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1.
Brief Bioinform ; 24(3)2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37139555

RESUMO

Circular RNAs (circRNAs) are single-stranded and covalently closed non-coding RNA molecules originated from RNA splicing. Their functions include regulatory potential over other RNA species, such as microRNAs, messenger RNAs and RNA binding proteins. For circRNA identification, several algorithms are available and can be classified in two major types: pseudo-reference-based and split-alignment-based approaches. In general, the data generated from circRNA transcriptome initiatives is deposited on public specific databases, which provide a large amount of information on different species and functional annotations. In this review, we describe the main computational resources for the identification and characterization of circRNAs, covering the algorithms and predictive tools to evaluate its potential role in a particular transcriptomics project, including the public repositories containing relevant data and information for circRNAs, recapitulating their characteristics, reliability and amount of data reported.


Assuntos
MicroRNAs , RNA Circular , RNA Circular/metabolismo , Reprodutibilidade dos Testes , RNA/genética , RNA/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Splicing de RNA , Biologia Computacional
2.
Br J Haematol ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39021060

RESUMO

Uncertainty remains regarding the safety and tolerability of immunosuppressive therapy (IST) with anti-thymocyte globulin (ATG) and cyclosporine (CSA) in older patients. We retrospectively analysed two prospective clinical trials of IST in treatment-naïve severe aplastic anaemia (SAA) to assess safety in older compared to younger patients. Patients ≥18 years of age who had received IST with ATG and CSA +/- eltrombopag (EPAG) were included. Pre-treatment baseline characteristics and co-morbidities were assessed as predictors of therapy-related complications in younger (<60 years) versus older (≥60 years) patients. Out of 245 eligible patients, 54 were older and 191 were younger. Older patients had a similar frequency of SAEs, ICU admissions and hospital length of stay compared to younger patients. Older patients had a higher frequency of cardiac events related to IST, but none resulted in death. Older patients had worse long-term overall survival, and more relapse and clonal evolution post-IST. However, older patients who responded to IST had a similar survival at a median follow-up to younger patients. Disease-related factors and limited therapeutic options in refractory disease likely contribute to poorer outcomes in older patients, not complications of upfront IST. Therefore, IST should be considered first-line therapy for most older SAA patients.

3.
Br J Haematol ; 204(6): 2287-2300, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38651345

RESUMO

Despite advancements in utilizing genetic markers to enhance acute myeloid leukaemia (AML) outcome prediction, significant disease heterogeneity persists, hindering clinical management. To refine survival predictions, we assessed the transcriptome of non-acute promyelocytic leukaemia chemotherapy-treated AML patients from five cohorts (n = 975). This led to the identification of a 4-gene prognostic index (4-PI) comprising CYP2E1, DHCR7, IL2RA and SQLE. The 4-PI effectively stratified patients into risk categories, with the high 4-PI group exhibiting TP53 mutations and cholesterol biosynthesis signatures. Single-cell RNA sequencing revealed enrichment for leukaemia stem cell signatures in high 4-PI cells. Validation across three cohorts (n = 671), including one with childhood AML, demonstrated the reproducibility and clinical utility of the 4-PI, even using cost-effective techniques like real-time quantitative polymerase chain reaction. Comparative analysis with 56 established prognostic indexes revealed the superior performance of the 4-PI, highlighting its potential to enhance AML risk stratification. Finally, the 4-PI demonstrated to be potential marker to reclassified patients from the intermediate ELN2017 category to the adverse category. In conclusion, the 4-PI emerges as a robust and straightforward prognostic tool to improve survival prediction in AML patients.


