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Inflammasome-mediated caspase-1 activation facilitates innate immune control of Plasmodium in the liver, thereby limiting the incidence and severity of clinical malaria. However, caspase-1 processing occurs incompletely in both mouse and human hepatocytes and precludes the generation of mature IL-1ß or IL-18, unlike in other cells. Why this is so or how it impacts Plasmodium control in the liver has remained unknown. We show that an inherently reduced expression of the inflammasome adaptor molecule apoptosis-associated specklike protein containing CARD (ASC) is responsible for the incomplete proteolytic processing of caspase-1 in murine hepatocytes. Transgenically enhancing ASC expression in hepatocytes enabled complete caspase-1 processing, enhanced pyroptotic cell death, maturation of the proinflammatory cytokines IL-1ß and IL-18 that was otherwise absent, and better overall control of Plasmodium infection in the liver of mice. This, however, impeded the protection offered by live attenuated antimalarial vaccination. Tempering ASC expression in mouse macrophages, on the other hand, resulted in incomplete processing of caspase-1. Our work shows how caspase-1 activation and function in host cells are fundamentally defined by ASC expression and offers a potential new pathway to create better disease and vaccination outcomes by modifying the latter.
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Inflamassomos , Malária , Animais , Humanos , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/metabolismo , Hepatócitos/metabolismo , Inflamassomos/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismoRESUMO
Neutrophil recruitment to sites of infection and inflammation is an essential process in the early innate immune response. Upon activation, a subset of neutrophils rapidly assembles the multiprotein complex known as the NLRP3 inflammasome. The NLRP3 inflammasome forms at the microtubule organizing center, which promotes the formation of interleukin (IL)-1ß and IL-18, essential cytokines in the immune response. We recently showed that mice deficient in NLRP3 (NLRP3-/-) have reduced neutrophil recruitment to the peritoneum in a model of thioglycolate-induced peritonitis. Here, we tested the hypothesis that this diminished recruitment could be, in part, the result of defects in neutrophil chemotaxis. We find that NLRP3-/- neutrophils show loss of cell polarization, as well as reduced directionality and velocity of migration toward increasing concentrations of leukotriene B4 (LTB4) in a chemotaxis assay in vitro, which was confirmed through intravital microscopy of neutrophil migration toward a laser-induced burn injury of the liver. Furthermore, pharmacologically blocking NLRP3 inflammasome assembly with MCC950 in vitro reduced directionality but preserved nondirectional movement, indicating that inflammasome assembly is specifically required for polarization and directional chemotaxis, but not cell motility per se. In support of this, pharmacological breakdown of the microtubule cytoskeleton via nocodazole treatment induced cell polarization and restored nondirectional cell migration in NLRP3-deficient neutrophils in the LTB4 gradient. Therefore, NLRP3 inflammasome assembly is required for establishment of cell polarity to guide the directional chemotactic migration of neutrophils.
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Quimiotaxia , Leucotrieno B4 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Camundongos , Inflamassomos , Leucotrieno B4/metabolismo , Neutrófilos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismoRESUMO
Malaria, caused by Plasmodium parasites is a severe disease affecting millions of people around the world. Plasmodium undergoes obligatory development and replication in the hepatocytes, before initiating the life-threatening blood-stage of malaria. Although the natural immune responses impeding Plasmodium infection and development in the liver are key to controlling clinical malaria and transmission, those remain relatively unknown. Here we demonstrate that the DNA of Plasmodium parasites is sensed by cytosolic AIM2 (absent in melanoma 2) receptors in the infected hepatocytes, resulting in Caspase-1 activation. Remarkably, Caspase-1 was observed to undergo unconventional proteolytic processing in hepatocytes, resulting in the activation of the membrane pore-forming protein, Gasdermin D, but not inflammasome-associated proinflammatory cytokines. Nevertheless, this resulted in the elimination of Plasmodium-infected hepatocytes and the control of malaria infection in the liver. Our study uncovers a pathway of natural immunity critical for the control of malaria in the liver.
