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During host cell invasion, Shigella escapes to the cytosol and polymerizes actin for cell-to-cell spread. To restrict cell-to-cell spread, host cells employ cell-autonomous immune responses including antibacterial autophagy and septin cage entrapment. How septins interact with the autophagy process to target Shigella for destruction is poorly understood. Here, we employed a correlative light and cryo-soft X-ray tomography (cryo-SXT) pipeline to study Shigella septin cage entrapment in its near-native state. Quantitative cryo-SXT showed that Shigella fragments mitochondria and enabled visualization of X-ray-dense structures (â¼30â nm resolution) surrounding Shigella entrapped in septin cages. Using Airyscan confocal microscopy, we observed lysine 63 (K63)-linked ubiquitin chains decorating septin-cage-entrapped Shigella. Remarkably, septins and K63 chains are present in separate bacterial microdomains, indicating they are recruited separately during antibacterial autophagy. Cryo-SXT and live-cell imaging revealed an interaction between septins and LC3B-positive membranes during autophagy of Shigella. Together, these findings demonstrate how septin-caged Shigella are targeted for autophagy and provide fundamental insights into autophagy-cytoskeleton interactions.
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Septinas , Shigella , Septinas/metabolismo , Shigella/metabolismo , Citoesqueleto/metabolismo , Autofagia/fisiologia , Ubiquitinas/metabolismoRESUMO
Tissue effector cells of the monocyte lineage can differentiate into different cell types with specific cell function depending on their environment. The phenotype, developmental requirements, and functional mechanisms of immune protective macrophages that mediate the induction of transplantation tolerance remain elusive. Here, we demonstrate that costimulatory blockade favored accumulation of DC-SIGN-expressing macrophages that inhibited CD8(+) T cell immunity and promoted CD4(+)Foxp3(+) Treg cell expansion in numbers. Mechanistically, that simultaneous DC-SIGN engagement by fucosylated ligands and TLR4 signaling was required for production of immunoregulatory IL-10 associated with prolonged allograft survival. Deletion of DC-SIGN-expressing macrophages in vivo, interfering with their CSF1-dependent development, or preventing the DC-SIGN signaling pathway abrogated tolerance. Together, the results provide new insights into the tolerogenic effects of costimulatory blockade and identify DC-SIGN(+) suppressive macrophages as crucial mediators of immunological tolerance with the concomitant therapeutic implications in the clinic.
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Moléculas de Adesão Celular/metabolismo , Rejeição de Enxerto/prevenção & controle , Transplante de Coração , Lectinas Tipo C/metabolismo , Macrófagos/imunologia , Receptores de Superfície Celular/metabolismo , Linfócitos T Reguladores/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Moléculas de Adesão Celular/genética , Células Cultivadas , Fatores de Transcrição Forkhead/metabolismo , Rejeição de Enxerto/etiologia , Tolerância Imunológica , Interleucina-10/metabolismo , Lectinas Tipo C/genética , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Terapia de Alvo Molecular , Receptores de Superfície Celular/genética , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Tolerância ao Transplante , Regulação para CimaRESUMO
In this study, we evaluated the antimicrobial activity of bacteria isolated from the marine sponges Hymeniacidon perlevis and Halichondria panicea against seven Acinetobacter baumannii strains, the majority of which were clinically relevant carbapenem-resistant A. baumannii strains. We observed the inhibitory activity of 18 (out of 114) sponge-isolated bacterial strains against all A. baumanii strains using medium-throughput solid agar overlay assays. These inhibitory strains belonged to the genera Lactococcus, Pseudomonas, and Vagococcus. In addition, this antimicrobial activity was validated through a liquid co-cultivation challenge using an inhibitory strain of each genus and a green fluorescent protein-tagged A. baumanii strain. Fluorescence measurements indicated that the growth of A. baumanii was inhibited by the sponge isolates. In addition, the inability of A. baumanii to grow after spreading the co-cultures on solid medium allowed us to characterize the activity of the sponge isolates as bactericidal. In conclusion, this study demonstrates that marine sponges are a reservoir of bacteria that deserves to be tapped for antibiotic discovery against A. baumanii.
