia , Células Dendríticas/patologia , Proteínas de Ligação ao GTP/genética , Interleucina-12/genética , Interleucina-12/imunologia , Macrófagos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , Tuberculose/genética , Tuberculose/patologia , Tuberculose/veterinária , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
14.
Microb Pathog ; 145: 104223, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32376358

RESUMO

Essential oils are secondary metabolites with immense pharmacological potential.These substances are abundantly produced by plants of the family Asteraceae, such as Baccharis coridifolia. Previous studies have demonstrated that this species has pharmacological properties that make it a promising source of new antibacterial agents. Therefore, the present study aimed to evaluate the antibacterial and antibiotic-modulating activity of Baccharis coridifolia essential oil against multidrug-resistant (MDR) strains. The phytochemical analysis was carried out by gas chromatography coupled to Mass Spectroscopy (GC/MS), and realized the Minimum Inhibitory Concentation (MIC) and antibiotic-modulation from the microdilution method in 96-well plates. It was revealed the presence of germacrene D (23.7%), bicyclogermacrene (17.1%), and (E)-caryophyllene (8.4%) as major components. The minimum inhibitory concentration of essential oil against strains of Pseudomonas aeruginosa (512 µg/mL) and Staphylococcus aureus (128 µg/mL) demonstrated clinically relevant antibacterial activity. In addition, the combination of subinhibitory doses of the oil with conventional antibiotics showed synergism, indicating potentiation of the antibacterial effect. In conclusion, the essential oil of Baccharis coridifolia (EOBc) presented antibacterial and antibiotic-modulating activities that place this species as a source of molecules useful in the fight against bacterial resistance.


Assuntos
Baccharis , Óleos Voláteis , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Folhas de Planta
15.
Antibiotics (Basel) ; 9(5)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408576

RESUMO

Considering the evidence that essential oils, as well as safrole, could modulate bacterial growth in different resistant strains, this study aims to characterize the phytochemical profile and evaluate the antibacterial and antibiotic-modulating properties of the essential oil Ocotea odorífera (EOOO) and safrole against efflux pump (EP)-carrying strains. The EOOO was extracted by hydrodistillation, and the phytochemical analysis was performed by gas chromatography coupled to mass spectrometry (GC-MS). The antibacterial and antibiotic-modulating activities of the EOOO and safrole against resistant strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were analyzed through the broth microdilution method. The EP-inhibiting potential of safrole in association with ethidium bromide or antibiotics was evaluated using the S. aureus 1199B and K2068 strains, which carry genes encoding efflux proteins associated with antibiotic resistance to norfloxacin and ciprofloxacin, respectively. A reduction in the MIC of ethidium bromide or antibiotics was used as a parameter of EP inhibition. The phytochemical analysis identified 16 different compounds in the EOOO including safrole as the principal constituent. While the EOOO and safrole exerted clinically relevant antibacterial effects against S. aureus only, they potentiated the antibacterial activity of norfloxacin against all strains evaluated by our study. The ethidium bromide and antibiotic assays using the strains of S. aureus SA1119B and K2068, as well as molecular docking analysis, indicated that safrole inhibits the NorA and MepA efflux pumps in S. aureus. In conclusion, Ocotea odorifera and safrole presented promising antibacterial and antibiotic-enhancing properties, which should be explored in the development of drugs to combat antibacterial resistance, especially in strains bearing genes encoding efflux proteins.

16.
Food Chem Toxicol ; 136: 111023, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31866146

RESUMO

The present study evaluated the effect of the essential oil of Mikania cordifolia (EOMc) and its major constituent limonene alone or associated with antibacterial drugs against Multidrug Resistant Bacteria (MDR). To evaluate the antibacterial activity, the minimum inhibitory concentrations (MIC) of the oil and limonene against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus were determined. The antibiotic-modulating activity was assessed using subinhibitory concentrations (MIC/8) of these substances in combination with conventional antibacterial drugs. Although no relevant antibacterial activity of the natural products was detected, both substances modulated the action of antibiotics against resistant bacteria. The EOMc demonstrated the best modulating effect against P. aeruginosa, presenting synergistic effects when associated with gentamicin and norfloxacin. In addition, the oil reduced the MIC of norfloxacin against E. coli as well as reduced the MIC of gentamicin against S. aureus. On the other hand, the best effect of limonene was obtained against S. aureus. Thus, it is concluded that the essential oil Mikania cordifolia and the isolated compound limonene do not have clinically significant antibacterial effect, but modulate the action of antibiotics against MDR bacteria.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Limoneno/farmacologia , Mikania/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Gentamicinas/farmacologia , Testes de Sensibilidade Microbiana , Norfloxacino/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
17.
Biota Neotrop. (Online, Ed. ingl.) ; 20(4): e20190943, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1131948

