RESUMO

Abstract Extracellular vesicles (EVs) are small vesicles released by cells that facilitate cell signaling. They are categorized based on their biogenesis and size. In the context of the central nervous system (CNS), EVs have been extensively studied for their role in both normal physiological functions and diseases like Alzheimer's disease (AD). AD is a neurodegenerative disorder characterized by cognitive decline and neuronal death. EVs have emerged as potential biomarkers for AD due to their involvement in disease progression. Specifically, EVs derived from neurons, astrocytes, and neuron precursor cells exhibit changes in quantity and composition in AD. Neuron-derived EVs have been found to contain key proteins associated with AD pathology, such as amyloid beta (Aß) and tau. Increased levels of Aß in neuron-derived EVs isolated from the plasma have been observed in individuals with AD and mild cognitive impairment, suggesting their potential as early biomarkers. However, the analysis of tau in neuron-derived EVs is still inconclusive. In addition to Aß and tau, neuron-derived EVs also carry other proteins linked to AD, including synaptic proteins. These findings indicate that EVs could serve as biomarkers for AD, particularly for early diagnosis and disease monitoring. However, further research is required to validate their use and explore potential therapeutic applications. To summarize, EVs are small vesicles involved in cell signaling within the CNS. They hold promise as biomarkers for AD, potentially enabling early diagnosis and monitoring of disease progression. Ongoing research aims to refine their use as biomarkers and uncover additional therapeutic applications.

Resumo As vesículas extracelulares (VEs) são pequenas estruturas liberadas pelas células que agem na sinalização celular. No sistema nervoso central (SNC), as VEs são estudadas em relação à doença de Alzheimer (DA), um distúrbio neurodegenerativo que cursa com declínio cognitivo e morte neuronal. As VEs podem ser biomarcadores potenciais para a DA devido ao seu papel na progressão da doença. As VEs derivadas de neurônios, astrócitos e células precursoras apresentam alterações na DA, contendo proteínas associadas à patologia da DA, como beta-amiloide (Aß) e tau. Níveis elevados de Aß foram observados nas VEs de neurônios de indivíduos com DA, sugerindo seu potencial como biomarcadores precoces. A análise de tau nas VEs de neurônios ainda é inconclusiva. Além disso, as VEs neurais carregam outras proteínas relacionadas à DA, incluindo proteínas sinápticas. As VEs podem ser promissoras como biomarcadores para o diagnóstico precoce e monitoramento da DA, porém mais pesquisas são necessárias para validar seu uso e explorar aplicações terapêuticas. Em resumo, as VEs são vesículas envolvidas na sinalização celular no SNC, com potencial como biomarcadores para a DA.

RESUMO

A esporotricose é uma zoonose micótica emergente e subcutânea, que afeta a pele, o sistema linfático e outros órgãos de humanos e animais. Assim como outras doenças infecciosas fúngicas, se torna ainda mais grave quando acomete pacientes imunossuprimidos. Essa infecção possui distribuição global e é endêmica em algumas regiões do Brasil e de outros países tropicais e subtropicais, sendo um problema de saúde pública importante em nosso país. A doença é causada por um complexo de pelo menos quatro espécies patogênicas, incluindo o Sporothrix brasiliensis (S. brasiliensis). A resposta imunológica contra estas espécies ainda não é completamente elucidada, mas estruturas como as vesículas extracelulares (VEs) poderiam transportar componentes importantes que podem contribuir na modulação e no controle desta importante infecção. Assim, o objetivo deste trabalho, é analisar a participação das VEs de células dendríticas (DCs) naive e VEs de DCs previamente primadas com leveduras de S. brasiliensis e primadas com VEs do fungo, na resposta imune contra a esporotricose experimental em modelos murinos. Para isso, as DCs obtidas da medula óssea de camundongos, foram cultivadas com leveduras de S. brasiliensis ou com VEs do fungo e posteriormente, VEs totais das DCs foram purificadas a partir de ultracentrifugação e analisadas quanto a sua participação na modulação da resposta imunológica. Essas VEs foram utilizadas em protocolo profilático em modelos murinos, previamente a infecção subcutânea experimental. Foi observado o diâmetro médio das lesões no decorrer de 35 dias de infecção e a carga fúngica da lesão na pele. Os resultados obtidos mostram que as VEs de DCs naive, e VEs de DCs previamente cultivadas com leveduras do fungo ou com VEs fúngicas, são capazes de modular a carga fúngica. Os grupos que receberam VEs de DCs de forma profilática, de modo geral apresentaram diminuição significativa da carga fúngica em relação ao grupo controle. Na análise comparativa apenas dos grupos que receberam a profilaxia, observa-se que o uso de VEs de DCs naive, resultam em uma carga fúngica maior que o uso de VEs de DCs previamente ativadas, e quando as DCs são ativadas com levedura, essa carga fúngica é a menor. Quando analisamos o perfil de citocinas na pele de camundongos tratados com as VEs previamente a infecção, observamos aumento de IFN-γ, TNF-α, IL-17 e IL-10 principalmente nos animais previamente tratados com VEs de DCs que foram ativadas com leveduras. Em relação às citocinas produzidas, podemos sugerir até o momento, uma resposta imunológica mista, mas que de alguma maneira, ainda não esclarecida, devem contribuir para melhor controle do processo infeccioso in vivo. Em relação a linfoproliferação, observa-se principalmente um aumento de linfócitos T CD4+ quando acrescentamos VEs de DCs que não foram previamente ativadas, mostrando uma ação de uma resposta mais inespecífica. Vale ressaltar que todos os protocolos profiláticos foram capazes de modular e minimizar o crescimento fúngico, quando comparados ao controle, ou seja, as VEs contribuíram com o controle da infecção e agiram a favor do hospedeiro, demonstrando um caráter protetivo