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Acinetobacter baumannii , Antibacterianos , Carbapenêmicos , Testes de Sensibilidade Microbiana , Poríferos , Animais , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Acinetobacter baumannii/isolamento & purificação , Poríferos/microbiologia , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , AntibioseRESUMO
Many pathogens are related to carcinogenesis. Chronic inflammation, as a result of persistent infection, leads to DNA damage, higher expression of oncogenes, decreased apoptosis and immunosuppression, which are some of the reasons for cancer induction. Among parasites, Schistosoma, Opistorchis and Clonorchis are recognised as infectious agents which contribute to cancer. A relationship between Anisakis and cancer was hypothesised because cellular responses to Anisakis products could result in inflammation and DNA damage. Previous research has shown a decrease in CD8+ γδ T-cells and an increase in αß and γδ T-cell apoptosis in colon cancer (CC) samples. Ninety-two CC patients and 60 healthy subjects were recruited. γδ and αß T-cells were analysed, and their apoptosis was evaluated. Anti-Anisakis antibodies were tested in sera from CC patients and controls. Anti-Anisakis IgG, IgM, IgA and IgE antibodies were significantly higher in CC patients. A significant increase in anti-Anisakis IgA levels was observed in patients with angiolymphatic invasion. The number of all γδ T-cells, as well as CD3+ CD4+ αß T-cells, was significantly lower in CC patients. The apoptosis of all T-cells was significantly increased in patients with CC. We observed a significantly higher percentage of anti-Anisakis IgE positive patients having a deficit of CD3+ γδ T-cells. Our results suggest a relationship between Anisakis and CC.
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Anisakis , Anticorpos Anti-Helmínticos , Neoplasias do Colo , Humanos , Masculino , Pessoa de Meia-Idade , Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/imunologia , Feminino , Neoplasias do Colo/imunologia , Neoplasias do Colo/parasitologia , Idoso , Animais , Anisakis/imunologia , Adulto , Apoptose , Idoso de 80 Anos ou mais , Subpopulações de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologiaRESUMO
With the advent of tissue culture, and eventually the in vitro growth and maintenance of individual cell types, it became possible to ask mechanistic questions about whole organism physiology that are impractical to address within a captive setting or within the whole organism. The earliest studies focused on understanding the wound-healing response while refining cell growth and maintenance protocols from various species. In addition to its extensive use in biomedical research, this approach has been co-opted by comparative physiologists interested in reductionist/mechanistic questions related to how cellular physiology can help explain whole organism function. Here, we provide a historical perspective on the emergence of primary cell culture with an emphasis on fibroblasts followed by an overview of applying this method to ask questions about the role of life-history evolution in shaping organismal physiology at the cellular level, as well as the effect of exogenous factors (i.e., temperature, and oxygen availability) on cellular function. Finally, we propose future uses for primary fibroblasts to address questions in conservation biology and comparative physiology.
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Fibroblastos , Fisiologia Comparada , Células Cultivadas , Proliferação de Células , Fibroblastos/metabolismo , CicatrizaçãoRESUMO
Integration of reactive oxygen species (ROS)-mediated signal transduction pathways via redox sensors and the thiol-dependent signalling network is of increasing interest in cell biology for their implications in plant growth and productivity. Redox regulation is an important point of control in protein structure, interactions, cellular location, and function, with thioredoxins (TRXs) and glutaredoxins (GRXs) being key players in the maintenance of cellular redox homeostasis. The crosstalk between second messengers, ROS, thiol redox signalling, and redox homeostasis-related genes controls almost every aspect of plant development and stress response. We review the emerging roles of TRXs and GRXs in redox-regulated processes interacting with other cell signalling systems such as organellar retrograde communication and gene expression, especially in plants during their development and under stressful environments. This approach will cast light on the specific role of these proteins as redox signalling components, and their importance in different developmental processes during abiotic stress.
