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PREVALÊNCIA E CARACTERIZAÇÃO DE HEMOGLOBINOPATIAS EM DOADORES DE SANGUE DO HEMOCENTRO DO MARANHÃO

Wed, 01 Jan 2025 00:00:00 GMT

Título: PREVALÊNCIA E CARACTERIZAÇÃO DE HEMOGLOBINOPATIAS EM DOADORES DE SANGUE DO HEMOCENTRO DO MARANHÃO Abstract: Hemoglobinopathies are the most prevalent group of monogenic diseases worldwide and represent a significant public health concern in Brazil, particularly in the North and Northeast regions, where African ancestry has a strong influence. This study aimed to estimate the prevalence and to qualitatively and quantitatively characterize hemoglobin variants in blood donors attended by the public blood transfusion network of Maranhão throughout the year 2023. A total of 88,064 unique samples were analyzed using hemoglobin electrophoresis (ELH), high-performance liquid chromatography (HPLC), and, in selected cases, molecular biology techniques. The overall prevalence of hemoglobinopathies was 4.09%, with the sickle cell trait (Hb AS, 3.28%) being the most common, followed by Hb AC (0.59%) and β-thalassemia (0.08%). Additionally, 36 samples with Hb Korle-Bu were identified, including one homozygous case, along with less frequent variants such as Hb D-Los Angeles, Hb Camperdown, Hb G-Philadelphia, Hb A2', Hb Hope, and Hb O-Arab. A total of 18 cases showed coherance between Hb S and alpha-thalassemia deletions. Statistical analysis revealed a significant association between blood center and phenotype (p < 0.05), with adjusted residuals indicating higher concentrations of variants in the municipalities of Codó, Caxias, and São Luís. The application of molecular methods was essential to confirm rare variants, clarify uncommon combinations, and support the reclassification of phenotypes with overlapping electrophoretic and chromatographic profiles. These findings highlight the importance of an integrated diagnostic approach, in which molecular biology serves as a complementary tool to phenotypic screening. The results contribute to transfusion safety, epidemiological surveillance, and the development of public health policies tailored to the genetic landscape of the Maranhão population, characterized by high heterogeneity and diverse ancestry. Keywords: Hemoglobinopathies; Blood donors; HPLC; Hemoglobin electrophoresis; Molecular diagnosis. Tipo: Dissertação

"O papel da via NRF2-ARE na adaptação redox celular durante crises vaso-oclusivas em pessoas com anemia falciforme. "

Wed, 01 Jan 2025 00:00:00 GMT

Título: "O papel da via NRF2-ARE na adaptação redox celular durante crises vaso-oclusivas em pessoas com anemia falciforme. " Abstract: Sickle cell anemia (SCA) is a disease that presents wide clinical heterogeneity. Studies aimed at identifying genetic and biochemical modulators have contributed to the understanding of the pathophysiological mechanisms of the disease. Among these mechanisms, chronic oxidative stress, resulting from the failure of antioxidant defense systems, plays a central role in the cellular damage observed. In this context, the NRF2-ARE pathway plays a fundamental role in regulating the expression of antioxidant genes essential for maintaining redox balance in the erythrocytic environment. Given this, the objective of this study was to investigate the contribution of the NRF2-ARE pathway in the redox adaptation of patients with AF under different conditions of pain crises in the last year before the start of the research, with patients without pain crises (SC, n=14), low frequency (BFC, n=7; 1 to 2 crises), and high frequency (AFC, n=4; more than six crises). Hematological analyses were performed, as well as an evaluation of the relative expression (qPCR) of the NFE2L2, SOD1, CAT, GPX1, TXNRD1, and GSR genes and the enzymatic activities of Cat, Gpx, Gr, GST, and G6PDH by spectrophotometry. The data were submitted to normality tests, univariate analyses (ANOVA or Kruskal-Wallis), correlations (Pearson or Spearman), and multivariate analysis (PLS-DA). Hematological characterization did not reveal statistically significant differences between the groups, although the AFC group showed a pattern of reduced hemoglobin and hematocrit. PLS-DA analysis demonstrated considerable overlap of hematological variables, gene expression, and enzyme activity between the groups evaluated. Among the genes studied, only SOD1 showed lower expression in the groups with higher seizure frequency (p Tipo: Dissertação

"Potencial de fungos filamentosos para promoção de crescimento vegetal sob condições de déficit hídrico. "