Sporotrichosis is an emerging subcutaneous mycotic zoonosis that affects the skin, lymphatic system, and other organs of humans and animals, and like other infectious fungal diseases, it becomes even more serious when it affects immunosuppressed patients. This infection has a global distribution and is endemic in some regions of Brazil and other tropicals and subtropicals countries, being an important public health problem in our country. The disease is caused by a complex of at least four pathogenic species, including Sporothrix brasiliensis (S. brasiliensis). The immunological response against these species has not yet been completely elucidated, but structures such as extracellular vesicles (EVs) could carry important components that can contribute to the modulation and control of this important infection. Thus, the objective of this work is to analyze the participation of EVs from naïve dendritic cells (DCs) and EVs from DCs previously primed with S. brasiliensis yeast and primed with EVs from the fungus, in the immune response against experimental sporotrichosis in murine models. For this, DCs obtained from the bone marrow of mice were cultivated with S. brasiliensis yeast or EVs from the fungus, and subsequently, total EVs from the DCs were purified through ultracentrifugation and analyzed for their participation in modulating the immune response. These EVs were used in a prophylactic protocol in murine models, before experimental subcutaneous infection. The average diameter of the lesions over 35 days of infection and the fungal load of the lesion on the skin were observed. The results obtained show that EVs from naïve DCs, and EVs from DCs previously cultured with yeast or fungal EVs, are capable of modulating the fungal load. The groups that received EVs from DCs prophylactically generally showed a significant decrease in fungal load compared to the control group. In the comparative analysis of only the groups that received prophylaxis, it was observed that the use of EVs from naïve DCs results in a higher fungal load than the use of EVs from previously activated DCs, and when the DCs are activated with yeast, this load fungal is smaller. When we analyzed the cytokine profile in the skin of mice treated with EVs before infection, we observed an increase in IFN-γ, TNF-α, IL-17, and IL-10, mainly in animals previously treated with EVs from DCs that were activated with yeast. About the cytokines produced, we can so far suggest a mixed immunological response, but in some way, not yet clear, they should contribute to better control of the infectious process in vivo. About lymphoproliferation, an increase in CD4+ T lymphocytes is mainly observed when we add EVs from DCs that were not previously activated, showing a more nonspecific response. It is worth highlighting that all prophylactic protocols were able to modulate and minimize fungal growth, when compared to the control, that is, EVs contributed to the control of the infection and acted in favor of the host, demonstrating a protective character

Assuntos

RESUMO

A esporotricose é uma zoonose micótica emergente e subcutânea, que afeta a pele, o sistema linfático e outros órgãos de humanos e animais. Assim como outras doenças infecciosas fúngicas, se torna ainda mais grave quando acomete pacientes imunossuprimidos. Essa infecção possui distribuição global e é endêmica em algumas regiões do Brasil e de outros países tropicais e subtropicais, sendo um problema de saúde pública importante em nosso país. A doença é causada por um complexo de pelo menos quatro espécies patogênicas, incluindo o Sporothrix brasiliensis (S. brasiliensis). A resposta imunológica contra estas espécies ainda não é completamente elucidada, mas estruturas como as vesículas extracelulares (VEs) poderiam transportar componentes importantes que podem contribuir na modulação e no controle desta importante infecção. Assim, o objetivo deste trabalho, é analisar a participação das VEs de células dendríticas (DCs) naive e VEs de DCs previamente primadas com leveduras de S. brasiliensis e primadas com VEs do fungo, na resposta imune contra a esporotricose experimental em modelos murinos. Para isso, as DCs obtidas da medula óssea de camundongos, foram cultivadas com leveduras de S. brasiliensis ou com VEs do fungo e posteriormente, VEs totais das DCs foram purificadas a partir de ultracentrifugação e analisadas quanto a sua participação na modulação da resposta imunológica. Essas VEs foram utilizadas em protocolo profilático em modelos murinos, previamente a infecção subcutânea experimental. Foi observado o diâmetro médio das lesões no decorrer de 35 dias de infecção e a carga fúngica da lesão na pele. Os resultados obtidos mostram que as VEs de DCs naive, e VEs de DCs previamente cultivadas com leveduras do fungo ou com VEs fúngicas, são capazes de modular a carga fúngica. Os grupos que receberam VEs de DCs de forma profilática, de modo geral apresentaram diminuição significativa da carga fúngica em relação ao grupo controle. Na análise comparativa apenas dos grupos que receberam a profilaxia, observa-se que o uso de VEs de DCs naive, resultam em uma carga fúngica maior que o uso de VEs de DCs previamente ativadas, e quando as DCs são ativadas com levedura, essa carga fúngica é a menor. Quando analisamos o perfil de citocinas na pele de camundongos tratados com as VEs previamente a infecção, observamos aumento de IFN-γ, TNF-α, IL-17 e IL-10 principalmente nos animais previamente tratados com VEs de DCs que foram ativadas com leveduras. Em relação às citocinas produzidas, podemos sugerir até o momento, uma resposta imunológica mista, mas que de alguma maneira, ainda não esclarecida, devem contribuir para melhor controle do processo infeccioso in vivo. Em relação a linfoproliferação, observa-se principalmente um aumento de linfócitos T CD4+ quando acrescentamos VEs de DCs que não foram previamente ativadas, mostrando uma ação de uma resposta mais inespecífica. Vale ressaltar que todos os protocolos profiláticos foram capazes de modular e minimizar o crescimento fúngico, quando comparados ao controle, ou seja, as VEs contribuíram com o controle da infecção e agiram a favor do hospedeiro, demonstrando um caráter protetivo

Sporotrichosis is an emerging subcutaneous mycotic zoonosis that affects the skin, lymphatic system, and other organs of humans and animals, and like other infectious fungal diseases, it becomes even more serious when it affects immunosuppressed patients. This infection has a global distribution and is endemic in some regions of Brazil and other tropicals and subtropicals countries, being an important public health problem in our country. The disease is caused by a complex of at least four pathogenic species, including Sporothrix brasiliensis (S. brasiliensis). The immunological response against these species has not yet been completely elucidated, but structures such as extracellular vesicles (EVs) could carry important components that can contribute to the modulation and control of this important infection. Thus, the objective of this work is to analyze the participation of EVs from naïve dendritic cells (DCs) and EVs from DCs previously primed with S. brasiliensis yeast and primed with EVs from the fungus, in the immune response against experimental sporotrichosis in murine models. For this, DCs obtained from the bone marrow of mice were cultivated with S. brasiliensis yeast or EVs from the fungus, and subsequently, total EVs from the DCs were purified through ultracentrifugation and analyzed for their participation in modulating the immune response. These EVs were used in a prophylactic protocol in murine models, before experimental subcutaneous infection. The average diameter of the lesions over 35 days of infection and the fungal load of the lesion on the skin were observed. The results obtained show that EVs from naïve DCs, and EVs from DCs previously cultured with yeast or fungal EVs, are capable of modulating the fungal load. The groups that received EVs from DCs prophylactically generally showed a significant decrease in fungal load compared to the control group. In the comparative analysis of only the groups that received prophylaxis, it was observed that the use of EVs from naïve DCs results in a higher fungal load than the use of EVs from previously activated DCs, and when the DCs are activated with yeast, this load fungal is smaller. When we analyzed the cytokine profile in the skin of mice treated with EVs before infection, we observed an increase in IFN-γ, TNF-α, IL-17, and IL-10, mainly in animals previously treated with EVs from DCs that were activated with yeast. About the cytokines produced, we can so far suggest a mixed immunological response, but in some way, not yet clear, they should contribute to better control of the infectious process in vivo. About lymphoproliferation, an increase in CD4+ T lymphocytes is mainly observed when we add EVs from DCs that were not previously activated, showing a more nonspecific response. It is worth highlighting that all prophylactic protocols were able to modulate and minimize fungal growth, when compared to the control, that is, EVs contributed to the control of the infection and acted in favor of the host, demonstrating a protective character