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Glutarredoxinas , Tiorredoxinas , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Glutarredoxinas/genética , Glutarredoxinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Oxirredução , Transdução de Sinais/fisiologia , Compostos de Sulfidrila/metabolismo , Transcrição GênicaRESUMO
The Bruton's tyrosine kinase inhibitor ibrutinib and the B-cell lymphoma 2 anti-apoptotic protein inhibitor venetoclax provide high response rates in chronic lymphocytic leukemia (CLL). However, there is a growing number of patients that relapse after treatment or show refractory disease, thus new targets and agents are still needed. We have previously reported the chemokine receptor CCR7 as a relevant deregulated target in CLL and have developed CAP-100, a novel therapeutic anti-CCR7 antibody that is under evaluation for relapse/refractory CLL (NCT04704323). While CCR7 expression has been shown to be down-modulated in CLL patients treated with ibrutinib, whether venetoclax acts in a similar manner remains unaddressed. Here, we aimed to document the impact of venetoclax on CCR7 expression in CLL cells, as well as on the pre-clinical activity of CAP-100. To this end, we addressed CCR7 expression by flow cytometry and the antibody efficacy by means of in vitro chemotactic and antibody-dependent cell-mediated cytotoxicity (ADCC) assays. Our data indicate that venetoclax treatment did not significantly modify CCR7 expression pattern nor CAP-100 mechanisms of action. Together, these findings support CAP-100 as an adjuvant therapy to venetoclax that may introduce additional modes of action in CLL therapy.
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Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Receptores CCR7/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , RecidivaRESUMO
Inflammaging, a "hallmark of aging," refers to a chronic, progressive increase in the proinflammatory status of mammals as they age, and this phenotype has been associated with many age-related diseases, including cardiovascular disease, arthritis and cancer. Though, inflammaging research is common in humans, there is a lack of data for this process for the domestic dog. Here, serum concentrations of IL-6, IL-1ß and TNF-α in healthy dogs of different body sizes and ages were measured to determine whether inflammaging may play a mechanistic role in aging rates in dogs, similar to those found in humans. Using a four-way ANOVA, a significant decrease in IL-6 concentrations in young dogs with the rest of the age categories showing increased IL-6 concentrations was found, similar to humans. However, only young dogs have decreased IL-6 concentrations, with adult dogs having similar IL-6 concentrations to senior and geriatric dogs, implying differences in aging rates between humans and dogs. And, there was a marginally significant interaction between sex*spayed or neutered status and IL-1ß concentrations with intact females having the lowest IL-1ß concentrations compared with intact males, and spayed and neutered dogs. The presence of estrogen in intact females may, overall, decrease inflammatory pathways. This implies that age at spaying or neutering may be an important aspect to consider for inflammaging pathways in dogs. Furthermore, sterilized dogs often die of immune-related diseases, which could be linked to the increases in IL-1ß in sterilized dogs found in this study.
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Interleucina-6 , Fator de Necrose Tumoral alfa , Animais , Cães , Feminino , Humanos , Masculino , Envelhecimento , Citocinas , FenótipoRESUMO
Intermetallic compounds in the Al-Pt system were systematically studied via hard X-ray photoelectron spectroscopy, focusing on the positions of Pt 4f and Al 2s core levels and valence band features. On one hand, with increasing Al content, the Pt 4f core levels shift towards higher binding energies (BE), revealing the influence of the atomic interactions (chemical bonding) on the electronic state of Pt. On the other hand, the charge transfer from Al to Pt increases with increasing Al content in Al-Pt compounds. These two facts cannot be combined using the standard "chemical shift" approach. Computational analysis reveals that higher negative effective charges of Pt atoms are accompanied by reduced occupancy of Pt 5d orbitals, leading to the limited availability of these electrons for the screening of the 4f core hole and this in turn explains the experimentally observed shift of 4f core levels to higher BE.
