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La osteoartritis (OA) de la articulación temporomandibular (ATM) es un desorden degenerativo de etiología multifactorial, que requiere un manejo interdisciplinario. Es considerada como la enfermedad degenerativa más frecuente de la articulación. Por esto es importante conocer lo más preciso posible las estructuras internas del área donde se requiere realizar la intervención o tratamiento, en este caso la ATM. Para esto existen distintos exámenes radiográficos complementarios como: tomografía computarizada, resonancia magnética y por último la tomografía computarizada de haz cónico (CBCT), debido a su capacidad de visualizar tridimensionalmente y con buena definición las estructuras óseas y distintas patologías o alteraciones presentes. A pesar de esto, no hay suficiente evidencia actual que demuestre la frecuencia de signos óseos de osteoartritis presentes en ATM según edad y sexo en la población Chilena. El objetivo este trabajo consistió en Determinar frecuencia de los signos óseos en osteoartritis de ATM mediante CBCT en una población adulta Chilena atendida en un centro radiológico durante los años 2021-2022. Se realizó un estudio observacional descriptivo, donde se observó informes radiológicos de CBCT en pacientes adultos atendidos en el centro radiológico privado de Valdivia durante el periodo del primer semestre del 2021 a primer semestre 2022. Se evaluó la presencia de los siguientes signos óseos imagenológicos: aplanamiento de superficie articular, erosión superficial, osteofitos condilares, esclerosis subcondral, quistes subcortical, esclerosis generalizada, cuerpos libres intraarticulares, reabsorción completa y parcial de la cabeza condilar y trabeculado heterogéneo. De un total de 101 exámenes, 70 exámenes fueron considerados válidos para este estudio según los criterios de selección. Los 31 exámenes restantes no calificaron según los criterios o no presentaban osteoartritis de ATM. De los 70 pacientes 58 pertenecían a mujeres y 12 a hombres. El promedio de edad fue de 37,2 años. Los signos imagenológicos más frecuentes fueron: Trabeculado heterogéneo, Aplanamiento de la superficie articular, Esclerosis subcondral condilar.
Osteoarthritis (OA) of the temporomandibular joint (TMJ) is a degenerative disorder of multifactorial etiology, requiring interdisciplinary management. It is considered the most common degenerative joint disease. For this reason, it is important to know asprecisely as possible the internal structures of the area where the intervention or treatment is required, in this case the TMJ. For this purpose, there are several additional radiographic examinations such as: computed tomography, magnetic resonance imaging and finally cone-beam computed tomography (CBCT), due to its ability to visualize three-dimensionally and with good definition the bone structures and different pathologies or present alterations. Despite this, there is not enough current evidence to demonstrate the frequency of osteoarthritis bone signs present in TMJ according to age and gender in the Chilean population. The aim of this study was to determine the frequency of bone signs of TMJ osteoarthritis through CBCT in a Chilean adult population attended in a radiological center during 2021-2022. A descriptive observational study was made, where CBCT radiological reports were observed in adult patients attended in a private radiological center in Valdivia during the first semester of 2021 to the first semester of 2022. The presence of the following imaging bone signs was evaluated: flattening of the articular surface, surface erosion, condylar osteophytes, subchondral sclerosis, subcortical cysts, generalized sclerosis, intraarticular free bodies, complete and partial reabsorption of the condylar head and heterogeneous trabeculate. Of a total of 101 examinations, 70 examinations were considered valid for this study according to the selection criteria. The remaining 31 examinations did not qualify according to the criteria or did not present TMJ osteoarthritis. Of the 70 patients, 58 were female and 12 were male. The average age was 37.2 years. The most frequent imaging signs were: heterogeneous trabeculation, flattening of the articular surface, subchondral condylar sclerosis.