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Malária , Parasitos , Plasmodium , Animais , Humanos , Hepatócitos/metabolismo , Fígado , Malária/parasitologia , Caspases/metabolismo , Proteínas de Ligação a DNA/metabolismoRESUMO
The human cerebral cortex is one of the most evolved regions of the brain, responsible for most higher-order neural functions. Since nerve cells (together with synapses) are the processing units underlying cortical physiology and morphology, we studied how the human neocortex is composed regarding the number of cells as a function of sex and age. We used the isotropic fractionator for cell quantification of immunocytochemically labeled nuclei from the cerebral cortex donated by 43 cognitively healthy subjects aged 25-87 years old. In addition to previously reported sexual dimorphism in the medial temporal lobe, we found more neurons in the occipital lobe of men, higher neuronal density in women's frontal lobe, but no sex differences in the number and density of cells in the other lobes and the whole neocortex. On average, the neocortex has ~10.2 billion neurons, 34% in the frontal lobe and the remaining 66% uniformly distributed among the other 3 lobes. Along typical aging, there is a loss of non-neuronal cells in the frontal lobe and the preservation of the number of neurons in the cortex. Our study made possible to determine the different degrees of modulation that sex and age evoke on cortical cellularity.
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Córtex Cerebral , Neocórtex , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Lobo Temporal , Neurônios , Lobo Occipital/anatomia & histologia , Lobo Frontal/anatomia & histologia , Contagem de CélulasRESUMO
Environmental changes alter the sex fate in about 15% of vertebrate orders, mainly in ectotherms such as fish and reptiles. However, the effects of temperature changes on the endocrine and molecular processes controlling gonadal sex determination are not fully understood. Here, we provide evidence that thyroid hormones (THs) act as co-players in heat-induced masculinization through interactions with the stress axis to promote testicular development. We first demonstrated that the thyroid axis (through thyroid-related genes and T3 levels) is highly active in males during the gonadal development in medaka (Oryzias latipes). Similarly, T3 treatments promoted female-to-male sex reversal in XX embryos. Subsequently, embryonic exposure to temperature-induced stress up-regulated the genes related to the thyroid and stress axes with a final increase in T3 levels. In this context, we show that blocking the stress axis response by the loss of function of the corticotropin-releasing hormone receptors suppresses thyroid-stimulating hormone expression, therefore, heat-induced activation of the thyroid axis. Thus, our data showed that early activation of the stress axis and, in consequence, the TH axis, too, leaves us with that both being important endocrine players in inducing female-to-male reversal, which can help predict possible upcoming physiological impacts of global warming on fish populations.
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Temperatura Alta , Glândula Tireoide , Feminino , Masculino , Animais , Temperatura , Gônadas , Folhas de PlantaRESUMO
OBJECTIVE: The aim was to analyze the relationship between early sports participation (ESP) and body fatness (BF) in adults, as well as to identify whether this possible relationship is directly influenced by the current physical activity (PA) level. METHODS: This cross-sectional study combined baseline data of two cohort. The BF estimated by DXA. The ESP, the subjects reported the engagement in sports during childhood (7-10 years) and adolescence (11-17 years) through two yes/no questions and current PA (described as steps) was device-measured using pedometers. Were identified as potential covariates and therefore adjusted the multivariate models: age, ethnicity, alcohol consumption, smoking, and sleep quality. Statistical analysis consisted of the chi-square test, analysis of variance/covariance, and structural equation modeling (software BioEstat version 5.0; p-value < .05). RESULTS: Adults engaged in ESP had lower BF; among women, the variance in BF explained by ESP was 25.5%; among men, it was 9.2%. Sports participation in early life (r = -.436 [95% CI: -0.527 to -0.346]) and current PA (r = -.431 [95% CI: -0.522 to -0.340]) were inversely related to BF, as well as positively related to each other (r = .328 [95% CI: 0.226 to 0.430]). In the mediation model, current PA partially mediated (18.5%) the impact of ESP on BF, while current PA and ESP remained relevant determinants of BF. CONCLUSION: Early sports participation and current PA have a significant impact on BF in adulthood, which is of similar magnitude and independent of each other.
