Paracoccidioidomycosis in the northern region of Rio Grande do Sul

Background and Objectives: Paracoccidioidomycosis (PCM) is a systemic disease caused by the dimorphic fungus Paracoccidioides brasiliensis found in the tropical and subtropical regions of Latin America. This study aimed to perform a retrospective analysis of PCM cases from the northern region of Rio Grande do Sul, Brazil. Methods: A total of 200 records of PCM cases from 1995 to 2015 were analyzed, diagnosed at the local reference pathology laboratory. Results: Of the patients, 185 were male and 15 female. Patients ranged in age from 31 to 80 years, the largest proportion (35,5%) being aged between 51 and 60 years and living or working in the countryside. Clinical samples were mostly obtained from the oral cavity, followed by the oropharynx, lungs, brain, skin, and prostate. Conclusion: PCM is endemic in the south of Brazil, as the local economy is largely based on agricultural activities, favoring the contact of the population with P. brasiliensis. Due to the great similarity between PCM symptoms and other respiratory diseases, the differential diagnosis is essential for the correct treatment of the disease and to avoid its progression

Serum from animals subjected to severe sepsis or experimentally infected with Trypanosoma cruzi induces dystrophin loss in cardiomyocytes cultured: role of calpain activation and blocked

O complexo distrofina-glicoproteínas associadas (DGC) localiza-se no sarcolema das células musculares esqueléticas e cardíacas e tem como função principal proporcionar ligação mecânica entre o citoesqueleto intracelular e a matriz extracelular. Estudos prévios realizados em nosso laboratório, focalizando o complexo DGC, demonstraram perda de proteínas importantes desse complexo. As situações avaliadas anteriormente foram: infecção experimental por Trypanosoma cruzi (T. cruzi) e sépsis experimental. Em ambas as situações verificou-se a perda da distrofina acompanhada por disfunção contrátil e aumento nos níveis da calpaína, protease dependente de cálcio implicada na proteólise da distrofina. Todavia, o mecanismo responsável pela ativação das calpaínas e proteólise da distrofina na infecção experimental por T. cruzi e na sépsis experimental não está totalmente definido. O objetivo desse trabalho foi avaliar in vitro o mecanismo responsável pela ativação das calpaínas nas culturas de cardiomiócitos desafiadas com o soro dos animais infectados experimentalmente com T. cruzi ou com o soro dos animais submetidos à sépsis grave experimental. Camundongos C57BL/6 foram submetidos à sépsis grave ou infectados com a cepa Y de T. cruzi. No pico de expressão das citocinas pró-inflamatórias, 12 dias após inoculação do parasito ou 6 horas após a indução da sépsis, o sangue foi coletado e o soro separado. Corações de camundongos recém-nascidos foram isolados para o cultivo dos cardiomiócitos. No quinto dia após o início das culturas, as células foram estimuladas com 10% do soro de animais infectados com T. cruzi ou o soro de animais submetidos à sépsis grave durante 24 horas. Após, as células foram coletadas para análises de Western blotting e imunofluorescência para verificar a expressão da distrofina e calpaína-1. Avaliou-se também, por imunofluorescência, a expressão do NF-B. Os cardiomiócitos foram estimulados e tratados com o dantrolene, inibidor da liberação de cálcio do retículo sarcoplasmático, ou ALLN, inibidor da calpaína-1, e após coletados para verificar a expressão da distrofina e calpaína-1 por Western blotting e imunofluorescência. Nossos resultados mostraram uma redução significativa na expressão da distrofina com desarranjo das miofibrilas contráteis e formação de bolhas citoplasmáticas, além de um aumento nos níveis da calpaína-1 e do NF-B. O tratamento com dantrolene nas culturas estimuladas com o soro de animais infectados experimentalmente com T. cruzi ou com o soro dos animais submetidos à sépsis grave, recuperou a expressão da distrofina e reduziu os níveis da calpaína-1. O tratamento com ALLN nos cardiomiócitos estimulados com o soro de animais infectados experimentalmente com T. cruzi recuperou a expressão da distrofina e não alterou os níveis da calpaína-1. Nas culturas estimuladas com o soro dos animais submetidos à sépsis grave, o tratamento com o ALLN recuperou a expressão da distrofina e reduziu os níveis da calpaína-1. Nossos resultados demonstraram que citocinas pró-inflamatórias presentes no soro dos animais infectados experimentalmente com T. cruzi como também no soro dos animais submetidos à sépsis grave induziriam um aumento no influxo de cálcio com consequente ativação das calpaínas, as quais atuariam na ativação do NF-B e na degradação da distrofina. Esse mecanismo poderia ser responsável pela proteólise da distrofina cardíaca observada na infecção experimental por Trypanosoma cruzi como também sépsis experimental. Mais estudos são necessários para elucidar este mecanismo, principalmente em relação a inibidores dos canais de cálcio, das citocinas pró-inflamatórias e das calpaínas, com o objetivo de fornecer novas vias de intervenção na prevenção de alterações cardíacas observadas na doença de Chagas e na sépsis.The dystrophin-glycoprotein complex (DGC), located in the sarcolemma of cardiac and skeletal muscle cells and concentrated along the plasma membrane in costameric structures provides a framework that connects the intracellular cytoskeleton to the extracellular matrix. Previous studies from our laboratory clearly demonstrated disruption of DGC proteins in experimentally-induced T. cruzi infection and experimental sepsis. Both situation presented dystrophin disruption associated with contractile dysfunction and increased calpain levels, calcium dependent protease responsible for dystrophin proteolysis. However, the mechanism responsible for calpain activation and dystrophin proteolysis in experimentally-induced T. cruzi infection and experimental sepsis is not totally understood. The aim of this study was to evaluate in vitro the mechanism responsible for calpain activation in cultured cardiomyocytes challenged with serum from animals experimentally infected with T. cruzi or subjected to severe sepsis. Mice C57BL/6 were subjected to sepsis induction or infected with Y strain from T. cruzi. At the peak of proinflammatory cytokines expression, 12 days after parasite inoculation or 6 hours after sepsis induction, the blood was collected and the serum separated. Hearts from newborn mice were isolated for culture of cardiomyocytes. After 5 days of incubation, the cardiac cells were stimulated with 10% of serum from animals experimentally infected with T. cruzi or subjected to severe sepsis during 24 hours, and collected for Western blotting and immunofluorescence analysis to verify dystrophin and calpain-1 expression. The expression of NF-B was evaluated by immunofluorescence. The treatments with dantrolene, inhibitor of calcium release from sarcoplasmic reticulum, or ALLN, calpain-1 inhibitor, were performed in cultured cardiomyocytes stimulated during 24 hours with serum from animals infected with T. cruzi or subjected to severe sepsis, and dystrophin and calpain-1 expression were analyzed by Western blotting and immunofluorescence. Our results demonstrated loss of dystrophin associated with myofibers derangement and presence of cytoplasmic blebs as well increase of calpain-1 and NF-B expression. The dantrolene treatment in cultures stimulated with serum from animals infected with T. cruzi or subjected to severe sepsis recovey dystrophin expression and reduced calpain-1 levels. The ALLN treatment in cardiomyocytes stimulated with serum from animals infected with T. cruzi recovery dystrophin expression and preserved calpain-1 levels. In cultures stimulated with serum from animals subjected to severe sepsis, the ALLN treatment recovery dystrophin expression and decreased calpain-1 levels. Our results demonstrated that proinflammatory cytokines in serum from mice infected with T. cruzi or subjected to severe sepsis could induce an increase calcium influx with calpain activation, which could act in NF-B activation and dystrophin disruption. Possibly, this mechanism could be responsible to dystrophin proteolysis observed in experimentally-induced acute T. cruzi infection and experimental sepsis. More studies are needed to elucidate this mechanism, especially in relation to calcium channel blockers and inhibitors of pro-inflammatory cytokines and calpains, which may provide new routes for intervention to prevent cardiac damage in Chagas disease and sepsis