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Chagas disease, also known as American trypanosomiasis, is a neglected tropical disease caused by the protozoa Trypanosoma cruzi, affecting nearly 7 million people only in the Americas. Polyamines are essential compounds for parasite growth, survival, and differentiation. However, because trypanosomatids are auxotrophic for polyamines, they must be obtained from the host by specific transporters. In this investigation, an ensemble of QSAR classifiers able to identify polyamine analogs with trypanocidal activity was developed. Then, a multi-template homology model of the dimeric polyamine transporter of T. cruzi, TcPAT12, was created with Rosetta, and then refined by enhanced sampling molecular dynamics simulations. Using representative snapshots extracted from the trajectory, a docking model able to discriminate between active and inactive compounds was developed and validated. Both models were applied in a parallel virtual screening campaign to repurpose known drugs as anti-trypanosomal compounds inhibiting polyamine transport in T. cruzi. Montelukast, Quinestrol, Danazol, and Dutasteride were selected for in vitro testing, and all of them inhibited putrescine uptake in biochemical assays, confirming the predictive ability of the computational models. Furthermore, all the confirmed hits proved to inhibit epimastigote proliferation, and Quinestrol and Danazol were able to inhibit, in the low micromolar range, the viability of trypomastigotes and the intracellular growth of amastigotes.
Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Humanos , Putrescina/uso terapêutico , Ligantes , Danazol/uso terapêutico , Quinestrol/uso terapêutico , Poliaminas/química , Poliaminas/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Proteínas de Membrana Transportadoras/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/químicaRESUMO
In the pathogen Typanosoma cruzi, the calcium ion (Ca2+) regulates key processes for parasite survival. However, the mechanisms decoding Ca2+ signals are not fully identified or understood. Here, we investigate the role of a hypothetical Ca2+-binding protein named TcCAL1 in the in vitro life cycle of T. cruzi. Results showed that the overexpression of TcCAL1 fused to a 6X histidine tag (TcCAL1-6xHis) impaired the differentiation of epimastigotes into metacyclic trypomastigotes, significantly decreasing metacyclogenesis rates. When the virulence of transgenic metacyclic trypomastigotes was explored in mammalian cell invasion assays, we found that the percentage of infection was significantly higher in Vero cells incubated with TcCAL1-6xHis-overexpressing parasites than in controls, as well as the number of intracellular amastigotes. Additionally, the percentage of Vero cells with adhered metacyclic trypomastigotes significantly increased in samples incubated with TcCAL1-6xHis-overexpressing parasites compared with controls. In contrast, the differentiation rates from metacyclic trypomastigotes to axenic amastigotes or the epimastigote proliferation in the exponential phase of growth have not been affected by TcCAL1-6xHis overexpression. Based on our findings, we speculate that TcCAL1 exerts its function by sequestering intracellular Ca2+ by its EF-hand motifs (impairing metacyclogenesis) and/or due to an unknown activity which could be amplified by the ion binding (promoting cell invasion). This work underpins the importance of studying the kinetoplastid-specific proteins with unknown functions in pathogen parasites.