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Exercício Físico , Esportes , Masculino , Adulto , Adolescente , Humanos , Feminino , Estudos Transversais , Tecido Adiposo , EtnicidadeRESUMO
This study evaluated the oil content obtained from andiroba seeds by pressurized n-propane at different conditions of temperature (25, 35, and 45 °C) and pressure (40, 60, and 80 bar), and conventional extraction technique using n-hexane as the solvent. Kinetic extraction curves were fitted using Sovová's mathematical model. The chemical characterization of the oil was reported as well as the protein content in the extraction by-product. Pressurized extractions conducted at 25 °C provided the highest oil recovery (~45 wt%) from the seeds. The increase in pressure at 25 ºC favored obtaining oil with higher Stigmasterol contents, however, the Squalene content was higher in the oil obtained at 40 bar. The oils with the highest concentration phenolic compounds and antioxidant activity were obtained at 80 bar. Extraction with n-propane provided oils with higher levels of phenolic compounds, however, with antioxidant activity similar to conventional extraction. For all evaluated extractions, the product showed a predominance of oleic and palmitic acids, with similar values of oxidative stability. The extraction of the by-product with the highest soluble protein content was obtained under mild processing conditions (25 °C and 40 bar) with n-propane.
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Antioxidantes , Óleos de Plantas , Sementes , Sementes/química , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Óleos de Plantas/química , Temperatura , Pressão , Arecaceae/química , Hexanos/químicaRESUMO
Alternative diets for pets have gained attention in recent years due to concerns about sustainability and environmental impact. One emerging option is the inclusion of edible insects in pet food. This study aimed to survey dog (DO) and cat (CO) owners regarding their willingness to feed insect-based pet food (IBPF) to their pets and to identify potential motivating factors. A total of 435 valid responses were evaluated, with 66% being DO and 58% CO. Of those, 24% owned both dogs and cats. About half of DO (52%) and 62% of CO were positive about IBPF. CO had a higher acceptance of IBPF than DO (p < 0.05). Moreover, both DO and CO showed a significant increase in acceptance if IBPF has been proven to provide sustainable and nutritional benefits (p < 0.01). CO adhering to a specific diet themselves showed a significantly higher acceptance of IBPF (p < 0.05), however it was independent of the type of diet. Additionally, 32% of DO and 34% of CO reported prior experience with eating edible insects themselves, and a positive entomophagy experience increased DO's (p = 0.108) and CO's (p < 0.01) acceptance of IBPF. Furthermore, the interest in entomophagy resulted in increased acceptance of IBPF by both DO and CO who had not yet tried insects (p < 0.01). In conclusion, pet owners demonstrated a favourable perception of IBPF and showed a willingness to incorporate these products into their pets' diets. CO displayed a more positive perception compared to DO, suggesting a beneficial focus on the feline niche. To enhance overall acceptance, emphasizing sustainability and conducting further research to establish the nutritional benefits of IBPF are crucial. The findings of this study provide valuable insights for pet food manufacturers and marketers to develop strategies and products aligned with the preferences and needs of pet owners.
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We investigated the effects of replacing ground corn with full-fat corn germ (FFCG) on milk production, milk composition, and nutrient use in cows fed sugarcane bagasse and cactus cladodes. Ten multiparous Girolando cows (average body weight 500 ± 66 kg, 90 ± 15 days in milk) were distributed in a replicated 5 × 5 Latin Square and assigned to five dietary treatments containing 0%, 25%, 50%, 75%, or 100% of full-fat corn germ in substitution to ground corn. Full-fat corn germ increased fat-corrected milk yield by 2.2 kg/day and the synthesis of fat, lactose, and total solids in milk by 94.4, 60.0, and 201.10 g/day, respectively (p < 0.05). Cows fed corn germ quadratically increased (p < 0.05) dry matter intake by 1.01 kg/day, with the intake of crude protein and total digestible nutrients following the same pattern. Conversely, the substitution of corn for full-fat corn germ linearly reduced (p < 0.05) the total non-fiber carbohydrate intake from 5.79 to 4.40 kg/d. Except for ether extract and non-fiber carbohydrates, full-fat corn germ did not alter (p > 0.05) nutrient digestibility. Cows fed corn germ excreted less (p < 0.05) urea-N in milk and urine N. These results demonstrate that full-fat corn germ can partially replace ground corn to enhance the milk production efficiency of crossbred cows fed cactus cladodes and sugarcane bagasse. Furthermore, including sugarcane bagasse in FFCG-supplemented diets prevents milk fat depression in cows fed cactus cladodes.