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BACKGROUND: Health concerns about the potential impact of exposure to fluoride via drinking water (DW) on neuropsychological development include behavioral outcomes such as ADHD. OBJECTIVE: We aimed to examine the association between prenatal maternal urinary fluoride and symptoms associated with attention-deficit/hyperactivity disorder (ADHD) at the age of 8 and 11 years. METHOD: Data from 255 to 236 mother-child pairs from the "Infancia y Medio Ambiente" (INMA) birth cohort (Gipuzkoa; Spain) with maternal urinary F adjusted for creatinine (MUFcr) during pregnancy (first and third trimester) and child assessments of ADHD-like symptoms reported by Conners' Rating Scales-Revised at age of 8 and 11 years was available. Clinical approach was also used: cut off criteria (T > 66). Multiple linear regression models were fitted when outcomes were analyzed as continuous, and logistic regression models when the outcomes were analyzed with a categorical clinical approach. Covariates related to maternal characteristics, birth outcomes, childhood, quality of family context and biomarkers of neuro-toxicants were used. RESULTS: No association was found between MUFcr levels during pregnancy and cognitive problems-inattention, hyperactivity or ADHD index score of symptoms at 8 or 11 years. When results were analyzed from the perspective of a clinical approach, at the age of 11 years, there were significant inverse association between MUFcr and being categorized as a cognitive problems-inattention case. ORs were also indicative of a lower risk, although not significant, for ADHD index at age 11. Sensitivity analyses, taking into consideration quality of family context or the levels of other toxicants during pregnancy showed similar results. CONCLUSIONS: Higher levels of MUFcr in pregnant women were associated with a lower risk of cognitive problems-inattention at 11 years. These findings are inconsistent with those from previous studies and indicate the need for other population-based studies to confirm or overturn these results.
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Transtorno do Deficit de Atenção com Hiperatividade , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Gravidez , Criança , Transtorno do Deficit de Atenção com Hiperatividade/induzido quimicamente , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Fluoretos/toxicidade , Terceiro Trimestre da Gravidez , Vitaminas , Creatinina , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologiaRESUMO
AIMS: To assess the results of a nursing-led program to treatment of minor health issues from Catalan health institute primary care teams during 2019 and 2020. BACKGROUND: In 2009, the Catalan health institute implemented a nursing program to deal with minor health problems. This nursing-led program includes an algorithm for each of the minor health problems and arose as a strategy to reorganise the flow of demand for care in primary care. DESIGN: A cross-sectional design. METHODS: Multicentric cross-sectional study. 392 primary care teams from the Catalan health institute participated in the study. STROBE guideline was followed in reporting this study. Patients attending any of the participating centres requesting a same-day consultation for minor health issues were registered. RESULTS: A total of 21,215,278 consultations were recorded: 18,284,105 for adult and 2,931,173 for paediatric patients. Minor health issue resolved by the nurse was achieved in 50.9% of adult patients and 55.4% of paediatric patients. The highest rates of resolution in adults (>85%) were as follows: burns, emergency contraception and injuries. The highest resolution rates (>84%) were as follows: burns, breastfeeding difficulties and infant colic. 87.7% of prescriptions issued by nurses were accepted by the family physician. CONCLUSIONS: The nursing-led program to treat minor health issues has been shown to present acceptable resolution for nurses in a large primary care setting. Nurses have been carrying out prescription activities with very favourable results. RELEVANCE TO CLINICAL PRACTICE: This study demonstrates that care provided to patients by nurses for minor health issues requiring preferential resolution is effective. Our results are useful in that they confirm both the effectiveness of the nursing-led program for minor health issues and the pharmacological prescriptions produced during patient appointments. PATIENT OR PUBLIC CONTRIBUTION: Patient's data were obtained through a program records system after the minor health issues appointments.