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Doença de Chagas , Trypanosoma cruzi , Animais , Chlorocebus aethiops , Estágios do Ciclo de Vida , Mamíferos/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Células VeroRESUMO
Background: Chagas disease is a lifelong infection caused by the protozoa Trypanosoma cruzi endemic in Latin-America and emergent worldwide. Decades after primary infection, 20-30% of infected people develop chronic Chagas cardiomyopathy (CCC) while the others remain asymptomatic. CCC pathogenesis is complex but associated with sustained pro-inflammatory response leading to tissue damage. Hence, levels of IL-10 could have a determinant role in CCC etiology. Studies with Latin-American populations have addressed the association of genetic variants of IL-10 and the risk of developing CCC with inconsistent results. We carried out a case control study to explore the association between IL-10-1082G>A (rs18008969), -819C>T (rs1800871), -592A>C (rs1800872) polymorphisms and CCC in a population attending a hospital in Buenos Aires Argentina. Next, a systematic review of the literature and a meta-analysis were conducted combining present and previous studies to further study this association. Methods: Our case control study included 122 individuals with chronic T. cruzi infection including 64 patients with any degree of CCC and 58 asymptomatic individuals. Genotyping of IL-10 -1082G>A, -819C>T, -592A>C polymorphisms was performed by capillary sequencing of the region spanning the three polymorphic sites and univariate and multivariate statistical analysis was undertaken. Databases in English, Spanish and Portuguese language were searched for papers related to these polymorphisms and Chagas disease up to December 2021. A metanalysis of the selected literature and our study was performed based on the random effect model. Results: In our cohort, we found a significant association between TT genotype of -819 rs1800871 and AA genotype of -592 rs1800872 with CCC under the codominant (OR=5.00; 95%CI=1.12-23.87 P=0,04) and the recessive models (OR=5.37; 95%CI=1.12-25.68; P=0,03). Of the genotypes conformed by the three polymorphic positions, the homozygous genotype ATA was significantly associated with increased risk of CCC. The results of the meta-analysis of 754 cases and 385 controls showed that the TT genotype of -819C>T was associated with increased CCC risk according to the dominant model (OR=1.13; 95% CI=1.02-1.25; P=0,03). Conclusion: The genotype TT at -819 rs1800871 contributes to the genetic susceptibility to CCC making this polymorphism a suitable candidate to be included in a panel of predictive biomarkers of disease progression.
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Cardiomiopatia Chagásica , Doença de Chagas , Estudos de Casos e Controles , Cardiomiopatia Chagásica/genética , Doença de Chagas/genética , Humanos , Interleucina-10/genética , Fatores de RiscoRESUMO
Current challenges in froth flotation are the presence of complex gangues and the use of low-quality waters, such as seawater. In this scenario, the recovery of molybdenum minerals is difficult, mainly due to the hydrophobic faces' physicochemical changes. In the present study, the natural floatability of pure molybdenite was analyzed by using microflotation assays, and hydrophobicity was measured by performing contact-angle measurements. The impact of two clays, kaolin (non-swelling) and Na-montmorillonite (swelling), was studied. The behavior in freshwater and seawater at pH 8 was compared, considering the current condition of the Cu/Mo mining industries, which use seawater in their operations. The presence of clays lowered the natural floatability of molybdenite precisely because they adhere to the surface and reduce its contact angle. However, the intensity with which they cause this phenomenon depends on the type of water and clay. Kaolin strongly adheres to the valuable mineral in both freshwater and seawater. For its part, Na-montmorillonite does it with greater intensity in a saline medium, but in freshwater, a high concentration of phyllosilicate is required to reduce the hydrophobicity of molybdenite. The clays' adherence was validated by scanning electron microscopy (SEM) analysis.
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The manufacture of pharmaceutical products made under good manufacturing practices (GMP) must comply with the guidelines of national regulatory bodies based on international or regional compendia. The existence of this type of regulation allows pharmaceutical laboratories to count on the standardization of high-quality production processes, obtaining a safe product for human use, with a positive impact on public health. In addition, the COVID-19 pandemic highlights the importance of having more and better-distributed manufacturing plants, emphasizing regions such as Latin America. This review shows the most important GMP standards in the world and, in particular, their relevance in the production of vaccines and antibodies.