Assuntos
Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/diagnóstico , Masculino , Feminino , Prognóstico , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Adulto , Idoso , Transcriptoma , Adolescente , Criança
4.
Mol Cell Biochem ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536555

RESUMO

Evidence for folate's protective effects on neural tube defects led the USA and Chile to start mandatory folic acid (FA) fortification programs, decreasing up to 50%. However, ∼30% of the population consuming fortified foods reach supraphysiologic serum levels. Although controversial, several epidemiological and clinical observations suggest that folate increases cancer risk, giving concern about the risks of FA supplementation. The Cancer stem cells (CSCs) model has been used to explain survival to anticancer therapies. The Notch-1 pathway plays a role in several cancers and is associated with the stemness process. Different studies show that modulation of metabolic pathways regulates stemness capacity in cancer. Supraphysiologic concentrations of FA increase the proliferation of HT-29 cells by Notch-1 activation. However, whether folate can induce a stemness-like phenotype in cancer is not known. We hypothesized that FA protects from glucose deprivation-induced cell death through Notch-1 activation. HT-29 cells were challenged with glucose deprivation at basal (20 nM) and supraphysiological (400 nM) FA and 5-MTHF concentrations. We analyzed changes in stemness-like gene expression, cell death and different energetic metabolic functions. Supraphysiological concentrations of FA increased stemness-like genes, and improved survival and oxygen consumption, inducing AMPK phosphorylation and HSP-70 protein expression. We evaluated the Notch-1 pathway using the DAPT and siRNA as inhibitors, decreasing the stemness-like gene expression and preventing the FA protection against glucose deprivation-induced cell death. Moreover, they decreased oxygen consumption and AMPK phosphorylation. These results suggest that FA protects against glucose deprivation. These effects were associated with AMPK activation, a critical metabolic mediator in nutrient consumption and availability that activates the Notch-1 pathway.

5.
Am J Primatol ; 86(7): e23638, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38715239

RESUMO

Phenolics, like tannins, are plant-specialized metabolites that play a protective role against herbivory. Tannins can reduce palatability and bind with proteins to reduce digestibility, acting as deterrents to feeding and impacting nutrient extraction by herbivores. Some assays measure tannin and total phenolics content in plants but lack determination of their biological effects, hindering the interpretation of tannin function in herbivory and its impacts on animal behavior and ecology. In this study, we successfully applied the radial diffusion assay to assess tannin protein precipitation (PP) capacity and evaluate the anti-nutritional effects of tannins in food plants (n = 24) consumed by free-ranging black howler monkeys (Alouatta pigra) in Tabasco, Mexico. We found PP rings in five plant species consumed by the monkeys. The mature fruit of Inga edulis was the most consumed food plant, despite having a high tannin PP capacity (56.66 mg tannic acid equivalent/g dry matter). These findings highlight the presence of tannins in the black howler diet and provide insight into the primates' resilience and potential strategies for coping with anti-nutritional aspects of the diet.


Assuntos
Alouatta , Dieta , Preferências Alimentares , Taninos , Animais , Taninos/análise , Alouatta/fisiologia , Dieta/veterinária , México , Masculino , Feminino
6.
Am J Primatol ; 86(4): e23600, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38263846

RESUMO

Efficiently detecting early environmental threats to wildlife is vital for conservation. Beyond obvious dangers like habitat loss or deforestation, our study focuses on one of the most hazardous toxic metals for wildlife: lead (Pb). Pb is a widespread, cumulative, and insidious environmental pollutant that can trigger a wide range of physiological, biochemical, and behavioral disorders. In fact, Pb can cause permanent dysfunction of the major stress system, the hypothalamic pituitary adrenal (HPA) axis. We analyzed Pb and cortisol concentrations in fecal samples from Alouatta pigra in southern Mexico. Fecal samples were collected across six sites categorized as free-ranging (n = 65; conserved and disturbed) and from captive animals (n = 58). Additionally, we collected soil samples (n = 35). We found that Pb was present in 28% of fecal samples and 83% of soil samples. There was a positive relation between fecal and soil Pb levels, and fecal Pb concentration was negatively associated with cortisol levels. However, the claim of Pb being a direct interference with HPA axis requires further investigation. Given our findings, assessing wildlife exposure can be a valuable tool for understanding potential Pb exposure levels in the environment and its possible implications for human health. It can also serve as an early warning system of these consequences.