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Cactaceae , Saccharum , Feminino , Bovinos , Animais , Leite/metabolismo , Celulose/metabolismo , Zea mays , Lactação , Dieta/veterinária , Carboidratos da Dieta/metabolismo , Digestão , Rúmen/metabolismo , Silagem/análiseRESUMO
BACKGROUND: The inflammation in the lungs and other vital organs in COVID-19 are characterized by the presence of neutrophils and high concentration of neutrophil extracellular traps (NETs), which also seems to mediate host tissue damage. However, it is not known whether NETs could have virucidal activity against SARS-CoV-2. METHODS: We investigated whether NETs could prevent SARS-CoV-2 replication in neutrophils and epithelial cells, and what the consequence of NETs degradation in K18-humanized ACE2 transgenic mice infected with SARS-CoV-2. RESULTS: Here, by immunofluorescence microscopy we observed that viral particles co-localize with NETs in neutrophils isolated from COVID-19 patients or from healthy individuals and infected in vitro. The inhibition of NETs production increased virus replication in neutrophils. In parallel, we observed that NETs inhibited virus abilities to infect and replicate in epithelial cells after 24â h of infection. Degradation of NETs with DNase I prevented their virucidal effect in vitro. Using K18-humanized ACE2 transgenic mice we observed a higher viral load in animals treated with DNase I. On the other hand, the virucidal effect of NETs was not dependent on neutrophil elastase or myeloperoxidase activity. CONCLUSION: Our results provide evidence of the role of NETosis as a mechanism of SARS-CoV-2 viral capture and inhibition.
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BACKGROUND: COVID-19 causes consequences such as imbalance of the immune system and thrombotic events. During the infection process, NETs in excess induce a pro-inflammatory response and disseminated intravascular coagulation. We evaluated the role of enoxaparin as a potential inhibitor of NETs. METHODS: K18-hACE2 animals infected with the SARS-CoV-2 virus and a group of 23 individuals admitted to the hospital with COVID-19 treated with enoxaparin or without treatment and controls without the disease were included. RESULTS: Enoxaparin decreased the levels of NETs, reduced the signs of the disease and mitigated lung damage in the animals infected with SARS-CoV-2. These effects were partially associated with prevention of SARS-CoV-2 entry and NETs synthesis. Clinical data revealed that treatment with enoxaparin decreased the levels of inflammatory markers, the levels of NETs in isolated neutrophils and the organ dysfunction. CONCLUSION: This study provides evidence for the beneficial effects of enoxaparin in COVID-19 in addition to its anticoagulant role.
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COVID-19 , Armadilhas Extracelulares , Humanos , Animais , Neutrófilos , Enoxaparina/farmacologia , SARS-CoV-2RESUMO
Multiple organ dysfunction is the most severe outcome of sepsis progression and is highly correlated with a worse prognosis. Excessive neutrophil extracellular traps (NETs) are critical players in the development of organ failure during sepsis. Therefore, interventions targeting NET release would likely effectively prevent NET-based organ injury associated with this disease. Herein, we demonstrate that the pore-forming protein gasdermin D (GSDMD) is active in neutrophils from septic humans and mice and plays a crucial role in NET release. Inhibition of GSDMD with disulfiram or genic deletion abrogated NET formation, reducing multiple organ dysfunction and sepsis lethality. Mechanistically, we demonstrate that during sepsis, activation of the caspase-11/GSDMD pathway controls NET release by neutrophils during sepsis. In summary, our findings uncover a novel therapeutic use for disulfiram and suggest that GSDMD is a therapeutic target to improve sepsis treatment.
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Armadilhas Extracelulares/genética , Deleção de Genes , Peptídeos e Proteínas de Sinalização Intracelular/genética , Insuficiência de Múltiplos Órgãos/genética , Proteínas de Ligação a Fosfato/genética , Sepse/genética , Inibidores de Acetaldeído Desidrogenases/uso terapêutico , Transferência Adotiva , Idoso , Animais , Células Cultivadas , Dissulfiram/uso terapêutico , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/patologia , Insuficiência de Múltiplos Órgãos/terapia , Proteínas de Ligação a Fosfato/antagonistas & inibidores , Sepse/patologia , Sepse/terapiaRESUMO
Antimicrobial drugs are of great importance in the control of bacterial infections. Its indiscriminate use contributes to the consolidation of bacterial resistance. Its applicability is due to its secondary metabolites, such as saponins, which are compounds with relevant antibacterial action. Hecogenin acetate is a saponin present in plants of the agave genus with analgesic, antioxidant, antinociceptive, cardioactive, anticancer, antifungal and antimicrobial activity. The present work aimed to identify the antibacterial activity of hecogenin acetate against strains of E. coli, P. aeruginosa and S. aureus and to investigate the NorA and MepA efflux pump inhibitory activity of S. aureus strains. The Minimum Inhibitory Concentration was evaluated by broth microdilution. The Antibiotic Activity Modifier effect and the assessment of efflux pump inhibition were evaluated by microdilution with sub-inhibitory concentrations. Hecogenin acetate showed minimal inhibitory concentration without significant relevance. In the evaluation of the potentiating activity of the antibiotic action, a greater antagonistic behavior is noticed. In the analyzes performed with the efflux pump, it was noticed that the hecogenin acetate does not interfere in the efflux pump mechanism of the analyzed bacteria.