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COVID-19 , Vacinas , Humanos , Indústria Farmacêutica , Pandemias , COVID-19/prevenção & controle , Padrões de ReferênciaRESUMO
Hemolytic Uremic Syndrome (HUS), a disease triggered by Shiga toxin (Stx), is characterized by hemolytic anemia, thrombocytopenia and renal failure. The inflammatory response mediated by polymorphonuclear neutrophils (PMNs) and monocytes is essential to HUS onset. Still, the role of anti-inflammatory cytokines is less clear. The deficiency of IL-10, an anti-inflammatory cytokine, leads to severe pathology in bacterial infections but also to beneficial effects in models of sterile injury. The aim of this work was to analyze the role of IL-10 during HUS. Control and IL-10 lacking mice (IL-10-/-) were intravenously injected with Stx type 2 (Stx2) and survival rate was evaluated. PMN and circulating and renal pro- and anti-inflammatory factors were analyzed by FACS and enzyme-linked immunosorbent assay (ELISA) respectively. IL-10-/- mice showed a higher survival associated with lower renal damage reflected by reduced plasma urea and creatinine levels than control mice. Circulating PMN increased at 72 h in both mouse strains accompanied by an up-regulation of CD11b in control mice. In parallel, renal PMN were significantly increased only in control mice after toxin. Plasma TNF-α, IL-6 and corticosterone levels were higher increased in IL-10-/- than control mice. Simultaneously renal TNF-α raised constantly but was accompanied by increased TGF-ß levels in IL-10-/- mice. These results demonstrate that the profile of circulating and renal cytokines after Stx2 differed between strains suggesting that balance of these factors could participate in renal protection. We conclude that IL-10 absence has a protective role in an experimental model of HUS by reducing PMN recruitment into kidney and renal damage, and increasing mice survival.
Assuntos
Síndrome Hemolítico-Urêmica/induzido quimicamente , Interleucina-10/metabolismo , Toxina Shiga II/toxicidade , Animais , Corticosterona/sangue , Síndrome Hemolítico-Urêmica/patologia , Interleucina-10/genética , Interleucina-6/sangue , Rim/química , Rim/patologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Neutrófilos , Taxa de Sobrevida , Fator de Crescimento Transformador beta , Fator de Necrose Tumoral alfa/sangueRESUMO
Introducción. La infección por SARS-CoV2 genera una morbimortalidad importante, por lo cual es necesario conocer el estado funcional post infección de los pacientes con el fin de desarrollar intervenciones en rehabilitación adecuadas. Objetivo. Definir el compromiso osteomuscular, funcional y de equilibrio en un grupo de pacientes recuperados de COVID-19 y atendidos en un hospital universitario de cuarto nivel de Cali, Colombia. Materiales y métodos. Estudio descriptivo de corte transversal en el cual se realizaron mediciones funcionales en pacientes recuperados de COVID-19, los cuales se clasificaron en dos grupos: con ingreso o sin ingresó a la unidad de cuidados intensivos (UCI). Resultados. En los pacientes con ingreso a UCI se encontró mayor número de comorbilidades y un mayor impacto funcional en escalas como la FIM, en especial el componente motor. Conclusión. Dados los resultados, es de gran importancia hacerles un buen seguimiento a los pacientes sobrevivientes de COVID-19 para en el futuro diseñar planes específicos para su rehabilitación.
Introduction. SARS-CoV2 infection generates an important morbimortality, so it is necessary to know the post-infection functional status of patients in order to develop appropriate rehabilitation interventions. Objective. To define the musculoskeletal, functional and balance compromise in a group of patients recovered from COVID-19 and treated in a fourth level university hospital in Cali, Colombia. Materials and methods. Descriptive cross-sectional study in which functional measurements were taken in patients recovered from COVID-19, who were classified into two groups: with or without admission to the intensive care unit (ICU). Results. Patients admitted to the ICU had a greater number of comorbidities and a greater functional impact on scales such as the FIM, especially the motor component. Conclusion. Given the results, it is of great importance to follow up COVID-19 survivors in order to design specific plans for their rehabilitation in the future.