Assuntos
Alouatta , Chumbo , Humanos , Animais , Hidrocortisona , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Animais Selvagens , Alouatta/fisiologia , Solo , México
7.
Br J Haematol ; 200(2): 170-174, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36263593

RESUMO

Although a growing body of evidence demonstrates that altered mtDNA content (mtDNAc) has clinical implications in several types of solid tumours, its prognostic relevance in acute promyelocytic leukaemia (APL) patients remains largely unknown. Here, we show that patients with higher-than-normal mtDNAc had better outcomes regardless of tumour burden. These results were more evident in patients with low-risk of relapse. The multivariate Cox proportional hazard model demonstrated that high mtDNAc was independently associated with a decreased cumulative incidence of relapse. Altogether, our data highlights the possible role of mitochondrial metabolism in APL patients treated with ATRA.


Assuntos
Leucemia Promielocítica Aguda , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Tretinoína/uso terapêutico , DNA Mitocondrial/genética , Relevância Clínica , Recidiva Local de Neoplasia/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resultado do Tratamento
8.
Sensors (Basel) ; 23(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36772092

RESUMO

Ransomware-related cyber-attacks have been on the rise over the last decade, disturbing organizations considerably. Developing new and better ways to detect this type of malware is necessary. This research applies dynamic analysis and machine learning to identify the ever-evolving ransomware signatures using selected dynamic features. Since most of the attributes are shared by diverse ransomware-affected samples, our study can be used for detecting current and even new variants of the threat. This research has the following objectives: (1) Execute experiments with encryptor and locker ransomware combined with goodware to generate JSON files with dynamic parameters using a sandbox. (2) Analyze and select the most relevant and non-redundant dynamic features for identifying encryptor and locker ransomware from goodware. (3) Generate and make public a dynamic features dataset that includes these selected parameters for samples of different artifacts. (4) Apply the dynamic feature dataset to obtain models with machine learning algorithms. Five platforms, 20 ransomware, and 20 goodware artifacts were evaluated. The final feature dataset is composed of 2000 registers of 50 characteristics each. This dataset allows for a machine learning detection with a 10-fold cross-evaluation with an average accuracy superior to 0.99 for gradient boosted regression trees, random forest, and neural networks.

9.
Folia Primatol (Basel) ; 94(4-6): 265-275, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-38593405

RESUMO

The primates of Mexico, Ateles geoffroyi, Alouatta palliata, and Alouatta pigra, are seriously threatened by habitat loss, fragmentation, and illegal hunting and trade. Very little is known about the extent of illegal trade and its impacts on declining primate populations. Our study proposes a potential method based on estimating the number of individuals that die in the trade before being detected and those that probably cannot be detected. This facilitates estimating the number of animals extracted and allows an assessment of how trafficking impacts their populations. We derive estimates from seizure data of primates in Mexico between 2010 and 2019. To do this, we created wildlife detection rates and mortality rates from the existing literature (scientific articles, journalistic articles, and notes) to estimate the number of primates that die during capture, transport, and sale and the number of trafficked primates that were not detected by Mexican authorities. We estimate that 946 primates were removed from the wild for the pet trade each year (spider monkey Ateles geoffroyi = 854; black howler monkeys Alouatta pigra = 38, mantled howler monkey Alouatta palliata = 54). The annual reduction in population size caused by trafficking was greatest for Ateles geoffroyi (2.2%), followed by Alouatta pigra (1.3%), and Alouatta palliata (0.4%). Our estimates show the percentage of impacts that trafficking has on Mexican primate populations. Nevertheless, trade has the potential to impact declining populations and still must be addressed.


Assuntos
Alouatta , Ateles geoffroyi , Atelinae , Animais , Animais Selvagens , México
10.
Gac Med Mex ; 159(1): 32-37, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36930548