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Enfermagem de Atenção Primária , Adulto , Lactente , Humanos , Criança , Estudos Transversais , Atenção Primária à Saúde/métodos , Encaminhamento e Consulta , AlgoritmosRESUMO
Heat waves and cold snaps are projected to rise in magnitude, duration, interval, and harshness in the coming years. The current literature examining thermal impacts on the physiology of organisms rarely uses chronic, variable thermal acclimations despite the fact that climate change predictions project a more variable environment. If we are to determine species' susceptibility to climate change, chronic and variable lab acclimations should be prioritized. Here, we acclimated the eurytolerant sheepshead minnow (Cyprinodon variegatus) to two extreme cycling thermal regimes: one warm [resting 27 °C with a spike to 33 °C for 8 h daily], one cold [resting 6.5 °C with a spike to 12 °C for 8 h daily], and three chronically stable conditions (10, 22, and 30 °C) for comparison. We measured enzymatic antioxidants (catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)), total antioxidant capacity, lipid peroxidation (LPO) damage, and citrate synthase (CS) activity in white epaxial muscle. Of particular note, we found significant increases in log CAT activity and SOD concentration in the warm cycling temperatures, and significant increases in GPx activity in the cold cycling temperatures. We found no significant accumulation of LPO damage in any of our thermal acclimation treatments. Thus, sheepshead minnows demonstrate two particularly different mechanisms towards dealing with thermal variation in low and high temperatures. The enzymatic differences between low and high cycling temperatures may define pathways of eurytolerant organisms and how they may survive predicted variability in thermal regimes.
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Aclimatação , Temperatura Baixa , Animais , Temperatura , Aclimatação/fisiologia , Peixes/fisiologia , Antioxidantes/metabolismo , Superóxido DismutaseRESUMO
Pseudomonas aeruginosa is a pathogen capable of colonizing virtually every human tissue. The host colonization competence and versatility of this pathogen are powered by a wide array of virulence factors necessary in different steps of the infection process. This includes factors involved in bacterial motility and attachment, biofilm formation, the production and secretion of extracellular invasive enzymes and exotoxins, the production of toxic secondary metabolites, and the acquisition of iron. Expression of these virulence factors during infection is tightly regulated, which allows their production only when they are needed. This process optimizes host colonization and virulence. In this work, we review the intricate network of transcriptional regulators that control the expression of virulence factors in P. aeruginosa, including one- and two-component systems and σ factors. Because inhibition of virulence holds promise as a target for new antimicrobials, blocking the regulators that trigger the production of virulence determinants in P. aeruginosa is a promising strategy to fight this clinically relevant pathogen.
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Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Virulência/genética , Pseudomonas aeruginosa/metabolismo , Fatores de Virulência/metabolismo , Exotoxinas/metabolismo , Percepção de Quorum , Biofilmes , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Pseudomonas/microbiologiaRESUMO
This paper examined how the amount (5% or 20%) and type (CaSO4 or Na2SO4) of sulphate salt affect the hydration of calcium sulphoaluminate clinker (KCSA). The mechanical behavior of the pastes was determined at 1, 3, 28, and 90 days, the heat flow and total heat were measured with isothermal conduction calorimetry, and the reaction products were characterized using X-ray diffraction (XRD), differential thermal analysis/thermogravimetry (DTA/TG) and scanning electron microscopy (SEM). The results obtained indicated that both the amount of sulphate salt (5% or 20%) and its type (CaSO4 or Na2SO4) affect the hydration kinetics, type of reaction products formed, and development of mechanical strength. The incorporation of CaSO4 has a positive effect on the development of the mechanical strength of KCSA. However, Na2SO4 can also produce adverse side effects at older ages. The presence of Na2SO4 increases pH values, which partly destabilizes the ettringite formed, thereby favoring carbonation and thenardite precipitation, which can cause the specimens to crack and break.
