ABSTRACT
Abstract Chagas disease (CD) is caused by the protozoan Trypanosoma cruzi and affects about six to seven million individuals worldwide. The distribution of cases is concentrated mainly throughout Latin America, especially in rural areas. This study aims to evaluate microRNAs (miRNAs) as indicators in CD diagnosis for possible contributions to its management. This is a literature review study, carried out in the PubMed, SciELO, Bireme Library, NCBI, Science Direct, and Embase databases, through which a total of 12 articles were included for qualitative analysis. The discussion of this review was based on the thematic axes regarding the modulation of T. cruzi in the immune system and the expression of miRNAs, their production and action, the modulation mechanism of host gene expression, how they act as biomarkers, the importance of miRNAs in the diagnosis of CD, and how their regulation occurs in Chronic Chagas Cardiomyopathy (CCC). Moreover, T. cruzi infection is associated with the downregulation of several miRNAs, which directly related to the findings of hypertrophy and fibrosis. When quantified, these could be used as consistent indicators for CD to support the diagnosis of patients with CD complications, as well as a possible therapeutic target. However, the need for clinical studies that evaluate the usefulness of this biomarker in humans is emphasized, considering that in the present study, only experimental in vitro studies were evaluated, reflecting a lack of studies with practical applicability.
ABSTRACT
A cirurgia de redução de volume pulmonar (CRVP) é um tratamento paliativo utilizado em doentes com enfisema grave que visa melhorar a função pulmonar e a qualidade de vida, através da remoção do tecido fibrosado resultante do enfisema. Esta intervenção promove uma expansão adequada dos pulmões na caixa torácica, melhorando o recoil elástico e a relação ventilação/perfusão devido à diminuição da hiperinsuflação pulmonar. Foi objetivo do presente artigo de revisão caracterizar os efeitos da CRVP no enfisema no respeitante à melhoria da função pulmonar. Foram considerados artigos publicados em periódicos indexados nas bases de dados MEDLINE, SciELO, Latindex e DOAJ. Foram incluídos 25 documentos que abrangem artigos originais e artigos de revisão de literatura. A CRVP promove uma melhoria dos parâmetros avaliados por espirometria e pletismografia corporal total, devido ao aumento do recoil elástico promovido pela redução dos volumes pulmonares não mobilizáveis (redução da hiperinsuflação pulmonar), pelo reposicionamento dos músculos respiratórios e pela diminuição da resistência das vias aéreas. Contudo, diversas investigações demonstraram que os efeitos na função pulmonar são temporários e reversíveis. Fatores como a elevada taxa de morbilidade e mortalidade e o custo elevado relativamente à durabilidade dos benefícios que este procedimento acarreta estão na base das opiniões controversas relativas à CRVP. A CRVP não modifica o curso natural da doença, sendo por isso necessário avaliar a vertente económica deste procedimento bem como a sua relação custo-benefício, isto porque este tratamento se tem demonstrado dispendioso face à durabilidade dos benefícios.
Lung volume reduction surgery (LVRS) is a palliative treatment used in patients with severe emphysema that aims to improve lung function and quality of life by removing the fibrous tissue resulting from emphysema. This intervention promotes an adequate expansion of the lungs in the chest cavity, thus improving the elastic recoil and ventilation/perfusion ratio due to decrease of lung hyperinflation. The aim of this review article is to characterize, the effects of LVRS in emphysema in relation to the improvement in lung function. We considered articles published in journals indexed in MEDLINE , SciELO , Latindex and DOAJ. We included 25 documents covering original articles and literature review articles. LVRS promotes the improvement of the spirometry and whole body plethymography parameters, caused by the increase of elastic recoil through the reduction of not mobilized lung volumes (lung hyperinflation reduction), the repositioning of the respiratory muscles and the decrease of airways resistance. However, several investigations have shown that the effects on lung function are temporary and reversible. Factors such as the high morbidity and mortality rates and the high cost in relation to the durability of the benefits of the procedure lead to controversial opinions about LVRS. LVRS does not modify the natural course of the disease, so it is necessary to evaluate the economic aspect of this procedure and its cost-effectiveness, because this treatment is considered expensive comparatively to the durability of benefits.