RESUMO

INTRODUCTION: Whether vitamin B12 deficiency is associated with cognitive impairment remains controversial. OBJECTIVE: To determine the association between vitamin B12 serum levels and cognitive performance. METHODS: Two-hundred and forty-one adults aged ≥ 60 years who had serum vitamin B12 serum levels measurement were included. Physical and cognitive evaluation was carried out, and three groups were formed: normal cognition (NC), mild cognitive impairment (MCI) and dementia. Vitamin B12 levels were classified as sufficiency (> 400 pg/mL), subclinical deficiency (201-400 pg/mL), and absolute deficiency (≤ 200 pg/mL). Multivariate linear regression analysis was used to evaluate the association between cognitive function and vitamin B12 levels after controlling for confounding variables. RESULTS: Mean age was 81.4 ± 8.0 years; 68% were females; 17.8 % and 39.8% had absolute and subclinical vitamin B12 deficiency, respectively; 80 individuals (33%) met the criteria for MCI, and 70 (29%), for dementia. Those with MCI and dementia had lower vitamin B12 levels in comparison with those with NC after adjusting for age, gender and educational level (p = 0.019). CONCLUSIONS: A statistically significant association was observed between global cognitive performance and levels of vitamin B12.


INTRODUCCIÓN: Aún es controversial si la deficiencia de vitamina B12 se asocia a alteraciones cognitivas. OBJETIVO: Conocer la asociación entre los niveles séricos de vitamina B12 y el desempeño cognitivo. MÉTODOS: Se incluyeron 241 personas ≥ 60 años con medición de niveles séricos de vitamina B12. Se realizó evaluación física y cognitiva y se formaron tres grupos: cognición normal (CN), deterioro cognitivo leve (DCL) y demencia. Los niveles de vitamina B12 se clasificaron en suficiencia (> 400 pg/mL), deficiencia subclínica (201-400 pg/mL) y deficiencia absoluta (≤ 200 pg/mL). Se realizó análisis de regresión lineal multivariado para evaluar la asociación entre función cognitiva y niveles de vitamina B12 después de controlar las variables confusoras. RESULTADOS: La media de edad fue 81.4 ± 8.0 años; 68 % fue del sexo femenino; 17.8 y 39.8 % presentaron deficiencia absoluta y subclínica de vitamina B12; 80 individuos (33 %) cumplieron los criterios de DCL y 70 (29 %), de demencia. Después de ajustar por edad, sexo y escolaridad, los sujetos con DCL y demencia tuvieron niveles más bajos de vitamina B12 comparados con aquellos con CN (p = 0.019). CONCLUSIONES: Se observó asociación estadísticamente significativa entre el desempeño cognitivo global y los niveles bajos de vitamina B12.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Demência , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Masculino , Vitamina B 12 , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Cognição , Demência/epidemiologia , Demência/etiologia , Vitaminas
11.
Cancer Sci ; 113(2): 597-608, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34808021

RESUMO

Several lines of research suggest that Bcl-xL-mediated anti-apoptotic effects may contribute to the pathogenesis of myeloproliferative neoplasms driven by JAK2V617F and serve as therapeutic target. Here, we used a knock-in JAK2V617F mouse model and confirmed that Bcl-xL was overexpressed in erythroid progenitors. The myeloproliferative neoplasm (MPN)-induced phenotype in the peripheral blood by conditional knock-in of JAK2V617F was abrogated by conditional knockout of Bcl2l1, which presented anemia and thrombocytopenia independently of JAK2 mutation status. Mx1-Cre Jak2V617W/VF /Bcl2l1f/f mice presented persistent splenomegaly as a result of extramedullary hematopoiesis and pro-apoptotic stimuli in terminally differentiated erythroid progenitors. The pan-BH3 mimetic inhibitor obatoclax showed superior cytotoxicity in JAK2V617F cell models, and reduced clonogenic capacity in ex vivo assay using Vav-Cre Jak2V617F bone marrow cells. Both ruxolitinib and obatoclax significantly reduced spleen weights in a murine Jak2V617F MPN model but did not show additive effect. The tumor burden reduction was observed with either ruxolitinib or obatoclax in terminal differentiation stage neoplastic cells but not in myeloid-erythroid precursors. Therefore, disrupting the BCL2 balance is not sufficient to treat MPN at the stem cell level, but it is certainly an additional option for controlling the critical myeloid expansion of the disease.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Janus Quinase 2/antagonistas & inibidores , Transtornos Mieloproliferativos/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Células Precursoras Eritroides/patologia , Humanos , Indóis/uso terapêutico , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Camundongos , Mutação , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Nitrilas/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Carga Tumoral/efeitos dos fármacos , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
12.
Invest New Drugs ; 40(3): 576-585, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35015172