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RESUMO

Gram-negative bacteria are major pathogens that develop antibiotic resistance and cause distinct types of infections. According to the WHO (World Health Organization), bacterial resistance is considered a public health problem. Multiresistance Klebsiella pneumoniae and E. coli are prevalent in many hospitals. These bacteria produce outer membrane vesicles (OMVs) these vesicles can contribute to bacterial survival by eliminating toxic compounds, removing misfolded periplasmic proteins, establishing a colonization niche, biofilm formation, drug delivery, and modulation of host defense and response. This work aimed to evaluate the production and extraction of OMVs produced by E. coli and K. pneumoniae, comparing two different gel filtration and ultracentrifugation methods. Furthermore, we evaluated the interference of OMVs on the growth of enteropathogenic E. coli, uropathogenic E. coli, and hematophatogenic K. pneumoniae strains verifying the viability test. The gel filtration extraction system obtained an elevated concentration when compared to ultracentrifugation method. We observed the presence of OmpA by eletrophoresis and Dot blotting, responsible for the structure of OMVs. The results showed interferences of OMV EC086-UC, EC086-GF and OMV-KP70 on E2348/69 growth were directly proportional to the concentration of OMVs but inversely proportional to the concentration of OMVs with OMV-KP70 on EC086 and KP70 growth. We concluded that vesicle interference on EC086, E2348/69, and KP70 growth should not be based only on optical density parameters but complemented with the viability test of each bacterium strain. The use of biotechnology tools like genetic modifications, OMVs can perform multiple functions carrying molecules with many capabilities to be applied in many fields such as immunology, diagnostics, clinical medicine.

As bactérias Gram-negativas são patógenos que apresentam resistência a diversos antibióticos. De acordo com a Organização Mundial da Saúde (OMS), a resistência antimicrobiana é um problema de saúde pública. A Escherichia coli e a Klebsiella pneumoniae são multirresistentes e prevalentes nos ambientes hospitalares. Estas bactérias produzem vesículas de membrana externa (OMVs) e possuem diversas funções como: contribuição para a sobrevivência das bactérias através da neutralização de componentes tóxicos, eliminação de proteínas desnaturadas, estabelecimento do nicho de colonização, formação de biofilme, entrega de drogas, modulação do sistema de defesa e resposta imune. Este trabalho avaliou a produção e extração de OMVs produzidas por cepas de E. coli e K. pneumoniae comparando os métodos de extração das mesmas por da gel filtração e ultracentrifugação. Além disso, através do teste de viabilidade bacteriana avaliamos a interferência das OMVs no crescimento de E. coli enteropatogência, E. coli uropatogênica e K. pneumoniae hematopatogênica. A purificação das OMVs por gel filtração apresentou uma concentração elevada quando comparada com o método de ultracentrifugação. Identificamos, para ambos os métodos, através da eletroforese e imunoensaio a presença da proteína de membrana externa a OmpA, responsável pela estrutura das OMVs. Demonstramos pelos resultados que as EC086-UC, EC086-GF e OMV-KP70 interferiram no crescimento da cepa E2348/69 com padrão diretamente proporcional quando comparado com a concentração das vesículas. O contrário ocorreu na interferência da OMV KP70-UC, atuando sobre o crescimento de EC086 e KP70 de forma inversamente proporcional quando comparado com a concentração das vesículas. Concluímos que a interferência das vesículas sobre o crescimento deve levar em conta os parâmetros de densidade óptica e a viabilidade bacteriana. Assim, com as diversas ferramentas da biotecnologia como a engenharia genética podemos desenvolver OMVs capazes de carrear diversas moléculas e ser aplicada em vários campos da imunologia, diagnósticos e na medicina clínica.

RESUMO

Resumen Las vesículas extracelulares son nanoparticulas secretadas por células procariotas y eucariotas, con funciones variadas que van desde la comunicación intercelular hasta la modulación de la respuesta inmune. La investigación en este tema se enfocó inicialmente en el aislamiento, identificación y caracterización, para luego abarcar los mecanismos fisiológicos en los que se ven involucradas. Más recientemente, la investigación, particularmente centrada en exosomas, ha permitido abrir campo a novedosas hipótesis sobre su utilidad en inmunoterapia y como marcadores biológicos. Esta revisión explora aspectos básicos sobre la biogénesis y la composición de los exosomas, así como su uso en diagnóstico y tratamiento, a partir del conocimiento generado sobre su aislamiento y purificación, distribución de cargos específicos y su relación con la respuesta inmune. Los hallazgos sobre su aplicabilidad en procesos cancerosos son promisorios; sin embargo, existe toda una ventana de posibilidades para investigar esta plataforma molecular como potenciales vacunas acelulares y marcadores de pronóstico, diagnóstico y alerta, tanto en cáncer como en patologías causadas por agentes infecciosos.

Abstract Extracellular vesicles are nanoparticles released by prokaryotic and eukaryotic cells, with a variety of functional roles in intercellular communication and even in modulation of the immune response. Research in this topic was initially focused on isolation, identification and characterization of the vesicles, with subsequent understanding of the physiological mechanisms in which they are involved. Furthermore, recent studies, particularly with exosomes, have opened the field to novel hypotheses about their usefulness in immunotherapy and as biological markers. This review explores general aspects about the biogenesis and composition of exosomes, as well as their potential use in diagnosis and treatment, based on the knowledge generated about their isolation, production, cargoes, delivery engineering and relationship with the immune response. The findings on its applicability in cancerous processes are promising, but there is still a variety of investigation possibilities of this molecular platforms as cell-free vaccines and as prognostic, diagnostic and/or warning markers, both in cancer but also in infectious diseases.

