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1.
Nature ; 618(7964): 365-373, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225978

RESUMO

Birth presents a metabolic challenge to cardiomyocytes as they reshape fuel preference from glucose to fatty acids for postnatal energy production1,2. This adaptation is triggered in part by post-partum environmental changes3, but the molecules orchestrating cardiomyocyte maturation remain unknown. Here we show that this transition is coordinated by maternally supplied γ-linolenic acid (GLA), an 18:3 omega-6 fatty acid enriched in the maternal milk. GLA binds and activates retinoid X receptors4 (RXRs), ligand-regulated transcription factors that are expressed in cardiomyocytes from embryonic stages. Multifaceted genome-wide analysis revealed that the lack of RXR in embryonic cardiomyocytes caused an aberrant chromatin landscape that prevented the induction of an RXR-dependent gene expression signature controlling mitochondrial fatty acid homeostasis. The ensuing defective metabolic transition featured blunted mitochondrial lipid-derived energy production and enhanced glucose consumption, leading to perinatal cardiac dysfunction and death. Finally, GLA supplementation induced RXR-dependent expression of the mitochondrial fatty acid homeostasis signature in cardiomyocytes, both in vitro and in vivo. Thus, our study identifies the GLA-RXR axis as a key transcriptional regulatory mechanism underlying the maternal control of perinatal cardiac metabolism.


Assuntos
Ácidos Graxos , Glucose , Coração , Leite Humano , Ácido gama-Linolênico , Feminino , Humanos , Recém-Nascido , Gravidez , Cromatina/genética , Ácidos Graxos/metabolismo , Ácido gama-Linolênico/metabolismo , Ácido gama-Linolênico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Coração/efeitos dos fármacos , Coração/embriologia , Coração/crescimento & desenvolvimento , Homeostase , Técnicas In Vitro , Leite Humano/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Receptores X de Retinoides/metabolismo , Fatores de Transcrição/metabolismo
3.
Exp Parasitol ; 187: 49-58, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29496523

RESUMO

Alkylphospholipid analogs were initially developed as anticancer agents and were later found to antiparasitic activity. Miltefosine is the prototype alkylphosphocholine and is the first oral treatment against visceral leishmaniasis. Here we investigated the effects of miltefosine and two ring-substituted alkylphosphocholine derivatives, TCAN26 and TC70, on the viability, morphology, and ultrastructure of the life stages of Caenorhabditis elegans and infective larvae of the parasite Strongyloides venezuelensis. Miltefosine displayed activity against C. elegans adults at low concentrations and was more effective than TCAN26 and TC70. Miltefosine inhibited the hatching of eggs, leading to embryonic lethality, and showed larvicidal activity against C. elegans and S. venezuelensis larvae after 24 h. Mitelfosine also induced alterations in the reproductive system of hermaphrodites, causing vulvar prolapse and general effects in the body wall. Electron microscopy analysis showed that miltefosine induced selective embryonic lethality, leading to cell death. Our results suggest that alkylphospholipid analogs are a potential new alternative for anti-nematode chemotherapy.


Assuntos
Antinematódeos/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Fosfolipídeos/farmacologia , Fosforilcolina/análogos & derivados , Strongyloides/efeitos dos fármacos , Animais , Antinematódeos/química , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/ultraestrutura , Fezes/parasitologia , Larva/efeitos dos fármacos , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Fosfolipídeos/química , Fosforilcolina/química , Fosforilcolina/farmacologia , Ratos , Ratos Wistar , Strongyloides/ultraestrutura
4.
Exp Parasitol ; 167: 43-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27118457

RESUMO

Dinitroanilines are known herbicides that impair the polymerization of microtubules. This study investigated the effects of oryzalin and trifluralin on the viability, morphology, and ultrastructure of different life stages of Caenorhabditis elegans. Both drugs reduced the survival of the adult population in 50% after three days of treatment with concentrations of approximately 30 µM and 57 µM, respectively. The development of new adults was monitored for seven days and treatment with both drugs also showed a decrease in the adult population. 25 µM Oryzalin or trifluralin inhibited the hatching of eggs by nearly 100%. Both drugs showed remarkable larvicidal activity at 25 µM against the larvae at first and second stages (L1-L2) and at third and fourth stages (L3-L4) after 24 h. Treatment with dinitroanilines led to incomplete egg embryo development. The oryzalin and trifluralin treatments caused the detachment of cuticular layers of adults and larvae and the formation of a large number of intracellular membrane whirls and lipid bodies in the hypodermal cells and non-contractile muscles of adults. Both drugs also provoked the bagging process, which generated lesions in the uterus of the adults. In addition, trifluralin caused the detachment of certain areas of the cuticle adjacent to the hypodermis in a large number of nematodes. Our results suggest that dinitroanilines are a potentially new alternative for anthelmintic chemotherapy.