RESUMO

BACKGROUND: Myeloproliferative neoplasms (MPN) are disorders characterized by an alteration at the hematopoietic stem cell (HSC) level, where the JAK2 mutation is the most common genetic alteration found in classic MPN (polycythemia vera, essential thrombocythemia, and primary myelofibrosis). We and others previously demonstrated that metformin reduced splenomegaly and platelets counts in peripheral blood in JAK2V617F pre-clinical MPN models, which highlighted the antineoplastic potential of biguanides for MPN treatment. Phenformin is a biguanide that has been used to treat diabetes, but was withdrawn due to its potential to cause lactic acidosis in patients. AIMS: We herein aimed to investigate the effects of phenformin in MPN disease burden and stem cell function in Jak2V617F-knockin MPN mice. RESULTS: In vitro phenformin treatment reduced cell viability and increased apoptosis in SET2 JAK2V67F cells. Long-term treatment with 40 mg/kg phenformin in Jak2V617F knockin mice increased the frequency of LSK, myeloid progenitors (MP), and multipotent progenitors (MPP) in the bone marrow. Phenformin treatment did not affect peripheral blood counts, spleen weight, megakaryocyte count, erythroid precursors frequency, or ex vivo clonogenic capacity. Ex vivo treatment of bone marrow cells from Jak2V617F knockin mice with phenformin did not affect hematologic parameters or engraftment in recipient mice. CONCLUSIONS: Phenformin increased the percentages of LSK, MP, and MPP populations, but did not reduce disease burden in Jak2V617F-knockin mice. Additional studies are necessary to further understand the effects of phenformin on early hematopoietic progenitors.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Animais , Medula Óssea , Modelos Animais de Doenças , Humanos , Janus Quinase 2 , Camundongos , Mutação , Transtornos Mieloproliferativos/tratamento farmacológico , Fenformin/farmacologia , Fenformin/uso terapêutico , Policitemia Vera/genética
13.
Invest New Drugs ; 40(2): 438-452, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34837603

RESUMO

Stathmin 1 (STMN1) is a microtubule-destabilizing protein highly expressed in hematological malignancies and involved in proliferation and differentiation. Although a previous study found that the PML-RARα fusion protein, which contributes to the pathophysiology of acute promyelocytic leukemia (APL), positively regulates STMN1 at the transcription and protein activity levels, little is known about the role of STMN1 in APL. In this study, we aimed to investigate the STMN1 expression levels and their associations with laboratory, clinical, and genomic data in APL patients. We also assessed the dynamics of STMN1 expression during myeloid cell differentiation and cell cycle progression, and the cellular effects of STMN1 silencing and pharmacological effects of microtubule-stabilizing drugs on APL cells. We found that STMN1 transcripts were significantly increased in samples from APL patients compared with those of healthy donors (all p < 0.05). However, this had no effect on clinical outcomes. STMN1 expression was associated with proliferation- and metabolism-related gene signatures in APL. Our data confirmed that STMN1 was highly expressed in early hematopoietic progenitors and reduced during cell differentiation, including the ATRA-induced granulocytic differentiation model. STMN1 phosphorylation was predominant in a pool of mitosis-enriched APL cells. In NB4 and NB4-R2 cells, STMN1 knockdown decreased autonomous cell growth (all p < 0.05) but did not impact ATRA-induced apoptosis and differentiation. Finally, treatment with paclitaxel (as a single agent or combined with ATRA) induced microtubule stabilization, resulting in mitotic catastrophe with repercussions for cell viability, even in ATRA-resistant APL cells. This study provides new insights into the STMN1 functions and microtubule dynamics in APL.