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Por ser uma célula altamente especializada, o espermatozoide apresenta diferentes mecanismos epigenéticos, sendo os principais as metilações do DNA, o código de histonas, os ncRNAs (RNAs não codificadores), e a alta condensação da cromatina pela presença das protaminas. Estes mecanismos interagem entre si, contribuindo para a formação do epigenoma espermático, que modela a carga molecular espermática, que, por sua vez, pode impactar sobre as características do desenvolvimento embrionário e da progênie. Dessa forma, atualmente é consenso que o papel do espermatozoide ultrapassa a entrega de DNA de qualidade para o oócito no momento da fecundação. Pesquisas recentes de diversos grupos, incluindo o nosso, mostram que além da contribuição com DNA de qualidade, o espermatozoide entrega moléculas ao oócito no momento da fecundação que influenciam o desenvolvimento do embrião. Recentemente, essas moléculas de origem espermática (Em inglês: sperm-borne) também são associadas com alterações metabólicas e cognitivas da progênie. Embora ainda pouco se entenda como esses mecanismos podem persistir mesmo com o ciclo de reprogramação celular que ocorre logo após a fecundação, é evidente que estes podem impactar as características da progênie. Nesta revisão abordaremos sobre a modulação do epigenoma espermático e seus efeitos no desenvolvimento embrionário.(AU)

Since it is a highly specialized cell, the spermatozoa display different epigenetic mechanisms; the main ones are DNA methylation, histone code, ncRNAs (non-coding RNAs), and high chromatin condensation by the presence of protamines. These mechanisms act in synergy contributing to forming the sperm epigenome, which modulates the spermatic molecular cargo, and, may impact embryo and offspring development features. Thus, it is currently a consensus that the role of spermatozoa goes beyond delivering quality DNA to the oocyte at fertilization. Relevant findings from several research groups, including ours, have shown that sperm delivers several molecules to the oocyte at fertilization, beyond the contribution to DNA, which influences the development of the embryo. Recently, these sperm-borne molecules have also been associated with metabolic and cognitive changes in the offspring. Although the mechanism by which these changes can persist even after embryo reprogramming is not completely understood, evidence shows that sperm cell molecular content impacts embryo and offspring development. This review will mainly focus on the modulation of the sperm epigenome and its effects on embryo development.(AU)

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Abstract The study of outer membrane vesicles (OMVs) became relevant because of theirprobable important role in the transfer of virulence factors to host cells. Campylobacter fetusis mainly a mammal pathogen whose virulence characterization is still limited. The aim of thisstudy was to evaluate and to characterize the secretion of OMVs in this bacterium. By trans-mission electron microscopy, we confirmed the production of OMVs in all the strains assayed.Purified OMVs showed a spherical shape and variable size, although comparable to those ofother gram-negative bacteria. We also confirmed the presence of the S-layer on the surface ofthe OMVs of all the strains assayed with the exception of those derived from the NTCC referencestrain. In addition, we demonstrated their immunoreactivity by the dot-blot assay. Hence, C.fetus OMVs could contribute to the modulation of the host response and constitute a candidateto be evaluated as an adjuvant of current vaccines used in the veterinary field. This work rep-resents a platform to drive future studies towards the role of these subcellular structures in C.fetus-host interaction.

Resumen El estudio de las vesículas de membrana externa (VME) tomó un rol protagónico, yaque se las ha relacionado con la transferencia de factores de virulencia a la célula hospedadora.Campylobacter fetus es, principalmente, un patógeno de mamíferos cuya virulencia solo hasido caracterizada de forma limitada. El objetivo de este trabajo fue evaluar y caracterizar la secreción de VME en esta bacteria. Mediante microscopía electrónica de transmisión confir-mamos la producción espontánea de VME en todas las cepas estudiadas. Las VME purificadasmostraron una morfología esférica y un tama˜no variable, pero compatible con el reporte deotras bacterias gram negativas. Asimismo, hemos demostrado que estas vesículas conservanla capa S en todas las cepas, menos en la cepa de referencia NCTC y hemos confirmado suinmunorreactividad por dot-blot inmunoblot. Estas VME de C. fetus podrían contribuir a la mod-ulación de la respuesta del hospedador y constituir un buen candidato como adyuvante de lasactuales vacunas empleadas en el campo veterinario. Este trabajo representa una plataformapara impulsar estudios futuros en torno al rol de estas estructuras subcelulares en la interfaseC. fetus-hospedador.

RESUMO

Introducción: Los exosomas son vesículas extracelulares de tamaño nanométrico, que se generan cuando los endosomas multivesiculares se fusionan con la membrana plasmática y el contenido de las vesículas intraluminales se libera en el espacio extracelular. Son producidos por casi todos los tipos de células, en condiciones fisiológicas y patológicas. Transportan proteínas, lípidos y ácido ribonucleico (ARN) no codificante, desde la célula madre hasta la célula receptora, estos son considerados un punto clave en la regeneración de tejidos, lo que se ha demostrado en una serie de estudios, con diferentes tejidos corporales, como piel, cartílago, pancreático y tejidos cardiovasculares. Objetivo: Explicar los aspectos generales y posibles usos de los exosomas en el campo médico. Métodos: Se realizó una búsqueda de información mediante consulta en las bases de datos SciELO PubMed, Science Direct y Lilacs, en los idiomas español e inglés, con diferentes combinaciones de palabras claves y términos MESH como: exosomes, neovascularization, wound healing, immunity, micro RNA, immunology, therapy, classification. Se efectuó un análisis y resumen de la información revisada. Conclusiones: En la actualidad, los exosomas se han convertido en objeto de investigación para diversos tratamientos, medicamentos y uso como marcadores moleculares. Se destacan en terapias contra el cáncer, la inmunomodulación, la estimulación o supresión de la angiogénesis, regeneración cutánea, cicatrización y curación de heridas; por lo que de forma general resultan prometedores en el ámbito de las ciencias médicas(AU)

Introduction: Exosomes are nano-sized extracellular vesicles, which are generated when multivesicular endosomes fuse with the plasma membrane and the content of intraluminal vesicles released into the extracellular space. Are produced by almost all types of cells, under physiological and pathological conditions and they transport proteins, lipids and non-coding RNA (ribonucleic acid), from the stem cell to the recipient cell, these are considered a key point in tissue regeneration, which has been shown in a series of studies, with different body tissues, such as skin, cartilage, pancreatic and cardiovascular tissues. Objective: To explain the general aspects and possible uses of exosomes in the medical field. Methods: A search for information was carried out by consulting the Scielo, PubMed, ScienceDirect and Lilacs databases, in Spanish and English, with different combinations of keywords and MESH terms such as: exosomes, neovascularization, wound healing, immunity, microRNA, immunology, therapy, classification. Then, an analysis and summary of the reviewed information was carried out. Conclusions: Currently, exosomes have become the object of research for various treatments, drugs, and their use as molecular markers. They stand out in cancer therapies, immunomodulation, stimulation or suppression of angiogenesis, skin regeneration, and wound healing, which is why they are generally promising in the field of medical sciences(AU)

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SUMMARY: Exosomes are small and single-membrane secreted organelles, up to 200 nm in diameter that have the same topology as the cell, but are enriched in proteins, nucleic acids, lipids, and glycoconjugates. It can be found in any type of body fluids such as plasma, urine, saliva, sperm, bile, etc. On the other hand, cystic Echinococcosis (CE) has been studied from different points of view, among others, from genomics and proteomics, and the presence of CE exosomes in humans and other intermediate hosts has been reported in very few articles. The aim of this review was to report the evidence available regarding exosomes and CE. Systematic review. Data sources: Trip Database, SciELO, WoS, MEDLINE, EMBASE and SCOPUS. Eligibility criteria: Studies related to CEin any type of host and state of the parasite, without language restriction, published between 1966-2021. Variables: Year of publication, geographical origin, species isolated, location of exosomes. Forty-two studies were initially identified. After scrutinizing titles and abstracts, checking duplications and in-depth analysis of the studies selected, 12 articles including human, bovine, sheep, dog samples were also included. All were case reports or case series. The highest proportion of articles was published between 2019 and 2021 (58.3 %). Publications were predominantly from China (58.3 %). Evidence about exosomes and CE is scarce and reduced range of articles and cases.