Relevant aspects of golden retriever muscular dystrophy for the study of Duchenne muscular dystrophy in humans

ABSTRACT: Golden Retriever muscular dystrophy (GRMD) is the most representative model for studying Duchenne muscular dystrophy (DMD) in humans, owing its phenotypic expression. DMD is a recessive disorder linked to the X chromosome in which the loss of dystrophin induces progressive weakness and degeneration of the skeletal and cardiac muscles, which lead to replacement by connective and adipose tissues. Onset of clinical signs occurs between 2 and 5 years of age, and many patients die from heart or respiratory failure. The main studies concerning dystrophic Golden Retrievers (DGR) sought to elucidate the pathophysiology of the disease and its clinical implications to develop therapies and alternative treatments to improve the quality of life and increase longevity of DMD patients. This review presents an overview of relevant contributions of the DGR model for elucidating DMD in humans

Disruption of calcium homeostasis in cardiomyocytes underlies cardiac structural and functional changes in severe sepsis

Submitted by Jaqueline Silva ([email protected]) on 2019-01-23T16:37:10Z No. of bitstreams: 2 Artigo - Mara Rúbia Nunes Celes - 2013.PDF: 3514413 bytes, checksum: 678a726640bb848b312dd2454117a7bb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Luciana Ferreira ([email protected]) on 2019-01-24T11:20:55Z (GMT) No. of bitstreams: 2 Artigo - Mara Rúbia Nunes Celes - 2013.PDF: 3514413 bytes, checksum: 678a726640bb848b312dd2454117a7bb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Made available in DSpace on 2019-01-24T11:20:55Z (GMT). No. of bitstreams: 2 Artigo - Mara Rúbia Nunes Celes - 2013.PDF: 3514413 bytes, checksum: 678a726640bb848b312dd2454117a7bb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2013-07-23Sepsis, a major cause of morbidity/mortality in intensive care units worldwide, is commonly associated with cardiac dysfunction, which worsens the prognosis dramatically for patients. Although in recent years the concept of septic cardiomyopathy has evolved, the importance of myocardial structural alterations in sepsis has not been fully explored. This study offers novel and mechanistic data to clarify subcellular events that occur in the pathogenesis of septic cardiomyopathy and myocardial dysfunction in severe sepsis. Cultured neonatal mice cardiomyocytes subjected to serum obtained from mice with severe sepsis presented striking increment of [Ca2+]i and calpain-1 levels associated with decreased expression of dystrophin and disruption and derangement of F-actin filaments and cytoplasmic bleb formation. Severe sepsis induced in mice led to an increased expression of calpain-1 in cardiomyocytes. Moreover, decreased myocardial amounts of dystrophin, sarcomeric actin, and myosin heavy chain were observed in septic hearts associated with depressed cardiac contractile dysfunction and a very low survival rate. Actin and myosin from the sarcomere are first disassembled by calpain and then ubiquitinated and degraded by proteasome or sequestered inside specialized vacuoles called autophagosomes, delivered to the lysosome for degradation forming autophagolysosomes. Verapamil and dantrolene prevented the increase of calpain-1 levels and preserved dystrophin, actin, and myosin loss/reduction as well cardiac contractile dysfunction associated with strikingly improved survival rate. These abnormal parameters emerge as therapeutic targets, which modulation may provide beneficial effects on future vascular outcomes and mortality in sepsis. Further studies are needed to shed light on this mechanism, mainly regarding specific calpain inhibitors