Assuntos
Leucemia Promielocítica Aguda , Diferenciação Celular , Proliferação de Células , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patologia , Mitose , Proteínas de Fusão Oncogênica/genética , Paclitaxel , Estatmina/genética
14.
Ann Hematol ; 101(2): 281-287, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34651249

RESUMO

One of the physiologic mechanisms responsible to maintain asymmetric phospholipid distribution (in particular phosphatidylserine, PS) in human erythrocyte membranes is orchestrated by the balance between enzymes responsible for active transport of PS from the outer to the inner leaflet (ATP11C) and those whose counteracts these activities (PLSCR1). Using quantitative real-time polymerase chain reaction and standard flow cytometry procedures, we hypothesized that the aberrant expression of either or both ATP11C and PLSCR1 transcripts may disrupt the PS internalization/externalization process and become clinically relevant for patients with sickle cell anemia (SCA). Overall, neither ATP11C/PLSCR1 ratio or ATP11C and PLSCR1 (if analyzed separately) had impact on risk to present acute or chronic organ damage in 178 patients with SCA. By collecting a new set of samples from SCA patients during a vaso-occlusive crisis (VOC, crisis state, 13 patients) and comparing with new samples of patients in steady state (15 patients), we noticed that patients in steady state exhibited mean values of ATP11C/PLSCR1 ratio significantly higher (mean value: 18.2, range, 0.3-53) than those who were in crisis (mean value: 3.7, range, 0.5-9) (P = 0.013). Most importantly, there was a strong inverse correlation between PS exposure and ATP11C/PLSCR1 ratio in sickle erythrocytes (Pearson correlation coefficient, r: - 0.78). Based on these findings, it is conceivable that the ATP11C/PLSCR1 ratio may switch from high to low during a VOC, although the underlying reasons require further investigations.


Assuntos
Adenosina Trifosfatases/genética , Anemia Falciforme/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Transferência de Fosfolipídeos/genética , RNA Mensageiro/genética , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transcriptoma , Adulto Jovem
15.
J Immunol ; 204(7): 1859-1868, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122996

RESUMO

Dendritic cells (DCs) participate in the pathogenesis of several diseases. We investigated DCs and the connection between mucosa and joints in a murine model of Yersinia enterocolitica O:3-induced reactive arthritis (ReA) in TNFRp55-/- mice. DCs of mesenteric lymph nodes (MLN) and joint regional lymph nodes (RLN) were analyzed in TNFRp55-/- and wild-type mice. On day 14 after Y. enterocolitica infection (arthritis onset), we found that under TNFRp55 deficiency, migratory (MHChighCD11c+) DCs increased significantly in RLN. Within these RLN, resident (MHCintCD11c+) DCs increased on days 14 and 21. Similar changes in both migratory and resident DCs were also detected on day 14 in MLN of TNFRp55-/- mice. In vitro, LPS-stimulated migratory TNFRp55-/- DCs of MLN increased IL-12/23p40 compared with wild-type mice. In addition, TNFRp55-/- bone marrow-derived DCs in a TNFRp55-/- MLN microenvironment exhibited higher expression of CCR7 after Y. enterocolitica infection. The major intestinal DC subsets (CD103+CD11b-, CD103-CD11b+, and CD103+CD11b+) were found in the RLN of Y. enterocolitica-infected TNFRp55-/- mice. Fingolimod (FTY720) treatment of Y. enterocolitica-infected mice reduced the CD11b- subset of migratory DCs in RLN of TNFRp55-/- mice and significantly suppressed the severity of ReA in these mice. This result was associated with decreased articular IL-12/23p40 and IFN-γ levels. In vitro FTY720 treatment downregulated CCR7 on Y. enterocolitica-infected bone marrow-derived DCs and purified MLN DCs, which may explain the mechanism underlying the impairment of DCs in RLN induced by FTY720. Taken together, data indicate the migration of intestinal DCs to RLN and the contribution of these cells in the immunopathogenesis of ReA, which may provide evidence for controlling this disease.


