Entoepidemiology of Chagas disease in northwest São Paulo and cytogenetic analysis of its main vector, Triatoma sordida (Hemiptera: Triatominae).

One century after the discovery of Chagas disease, it is still considered as a major health problem, causing more deaths in the Americas than any other parasitic disease. The northwest region of São Paulo, a macro-region that includes cities with a high-quality of life, has particularly high rates of Chagas disease. Therefore, this study aimed to assess the number of patients with Chagas disease, and to identify the triatomine fauna in the northwest region of São Paulo State, and to cytogenetically analyze Triatoma sordida mutants, thus providing new knowledge to control these species and avoid possible infections by Chagas disease. A total of 700 Chagas patients of both genders and variable age, who were born in and residents of the northwest region of the State of São Paulo were recruited for this study. Regarding the entoepidemiological fauna, both T. sordida and Rhodnius neglectus were captured from 2004 to 2011 in the northwest region of the São Paulo; however, T. sordida was the predominant species. Some of these collected triatomines were infected by Trypanosoma cruzi in several developmental stages. Furthermore, the lactoacetic orcein method was used for cytogenetic analysis. Several abnormalities were observed during meiosis of the T. sordida mutants, including condensed chromosomes with no chiasma, chromatin bridges between the autosomes, and some non-pairing homologous chromosomes. Thus, our study suggests that Chagas disease is currently not under control in Brazil. Furthermore, we suggest that cryptic speciation may be occurring in populations of T. sordida of Brazil. Further studies are necessary to understand the mechanisms behind these phenomena.

Annexin A1 subcellular expression in laryngeal squamous cell carcinoma.

AIMS: Annexin A1 (ANXA1) is a soluble cytoplasmic protein, moving to membranes when calcium levels are elevated. ANXA1 has also been shown to move to the nucleus or outside the cells, depending on tyrosine-kinase signalling, thus interfering in cytoskeletal organization and cell differentiation, mostly in inflammatory and neoplastic processes. The aim was to investigate subcellular patterns of immunohistochemical expression of ANXA1 in neoplastic and non-neoplastic samples from patients with laryngeal squamous cell carcinomas (LSCC), to elucidate the role of ANXA1 in laryngeal carcinogenesis. METHODS AND RESULTS: Serial analysis of gene expression experiments detected reduced expression of ANXA1 gene in LSCC compared with the corresponding non-neoplastic margins. Quantitative polymerase chain reaction confirmed ANXA1 low expression in 15 LSCC and eight matched normal samples. Thus, we investigated subcellular patterns of immunohistochemical expression of ANXA1 in 241 paraffin-embedded samples from 95 patients with LSCC. The results showed ANXA1 down-regulation in dysplastic, tumourous and metastatic lesions and provided evidence for the progressive migration of ANXA1 from the nucleus towards the membrane during laryngeal tumorigenesis. CONCLUSIONS: ANXA1 dysregulation was observed early in laryngeal carcinogenesis, in intra-epithelial neoplasms; it was not found related to prognostic parameters, such as nodal metastases.