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Humanos , Masculino , FemininoRESUMO
IL-10 is an anti-inflammatory cytokine that plays a significant role in the modulation of the immune response in many pathological conditions, including infectious diseases. Infection with Trypanosoma cruzi (T. cruzi), the etiological agent of Chagas disease, results in an ongoing inflammatory response that may cause heart dysfunction, ultimately leading to heart failure. Given its infectious and inflammatory nature, in this work we analyzed whether the lack of IL-10 hinders the anti-inflammatory effects of fenofibrate, a PPARα ligand, in a murine model of Chagas heart disease (CHD) using IL-10 knockout (IL-10 KO) mice. Our results show fenofibrate was able to restore the abnormal cardiac function displayed by T. cruzi-infected mice lacking IL-10. Treatment with fenofibrate reduced creatine kinase (CK) levels in sera of IL-10 KO mice infected with T. cruzi. Moreover, although fenofibrate could not modulate the inflammatory infiltrates developing in the heart, it was able to reduce the increased collagen deposition in infected IL-10 KO mice. Regarding pro-inflammatory mediators, the most significant finding was the increase in serum IL-17. These were reduced in IL-10 KO mice upon fenofibrate treatment. In agreement with this, the expression of RORγt was reduced. Infection of IL-10 KO mice increased the expression of YmI, FIZZ and Mannose Receptor (tissue healing markers) that remained unchanged upon treatment with fenofibrate. In conclusion, our work emphasizes the role of anti-inflammatory mechanisms to ameliorate heart function in CHD and shows, for the first time, that fenofibrate attains this through IL-10-dependent and -independent mechanisms.
Assuntos
Cardiomiopatia Chagásica/tratamento farmacológico , Fenofibrato/uso terapêutico , Hipolipemiantes/uso terapêutico , Interleucina-10/metabolismo , Miocárdio/patologia , Trypanosoma cruzi/fisiologia , Tripanossomíase/tratamento farmacológico , Animais , Células Cultivadas , Cardiomiopatia Chagásica/imunologia , Creatina Quinase/sangue , Modelos Animais de Doenças , Humanos , Interleucina-10/genética , Interleucina-17/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Tripanossomíase/imunologia , CicatrizaçãoRESUMO
Trypanosoma cruzi carbonic anhydrase (TcCA) has recently emerged as an interesting target for the design of new compounds to treat Chagas disease. In this study we report the results of a structure-based virtual screening campaign to identify novel and selective TcCA inhibitors. The combination of properly validated computational methodologies such as comparative modelling, molecular dynamics and docking simulations allowed us to find high potency hits, with KI values in the nanomolar range. The compounds also showed trypanocidal effects against T. cruzi epimastigotes and trypomastigotes. All the candidates are selective for inhibiting TcCA over the human isoform CA II, which is encouraging in terms of possible therapeutic safety and efficacy.
Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Doença de Chagas/tratamento farmacológico , Ciclamatos/farmacologia , Tripanossomicidas/farmacologia , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Doença de Chagas/metabolismo , Ciclamatos/síntese química , Ciclamatos/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Humanos , Modelos Moleculares , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/química , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/enzimologiaRESUMO
La mamoplastia de aumento con implantes y la reconstrucción mamaria posmastectomía son algunos de los procedimientos quirúrgicos más frecuentes en cirugía plástica. Los implantes mamarios se encuentran entre los dispositivos médicos con mayor cantidad de informes por eventos adversos en el país. La extracción del implante es el estándar de oro ante la sospecha de la ruptura del mismo; sin embargo, hay poca claridad respecto a qué estrategias e imágenes son las adecuadas para la evaluación no invasiva de estos. La ecografía de alta resolución ha mostrado ser una alternativa para la evaluación inicial. Debido a la variabilidad de los implantes es necesario reconocer sus características imagenológicas. En este artículo se presentan los hallazgos ecográficos de los implantes, incluyendo aquellos que se pueden generar por marquillas o distintivos propios de la marca, y los propios de las complicaciones más comunes asociadas a ellos.