Assuntos
Artrite Reativa/imunologia , Células Dendríticas/imunologia , Linfonodos/imunologia , Mesentério/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Chamariz do Fator de Necrose Tumoral/metabolismo , Yersiniose/imunologia , Yersinia enterocolitica/imunologia , Animais , Artrite Reativa/metabolismo , Células Dendríticas/metabolismo , Linfonodos/metabolismo , Masculino , Mesentério/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proibitinas , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Transdução de Sinais/imunologia , Receptores Chamariz do Fator de Necrose Tumoral/imunologia , Yersiniose/metabolismo
16.
Crit Care ; 26(1): 206, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35799268

RESUMO

BACKGROUND: The release of neutrophil extracellular traps (NETs) is associated with inflammation, coagulopathy, and organ damage found in severe cases of COVID-19. However, the molecular mechanisms underlying the release of NETs in COVID-19 remain unclear. OBJECTIVES: We aim to investigate the role of the Gasdermin-D (GSDMD) pathway on NETs release and the development of organ damage during COVID-19. METHODS: We performed a single-cell transcriptome analysis in public data of bronchoalveolar lavage. Then, we enrolled 63 hospitalized patients with moderate and severe COVID-19. We analyze in blood and lung tissue samples the expression of GSDMD, presence of NETs, and signaling pathways upstreaming. Furthermore, we analyzed the treatment with disulfiram in a mouse model of SARS-CoV-2 infection. RESULTS: We found that the SARS-CoV-2 virus directly activates the pore-forming protein GSDMD that triggers NET production and organ damage in COVID-19. Single-cell transcriptome analysis revealed that the expression of GSDMD and inflammasome-related genes were increased in COVID-19 patients. High expression of active GSDMD associated with NETs structures was found in the lung tissue of COVID-19 patients. Furthermore, we showed that activation of GSDMD in neutrophils requires active caspase1/4 and live SARS-CoV-2, which infects neutrophils. In a mouse model of SARS-CoV-2 infection, the treatment with disulfiram inhibited NETs release and reduced organ damage. CONCLUSION: These results demonstrated that GSDMD-dependent NETosis plays a critical role in COVID-19 immunopathology and suggests GSDMD as a novel potential target for improving the COVID-19 therapeutic strategy.


Assuntos
Tratamento Farmacológico da COVID-19 , Armadilhas Extracelulares , Animais , Dissulfiram/metabolismo , Armadilhas Extracelulares/metabolismo , Camundongos , Neutrófilos/metabolismo , SARS-CoV-2
17.
Anaerobe ; 77: 102616, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35931287

RESUMO

BACKGROUND: Clostridium chauvoei is a gram-positive, spore-forming, strictly anaerobic bacterium that causes blackleg, a disease that affects cattle by inducing fulminant myonecrosis, thereby leading to high and constant losses of cattle. Macrophages (Mɸs) are depleted in tissues infected with the vegetative form of C. chauvoei, but the mechanism remains partially known. Consequently, Mɸs may be a critical target in the pathogenicity of C. chauvoei. AIM: The objective of this work was to study the mechanism of death of mouse-primary Mɸs infected in vitro for 24 h with the vegetative form of C. chauvoei. METHODS: Mouse peritoneal Mɸs were infected in vitro with different multiplicities of infection (MOIs) of C. chauvoei (i.e., 5:1, 20:1, and 100:1). After 24 h post-infection, cell viability (MTT reduction assay), apoptosis (apoptotic bodies, DNA ladder, and Annexin V assays), and inflammatory cell response (iNOS and TNF-α expression) were assessed. RESULTS: All the MOIs investigated decreased cell viability. An MOI of 20:1 caused the highest production of apoptotic bodies and an electrophoretic DNA-ladder pattern typical of an apoptosis cell death process. These results were corroborated using the Annexin V-flow cytometry assay. Concurrently with apoptotic cell death, Mφs expressed iNOS and TNF-α. CONCLUSION: Inflammation-mediated apoptosis of Mφs can be a potential mechanism of evasion of the immune response used by C. chauvoei in tissues for depleting phagocytic cells at the site of infection.


