Anais da Academia Brasileira de Ciencias最新文献

Leaf litter is an important component related to nutrient cycling and conservation of soil biodiversity. In this context, the objective of our study was to investigate the relationship between soil and leaf litter in different forest communities in sub-regions of the Pantanal (Nhecolândia and Abobral/Miranda). To this end, we collected soil and leaf litter samples from 152 sample plots divided in physiognomies regionally called as Cordilheira, Capão, Murundu, Corixo and Cambará/Canjiqueira forest. In the laboratory, analytical determinations were conducted for 22 soil attributes and 11 elements of the chemical composition of the leaf litter. The forest communities showed a great well-defined edaphic gradient encompassing environments with high natural fertility soils (Capão and Cordilheira Abobral/Miranda), acidic soils with a high proportion of soluble Al3+ (Cambará/Canjiqueira, and Corixo), and poorly developed soils with a predominantly sandy texture (Nhecolândia region, Cordilheira and Murundu). Soil attributes are significantly related to the chemical composition of litter, as indicated by correlations between N, P, Ca, Mg, Mn and the C/N ratio with physical, chemical and soil organic matter attributes. This study revealed the interaction of soils with the chemical composition of litter, constituting an ecosystem service, in forest communities in the Brazilian Pantanal.

Aiming to verify whether the diversity of secretory structures with their respective exudates are or not responsible for the attendance of floral visitors in Miconia species, the floral secretory structures of two Amazonian species of Miconia were described and interpreted from the functional perspectives and observations of floral visitors. Flowers and floral visitors were collected in the field for 16 months. The flowers were subjected to standard anatomical analyzes using light and scanning electron microscopy, and the secretory structures were evaluated using histochemical tests. The insects were photographed, collected and identified by a specialist. Floral secretory structures (stigmatic papillae and trichomes at the apex of the ovary) were found in M. alata and M. ciliata. Trichomes were found at the hypanthium of M. alata, and of the sepals and receptacles in M. ciliata. In both species, different hydrophilic compounds were detected in the exudates. Only phenolic compounds were found in the trichomes of the M. ciliata receptacle. This study provides information that confirms the hypothesis that other secretory structures and exudates are related to floral visitors, and adds new informations about the features of the secretory structures in Miconia.

Food drying is still a crucial step in the food manufacturing process for food preservation, and the foam-mat drying method can be utilized to further enhance food preservation. This study aims to develop an instant L. powder enriched with Moringa oleifera L. extract and to evaluate the effect of foam mat drying conditions on physicochemical and antioxidant properties.The experimental design used a factorial completely randomized block design (FCBD), with triplicates. Based on the results showed that the interaction between the different forms of moringa extract, when added, and drying temperature affected color, water activity, bulk density, hygroscopicity, total acid titration, moisture content, ABTS, antioxidant activity and total flavonoid contents (p<0.05) but did not affect solubility, total soluble solids, flow rate, pH, DPPH antioxidant activity and total phenolic contents (p>0.05). Samples dried at a temperature of 70°C (T3), both liquid (F1) and microencapsulated (F2), exhibited the best physicochemical and antioxidant properties. These findings confirmed the suitability of foam mat drying to produce P. angulata instant powder enriched with M. oleifera extract for functional food ingredients.

The COVID-19 pandemic has been the largest pandemic of the past century, and various genetic factors have played a significant role in this context. This study aimed to analyze the frequency and association between specific SNPs rs3806268 (NLRP3), rs4925543 (NLRP3), rs12150220 (NLRP1), rs455060 (NLRC4), rs699 (AGT), rs1137101 (LEPR), and rs1801133 (MTHFR) and severe/critical outcomes in Brazilian patients with COVID-19. A total of 100 patients were included in the study, comprising 66 cases and 34 controls. DNA was extracted, sequenced, and genotyped via next-generation sequencing (NGS). For non-parametric data, the Mann-Whitney and Kruskal-Wallis tests were used. Fisher's test and multivariate logistic regression, considering AIC and BIC criteria, were employed for risk analysis. Odds Ratios (OR) were calculated, with significance set at p<0.05. Among the seven evaluated SNPs, only rs699-GG (AGT) (OR=8.07; p=0.04) was significantly associated with an increased risk of developing severe/critical COVID-19. Moreover, a borderline protective association was noted between rs1801133-GA (MTHFR) and the disease, although lacking statistical significance. In conclusion, the SNP rs699-GG (AGT) was associated with an increased risk of severe/critical COVID-19.

Dinizia Excelsa is an Amazonian tree with a wide range of applications as a raw material in the industry. The objective of this study was to extract, characterize, and evaluate the biological activities of xylan extracted from Dinizia excelsa wood. The xylan was obtained in five stages, including delignification, precipitation, purification, and freeze-drying. The physicochemical analysis of xylan included the determination of monosaccharides, elemental composition, FTIR analysis, 2D nuclear magnetic resonance spectroscopy, and the determination of molecular weight. Xylan had an extraction yield of 28.44% and an elemental composition of 35.03% carbon, 5.65% hydrogen, and 59.32% oxygen. FTIR analysis revealed similarities between Dinizia excelsa xylan and commercial xylan. 2D NMR analysis confirmed the presence of characteristic xylan groups. Furthermore, xylan has a low molecular weight. In vitro cytotoxicity tests demonstrated low toxicity, indicating its potential for biological applications. Immunomodulatory activity assays revealed that xylan stimulated cell proliferation and the production of anti-inflammatory cytokines. The anticoagulant activity of xylan was low compared to heparin. The antioxidant activity of xylan was weaker compared to ascorbic acid and butylated hydroxytoluene (BHT). These results indicate that xylan from Dinizia excelsa has potential for several biomedical applications due to its immunomodulatory and anticoagulant properties.