RESUMEN: Los exosomas son orgánulos pequeños y secretados por una sola membrana, de hasta 200 nm de diámetro que tienen la misma topología que la célula, pero están enriquecidos en proteínas, ácidos nucleicos, lípidos y glicoconjugados. Se puede encontrar en cualquier tipo de fluidos corporales como plasma, orina, saliva, esperma, bilis, etc. Por otro lado, la equinococosis quística (CE) ha sido estudiada desde diferentes puntos de vista, entre otros, desde la genómica y proteómica, y la presencia de exosomas de CE en humanos y otros huéspedes intermediarios se ha informado en muy pocos artículos. El objetivo de esta revisión fue informar la evidencia disponible con respecto a los exosomas y la CE. Revisión sistemática. Fuentes de datos: Trip Database, SciELO, WoS, MEDLINE, EMBASE y SCOPUS. Criterios de elegibilidad: Estudios relacionados con la EC en cualquier tipo de hospedador y estado del parásito, sin restricción de idioma, publicados entre 1966-2021. Variables: año de publicación, origen geográfico, especie aislada, ubicación de exosomas. Se identificaron inicialmente 42 estudios. Después de examinar los títulos y resúmenes, verificar las duplicaciones y analizar en profundidad los estudios seleccionados, se incluyeron 12 artículos que incluían muestras de humanos, bovinos, ovinos y caninos. Todos fueron informes de casos o series de casos. La mayor proporción de artículos se publicó entre 2019 y 2021 (58,3 %). Las publicaciones fueron predominantemente de China (58,3 %). La evidencia sobre exosomas y CE es escasa y la gama de artículos y casos es reducida.

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The study of outer membrane vesicles (OMVs) became relevant because of their probable important role in the transfer of virulence factors to host cells. Campylobacter fetus is mainly a mammal pathogen whose virulence characterization is still limited. The aim of this study was to evaluate and to characterize the secretion of OMVs in this bacterium. By transmission electron microscopy, we confirmed the production of OMVs in all the strains assayed. Purified OMVs showed a spherical shape and variable size, although comparable to those of other gram-negative bacteria. We also confirmed the presence of the S-layer on the surface of the OMVs of all the strains assayed with the exception of those derived from the NTCC reference strain. In addition, we demonstrated their immunoreactivity by the dot-blot assay. Hence, C. fetus OMVs could contribute to the modulation of the host response and constitute a candidate to be evaluated as an adjuvant of current vaccines used in the veterinary field. This work represents a platform to drive future studies towards the role of these subcellular structures in C. fetus-host interaction.

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Resumen En la última década se ha incrementado el número de estudios y publicaciones sobre las vesículas extracelulares y los exosomas. En Colombia, ha habido interés y avances en su estudio, lo que se evidencia en el aumento de publicaciones y proyectos de investigación. Sin embargo, este es un campo de investigación aún en desarrollo, con desafíos analíticos y limitaciones técnicas, por lo cual, en el planteamiento de los proyectos de investigación y desarrollo, es necesario considerar cuál es el estado del campo científico a nivel mundial en cuanto a la nomenclatura y la clasificación de las vesículas extracelulares, las técnicas, recursos, requisitos y especificaciones de calidad y las instituciones que regulan el campo. La respuesta a esta pregunta permitirá desarrollar estudios que cumplan con los estándares internacionales, y las exigencias y recomendaciones institucionales. Sin embargo, la información científica disponible se encuentra dispersa y no todos los aspectos son tratados a cabalidad. En este actualización se condensa la información disponible y se presentan los términos oficiales para denominar las vesículas extracelulares y la nomenclatura aceptada actualmente, así como la evolución del campo, la homogenización de los parámetros experimentales, el establecimiento de autoridades científicas, instituciones y recursos, y las recomendaciones que se han generado a nivel mundial para el desarrollo de investigaciones en vesículas extracelulares, incluidos su aislamiento, caracterización y estudio funcional. Por último, se analiza el contexto nacional de una forma crítica, teniendo en cuenta las fortalezas institucionales, los errores usualmente cometidos, y las técnicas y tecnologías analíticas disponibles.

Abstract In the last decade, the number of studies and publications on extracellular vesicles (EV) and exosomes has boomed. Colombia has displayed interest and progress in their study as shown in the increase of research project publications and products. However, this research field is still developing and has its own analytical challenges and technical limitations. For planning research projects and developing EV studies it is necessary to consider what is the state of the scientific field worldwide concerning EV nomenclature and classification, available techniques, resources, requirements and quality specifications, and the institutions that regulate the field. Answering this question will elicit EV studies that comply with international standards and respond to institutional demands and recommendations. However, the scientific information available is scattered and not all the aspects are considered in full. In this update, the available information is condensed and the official terms and currently defined nomenclature is presented, as well as the evolution of the field, the homogenization of the experimental parameters, the establishment of scientific authorities, institutions, and resources, and the recommendations generated worldwide for their development and research including their isolation, characterization, and functional studies. Finally, I analyzed the national context in a critical way, considering institutional strengths, common mistakes, and available analytical techniques and technologies.

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Introducción: Las enfermedades infecciosas del tracto respiratorio se encuentran entre las primeras causas de entidades respiratorias en edades extremas de la vida. Objetivo: Describir las bases inmunológicas de la enfermedad y el nuevo candidato vacunal conjugado antineumocócico PCV7-TT desarrollado en Cuba. Métodos: Se realizó una búsqueda en las bases de datos Medline, Pubmed, SciELO, LILACS, Cochrane Library y Web of Science, de documentos publicados entre mayo del 2018 y marzo del 2020. Se seleccionaron los 64 artículos de mayor relevancia y novedad. Resultados: Streptococcus pneumoniae es el agente etiológico de la enfermedad neumocócica; se le atribuye alrededor de un millón de defunciones anuales, principalmente en países en vías de desarrollo. Es un coco Gram-positivo, anaerobio facultativo y encapsulado que se encuentra dividido en 48 serogrupos y 97 serotipos tipificados. Presenta varios factores de virulencia que garantizan su mecanismo de patogenicidad; uno de los más importantes es el polisacárido capsular que constituye la diana de las vacunas antineumocócicas conjugadas y no conjugadas existentes. En el presente artículo se consideró la proteína de superficie C del neumococo como un posible candidato en la investigación y desarrollo de vacunas preventivas. Asimismo, las vesículas extracelulares podría ser un posible candidato para adyuvante vacunal con fines preventivos y terapéuticos. Conclusiones: El neumococo es un problema de salud a nivel global y el uso de vacunas conjugadas antineumocócicas constituye la herramienta más eficaz para su prevención. El candidato vacunal PCV7-TT desarrollado en Cuba es seguro, bien tolerado, inmunogénico y no inferior a las vacunas actualmente registradas(AU)

