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Biomarcadores em Ucides cordatus (Linnaeus, 1763), desenvolvimento de bio-ontologia e aplicativo para monitoramento de impactos ambientais em regiões portuárias do Maranhão

2024-11-25T00:00:00Z

Título: Biomarcadores em Ucides cordatus (Linnaeus, 1763), desenvolvimento de bio-ontologia e aplicativo para monitoramento de impactos ambientais em regiões portuárias do Maranhão Abstact: This study aimed to use biomarkers in Ucides cordatus (Linnaeus, 1763) as a basis for the development of a bio-ontology and an application to monitor environmental impacts in port regions of Maranhão. In 2021, male specimens of U. cordatus (caranguejo-uçá) were captured quarterly in the mangroves of the Port Complex of São Luís - MA (through the bracing technique) at two different points: P1 located between two ports in the industrial region of São Luís (where there is an intense flow of small and large vessels, due to port and fishing activities); P2 which is close to an important fishing and tourist port in the region subject to human interference (effluents, solid waste and vessel engine oil). Biometric measurements were recorded from the specimens and the gills and hepatopancreas were extracted for histological analysis and enzyme activity (catalase – CAT and glutathione S-transferase – GST). Gills, hepatopancreas and edible tissue of the crabs were also collected for analysis of metals (Al, As, Cd, Cu, Cr, Fe, Pb, Mn, Ni and Zn). In the field, water and sediment samples were collected for analysis of the content of metals and other elements (Al, As, Cd, Cu, Cr, Pb, Hg, Mn, N, Ni, P and Zn). The results for the abiotic parameters showed values in accordance with the legislation for both areas. Al, P, Mn and Zn were found at levels above those permitted in the water. All elements found in the sediment were higher in P1. In general, the elements in the tissues were concentrated in the order: Fe>Al>Zn>Cu>Mn>Ni>Cr>Pb for point P1 and Al>Fe>Zn>Cu>Mn>Ni>Cr>Pb for point P2. Changes in CAT and GST activities were found in crabs from both areas, with the gills showing the highest activity (p < 0.05), as they were in direct contact with the contaminant (acute response). The results showed higher values of histological lesions in P1, but it was observed that the damage to the organ was similar between the areas. The lesions classified as irreversible were found in large numbers in organisms captured in P1, compromising the functioning of the organ and the health of the organisms residing in this region. More severe histological changes were observed in the hepatopancreas, with the organ best demonstrating the history of contamination. The biomarker information served as a basis for the construction of the bio-ontology with the biomonitor species. The evolution of the ontology has helped to connect concepts, facilitating the understanding of the stress of the estuarine environment where port activities are located. This reinforces the usefulness of the bio-ontology for environmental monitoring in port regions. The Crab Monitor software was created and will act to better share and access information, in a more effective approach to biomonitoring of port regions with native species. Based on the results obtained, it is concluded that the bio-ontology and the Crab Monitor software can assist in the continuous and predictive monitoring of port and industrial regions.

Estudo clínico-epidemiológico e laboratorial das arboviroses e associação com índices vetoriais em áreas endêmicas do estado do Maranhão, Brasil

2024-10-09T00:00:00Z

Título: Estudo clínico-epidemiológico e laboratorial das arboviroses e associação com índices vetoriais em áreas endêmicas do estado do Maranhão, Brasil Abstact: The main arboviral diseases registered in Brazil are dengue, chikungunya and zika, transmitted by the Aedes aegypti mosquito. They have similar symptoms, which makes accurate clinical diagnosis difficult. The objective was to conduct a clinical-epidemiological and laboratory study of arboviruses using molecular biology techniques and to associate the epidemiological aspects of arboviruses with vector indices of Aedes aegypti from endemic areas of Maranhão. Venous blood samples were collected from individuals with suspected arboviruses in the municipalities of Caxias, Codó, Peritoró, and São Mateus do Maranhão from January to July 2019 (Caxias) and from February to June 2022. Samples were subjected to RNA extraction and then tested by RT-qPCR to investigate infection by dengue (DENV-1 to 4), Zika (ZIKV), and Chikungunya (CHIKV) viruses. Positive samples were inoculated into cell culture to isolate the virus and increase the viral load for subsequent nucleotide sequencing. A total of 171 human samples were analyzed, of which 72 were positive, 68 (39.7%) from Caxias; two (2) (1.1%) from Codó; one (1) (0.6%) from Peritoró; and one (1) (0.6%) from São Mateus. A total of 58 positive samples (85.3%) corresponded to infections caused by DENV-1, 4 (5.9%) by DENV-2, one (1) (1.5%) by DENV-3 and in 6 (7.3%) samples, the presence of CHIKV was detected, being a co-infection caused by DENV-1 and CHIKV observed in Caxias. DENV-1 genotype V was detected in four samples analyzed and CHIKV ECSA genotype was detected in one sample. The largest number of human positive samples collected was obtained in Caxias, where DENV-1, DENV-2, DENV-3 and CHIKV were detected, confirming the circulation of these viruses in the interior of Maranhão. The characterization of positive patients showed that males, brown skin, aged 5 to 9 years, and residents of urban areas were the most affected by arboviruses. Fever was the most frequent symptom in both sexes, followed by headache in men and myalgia and nausea in women. The highest number of positive cases in Caxias was observed in Vila Paraíso, followed by Nova Caxias and Seriema peripheral neighborhoods of the city. DENV-3 was detected in the Vila São José neighborhood (Caxias-MA). There was a positive effect of LIRAa on the incidence of dengue (r2 = 0.0352; p = 0.0062) in Maranhão. All municipalities in the state that in any cycle of 2022 presented infestation rates of Ae. aegypti in a situation of alert or high risk, also exhibited high incidences of dengue or chikungunya. The research highlights the importance of carrying out more virological, entomological and epidemiological monitoring studies that provide an overview of the situation of arboviruses in areas where they are endemic and favor the development of effective preventive measures that effectively collaborate with the control and reduction of outbreaks and epidemics of these diseases.