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BACKGROUND: This study describes the genotypic and phenotypic characterization of novel human cytomegalovirus (HCMV) genetic variants of a cohort of 94 clinically resistant HCMV patients. METHODS AND RESULTS: Antiviral-resistant mutations were detected in the UL97, UL54, and UL56 target genes of 25 of 94 (26.6%) patients. The genotype-phenotype correlation study resolved the status of 5 uncharacterized UL54 deoxyribonucleic acid polymerase (G441S, A543V, F460S, R512C, A928T) and 2 UL56 terminase (F345L, P800L) mutations found in clinical isolates. A928T conferred high, triple resistance to ganciclovir, foscarnet, and cidofovir, and A543V had 10-fold reduced susceptibility to cidofovir. Viral growth assays showed G441S, A543V, F345L, and P800L impaired viral growth capacities compared with wild-type AD169 HCMV. Three-dimensional modeling predicted A543V and A928T phenotypes but not R512C, reinforcing the need for individual characterization of mutations by recombinant phenotyping. CONCLUSIONS: Extending mutation databases is crucial to optimize treatments and to improve the assessment of patients with resistant/refractory HCMV infection.
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Infecções por Citomegalovirus , DNA Polimerase Dirigida por DNA , Humanos , Cidofovir/uso terapêutico , DNA Polimerase Dirigida por DNA/genética , Proteínas Virais/genética , Farmacorresistência Viral/genética , Ganciclovir/uso terapêutico , Citomegalovirus/genética , Antivirais/uso terapêutico , Fenótipo , MutaçãoRESUMO
The global risk of cardiovascular disease, including ischemic disease such as stroke, remains high, and cardiovascular disease is the cause of one-third of all deaths worldwide. The main subjacent cause, atherosclerosis, is not fully understood. To improve early diagnosis and therapeutic strategies, it is crucial to unveil the key molecular mechanisms that lead to atherosclerosis development. The field of epitranscriptomics is blossoming and quickly advancing in fields like cancer research, nevertheless, poorly understood in the context of cardiovascular disease. Epitranscriptomic modifications are shown to regulate the metabolism and function of RNA molecules, which are important for cell functions such as cell proliferation, a key aspect in atherogenesis. As such, epitranscriptomic regulatory mechanisms can serve as novel checkpoints in gene expression during disease development. In this review, we describe examples of the latest research investigating epitranscriptomic modifications, in particular A-to-I editing and the covalent modification N6-methyladenosine and their regulatory proteins, in the context of cardiovascular disease. We additionally discuss the potential of these mechanisms as therapeutic targets and novel treatment options.
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Aterosclerose , Doenças Cardiovasculares , Aterosclerose/genética , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/terapia , Epigênese Genética , Humanos , RNA/metabolismo , Processamento Pós-Transcricional do RNARESUMO
BACKGROUND: Vagococcus fluvialis is a species of lactic acid bacteria found both free-living in river and seawater and associated to hosts, such as marine sponges. This species has been greatly understudied, with no complete genome assembly available to date, which is essential for the characterisation of the mobilome. RESULTS: We sequenced and assembled de novo the complete genome sequences of five V. fluvialis isolates recovered from marine sponges. Pangenome analysis of the V. fluvialis species (total of 17 genomes) showed a high intraspecific diversity, with 45.5% of orthologous genes found to be strain specific. Despite this diversity, analyses of gene functions clustered all V. fluvialis species together and separated them from other sequenced Vagococcus species. V. fluvialis strains from different habitats were highly similar in terms of functional diversity but the sponge-isolated strains were enriched in several functions related to the marine environment. Furthermore, sponge-isolated strains carried a significantly higher number of mobile genetic elements (MGEs) compared to previously sequenced V. fluvialis strains from other environments. Sponge-isolated strains carried up to 4 circular plasmids each, including a 48-kb conjugative plasmid. Three of the five strains carried an additional circular extrachromosomal sequence, assumed to be an excised prophage as it contained mainly viral genes and lacked plasmid replication genes. Insertion sequences (ISs) were up to five times more abundant in the genomes of sponge-isolated strains compared to the others, including several IS families found exclusively in these genomes. CONCLUSIONS: Our findings highlight the dynamics and plasticity of the V. fluvialis genome. The abundance of mobile genetic elements in the genomes of sponge-isolated V. fluvialis strains suggests that the mobilome might be key to understanding the genomic signatures of symbiosis in bacteria.