RESUMO

Abstract: Anurans are predator and prey, playing an important role in ecosystem functioning. The diet composition is closely related to feeding strategy, and the information about prey items is useful to understand intra and interspecific interactions in trophic webs. Here we determined diet composition, feeding strategy, and relation between prey ingestion and body measures of Crossodactylus timbuhy, a recently described anuran species. We found 466 prey items from 20 prey categories in the stomach of 66 specimens (15 males and 51 females) of C. timbuhy. The diet consists mostly of Formicidae and Coleoptera, the items with the highest number, frequency of occurrence and prey importance. The diet composition was relatively similar to other species of Crossodactylus. Prey volume was positively related to frog size and weight, suggesting frogs may feed upon any prey they can swallow. Diet showed some variation between sexes. Despite females were larger and heavier than males, females had higher consumption of smaller prey, and ingested a larger number of prey categories. We suggest C. timbuhy has an invertebrate-opportunistic feeding habit. It is likely C. timbuhy uses a combination of 'sit-and-wait' and 'active search' strategies due to high consumption of both highly mobile and sedentary prey.


Resumo: Os anuros são predadores e presas, desempenhando um importante papel no funcionamento dos ecossistemas. A composição da dieta está intimamente relacionada à estratégia de forrageamento das espécies e as informações sobre os itens consumidos são úteis para compreensão das interações intra e interespecíficas nas redes tróficas. O presente estudo objetivou determinar a composição da dieta, a estratégia de forrageamento e a relação entre a ingestão de presas e as medidas corporais de Crossodactylus timbuhy, uma espécie de anuro descrita recentemente. Foi analisado o conteúdo estomacal de 66 espécimes (15 machos e 51 fêmeas) de C. timbuhy e registrados 466 itens alimentares, distribuídos em 20 categorias de presas. A dieta consistiu principalmente de Formicidae e Coleoptera, as quais apresentaram maior número de itens consumidos, maior frequência de ocorrência e maior importância entre as presas registradas. A composição da dieta foi relativamente semelhante à de outras espécies do gênero Crossodactylus. O volume das presas foi positivamente relacionado com o tamanho e o peso dos espécimes, sugerindo que os indivíduos podem se alimentar de qualquer presa que eles possam engolir. A dieta apresentou variação entre os sexos. Apesar das fêmeas serem maiores e mais pesadas do que os machos, elas consumiram mais presas menores e ingeriram mais categorias de presas. Sugere-se que C. timbuhy tenha hábito alimentar invertebrado-oportunista. É provável que C. timbuhy apresente uma combinação de estratégias "senta-e-espera" e "forrageador ativo" devido ao alto consumo de presas altamente móveis e de presas sedentárias.

18.
Acta Med Port ; 32(7-8): 499-504, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31445529

RESUMO

INTRODUCTION: Children's exposure to secondhand smoke is a cause of serious health problems and infant morbidity. This is the first nationally representative study conducted in Portugal to describe the prevalence of children exposed to secondhand smoke at home and in the car. MATERIAL AND METHODS: This is a descriptive cross-sectional study with a representative sample of 2396 Portuguese children aged 0 to 9 years old, stratified by age and administrative region NUTS II. Questionnaires were administered between January and September 2016. RESULTS: Results showed that 6.1% of mothers and 11.2% of fathers reported smoking at home. It was found that 4.5% of mothers and 8.3% of fathers reported smoking in the car. Results also showed that 5.4% of children were double exposed to secondhand smoke at home and in the car. Children whose parents were smokers and had a lower level of education were more exposed to secondhand smoke at home. DISCUSSION: Children's exposure to secondhand smoke has been decreasing in Portugal. Parental smoking and a low educational level were risk factors for children's exposure to secondhand smoke at home. CONCLUSION: The main source of children's exposure to secondhand smoke is parental smoking. As such, it is crucial to implement effective measures to control parental smoking. It is necessary to promote smoking cessation among parents and to ban smoking inside the car.