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Antibacterianos , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Staphylococcus aureus , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Testes de Sensibilidade Microbiana , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismoRESUMO
BACKGROUND: COVID-19 is characterized by severe acute lung injury, which is associated with neutrophil infiltration and the release of neutrophil extracellular traps (NETs). COVID-19 treatment options are scarce. Previous work has shown an increase in NETs release in the lung and plasma of COVID-19 patients suggesting that drugs that prevent NETs formation or release could be potential therapeutic approaches for COVID-19 treatment. METHODS: Here, we report the efficacy of NET-degrading DNase I treatment in a murine model of COVID-19. SARS-CoV-2-infected K18-hACE2 mice were performed for clinical sickness scores and lung pathology. Moreover, the levels of NETs were assessed and lung injuries were by histopathology and TUNEL assay. Finally, the injury in the heart and kidney was assessed by histopathology and biochemical-specific markers. RESULTS: DNase I decreased detectable levels of NETs, improved clinical disease, and reduced lung, heart, and kidney injuries in SARS-CoV-2-infected K18-hACE2 mice. Furthermore, our findings indicate a potentially deleterious role for NETs lung tissue in vivo and lung epithelial (A549) cells in vitro, which might explain part of the pathophysiology of severe COVID-19. This deleterious effect was diminished by the treatment with DNase I. CONCLUSIONS: Together, our results support the role of NETs in COVID-19 immunopathology and highlight NETs disruption pharmacological approaches as a potential strategy to ameliorate COVID-19 clinical outcomes.
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Lesão Pulmonar Aguda , COVID-19 , Armadilhas Extracelulares , Animais , Humanos , Camundongos , SARS-CoV-2 , Tratamento Farmacológico da COVID-19 , Modelos Animais de Doenças , Neutrófilos , Desoxirribonuclease I/farmacologia , Desoxirribonuclease I/uso terapêuticoRESUMO
OBJECTIVE: To determine whether a combination of a single intramuscular (IM) dose of pentamidine (7 mg/kg) followed by oral tamoxifen 40 mg/day for 20 days is non-inferior to three IM doses of pentamidine 7 mg/kg in the treatment of cutaneous leishmaniasis with a margin of 15%. METHODS: Phase II, randomised, controlled, open-label, non-inferiority clinical trial. Primary outcome was the complete healing of the lesions 6 months after starting treatment. Secondary outcomes were healing 3 months after starting treatment and determining the presence and severity of adverse effects (AE). RESULTS: The research was concluded with 49 patients; Leishmania (Viannia) guyanensis was the most frequent species isolated. In the primary outcome, 18 (72%) (95% CI: 52.4%-85.7%) of the 25 patients allocated to the intervention group and 24 (100%) (95% CI: 86.2%-100%) of the control group (p = 0.015) met the established criteria of cure. There was no AE with tamoxifen. CONCLUSION: Although a 72% cure rate presented by the combination of tamoxifen and pentamidine was lower than in the control group that achieved a 100% cure, it is still a safe and is a clinically relevant result. It indicates that the therapeutic scheme evaluated may be a promising option for populations in remote areas, however it should be further studied, in order to include a larger number of patients.