Assuntos
Anti-Helmínticos/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Dinitrobenzenos/farmacologia , Herbicidas/farmacologia , Sulfanilamidas/farmacologia , Trifluralina/farmacologia , Moduladores de Tubulina/farmacologia , Albendazol/farmacologia , Análise de Variância , Animais , Caenorhabditis elegans/anatomia & histologia , Caenorhabditis elegans/ultraestrutura , Larva/efeitos dos fármacos , Larva/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óvulo/efeitos dos fármacos , Óvulo/ultraestrutura
5.
Einstein (Sao Paulo) ; 22: eAO0652, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39140573

RESUMO

OBJECTIVE: To evaluate deaths, hospitalizations, and persistence of symptoms in patients with COVID-19 after infection in an outpatient setting during the first COVID-19 wave in Brazil. METHODS: This prospective cohort was between April 2020 and February 2021. Hospitalized or non-hospitalized COVID-19 patients until five days after symptom onset were included. The outcomes measured were incidence of death, hospitalization, and persistence of more than two symptoms 60 days after discharge. RESULTS: Out of 1,198 patients enrolled in the study, 66.7% were hospitalized. A total of 289 patients died (1 [0.3%] non-hospitalized and 288 [36%] hospitalized). At 60 days, patients non-hospitalized during admission had more persistent symptoms (16.2%) compared to hospitalized (37.1%). The COVID-19 severity variables associated with the persistence of two or more symptoms were increased age (OR= 1.03; p=0.015), respiratory rate at hospital admission (OR= 1.11; p=0.005), length of hospital stay of more than 60 days (OR= 12.24; p=0.026), and need for intensive care unit admission (OR= 2.04; p=0.038). CONCLUSION: COVID-19 survivors who were older, tachypneic at admission, had a hospital length of stay >60 days, and were admitted to the intensive care unit had more persistent symptoms than patients who did not require hospitalization in the early COVID-19 waves.ClinicalTrials.gov Identifier: NCT04479488.


Assuntos
COVID-19 , Hospitalização , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Ambulatorial/estatística & dados numéricos , Brasil/epidemiologia , Estudos de Coortes , COVID-19/mortalidade , COVID-19/epidemiologia , Hospitalização/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Estudos Prospectivos , Índice de Gravidade de Doença
6.
Exp Parasitol ; 135(1): 1-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23727123

RESUMO

This study investigated the effects of albendazole on the viability, morphology and ultrastructure of different life stages of Caenorhabditis elegans. The albendazole EC50 value after seven days of treatment was 18.43 µM. This concentration was very efficient against all the stages. Light and electron microscopy analysis showed damage to the body wall of the adults and larvae. An intense desquamation of the cuticle of larvae and of the surface of the eggs was observed, preventing their hatching and development. The main ultrastructural damage detected was the degeneration of the mitochondria in the noncontractile muscle of the body wall, which appeared as large vacuoles. This study reaffirmed the use of C. elegans as a screening system for compounds with potential anthelmintic activity and showed the effects of albendazole on the different life stages of these worms.


Assuntos
Albendazol/farmacologia , Anti-Helmínticos/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Análise de Variância , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/ultraestrutura , Larva/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
7.
Rev Esc Enferm USP ; 47(5): 1186-93, 2013 Oct.
Artigo em Português | MEDLINE | ID: mdl-24346460

RESUMO

This was a cross-sectional study that aimed to assess the association between work-related stress according to the Demand-Control Model, and the occurrence of Minor Psychic Disorder (MPD) in nursing workers. The participants were 335 professionals, out of which 245 were nursing technicians, aged predominantly between 20 and 40 years. Data were collected using the Job Stress Scale and the Self-Reporting Questionnaire-20. The analysis was performed using descriptive and analytical statistics. The prevalence of suspected MPD was 20.6%. Workers classified in the quadrants active job and high strain of the Demand-Control Model presented higher potential for developing MPD compared with those classified in the quadrant low strain. In conclusion, stress affects the mental health of workers and the aspects related to high psychological demands and high control still require further insight in order to understand their influence on the disease processes of nursing workers.