Introdução: A exposição das crianças ao fumo ambiental do tabaco é uma importante causa de graves problemas de saúde e morbilidade infantil. Este é o primeiro estudo com representatividade nacional realizado em Portugal a descrever a prevalência de crianças expostas ao fumo ambiental do tabaco em casa e no carro. Material e Métodos: Trata-se de um estudo transversal descritivo que inclui uma amostra representativa de 2396 crianças portuguesas dos 0 aos 9 anos de idade, estratificada por idade e por região administrativa NUTS II. A aplicação de questionários decorreu entre janeiro e setembro de 2016. Resultados: Verifica-se que 6,1% das mães e 11,2% dos pais fumam no domicílio. Constata-se que 4,5% das mães e 8,3% dos pais fumam no carro. Verifica-se também que 5,4% das crianças estão duplamente expostas ao fumo ambiental do tabaco em casa e no carro. As crianças cujos pais são fumadores e com menor nível de escolaridade, estão mais expostas ao fumo ambiental do tabaco em casa. Discussão: A exposição das crianças ao fumo ambiental do tabaco tem diminuído em Portugal. Ainda assim, o consumo de tabaco dos pais e um baixo nível de escolaridade são fatores de risco para a exposição das crianças em casa. Conclusão: Uma vez que a principal fonte de exposição das crianças ao fumo ambiental do tabaco é o tabagismo dos pais, é necessário promover a cessação tabágica junto dos mesmos, assim como implementar a proibição de fumar no carro.


Assuntos
Automóveis/estatística & dados numéricos , Habitação/estatística & dados numéricos , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Criança , Pré-Escolar , Estudos Transversais , Escolaridade , Exposição Ambiental/estatística & dados numéricos , Pai/educação , Pai/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Mães/educação , Mães/estatística & dados numéricos , Portugal/epidemiologia , Prevalência , Fumar/epidemiologia , Abandono do Hábito de Fumar , Inquéritos e Questionários
19.
Braz J Microbiol ; 50(3): 705-713, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31297747

RESUMO

Serpentine soils present unique characteristics such as a low Ca/Mg ratio, low concentration of nutrients, and a high concentration of heavy metals, especially nickel. Soil bacterial isolates from an ultramafic complex located in the tropical savanna known as the Brazilian Cerrado were studied. Nickel-tolerant bacteria were obtained, and their ability to remove nickel from a culture medium was assessed. Bacterial isolates presented higher tolerance to nickel salts than previously reported for bacteria obtained from serpentine environments in other regions of the world. In addition, the quantification of nickel in cell pellets indicated that at least four isolates may adsorb soluble forms of nickel. It is expected that information gathered in this study will support future efforts to exploit serpentine soil bacteria for biotechnological processes involving nickel decontamination from environmental samples.


Assuntos
Bactérias/metabolismo , Níquel/metabolismo , Alcaloides de Triptamina e Secologanina/análise , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Brasil , Filogenia , Alcaloides de Triptamina e Secologanina/metabolismo , Solo/química
20.
J Neuroimmunol ; 330: 12-18, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30769212

RESUMO

Due to their function in assisting B cells, TFH cells may be involved in the production of pathogenic IgG in neuromyelitis optica spectrum disorder (NMOSD). In the present study, the proportion of IL-6+ and IL-17+ TFH cell subsets was higher in NMOSD patients than healthy individuals. The frequency of both TFH cell subsets were directly associated with disease activity. By contrast, NMOSD patients with a higher proportion of IL-10+ TFH cell subsets showed a lower neurological disabilities score. In summary, all findings suggest that expansion of peripheral IL-6+ and IL-17+ TFH cells may be involved in the severity of NMOSD.


Assuntos
Interleucina-17/sangue , Interleucina-6/sangue , Neuromielite Óptica/sangue , Neuromielite Óptica/diagnóstico , Índice de Gravidade de Doença , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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