Implant augmentation mammoplasty and post-mastectomy breast reconstruction are some of the most frequent surgical procedures in plastic surgery. Breast implants are among the medical devices with the highest amount of reports of adverse events in our country. In suspicion of rupture, removal is the gold standard. However, there is little clarity regarding which strategies and images are adequate for non-invasive evaluation. High resolution ultrasound has shown to be an alternative for the initial evaluation. Due to the variability of the implants it is necessary to recognize their imaging characteristics. This article presents the findings of the ultrasound of the implants, including those that can be generated by tags or marks distinctive of the brand and those of the most common complications associated with them
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Implantes de Mama , Ruptura/diagnóstico por imagem , Ultrassonografia Mamária , Achados Incidentais , GângliosAssuntos
Erradicação de Doenças , Malária/prevenção & controle , Animais , Anopheles/parasitologia , Argentina/epidemiologia , Controle de Doenças Transmissíveis/economia , Controle de Doenças Transmissíveis/história , Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Importadas/história , Doenças Transmissíveis Importadas/prevenção & controle , Doenças Transmissíveis Importadas/transmissão , Erradicação de Doenças/história , Doenças Endêmicas , Política de Saúde , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Mordeduras e Picadas de Insetos/parasitologia , Insetos Vetores/parasitologia , Malária/epidemiologia , Malária/história , Malária/transmissão , Controle de Mosquitos/economia , Controle de Mosquitos/história , Controle de Mosquitos/métodosAssuntos
Doença de Chagas/tratamento farmacológico , Clofazimina/uso terapêutico , Di-Hidropiridinas/uso terapêutico , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêutico , Animais , Doença de Chagas/patologia , Chlorocebus aethiops , Doença Crônica , Clofazimina/química , Terapia Combinada , Di-Hidropiridinas/química , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C3H , Nitroimidazóis/química , Tripanossomicidas/química , Células VeroRESUMO
Anti-parasitic treatment for Chagas disease mainly relies on benznidazole, which is virtually the only drug available in the market. Besides its anti-parasitic effects, benznidazole has anti-inflammatory properties. In this work we studied the mechanisms involved in the latter, demonstrating the participation of the IL-10/STAT3/SOCS3 pathway. To achieve this goal, the anti-inflammatory properties of benznidazole were studied using an in vitro model of cardiomyocyte primary culture stimulated with LPS. LPS increased both SOCS3 expression and STAT3 phosphorylation. The addition of benznidazole increased their expression even further. Specific inhibition of STAT3 precluded this effect, suggesting a role for STAT3 in the increase of SOCS3 expression induced by benznidazole. To assess the participation of SOCS3 in the anti-inflammatory effect of benznidazole, we accomplished specific knockdown of SOCS3 with siRNA. Silencing of SOCS3 in cardiomyocytes precluded the inhibitory effects of benznidazole on TNF-α, IL-6, iNOS expression and NO release. Moreover, in the absence of SOCS3, benznidazole could neither prevent IKK phosphorylation nor IκBα degradation, supporting the notion that SOCS3 is required for the benznidazole-mediated inhibition of the NF-κB pathway. Previously, we demonstrated that IL-10 increases the expression of SOCS3 in cultured cardiomyocytes. Here, we found that benznidazole shows a trend to increased IL-10 expression. To evaluate whether benznidazole increased SOCS3 in an IL-10-dependent manner, cardiomyocytes from IL-10 knockout mice were pre-treated with benznidazole and stimulated with LPS. Benznidazole neither inhibited NO release nor avoid IKK phosphorylation or IκBα degradation, showing that IL-10 is required for benznidazole-mediated inhibition of NF-κB. Moreover, exogenous addition of IL-10 to IL-10 knockout cardiomyocytes restored the inhibitory effect of benznidazole on NO release. The results reported herein show, for the first time, that the IL-10/STAT3/SOCS3 axis is involved in the anti-inflammatory effects of benznidazole. These findings may add up to new therapeutic strategies for chronic Chagas disease given its inflammatory nature.