Assuntos
Esgotamento Profissional/epidemiologia , Modelos Psicológicos , Enfermagem , Doenças Profissionais/epidemiologia , Estresse Psicológico/epidemiologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
8.
Physiol Int ; 110(4): 371-384, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37934202

RESUMO

Background: There are limited data about the influence of stent composition on immune responses after percutaneous coronary intervention (PCI). Objective: The aim was to compare the effects of PCI with conventional cobalt-chromium bare metal stent (BMS) and drug-eluting stent (DES) implantation on the modulation of humoral and cellular immune responses. Methods: A randomised, single-centre, open pilot study involving patients with stable coronary artery disease eligible for PCI was performed. Blood samples were collected from the peripheral artery (PA) and the coronary sinus (CS) at baseline and 40 weeks following PCI. IgM and IgG autoantibodies (Abs), anti-oxLDL and anti-ApoB-D, as well as cytokine levels were evaluated by enzyme-linked immunosorbent assay. Results: A total of 30 patients of 60 years mean age were included, 68% of whom were men. At the nine-month follow-up, a modulation in the levels of cytokines and autoantibodies was observed in both stent type groups. However, no difference was observed in the modulation of these markers between stents. Conclusion: The stent type promotes modulations in cellular and humoral immune responses in the long-term, with differences in the magnitude of effects in specific immune responses.


Assuntos
Angioplastia Coronária com Balão , Stents Farmacológicos , Intervenção Coronária Percutânea , Feminino , Humanos , Masculino , Autoanticorpos , Imunidade , Metais , Projetos Piloto , Fatores de Risco , Stents , Resultado do Tratamento , Pessoa de Meia-Idade
9.
Atheroscler Plus ; 48: 27-36, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36644561

RESUMO

Background and aims: Familial hypercholesterolemia (FH) is characterized by lifelong exposure to high LDL-c concentrations and premature atherosclerotic cardiovascular disease; nevertheless, disease severity can be heterogeneous.We aimed at evaluating if the immune-inflammatory system could modulate atherosclerosis burden in FH. Methods: From a cohort of subjects with confirmed FH (Dutch Lipid Clinic Network and genotype), 92 patients receiving high-intensity lipid-lowering therapy (statin ± ezetimibe) were included. The extension and severity of coronary atherosclerosis was assessed by standardized reporting systems (CAD-RADS) for coronary computed tomography angiography (CCTA) and coronary artery calcium (CAC) scores. Lipids, apolipoproteins, anti-oxLDL and anti-apolipoprotein B-D peptide (anti-ApoB-D) autoantibodies (IgM and IgG), lymphocytes subtypes, platelet, monocyte and endothelial microparticles (MP), IgM levels (circulating or produced by B1 cells) and cytokines in the supernatant of cultured cells were determined. Multiple linear regression models evaluated associations of these biomarkers with CAC and CAD-RADS scores. Results: In univariate analysis CAC correlated with age, systolic blood pressure, TCD4+ cells, and titers of IgM anti-ApoB-D. In multiple linear regression [ANOVA F = 2.976; p = 0.024; R2 = 0.082), CD4+T lymphocytes (B = 35.289; beta = 0.277; p = 0.010; 95%CI for B 8.727 to 61.851), was independently associated with CAC. CAD-RADS correlated with age, systolic blood pressure, titers of IgM anti-ApoB-D, and endothelial MP in univariate analysis. In multiple linear regression, [ANOVA F = 2.790; p = 0.032; R2 = 0.119), only age (B = 0.027; beta = 0.234; p = 0.049; 95% CI for B 0.000 to 0.053) was independent predictor. Conclusions: In subjects with FH, under high-intensity lipid-lowering therapy, age and CD4+T cells were associated to atherosclerosis burden.

10.
Arq Bras Cardiol ; 116(4): 844-849, 2021 04.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33886738

RESUMO

BACKGORUND: Traditional and HIV-defined risk factors may be associated with an increase in cardiovascular events. Recent studies have suggested that the humoral immune response to modified LDL may be associated with the process of atherosclerosis. OBJECTIVES: To evaluate the presence of anti-oxLDL and apolipoprotein B-derived peptides in the blood, and their association with the endothelial function in HIV-infection. METHODS: This study consecutively included subjects matched for age, gender, and demographic data in two groups: (1) HIV-infected and naïve for antiviral therapy and (2) uninfected individuals. Subclinical atherosclerosis was assessed by intimal-media thickness, using ultrasonography of the carotid arteries. Endothelial function was determined by flow-mediated dilatation (FMD) of the brachial artery by ultrasonography. Autoantibodies (IgM, IgG) anti-oxidized low-density lipoprotein (oxLDL), anti-apolipoprotein B-peptide fragments (ApoB-D and 0033G-Cys peptides), and cytokine levels were evaluated by ELISA. RESULTS: This study's results showed no difference in subclinical atherosclerosis between groups; however, HIV-infected subjects showed a lower FMD, when compared to non-infected subjects. Therefore, HIV-infected subjects showed higher levels of inflammatory cytokines, titers of IgG anti-oxLDL, and IgG anti-ApoB-D. In contrast, titers of IgM anti-ApoB-D were lower in HIV-infected individuals and associated with reduced endothelial functions. CONCLUSIONS: This study's results show that HIV infection, in naïve subjects, is associated with endothelial dysfunction and a decline of natural antibodies to apo-B antigens.