Wed, 01 Jan 2025 00:00:00 GMT

Título: "Potencial de fungos filamentosos para promoção de crescimento vegetal sob condições de déficit hídrico. " Abstract: The global average temperature has increased between 0.2 °C and 1.1 °C since 1850, a period associated with the Industrial Revolution. This variation, driven by climate change, has a significant impact on agriculture, intensifying abiotic stress. In this context, endophytic fungi have stood out for establishing mutualistic relationships with plants, providing benefits such as increased tolerance to abiotic stress. This study aimed to identify new drought-tolerant fungal isolates and evaluate their potential as plant growth promoters. The isolates were collected from rocky outcrops at Fazenda São João (Corumbá/MS), obtained from the roots of *Discocactus ferricola*. Fungal growth tests were conducted at different temperatures (30 °C, 35 °C, and 40 °C) and under water deficit conditions using PEG (-0.1 MPa, -0.2 MPa, and -0.4 MPa). After defining the parameters, the isolates were assessed for plant growth promotion, with and without PEG (-0.1 MPa). The analyzed fungi included *Penicillium* sp. (DF1 and DF5), *Aspergillus* sp. (DF2 and DF4), *Chaetomium* sp. (DF3), and *Trichoderma* sp. (T24 and GT31). All isolates grew at 30 °C and 35 °C and showed growth in BD medium with -0.1 MPa of PEG. Among the isolates, DF1 stood out for its ability to solubilize calcium and aluminum phosphates, both in the presence and absence of PEG. All isolates produced ACC deaminase (ACCD), with variations ranging from 18.46 ± 3.8 to 5.42 ± 2.4 μM of α-ketobutyrate h⁻¹ mg⁻¹ protein. Indole-3-acetic acid (IAA) production was observed in all tested fungi, with DF2 showing the highest concentration in the presence of PEG (53.99 ± 0.6 μg/mL). Regarding siderophore production, all isolates maintained consistent production, with DF1 exhibiting the highest values in both normal medium and PEG (-0.1 MPa). Enzymatic assays demonstrated that the isolates produce crucial enzymes for the carbon cycle. DF1 (*Penicillium* sp.) was selected for maize experiments conducted in a greenhouse under water stress conditions due to its relevant characteristics, including IAA production, siderophore synthesis, phosphate solubilization, ACC deaminase activity, and enzymes associated with nutrient cycling. Our results showed that DF1 contributed to plant defense strategies under water deficit conditions, promoting the accumulation of osmolytes such as total sugars, reducing sugars, and free amino acids for tissue protection and stimulating the production of antioxidant enzymes essential for mitigating damage caused by reactive oxygen species (ROS). Additionally, DF1 increased microbial activity in the soil, contributing to environmental health and fertility, as well as a more balanced nutrient cycle. Based on these findings, fungal isolates from predominantly rocky regions demonstrated significant potential in promoting plant growth under water stress conditions. Tipo: Dissertação

Potencial de Trichoderma spp na solubilização de fosfato e promoção de crescimento vegetal

Wed, 01 Jan 2025 00:00:00 GMT

Título: Potencial de Trichoderma spp na solubilização de fosfato e promoção de crescimento vegetal Abstract: Phosphorus is an essential element for plant growth and development; however, its limited availability, rapid immobilization, and leaching in the soil pose environmental and economic challenges. Plant growth-promoting fungi have the ability to solubilize phosphate complexed with other elements, produce phytohormones, and protect plants from phytopathogen attacks. These fungi can also synthesize enzymes, such as phosphatase and phytase, which aid in the mineralization of immobilized phosphate in organic molecules, making it more available to plants. Based on these aspects, the objective of this study was to optimize phosphate solubilization and evaluate plant growth-promoting characteristics in new Trichoderma isolates. Fungal growth was conducted in Pikovskaya medium with 0.5% phosphate fertilizers for 7 days at 28°C. After incubation, the inocula were filtered, and the supernatant was used for pH measurement and soluble phosphorus quantification. After selecting phosphate-solubilizing fungi, the following parameters were evaluated: solubilization time, phosphate sources, production of indole-3-acetic acid (IAA), siderophores, organic acids, and phosphatase and phytase enzymes. Finally, a greenhouse experiment was conducted to assess the plant growth-promoting effects of Trichoderma sp. G41 on corn (Zea mays ADV9339) seeds. Among the 22 fungi tested, Trichoderma sp. G41 proved to be the most promising, exhibiting phosphate solubilization of Ca3(PO4)2 (696.55 µg P mL-1), AlPO4 (421.98 µg P mL-1), and FePO4 (9.91 µg P mL-1) after 10 days of incubation. It also solubilized different commercial phosphate fertilizers, including thermophosphate tal qual (12.88 µg P mL-1), granulated thermophosphate (8.31 µg P mL-1), MV27 (169.66 µg P mL-1), and superphosphate (483.19 µg P mL-1). The fungus produced acid phosphatase (4.37 U mL-1) and phytase (1.51 U mL-1) enzymes, siderophores (74%), IAA (42.197 µg mL-1), organic acids, and exhibited growth tolerance in the presence of curbix (insecticide) and atrazine (herbicide). Trichoderma sp. G41 also maintained its phosphate-solubilizing capacity under stress conditions. In the presence of NaCl 150 mM, it reached 949.27 µg P mL-1, while at NaCl 300 mM, it solubilized 936.20 µg P mL-1. Under droght stress, it achieved 452.15 µg P mL-1 at -0.5 MPa and 498.27 µg P mL-1 at -1 MPa after 10 days of growth.In a greenhouse experiment with corn, treatments that received half the phosphate fertilizer dose and were inoculated with Trichoderma sp. G41 showed a 47% increase in root fresh matter and a 38% increase in shoot biomass. Inoculated plants exhibited higher chlorophyll, carotenoid, amino acid, and reducing sugar levels. Additionally, soil acid phosphatase and phytase activity increased in the presence of G41 under both fertilizer doses. Fluorescein diacetate hydrolysis indicated higher microbial activity in rhizospheric soil inoculated with the fungus. Based on these findings, Trichoderma sp. G41 demonstrated great potential as a phosphate-solubilizing agent, promoting corn growth and reducing the need for phosphate fertilizers. Thus, it stands out as a sustainable alternative for improving soil quality and enhancing agricultural efficiency. Tipo: Dissertação