Assuntos
Anti-Inflamatórios/farmacologia , Interleucina-10/metabolismo , Nitroimidazóis/farmacologia , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Animais , Anti-Inflamatórios/química , Biomarcadores , Células Cultivadas , Citocinas/metabolismo , Regulação da Expressão Gênica , Mediadores da Inflamação/metabolismo , Interleucina-10/genética , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Knockout , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Nitroimidazóis/química , Proteína 3 Supressora da Sinalização de Citocinas/genéticaRESUMO
IL-10 is a pleiotropic cytokine with immunoregulatory functions affecting various cell types. In a model of experimental infection with the protozoan Trypanosoma cruzi (T. cruzi), we found increased morbidity and lower parasite control in IL-10 deficient mice (IL-10 KO) compared to wild-type (WT) mice. Despite enhanced MÏ function and dendritic cell activation, IL-10 KO mice were more susceptible to infection. The kinetics of T cells in spleen and peripheral blood revealed that infected IL-10 KO mice failed to increase the number of spleen and circulating total CD8+ T cells, a phenomenon observed from the second week of infection in WT mice. Total CD8+ T cells from IL-10 KO mice exhibited diminished proliferation, cytotoxic potential and IFN-γ production than their WT counterparts and T. cruzi-specific CD8+ T cells displayed reduced in vivo cytotoxicity. The absence of IL-10 selectively affected expansion, survival, and increased PD-1 expression of CD8+ T cells without altering these same parameters on CD4+ T cells. Increased inhibitory receptors expression and down-modulation of T-bet by CD8+ T cells from IL-10 KO infected mice were compatible with a T cell exhaustion phenotype. Collectively, these findings reveal that during acute infection, IL-10 plays a previously unrecognized stimulatory role on CD8+ T cells, the most relevant lymphocyte population for the control of intracellular T. cruzi stages. A clear knowledge of the underlying mechanisms that drive effector functions of cytotoxic T cells is critical to understand pathogen persistence and rational design of prophylactic strategies against T. cruzi.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Interleucina-10/metabolismo , Ativação Linfocitária/imunologia , Trypanosoma cruzi/patogenicidade , Doença Aguda , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Interleucina-2/biossíntese , Ativação Linfocitária/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fenótipo , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Interleucina-10/metabolismo , Proteínas Recombinantes/farmacologia , Baço/patologia , VirulênciaRESUMO
Chagas disease is a neglected tropical disease endemic to Latin America, though migratory movements have recently spread it to other regions. Here, we have applied a cascade virtual screening campaign combining ligand- and structure-based methods. In order to find novel inhibitors of putrescine uptake in Trypanosoma cruzi, an ensemble of linear ligand-based classifiers obtained by has been applied as initial screening filter, followed by docking into a homology model of the putrescine permease TcPAT12. 1,000 individual linear classifiers were inferred from a balanced dataset. Subsequently, different schemes were tested to combine the individual classifiers: MIN operator, average ranking, average score, average voting, with MIN operator leading to the best performance. The homology model was based on the arginine/agmatine antiporter (AdiC) from Escherichia coli as template. It showed 64% coverage of the entire query sequence and it was selected based on the normalized Discrete Optimized Protein Energy parameter and the GA341 score. The modeled structure had 96% in the allowed area of Ramachandran's plot, and none of the residues located in non-allowed regions were involved in the active site of the transporter. Positivity Predictive Value surfaces were applied to optimize the score thresholds to be used in the ligand-based virtual screening step: for that purpose Positivity Predictive Value was charted as a function of putative yields of active in the range 0.001-0.010 and the Se/Sp ratio. With a focus on drug repositioning opportunities, DrugBank and Sweetlead databases were subjected to screening. Among 8 hits, cinnarizine, a drug frequently prescribed for motion sickness and balance disorder, was tested against T. cruzi epimastigotes and amastigotes, confirming its trypanocidal effects and its inhibitory effects on putrescine uptake. Furthermore, clofazimine, an antibiotic with already proven trypanocidal effects, also displayed inhibitory effects on putrescine uptake. Two other hits, meclizine and butoconazole, also displayed trypanocidal effects (in the case of meclizine, against both epimastigotes and amastigotes), without inhibiting putrescine uptake.