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Poríferos , Animais , Enterococcaceae/genética , Sequências Repetitivas Dispersas/genética , Filogenia , Poríferos/genética , Análise de Sequência de DNARESUMO
Microtubules are part of the dynamic cytoskeleton network and composed of tubulin dimers. They are the main tracks used in cells to organize organelle positioning and trafficking of cargos. In this Review, we compile recent findings on the involvement of microtubules in anterograde protein transport. First, we highlight the importance of microtubules in organelle positioning. Second, we discuss the involvement of microtubules within different trafficking steps, in particular between the endoplasmic reticulum and the Golgi complex, traffic through the Golgi complex itself and in post-Golgi processes. A large number of studies have assessed the involvement of microtubules in transport of cargo from the Golgi complex to the cell surface. We focus here on the role of kinesin motor proteins and protein interactions in post-Golgi transport, as well as the impact of tubulin post-translational modifications. Last, in light of recent findings, we highlight the role microtubules have in exocytosis, the final step of secretory protein transport, occurring close to focal adhesions.
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Microtúbulos/metabolismo , Transporte Proteico/genética , HumanosRESUMO
SARS-CoV-2 infection causes an abrupt response by the host immune system, which is largely responsible for the outcome of COVID-19. We investigated whether the specific immune responses in the peripheral blood of 276 patients were associated with the severity and progression of COVID-19. At admission, dramatic lymphopenia of T, B, and NK cells is associated with severity. Conversely, the proportion of B cells, plasmablasts, circulating follicular helper T cells (cTfh) and CD56- CD16+ NK-cells increased. Regarding humoral immunity, levels of IgM, IgA, and IgG were unaffected, but when degrees of severity were considered, IgG was lower in severe patients. Compared to healthy donors, complement C3 and C4 protein levels were higher in mild and moderate, but not in severe patients, while the activation peptide of C5 (C5a) increased from the admission in every patient, regardless of their severity. Moreover, total IgG, the IgG1 and IgG3 isotypes, and C4 decreased from day 0 to day 10 in patients who were hospitalized for more than two weeks, but not in patients who were discharged earlier. Our study provides important clues to understand the immune response observed in COVID-19 patients, associating severity with an imbalanced humoral response, and identifying new targets for therapeutic intervention.
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Linfócitos B/imunologia , COVID-19/patologia , Imunoglobulinas/sangue , Células Matadoras Naturais/imunologia , SARS-CoV-2/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Idoso , COVID-19/imunologia , Complemento C3/análise , Complemento C4/análise , Complemento C5/análise , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Contagem de Linfócitos , Linfopenia/imunologia , Masculino , Pessoa de Meia-Idade , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/patologiaRESUMO
BACKGROUND: T-cell activation is associated with an adverse outcome in COVID-19, but whether T-cell activation and exhaustion relate to persistent respiratory dysfunction and death is unknown. OBJECTIVES: To investigate whether T-cell activation and exhaustion persist and are associated with prolonged respiratory dysfunction and death after hospitalization for COVID-19. METHODS: Plasma and serum from two Norwegian cohorts of hospitalized patients with COVID-19 (n = 414) were analyzed for soluble (s) markers of T-cell activation (sCD25) and exhaustion (sTim-3) during hospitalization and follow-up. RESULTS: Both markers were strongly associated with acute respiratory failure, but only sTim-3 was independently associated with 60-day mortality. Levels of sTim-3 remained elevated 3 and 12 months after hospitalization and were associated with pulmonary radiological pathology after 3 months. CONCLUSION: Our findings suggest prolonged T-cell exhaustion is an important immunological sequela, potentially related to long-term outcomes after severe COVID-19.