Atividade antibacteriana de Ageratum conyzoides L. sobre microrganismos patogênicos in vitro

2025-08-28T00:00:00Z

Título: Atividade antibacteriana de Ageratum conyzoides L. sobre microrganismos patogênicos in vitro Abstact: The increasing problem of microbial resistance has intensified the search for new therapeutic alternatives from medicinal plants. Ageratum conyzoides L., popularly known as mentrasto, is highlighted for its bioactive compounds with recognized antimicrobial properties. This study evaluated the antibacterial potential of the essential oil, crude extract, and fractions of A. conyzoides L. against pathogenic microorganisms of public health importance, correlating chemical composition with biological activity. The essential oil was obtained by hydrodistillation, while the crude extract was prepared with solvents and fractionated, including the ethyl acetate fraction. Chemical characterization was performed using gas chromatography– mass spectrometry (GC-MS), which enabled the identification of major and minor compounds. Antimicrobial activity was assessed by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), using reference bacterial strains and comparing results with standard antibiotics. Cytotoxicity of the extracts and oil was also evaluated on RAW 264.7 murine macrophages through the MTT assay. The crude extract and especially the ethyl acetate fraction exhibited significant antibacterial effects, with MIC values consistent with relevant antimicrobial activity. GC-MS analysis revealed terpenes and flavonoids among the main metabolites, which likely contribute to the observed effects. The essential oil demonstrated a favorable safety profile, showing no significant cytotoxicity even at high concentrations (up to 1000 μg/mL). In conclusion, A. conyzoides L. represents a promising natural source of antimicrobial biomolecules with low cytotoxicity. The ethyl acetate fraction stood out as the most active, making it a strong candidate for further studies aiming at compound isolation and development of phytotherapeuti

Aspectos tróficos, ecológicos e moleculares como ferramenta de monitoramento da biodiversidade em um Complexo Portuário na Costa Amazônica Brasileira

2025-12-22T00:00:00Z

Título: Aspectos tróficos, ecológicos e moleculares como ferramenta de monitoramento da biodiversidade em um Complexo Portuário na Costa Amazônica Brasileira Abstact: This study aims to estimate biological diversity through morphological and eDNA analyzes in the water and sediment of the São Marcos Estuarine Complex (SMEC), a region of great importance on the Amazon coast due to its ecological and socioeconomic significance. Samples were collected between 2018 and 2023 during the rainy and dry seasons. The results obtained using traditional methods (plankton nets, gillnets, dredges and other capture equipment, as well as taxonomic and morphological analysis) revealed a biological diversity distributed among the kingdoms Eubacteria, Chromista, Plantae, and Animalia, registering approximately 289 taxa. ß-diversity analysis indicated that species replacement accounted for about 90% of the total variation in community composition. Environmental conditions showed significant variations, with greater heterogeneity recorded during the dry season and in the years 2020 and 2023, marked by atypical events. Through eDNA samples, it was possible to recover sequences for the Archaea, Bacteria, and Eukaryota domains, recording 39 eukaryotic phyla. The 18S marker showed the highest yield and captured a wide diversity of microeukaryotes, while COI, although less specific, contributed to the detection of metazoans. Based on phytoplankton identification, four potentially harmful species were found. Furthermore, ecological indices indicate low diversity and moderate species richness. Using the Multimetric Trophic Index (TRIX), it was possible to observe a eutrophic environment, with compromised water quality due to the high nutrient load caused by the discharge of domestic and industrial effluents from human activities. Regarding in silico evaluation, primers related to the 18S gene were designed to maximize organism identification. The developed primers were effective in identifying phytoplankton at the species level. The results highlight the importance of assessing the environment in an integrated way, especially in a highly dynamic, diverse system subject to intense degradation.