CISTATINA C COMO MARCADOR DA FUNÇÃO RENAL NA NEFRITE LÚPICA

Complicações renais em portadores de lúpus eritematoso sistêmico são bastante comuns e tendem a piorar o prognóstico desses pacientes. Como a taxa de filtração glomerular é o principal indicador da função renal, é importante que seja estabelecido qual seria o marcador mais efetivo dela em pacientes com nefrite lúpica. O uso da cistatina C é considerado bastante promissor pela comunidade científica. Este trabalho tem, como finalidade, avaliar a utilização dessa substância como possível marcador nos portadores de nefrite lúpica. Foi realizada busca de artigos nos bancos de dados “ScieLO” e “PubMed”, utilizando descritores cadastrados nos Descritores em Ciências da Saúde (DeCS). Os artigos usados foram inconclusivos sobre o uso da cistatina C como biomarcador nessa população específica, devido a uma suposta influência que possa sofrer com o uso de glicocorticoides. No entanto, apontam que, em geral, a cistatina C tem características ideais para um marcador endógeno. Já a creatinina, o marcador endógeno mais utilizado, ainda é considerado referência, devido ao seu custo menor e ser mais conhecida, o que facilita a correção de suas falhas. Apesar da cistatina C ser considerada tão ou mais eficaz na avaliação da função renal que a creatinina, a sua utilização em pacientes com nefrite lúpica não pode ser recomendada em substituição aos outros marcadores disponíveis, uma vez que pode sofrer influência de glicocorticoides, tratamento utilizado nesses pacientes

First evidence of gonadal hybrid dysgenesis in Chagas disease vectors (Hemiptera, Triatominae): gonad atrophy prevents events of interspecific gene flow and introgression

Abstract Background Hybridization events between Triatoma spp. have been observed under both natural and laboratory conditions. The ability to produce hybrids can influence different aspects of the parent species, and may even result in events of introgression, speciation and extinction. Hybrid sterility is caused by unviable gametes (due to errors in chromosomal pairing [meiosis]) or by gonadal dysgenesis (GD). All of the triatomine hybrids analyzed so far have not presented GD. We describe here for the first time GD events in triatomine hybrids and highlight these taxonomic and evolutionary implications of these events. Methods Reciprocal experimental crosses were performed between Triatoma longipennis and Triatoma mopan. Intercrosses were also performed between the hybrids, and backcrosses were performed between the hybrids and the parent species. In addition, morphological and cytological analyzes were performed on the atrophied gonads of the hybrids. Results Hybrids were obtained only for the crosses T. mopan♀ × T. longipennis♂. Intercrosses and backcrosses did not result in offspring. Morphological analyses of the male gonads of the hybrids confirmed that the phenomenon that resulted in sterility of the hybrid was bilateral GD (the gonads of the hybrids were completely atrophied). Cytological analyses of the testes of the hybrids also confirmed GD, with no germ cells observed (only somatic cells, which make up the peritoneal sheath). Conclusions The observations made during this study allowed us to characterize, for the first time, GD in triatomines and demonstrated that gametogenesis does not occur in atrophied gonads. The characterization of GD in male hybrids resulting from the crossing of T. mopan♀ × T. longipennis♂ highlights the importance of evaluating both the morphology and the cytology of the gonads to confirm which event resulted in the sterility of the hybrid: GD (which results in no gamete production) or meiotic errors (which results in non-viable gametes). Graphical Abstrac

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field