FUNDAMENTO: Fatores de risco definidos para HIV e tradicionais podem estar associados a um aumento de eventos cardiovasculares. Estudos recentes sugerem que a resposta imune humoral à LDL modificada pode estar associada ao processo de aterosclerose. OBJETIVOS: Avaliar a presença de anti-LDL oxidada e de peptídeos derivados da Apolipoproteína B no sangue, bem como sua associação à função endotelial na infecção por HIV. MÉTODOS: Este estudo incluiu consecutivamente sujeitos com idade, sexo e dados demográficos correspondentes em dois grupos: (1) indivíduos infectados com HIV e naïve para terapia antiviral e (2) indivíduos não infectados. A aterosclerose subclínica foi avaliada pela espessura íntima-média, utilizando-se a ultrassonografia das artérias carótidas. A função endotelial foi determinada pela dilatação mediada por fluxo (DMF) da artéria braquial por ultrassonografia. Os níveis de autoanticorpos (IgM, IgG) de lipoproteínas de baixa densidade antioxidadas (LDL-ox), fragmentos de peptídeos antiapolipoproteína B (peptídeos ApoB-D e 0033G-Cys), e citocina foram avaliados por meio de ELISA. RESULTADOS: Os resultados deste estudo não mostraram diferenças na aterosclerose subclínica entre os grupos. Entretanto, os sujeitos infectados com HIV apresentaram uma DMF mais baixa, em comparação com os sujeitos não infectados. Portanto, os sujeitos infectados com HIV apresentaram níveis mais altos de citocinas inflamatórias, títulos de IgG anti-LDL-ox, e IgG anti-ApoB-D. Em contraste, títulos de IgM anti-ApoB-D foram mais baixos em indivíduos infectados com HIV e associados a funções endoteliais diminuídas. CONCLUSÕES: Os resultados deste estudo mostram que a infecção por HIV, em sujeitos naïve, está associada à disfunção endotelial e à diminuição de anticorpos naturais para antígenos Apo-B.


Assuntos
Autoantígenos , Infecções por HIV , Apolipoproteínas B , Humanos , Imunoglobulina G , Imunoglobulina M , Lipoproteínas LDL
11.
J Med Microbiol ; 69(4): 576-586, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32125264

RESUMO

Introduction. In some species, the population structure of pathogenic bacteria is clonal. However, the mechanisms that determine the predominance and persistence of specific bacterial lineages of group C Streptococcus remain poorly understood. In Brazil, a previous study revealed the predominance of two main lineages of Streptococcus dysgalactiae subsp. equisimilis (SDSE).Aim. The aim of this study was to assess the virulence and fitness advantages that might explain the predominance of these SDSE lineages for a long period of time.Methodology. emm typing was determined by DNA sequencing. Adhesion and invasion tests were performed using human bronchial epithelial cells (16HBE14o-). Biofilm formation was tested on glass surfaces and the presence of virulence genes was assessed by PCR. Additionally, virulence was studied using Caenorhabditis elegans models and competitive fitness was analysed in murine models.Results. The predominant lineages A and B were mostly typed as emm stC839 and stC6979, respectively. Notably, these lineages exhibited a superior ability to adhere and invade airway cells. Furthermore, the dominant lineages were more prone to induce aversive olfactory learning and more likely to kill C. elegans. In the competitive fitness assays, they also showed increased adaptability. Consistent with the increased virulence observed in the ex vivo and in vivo models, the predominant lineages A and B showed a higher number of virulence-associated genes and a superior ability to accumulate biofilm.Conclusion. These results suggest strongly that this predominance did not occur randomly but rather was due to adaptive mechanisms that culminated in increased colonization and other bacterial properties that might confer increased bacteria-host adaptability to cause disease.


Assuntos
Biodiversidade , Infecções Estreptocócicas/microbiologia , Streptococcus/patogenicidade , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Brasil , Caenorhabditis elegans , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Streptococcus/classificação , Streptococcus/genética , Streptococcus/isolamento & purificação , Virulência
13.
Bio Protoc ; 7(2): e2113, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34458440

RESUMO

This protocol proposes to use the nematode Caenorhabditis elegans as a model to screen and study the anthelmintic activity of natural and synthetic compounds and to observe their effects on the morphology and the ultrastructure of the helminths. Furthermore, C. elegans can be used to investigate the anthelmintic activity in embryonated eggs, larval stages and in the adults' survival. As most current anthelmintics are not effective against all nematode life stages, this protocol can contribute to the identification of new alternatives to helminthic infections (Sant' Anna et al., 2016 ).

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