Introduction: Infectious diseases of the respiratory tract are among the leading causes of respiratory conditions in patients at extreme ages. Objective: Describe the immunological bases of the disease and the new conjugate pneumococcal vaccine candidate PCV7-TT developed in Cuba. Methods: A search was conducted in the databases Medline, Pubmed, SciELO, LILACS, Cochrane Library and Web of Science for documents published from May 2018 to March 2020. The 64 most relevant and novel papers were selected. Results: Streptococcus pneumoniae is the causative agent of pneumococcal disease, a condition causing about one million deaths a year worldwide, mainly in developing countries. It is a Gram-positive facultative anaerobic encapsulated coccus divided into 48 serogroups and 97 typified serotypes. Several virulence factors ensure its pathogenicity mechanism. One of the most important of these is the capsular polysaccharide constituting the target of the existing conjugate and non-conjugate pneumococcal vaccines. The study considered pneumococcal surface protein C as a possible candidate for the research and development of preventive vaccines. On the other hand, extracellular vesicles could be a possible vaccine adjuvant candidate for preventive and therapeutic use. Conclusions: Pneumococcus is a global health problem, and the use of conjugate pneumococcal vaccines is the most effective tool for its prevention. The vaccine candidate PCV7-TT developed in Cuba is safe, well-tolerated, immunogenic and not inferior to the vaccines so far registered(AU)

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La gingivoestomatitis herpética corres-ponde a la manifestación primaria de la infección por virus herpes simple tipo I que se presenta con mayor frecuencia en lactantes mayores y preescolares. Objeti-vo: describir abordaje y manejo de gingi-vo estomatitis herpética en una paciente con cardiopatía congénita y cuadro de desnutrición severa. El caso se refiere a paciente femenina de 16 meses de edad a quien le fue realizado anamnesis, exa-men clínicoe interconsultas con servicios de pediatría, patología, medicina bucal, infectología. El diagnóstico incluyó co-municación intraventricular, desnutrición severa y gingivoestomatitis herpética. Se realizó tratamiento paliativo para el dolor, terapia antiviral (aciclovir en suspensión 1cc cada 6 horas por 7 días) y tratamiento tópico (sucralfato en suspensión 1g/5ml mezclado en partes iguales con cetirizina en suspensión. 5 mg / 5 ml, 3 veces al día directamente sobre las lesiones) durante 14 días logrando reducción de la sintoma-tologia. Conclusiones: el correcto manejo multidisciplinario permitió lograr dismi-nución en tamaño y número de las lesio-nes en cavidad oral, orientación dietética y canalización apropiada.

A gengivoestomatite herpética correspon-de à manifestação primária da infecção pelo vírus herpes simplex tipo I, que ocorre com mais frequência em bebês e em idade pré-escolar. Objetivo: descrever a aborda-gem e o tratamento da estomatite herpética gengival em um paciente com cardiopatia congênita e desnutrição grave. O caso re-fere-se a uma paciente de 16 meses de ida-de, submetida a anamnese, exame clínico e interconsultas com serviços de pediatria, patologia, medicina bucal, infectologia. O diagnóstico incluiu comunicação intraven-tricular, desnutrição grave e gengivosto-matite herpética. Foram realizados trata-mento paliativo para dor, terapia antiviral (suspensão de aciclovir 1cc a cada 6 horas por 7 dias) e tratamento tópico (suspensão de sucralfato 1g / 5ml misturado em partes iguais com suspensão de cetirizina 5mg / 5ml, 3 vezes ao dia diretamente. lesões) por 14 dias, alcançando redução dos sintomas. Conclusões: o correto manejo multidisci-plinar permitiu diminuir o tamanho e o número de lesões na cavidade oral, orien-tação alimentar e canalização adequada.

Herpetic gingivostomatitis is the pri-mary manifestation of herpes simplex virus type I infection, common in older infants and preschoolers. Objective: to describe the approach and management of herpetic stomatitis in a patient with congenital heart disease and severe mal-nutrition. The case refers to a 16-mon-th-old female patient who underwent an anamnesis, clinical examination, and inter-consultations with pediatric, pa-thological, oral medicine services, and Diagnosis included intraventricular communication, severe malnutrition, and herpetic gingivostomatitis. Palliati-ve treatment for pain, antiviral therapy (acyclovir suspension 1cc every 6 hours for 7 days) and topical treatment (sucral-fate suspension 1g / 5ml mixed in equal parts with cetirizine suspension 5mg / 5ml, 3 times a day directly, were perfor-med. about injuries) for 14 days. Conclu-sions: multidisciplinary, management, allowed to obtain, clinical diagnosis and establish a treatment plan with positive outcome,decreasing oral cavity dietary guidance and appropriate channeling.

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La terapia celular basada en células mesenquimales/estromales se aplica ampliamente en la medicina moderna, aun cuando no todos los mecanismos de supervivencia y diferenciación están identificados. Sin embargo, hace pocos años se comenzaron a encontrar elementos extracelulares que generan nuevos paradigmas. En el presente trabajo se explican las principales características y funciones atribuidas a los exosomas, nanopartículas constituidas por microvesículas secretadas por las células con efecto en la matriz extracelular, y su repercusión como alternativa hacia una medicina regenerativa libre de células. Estas estructuras participan de forma notoria y crucial en la comunicación intercelular, lo que ha supuesto un cambio en el concepto de las funciones y el papel que desempeñan estas vesículas en los organismos vivos, en particular en la restauración de tejidos dañados y la respuesta inflamatoria e inmunológica. Se comentan algunos ejemplos de la repercusión biotecnológica de los exosomas en empresas y el mercado biofarmaceútico(AU)

Mesenchymal/stromal cell ;based therapy is widely applied in modern medicine, even though not all survival and differentiation mechanisms are identified. However, a few years ago, extracellular elements began to be found that generate new paradigms. The present work explains the main characteristics and functions attributed to exosomes, nanoparticles made up of microvesicles secreted by with an effect on the extracellular matrix, and their impact as an alternative towards cell-free regenerative medicine. These structures participate, notoriously and critically, in intercellular communication, which has led to a change in the concept of the functions and role that these vesicles play within living organisms, particularly in the restoration of damaged tissues and the inflammatory and immunological response. Some examples of the exosomes' biotechnological impact on companies and the biopharmaceutical market are discussed(AU)