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Antiprotozoários , Leishmania guyanensis , Leishmaniose Cutânea , Humanos , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/patologia , Pentamidina/uso terapêutico , Tamoxifeno/uso terapêuticoRESUMO
OBJECTIVE: This study aimed to investigate the effects of FK506 on experimental sepsis immunopathology. It investigated the effect of FK506 on leukocyte recruitment to the site of infection, systemic cytokine production, and organ injury in mice with sepsis. METHODS: Using a murine cecal ligation and puncture (CLP) peritonitis model, the experiments were performed with wild-type (WT) mice and mice deficient in the gene Nfat1 (Nfat1-/-) in the C57BL/6 background. Animals were treated with 2.0 mg/kg of FK506, subcutaneously, 1 h before the sepsis model, twice a day (12 h/12 h). The number of bacteria colony forming units (CFU) was manually counted. The number of neutrophils in the lungs was estimated by the myeloperoxidase (MPO) assay. The expression of CXCR2 in neutrophils was determined using flow cytometry analysis. The expression of inflammatory cytokines in macrophage was determined using ELISA. The direct effect of FK506 on CXCR2 internalization was evaluated using HEK-293T cells after CXCL2 stimulation by the BRET method. RESULTS: FK506 treatment potentiated the failure of neutrophil migration into the peritoneal cavity, resulting in bacteremia and an exacerbated systemic inflammatory response, which led to higher organ damage and mortality rates. Failed neutrophil migration was associated with elevated CXCL2 chemokine plasma levels and lower expression of the CXCR2 receptor on circulating neutrophils compared with non-treated CLP-induced septic mice. FK506 did not directly affect CXCL2-induced CXCR2 internalization by transfected HEK-293 cells or mice neutrophils, despite increasing CXCL2 release by LPS-treated macrophages. Finally, the CLP-induced response of Nfat1-/- mice was similar to those observed in the Nfat1+/+ genotype, suggesting that the FK506 effect is not dependent on the NFAT1 pathway. CONCLUSION: Our data indicate that the increased susceptibility to infection of FK506-treated mice is associated with failed neutrophil migration due to the reduced membrane availability of CXCR2 receptors in response to exacerbated levels of circulating CXCL2.
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Neutrófilos , Sepse , Humanos , Camundongos , Animais , Tacrolimo/farmacologia , Tacrolimo/uso terapêutico , Células HEK293 , Camundongos Endogâmicos C57BL , Sepse/metabolismo , Infiltração de NeutrófilosRESUMO
Tar spot, a disease caused by the ascomycete fungal pathogen Phyllachora maydis, is considered one of the most significant yield-limiting diseases of maize (Zea mays L.) within the United States. P. maydis may also be found in association with other fungi, forming a disease complex which is thought to result in the characteristic fish eye lesions. Understanding how P. maydis colonizes maize leaf cells is essential for developing effective disease control strategies. Here, we used histological approaches to elucidate how P. maydis infects and multiplies within susceptible maize leaves. We collected tar spot-infected maize leaf samples from four different fields in northern Indiana at three different time points during the growing season. Samples were chemically fixed and paraffin-embedded for high-resolution light and scanning electron microscopy. We observed a consistent pattern of disease progression in independent leaf samples collected across different geographical regions. Each stroma contained a central pycnidium that produced asexual spores. Perithecia with sexual spores developed in the stomatal chambers adjacent to the pycnidium, and a cap of spores formed over the stroma. P. maydis reproductive structures formed around but not within the vasculature. We observed P. maydis associated with two additional fungi, one of which is likely a member of the Paraphaeosphaeria genus; the other is an unknown fungi. Our data provide fundamental insights into how this pathogen colonizes and spreads within maize leaves. This knowledge can inform new approaches to managing tar spot, which could help mitigate the significant economic losses caused by this disease.
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Our previous study showed that sodium arsenite (200 mg/L) affected the nervous system and induced motor neuron development via the Sonic hedgehog pathway in zebrafish larvae. To gain more insight into the effects of arsenite on other signaling pathways, including apoptosis, we have performed quantitative polymerase chain reaction array-based gene expression analyses. The 96-well array plates contained primers for 84 genes representing 10 signaling pathways that regulate several biological functions, including apoptosis. We exposed eggs at 5 h postfertilization until the 72 h postfertilization larval stage to 200 mg/L sodium arsenite. In the Janus kinase/signal transducers and activators of transcription, nuclear factor κ-light-chain-enhancer of activated B cells, and Wingless/Int-1 signaling pathways, the expression of only one gene in each pathway was significantly altered. The expression of multiple genes was altered in the p53 and oxidative stress pathways. Sodium arsenite induced excessive apoptosis in the larvae. This compelled us to analyze specific genes in the p53 pathway, including cdkn1a, gadd45aa, and gadd45ba. Our data suggest that the p53 pathway is likely responsible for sodium arsenite-induced apoptosis. In addition, sodium arsenite significantly reduced global DNA methylation in the zebrafish larvae, which may indicate that epigenetic factors could be dysregulated after arsenic exposure. Together, these data elucidate potential mechanisms of arsenic toxicity that could improve understanding of arsenic's effects on human health.