Assuntos
Doenças dos Bovinos , Infecções por Clostridium , Clostridium chauvoei , Bovinos , Camundongos , Animais , Clostridium chauvoei/genética , Composição de Bases , Fator de Necrose Tumoral alfa , Anexina A5/genética , Doenças dos Bovinos/microbiologia , RNA Ribossômico 16S/genética , Filogenia , Análise de Sequência de DNA , Infecções por Clostridium/microbiologia , Macrófagos , Clostridium/genética
18.
Sensors (Basel) ; 22(9)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35590945

RESUMO

This article presents an Unmanned Underwater Vehicle simulator named Simu2VITA, which was designed to be rapid to set up, easy to use, and simple to modify the vehicle's parameters. Simulation of the vehicle dynamics is divided into three main Modules: the Actuator Module, the Allocation Module and the Dynamics Model. The Actuator Module is responsible for the simulation of actuators such as propellers and fins, the Allocation Module translates the action of the actuators into forces and torques acting on the vehicle and the Dynamics Module implements the dynamics equations of the vehicle. Simu2VITA implements the dynamics of the actuators and of the rigid body of the vehicle using the MATLAB/Simulink® framework. To show the usefulness of the Simu2VITA simulator, simulation results are presented for an unmanned underwater vehicle navigating inside a fully flooded tunnel and then compared with sensor data collected when the real vehicle performed the same mission using the controllers designed employing the simulator.

19.
Rev Med Chil ; 150(2): 147-153, 2022 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-36156639

RESUMO

BACKGROUND: Therapeutic Plasma Exchange (TPE) is a procedure in which plasma and harmful macromolecules are separated from the rest of the blood components by centrifugation or filtration through membranes and are replaced with solutions with albumin and/or plasma. AIM: To communicate our experience using TPE by filtration. MATERIAL AND METHODS: Review of records of 655 TPE sessions performed in 102 patients aged 50 ± 18 years (64% women). The requirement of renal replacement therapy (RRT) and seven days and one year mortality were recorded. RESULTS: Forty five percent of patients had hypertension or diabetes. The main indications for TPE were pulmonary-renal syndrome (PRS) (62%) and antibody mediated graft rejection (29%), followed by neurological diseases (36%). Fifteen percent of patients required RRT for one year. Mortality at seven days and one year was 20 and 30%, respectively. Out of the total of deaths associated with kidney diseases, 88% corresponded to PRS and ANCA vasculitis. The main complications were thrombocytopenia in 41%, hypocalcemia in 18%, and hypotension in 16%. CONCLUSIONS: In our experience, TPE by filtration is a safe technique, with mild and preventable complications. Despite this, the reported mortality is high, which reflects the severity of the diseases that motivated the indication for TPE.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos , Troca Plasmática , Albuminas , Feminino , Glomerulonefrite , Hemorragia , Humanos , Pneumopatias , Masculino , Troca Plasmática/efeitos adversos , Troca Plasmática/métodos , Estudos Retrospectivos
20.
Blood ; 134(12): 951-959, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31292112

RESUMO

By combining the analysis of mutations with aberrant expression of genes previously related to poorer prognosis in both acute promyelocytic leukemia (APL) and acute myeloid leukemia, we arrived at an integrative score in APL (ISAPL) and demonstrated its relationship with clinical outcomes of patients treated with all-trans retinoic acid (ATRA) in combination with anthracycline-based chemotherapy. Based on fms-like tyrosine kinase-3-internal tandem duplication mutational status; the ΔNp73/TAp73 expression ratio; and ID1, BAALC, ERG, and KMT2E gene expression levels, we modeled ISAPL in 159 patients (median ISAPL score, 3; range, 0-10). ISAPL modeling identified 2 distinct groups of patients, with significant differences in early mortality (P < .001), remission (P = .004), overall survival (P < .001), cumulative incidence of relapse (P = .028), disease-free survival (P = .03), and event-free survival (P < .001). These data were internally validated by using a bootstrap resampling procedure. At least for patients treated with ATRA and anthracycline-based chemotherapy, ISAPL modeling may identify those who need to be treated differently to maximize their chances for a cure.


Assuntos
Biomarcadores Tumorais/genética , Análise Mutacional de DNA , Perfilação da Expressão Gênica , Leucemia Promielocítica Aguda/diagnóstico , Leucemia Promielocítica Aguda/genética , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Farmacológicos/análise , Biomarcadores Tumorais/análise , Estudos de Coortes , Análise Mutacional de DNA/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/patologia , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Mutação , Prognóstico , Sequências de Repetição em Tandem/genética , Transcriptoma , Resultado do Tratamento , Tretinoína/administração & dosagem , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/genética
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