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A successive embryonic developmental study was conducted on the brain of twenty eight embryos and fetuses of one humped camel (Camelus Dromedarius), whose crown vertebral rump lengths (CVRL) ranged from 9 to 80 mm, collected from the El-Basateen (Cairo) and Belbees (ElSharqya) Slaughterhouse. The current investigation revealed that camel brain was found to consist of fore, mid and hind brains. The fore brain is divided into telencephalon and diencephalon while the rhombencephalon divided into metencephalon and myelencephalon. Flexures appeared between the vesicles are cervical flexure between the rhomencephalon and the spinal cord, cephalic flexure in the mesencephalon and pontine flexure between the metencephalon, and the myelencephalon of the hind brain (rhombencephalon). The cavity of the rhombencephalon is the fourth ventricle, while that of the diencephalon is the third ventricle, and those of the telencephalon are the lateral ventricles but that of mid brain is the cerebral aqueduct. myelencephalon becomes medulla oblongata and metencephalon developed to pons and cerebellum while mesencephalon gives rise to the cerebral crura and anterior and a posterior colliculus. Diencephalon gives the thalamus, hypothalamus, mamillary body, infundibulum and pineal body while telencephalon becomes the cerebral hemispheres and corpus striatum.

Se llevó a cabo un estudio del desarrollo embrionario cerebral de veintiocho embriones y fetos de camello jorobado (Camelus dromedarius). Las muestras fueron recolectadas en los mataderos de El-Basateen (El Cairo) y Belbees (ElSharqya). La investigación reveló que el cerebro de camello posee un cerebro anterior, medio y posterior. El cerebro anterior se divide en telencéfalo y diencéfalo, mientras que el rombencéfalo se divide en metencéfalo y mielencéfalo. Las flexiones encontradas entre las vesículas son la flexión cervical entre el rombencéfalo y la médula espinal; la flexión cefálica en el mesencéfalo; y la flexión pontina entre el metencéfalo y el mielencéfalo del cerebro posterior (rombencéfalo). La cavidad del rombencéfalo conforma el cuarto ventrículo, la del diencéfalo forma el tercer ventrículo, y las del telencéfalo a los ventrículos laterales. En el cerebro medio, la cavidad corresponde al acueducto cerebral. El mielencéfalo se convierte en médula oblonga y el metencéfalo deriva en puente y cerebelo, mientras que el mesencéfalo da lugar a la crura cerebral y a los colículos anterior y posterior. El diencéfalo origina el tálamo, el hipotálamo, el cuerpo mamilar, el infundíbulo y la hipófisis, mientras que del telencéfalo se originan los hemisferios cerebrales y el cuerpo estriado.

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La enfermedad boca-mano-pie puede presentarse con formas atípicas, con lesiones más generalizadas y morfología diferente a la forma clásica. A veces, incluso simula otras enfermedades víricas. En las formas atípicas, existe la tendencia a afectar a las zonas de traumatismo o inflamación. Se presenta el caso de un niño de 2 años con antecedente de atopia, que consultó por presentar lesiones papulosas y vesiculosas umbilicadas que afectaban a la zona perioral, los miembros superiores e inferiores, con predominio en las zonas de presión y de dermatitis atópica previa. Aunque clínicamente se diagnosticó eczema herpético, las pruebas complementarias fueron negativas para herpes virus. Sin embargo, la reacción en cadena de la polimerasa del contenido de una vesícula, del exudado faríngeo y de heces fue positiva para enterovirus.

Hand-foot-mouth disease can present atypically, including forms with more numerous lesions and/or morphologically different from the classic presentation. It may even mimic other viral diseases. We present the case of a 2-year-old child previously diagnosed with atopic dermatitis, who presented with papules and umbilicated vesicles affecting the perioral area and limbs, predominantly in pressure areas, as well as in areas with previous atopic lesions. Although he was clinically diagnosed with herpetic eczema, tests results were negative for herpes virus. However, positive entorovirus polymerase chain reaction results were obtained from the content of a vesicle, a pharyngeal exudate and a stool sample.

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O objetivo deste estudo foi isolar e caracterizar as vesículas extracelulares (EVs) humanas e compará-las entre grupos de indivíduos com ou sem toxoplasmose, uma zoonose de distribuição mundial e de importância na saúde pública por seu papel na gestação e na co-infecção com o vírus da imunodeficiência humana (HIV). Oitenta e três amostras clínicas foram divididas em: grupo I, 20 plasmas de indivíduos saudáveis e gestantes (soronegativos para toxoplasmose); grupo II, 21 plasmas de pacientes com toxoplasmose sintomática; grupo III, 26 amostras de líquido cefalorraquidiano (LCR) de pacientes com toxoplasmose cerebral e co-infecção por HIV (TC/aids); e grupo IV, 16 amostras de LCR de pacientes sem toxoplasmose, mas com aids e outras infecções oportunistas (OI/aids). Após a recuperação das EVs por ultracentrifugação as amostras seguiram para análise de tamanho e concentração por Análise de Rastreamento de Nanopartícupas (NTA); morfologia, por Microscopia Eletrônica de Transmissão (TEM); perfil proteico, por SDS-PAGE/Imunoblot e expressão gênica de microRNAs (miRNAs), por PCR em tempo real (qPCR). A concentração das EVs-plasma do grupo II (2,4x1010 EVs/mL) foi estatisticamente maior do que as do grupo I (5,9x109 EVs/mL). Já nas EVs-LCR a concentração foi semelhante nos dois grupos, TC/aids (2,9x109 EVs/mL) e OI/aids (4,8x109 EVs/mL). Apenas a concentração das EVs foi capaz de distinguir os pacientes com...(AU)

This study aimed to isolate and characterize EVs and compare them between groups of individuals with or without toxoplasmosis, a worldwide distribution zoonosis, that plays an important role during pregnancy and co-infection with the human immunodeficiency virus (HIV). Eighty-three samples was divided as: group I, 20 plasma of health individuals and pregnant women (negatives for toxoplasmosis); group II, 21 plasma of toxoplasmosis patients; group III, 26 samples of cerebrospinal fluid (CSF) of patients with cerebral toxoplasmosis/aids (TC/AIDS) e group IV, 16 samples of CSF of patients without toxoplasmosis, but with AIDS and others opportunistic infections (OI/AIDS). After EV isolation by ultracentrifugation, size and concentration of were measured by Nano Tracking Analisys (NTA). In addition, morphology by Transmission Electronic Microscopy (TEM), protein profile by SDS-PAGE/Imunoblot and miRNAs expression, by Real time PCR (qPCR) were performed. Concentration of plasma EVs from group II patients (2.4x1010 EVs/mL) was statistically higher than those from group I (5.9x109 EVs/mL). Concentration od CSF EVs was similar in both groups, TC/AIDS (2.9x109 EVs/mL) and OI/AIDS (4,8x109 EVs/mL). Therefore, only the concentration was able to distinguish patients with toxoplasmosis than health individuals. Exosomes were also confirmed by TEM and CD-63 and CD-9 tetraspanina detection by immunoblot. EVs-plasma from group II had higher expression of miR-125b (4.9 times) and miR-146a (4.1 times) from control group...(AU)