The therapeutic arsenal for veterinary pharmacotherapy includes both medicines for exclusive veterinary use and human medicines prescribed off-label for animals. Unlike medicines for exclusive veterinary use, the package inserts of human medicines detail the qualitative composition of the excipients in these products. Some excipients may cause adverse reactions in specific animal populations, necessitating that healthcare professionals identify and avoid administering medicines containing these excipients to susceptible animals. In this study, we analyzed 120 package inserts for human medicines prescribed for animals and, identified 14 excipients of concern for this population: 10 in liquid products, 6 in semi-solid products, and 5 in solid products. The identified excipients include ethyl alcohol, benzyl alcohol, benzalkonium chloride, mannitol, sodium metabisulfite, sodium lauryl sulfate, propylene glycol, polyethylene glycol, polysorbate, and ethoxylated castor oil. Although off-label use of human medicines in veterinary practice is permitted, the study suggests that regulatory agencies and professional councils should raise awareness among veterinary prescribers and pharmacists regarding these excipients. This unprecedented study highlights the urgent need to address this issue, aiming to encourage research on excipient safety in animal populations and strengthen veterinary pharmacovigilance services.

Melissopalynological techniques are used in the analysis of pollen grains. However, the adoption of methodologies considering cost-effectiveness, shorter preparation time and lesser toxic procedures for researchers is relevant. Thus, this study aimed to analyze different melissopalynological methodologies in polyfloral honey samples. Three melissopalynological protocols were applied to the samples using alcian blue dye, basic fuchsin, and the traditional acetolysis methodology without dye. After preparing the pollen samples, and analyzing them under an optical microscope, six botanical families were recorded, e.g., Amaranthaceae, Asteraceae, Bignoniaceae, Fabaceae, Malvaceae, and Myrtaceae. The methodologies investigated proved to be efficient for detecting pollen structures and identifying botanical families thereof. The alcian blue dye-based protocol allowed a greater separation and discrimination of pollen grains as compared to the basic fuchsin and acetolysis ones, where pollen conglomerates were often identified. Even though acetolysis has been the most used method in melissopalynological studies, it has been claimed to offer risks to users due to the manipulation of corrosive and toxic solvents (i.e., H2SO4), also being lesser cost-effective and more time-consuming. Thus, considering the cost-effectiveness, the alcian blue dye and basic fuchsin-based methods seem to be preferred, being as efficient as acetolysis for identifying pollen grains.

Fungi are the most important entomopathogens in the natural regulation of insect populations. They have a wide distribution and significant advantages as biological control agents. Prospecting for new native strains of entomopathogenic fungi in the Pampas region has not yet been carried out. The main objectives of this study were isolating and identifying strains of different species of entomopathogenic fungi that naturally infect grasshopper species in the Pampas region and determining, through laboratory tests, their virulence and pathogenicity on nymphs of the pest grasshopper Dichroplus maculipennis. Furthermore, whether the phylogenetic relationships between Beauveria bassiana isolates would be associated with virulence and pathogenicity or geographical distribution. Thirty-four isolates of entomopathogenic fungi were obtained from different grasshopper species corresponding to eleven sites in three counties in the center of Buenos Aires province. There were 31 isolates of B. bassiana and 3 of Metarhizium genus. These isolates scored 66.6% (LPSc 1443) and 100% (LPSc 1441, LPSc 1445, and LPSc 1476) of mortality against third-instar nymphs of D. maculipennis, and these last cause death at 4.86 ± 0.20, 4.80 ± 0.17 and 5 ± 0.15 MST days, respectively. An association between phylogenetic relationships and geographical distances in B. bassiana was found.

The present study aimed to inventory the parasitic fauna of Leporinus piau from the Lima Campos weir, Salgado River basin, municipality of Icó, Ceará, Brazil. A total of 35 host specimens were collected, whereas all were parasitized by at least two metazoan taxa. A total of 2,910 parasite specimens belonging to five taxonomic groups were identified such as: Myxozoa (Henneguya sp. 1 and Henneguya sp. 2), Monogenea (Jainus beccus, Jainus radixelongatus, Tereancistrum flabellum, Tereancistrum paranaensis, Tereancistrum parvus, Urocleidoides digitabulum, Urocleidoides paradoxus, Urocleidoides sp., Dactylogyridae gen. sp. 1, Dactylogyridae gen. sp. 2 and Dactylogyridae gen. sp. 3), Digenea (Diplostomum lunaschiae and Clinostomum sp.), Nematoda (Procamallanus (Spirocamallanus) inopinatus) and Copepoda (Gamispatulus schizodontis). Seventeen parasite taxa were found, with the class Monogenea being the most abundant group. The main site of infestation was the gills, presenting 14 taxa, including myxozoans, monogeneans and digeneans. This study highlights seven new parasitic associations for the host and 16 for the studied locality, as well as new records of diversity indices for the parasitic taxa found. It was observed that the class Monogenea exhibited a broad diversity of species, contributing to the understanding of the distribution patterns of fish parasites in the Brazilian semiarid region.