Assuntos
Transporte Biológico/efeitos dos fármacos , Putrescina/metabolismo , Tripanossomicidas/antagonistas & inibidores , Tripanossomicidas/química , Tripanossomicidas/isolamento & purificação , Doença de Chagas/dietoterapia , Cinarizina/antagonistas & inibidores , Clofazimina/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos/métodos , Reposicionamento de Medicamentos , Imidazóis/antagonistas & inibidores , Meclizina/antagonistas & inibidores , Proteínas de Membrana Transportadoras , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/metabolismoRESUMO
TcTASV-C is a protein family of about 15 members that is expressed only in the trypomastigote stage of Trypanosoma cruzi. We have previously shown that TcTASV-C is located at the parasite surface and secreted to the medium. Here we report that the expression of different TcTASV-C genes occurs simultaneously at the trypomastigote stage and while some secreted and parasite-associated products are found in both fractions, others are different. Secreted TcTASV-C are mainly shedded through trypomastigote extracellular vesicles, of which they are an abundant constituent, despite its scarce expression on culture-derived trypomastigotes. In contrast, TcTASV-C is highly expressed in bloodstream trypomastigotes; its upregulation in bloodstream parasites was observed in different T. cruzi strains and was specific for TcTASV-C, suggesting that some host-molecules trigger TcTASV-C expression. TcTASV-C is also strongly secreted by bloodstream parasites. A DNA prime-protein boost immunization scheme with TcTASV-C was only partially effective to control the infection in mice challenged with a highly virulent T. cruzi strain. Vaccination triggered a strong humoral response that delayed the appearance of bloodstream trypomastigotes at the early phase of the infection. Linear epitopes recognized by vaccinated mice were mapped within the TcTASV-C family motif, suggesting that blockade of secreted TcTASV-C impacts on the settlement of infection. Furthermore, although experimental and naturally T. cruzi-infected hosts did not react with antigens from extracellular vesicles, vaccinated and challenged mice recognized not only TcTASV-C but also other vesicle-antigens. We hypothesize that TcTASV-C is involved in the establishment of the initial T. cruzi infection in the mammalian host. Altogether, these results point towards TcTASV-C as a novel secreted virulence factor of T. cruzi trypomastigotes.
Assuntos
Sangue/parasitologia , Doença de Chagas/parasitologia , Vesículas Extracelulares/parasitologia , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/metabolismo , Fatores de Virulência/metabolismo , Animais , Doença de Chagas/sangue , Doença de Chagas/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C3H , Família Multigênica , Transporte Proteico , Proteínas de Protozoários/genética , Trypanosoma cruzi/genética , Fatores de Virulência/genéticaRESUMO
Underdiagnosis of chronic infection with the nematode Strongyloides stercoralis may lead to severe disease in the immunosuppressed. Thus, we have set-up a specific and highly sensitive molecular diagnosis in stool samples. Here, we compared the accuracy of our polymerase chain reaction (PCR)-based method with that of conventional diagnostic methods for chronic infection. We also analyzed clinical and epidemiological predictors of infection to propose an algorithm for the diagnosis of strongyloidiasis useful for the clinician. Molecular and gold standard methods were performed to evaluate a cohort of 237 individuals recruited in Buenos Aires, Argentina. Subjects were assigned according to their immunological status, eosinophilia and/or history of residence in endemic areas. Diagnosis of strongyloidiasis by PCR on the first stool sample was achieved in 71/237 (29.9%) individuals whereas only 35/237(27.4%) were positive by conventional methods, requiring up to four serial stool samples at weekly intervals. Eosinophilia and history of residence in endemic areas have been revealed as independent factors as they increase the likelihood of detecting the parasite according to our study population. Our results underscore the usefulness of robust molecular tools aimed to diagnose chronic S. stercoralis infection. Evidence also highlights the need to survey patients with eosinophilia even when history of an endemic area is absent.