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Arsênio , Arsenitos , Animais , Humanos , Peixe-Zebra/genética , Arsênio/toxicidade , Proteína Supressora de Tumor p53 , Proteínas Hedgehog/farmacologia , Arsenitos/toxicidade , Perfilação da Expressão Gênica , ApoptoseRESUMO
The experiments reported in this research paper address the effects of replacing ground corn (GC) with full-fat corn germ (FFCG) on nutrient intake and digestibility, nitrogen utilization efficiency, performance, and predicted methane production in dairy cows fed cactus cladodes and sugarcane. We hypothesized that the inclusion of FFCG in the diet would not alter the performance of lactating cows but would reduce the predicted methane production in vivo. Ten multiparous Holstein cows at 90 ± 10 d of lactation and yielding 24.2 ± 3.5 kg milk/d were assigned to dietary treatments consisting of different levels of replacement of GC by FFCG (0; 25; 50; 75 and 100% of diet dry matter) in a replicated 5 × 5 Latin square design with 21-d periods. Methane production was predicted using an automated gas in vitro production system. Except for ether extract intake, which increased, the intake of all nutrients decreased linearly with the replacement of GC by FFCG. The digestibility of dry matter, organic matter and neutral detergent fiber reduced, whereas the digestibility of ether extract increased linearly with FFCG. There were no changes in the digestibility of crude protein. The nitrogen intake and daily excretion in urine and feces decreased, while nitrogen use efficiency increased linearly. There was no significant effect of diets on nitrogen balance or microbial protein synthesis and efficiency. The yield of protein, lactose and total solids in milk showed a quadratic behavior. On the other hand, milk fat yield and energy-corrected milk yield decreased linearly with the replacement of GC by FFCG. No effect on pH or ammonia nitrogen was observed. The production of methane (CH4, g/kg DM) and total CH4 (g/d), and CH4 intensity decreased linearly with the replacement of GC by FFCG. In conclusion, FFCG has been shown to be an effective source of fat to reduce methane production in dairy cows, partially supporting our initial hypothesis. However, as it decreases milk fat production, it is not recommended to replace more than 50% of GC by FFCG for lactating cows fed cactus cladodes and sugarcane.
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Lactação , Zea mays , Feminino , Bovinos , Animais , Zea mays/metabolismo , Digestão , Silagem/análise , Fibras na Dieta/metabolismo , Leite/metabolismo , Dieta/veterinária , Metano/metabolismo , Nitrogênio/metabolismo , Extratos Vegetais , RúmenRESUMO
COPD, one of world's leading contributors to morbidity and mortality, is characterized by airflow limitation and heterogeneous clinical features. Three main phenotypes are proposed: overlapping asthma/COPD (ACO), exacerbator, and emphysema. Disease severity can be classified as mild, moderate, severe, and very severe. The molecular basis of inflammatory amplification, cellular aging, and immune response are critical to COPD pathogenesis. Our aim was to investigate EP300 (histone acetylase, HAT), HDAC 2 (histone deacetylase), HDAC3, and HDAC4 gene expression, telomere length, and differentiation ability to M1/M2 macrophages. For this investigation, 105 COPD patients, 42 smokers, and 73 non-smoker controls were evaluated. We identified a reduced HDAC2 expression in patients with mild, moderate, and severe severity; a reduced HDAC3 expression in patients with moderate and severe severity; an increased HDAC4 expression in patients with mild severity; and a reduced EP300 expression in patients with severe severity. Additionally, HDAC2 expression was reduced in patients with emphysema and exacerbator, along with a reduced HDAC3 expression in patients with emphysema. Surprisingly, smokers and all COPD patients showed telomere shortening. COPD patients showed a higher tendency toward M2 markers. Our data implicate genetic changes in COPD phenotypes and severity, in addition to M2 prevalence, that might influence future treatments and personalized therapies.