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Nosocomial infection it is an infection acquired by patient during the hospital stay. According to the WHO bacterial infections are a major cause of hospitalization and worldwide death. The excessive e improper use of antibiotics are elevating nosocomial infections and causes the emergence of resistant strains to these antimicrobials causing a economic impact in the country. Thus vaccines are the alternatives strategies for treating these infections. Escherichia coli is one of the leading emerging nosocomial pathogens and it’s a Gram-negative rod shaped bacterium that colonizes the gastrointestinal tract responsible for diseases such as sepsis, pneumonia, neonatal meningitis, peritonitis, and gastroenteritis. E. coli produces outer membrane vesicles (OMV) which are small spherical and highly immunogenic structures of 20-200 nm and may be an alternative vaccine against nosocomial infections. The vesicles are released during cell growth and production can be influenced by factors such as acidity, temperature, nutrient deficiency, etc. The objective of this work was to evaluate the production of OMV by E. coli strain 17/38 (provided by HU – Hospital Universitário) in shaker, using different cultivation conditions (pH, temperature and time) and extraction by tangential filtration or ultracentrifugation. For quantification and characterization of OMV, we performed protein dosage tests, electrophoresis and electron microscopy. Based on the results, we conclude that: pH, temperature and time affected the production of OMV; the OMV extraction by tangential filtration proved to be a promising technology when compared with ultracentrifugation. Despite the great knowledge regarding OMVs as mediators of virulence and to bacterial survival there are still many aspects to be elucidated regarding the impact of these OMVs on microorganisms and the human host.

As infecções hospitalares (nosocomiais) são adquiridas por pacientes em ambiente hospitalar. Segundo a OMS, as infecções bacterianas ainda são uma das principais causas de hospitalização e morte em todo o mundo. O uso excessivo inadequado de antibióticos aumenta as infecções nosocomiais em virtude do surgimento de cepas resistentes a estes antimicrobianos causando grande impacto econômico no país. Assim, as vacinas são as estratégias para tratamento destas infecções. Escherichia coli é um dos principais patógenos nosocomiais emergentes e é uma bactéria Gram-negativa em forma de bastonete que coloniza o trato gastrointestinal, responsável por várias doenças, como septicemia, pneumonia, meningite neonatal, peritonite e gastroenterite. A E. coli produz vesículas da membrana externa (OMV) que são pequenas estruturas esféricas e altamente imunogênicas de 20 a 200 nm e pode ser uma vacina alternativa contra infecções nosocomiais. As vesículas são liberadas durante o crescimento celular e a produção pode ser influenciada por fatores como acidez, temperatura, deficiência de nutrientes, etc. O objetivo deste trabalho foi avaliar a produção de OMV por E. coli cepa 17/38 (fornecida pelo HU - Hospital Universitário) em "shaker", utilizando diferentes condições do cultivo (pH, temperatura e tempo) e extração por filtração tangencial ou ultracentrifugação. Para a quantificação e caracterização de OMVs realizamos testes de dosagem de proteína, eletroforese e microscopia eletrônica. Com base nos resultados, concluímos que: o pH, temperatura e tempo afetaram a produção de OMV; extração de OMV pela filtração tangencial mostrou-se uma tecnologia promissora quando comparada com a ultracentrifugação. Assim, apesar do grande conhecimento a respeito de OMVs como mediadores de virulência e da necessidade para a sobrevivência bacteriana, ainda existem muitos aspectos a serem elucidados a respeito do impacto destas OMVs nos microrganismos e no hospedeiro humano.

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Salmonella Paratyphi A es un patógeno exclusivo de humanos, siendo la segunda causa más común de fiebre entérica en el sudeste asiático. Recientemente la incidencia en este continente ha aumentado, desplazando a Salmonella entérica serotipo Typhi como la primera causa de fiebre entérica. En la actualidad no existen vacunas licenciadas contra S. Paratyphi A. El Instituto Finlay de Vacunas se encuentra trabajando en la obtención de un candidato vacunal basado en vesículas de membrana externa (VME) contra S. Paratyphi A, por lo que se hizo necesario contar con una técnica para la evaluación de su inmunogenicidad. El objetivo de este trabajo fue la estandarización de un ELISA para la cuantificación de anticuerpos IgG contra VME de S. Paratyphi A. Para ello, se determinaron las mejores condiciones de este ensayo en cuanto a concentración óptima de recubrimiento y dilución de trabajo del conjugado. Además, se definió el intervalo y linealidad de la curva, la precisión intra e interensayo, la especificidad y el límite de detección. La curva de calibración se generó con un suero estándar interno y presentó un buen ajuste lineal con un R² =0.98. Los coeficientes de variación en los ensayos de precisión intra e interensayo estuvieron en los intervalos establecidos para cada uno (=10 por ciento, =20 por ciento respectivamente). Los resultados obtenidos avalan el empleo de este ELISA cuantitativo para la evaluación de la inmunogenicidad de formulaciones de VME de S. Paratyphi A en fases de investigación y desarrollo(AU)

Salmonella Paratyphi A, is an exclusive pathogen of humans, being the second most common cause of enteric fever in Southeast Asia. Recently the incidence of this disease in this continent has increased, displacing Salmonella enterica serotype Typhi as the first cause of enteric fever. Currently there are no vaccines licensed against S. Paratyphi A. The Finlay Institute of Vaccines is working on obtaining a vaccine candidate based on outer membrane vesicles (VME) against S. Paratyphi A, so it became necessary to develop a technique for the evaluation of its immunogenicity. The objective of this work was the standardization of an ELISA for the quantification of IgG antibodies against VME of S. Paratyphi A. The best conditions of this assay were determined in terms of optimum concentration of coating and working dilution of the conjugate. In addition, the interval and linearity of the curve, the intra- and inter-assay precision, the specificity and the limit of detection were defined. The calibration curve was generated with an internal standard serum and presented a good linear fit with an R² =0.98. The coefficients of variation in the intra- and interassay precision tests were in the intervals established for each one (=10 percent, =20 percent respectively). The results obtained support the use of this quantitative ELISA for the evaluation of the immunogenicity of VME formulations of S. Paratyphi A in research and development phases(AU)

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