Anais da Academia Brasileira de Ciencias最新文献

The Irati Formation (Paraná Basin) is a mixed carbonate and organic-rich shale sequence intruded by Jurassic-Cretaceous basic rocks, featuring Brazil's most important oil shale deposits with different maturity levels. For the first time, the distribution of oil shale biomarkers from an outcrop section (quarry) of the Irati Formation in the northernmost Paraná Basin was analyzed by GC-MS and GC-MS/MS to determine the thermal evolution, organic matter origin and the depositional paleoenvironment. The organic-rich shale at the northernmost border of the basin has high similarity with the central and southernmost areas, indicating a primary control able to induce cyclic sedimentation in a broad (106 km2) and restricted environment. PCA and HCA analysis of bulk and molecular parameters showed changes in the organic matter composition and paleoenvironmental conditions throughout the stratigraphic column. Nonetheless, there are significant differences compared to the central-eastern and southern areas of the basin. Contrasting with the southern region, the north, predominates biphytane, low and medium gammacerane index. Pr/n-C17, Ph/n-C18, HI and OI values suggest type II/III kerogen from marine organic matter with freshwater input. Among the steranes, those of stereochemistry ααα 20R predominate over ααα 20S, and the presence of βTm indicates the shales are less thermally evolved.

Sahelanthropus tchadensis has raised much debate since its initial discovery in Chad in 2001, given its controversial classification as the earliest representative of the hominin lineage. This debate extends beyond the phylogenetic position of the species, and includes several aspects of its habitual behavior, especially in what regards its locomotion. The combination of ancestral and derived traits observed in the fossils associated with the species has been used to defend different hypotheses related to its relationship to hominins. Here, the cranial morphology of Sahelanthropus tchadensis was assessed through 16 linear craniometric measurements, and compared to great apes and hominins through Principal Component Analysis based on size and shape and shape information alone. The results show that S. tchadensis share stronger morphological affinities with hominins than with apes for both the analysis that include size information and the one that evaluates shape alone. Since TM 266-01-060-1 shows a strong morphological affinity with the remaining hominins represented in the analysis, our results support the initial interpretations that S. tchadensis represents an early specimen of our lineage or a stem basal lineage more closely related to hominins than to Panini.

The littoral zone is an essential compartment for lake biota because of its high productivity and diversity. Moreover, phytoplankton is expected to have non-equilibrium dynamics on it. The study's aimed to explore phytoplankton in the littoral zone of a shallow lake over a short-term scale. Daily sampling was conducted for 25 consecutive summer days in 2016, at two marginal points of a continuously warm, polymictic, and oligo-mesotrophic subtropical lake (Lake Mangueira, Brazil). Cyanobacteria and Chlorophyta contributed 86% of total biomass. We observed high variability in phytoplankton structure, with species turnover over diel cycles. Redundancy analysis indicated spatial differentiation for phytoplankton structure in relation to abiotic conditions. Nutrient dynamics and humic substances were significant drivers for phytoplankton variability. Phytoplankton was positively correlated with SRP and negatively with humic substances. Our results showed a non- equilibrium state for the littoral phytoplankton of Lake Mangueira, given the high variability of abiotic conditions, even at short distances. Due to its high temporal and spatial variability, the littoralzone seems to contribute to the recruitment and maintenance of phytoplankton biodiversity in shallow lakes. Further studies should consider the functional attributes of species and the complex biological interactions of phytoplankton and macrophytes along the littoral zone.

Klebsiella pneumoniae (K. pneumoniae) is a major cause of healthcare-associated infections and plays a prominent role in the widespread antibiotic resistance crisis. Accurate identification of carbapenemases is essential to facilitate effective antibiotic treatment and reduce transmission of K. pneumoniae. This study aimed to detect carbapenemase production in carbapenem-resistant K. pneumoniae strains using phenotypic and genotypic methods. A total of 67 carbapenem-resistant K. pneumoniae strains obtained from various clinical samples were utilized for identification and antimicrobial susceptibility by the Vitek 2 Compact system (Biomerieux, France). Carbapenemase production was determined by using the Polymerase chain reaction, Blue-carba test (BCT) and Carbapenem inactivation method (CIM). Out of the isolates, 59 (88.1%) were positive bla OXA-48, 16 (23.9%) bla IMP, and five (7.5%) were positive bla NDM. No bla KPC genes were detected. The CIM identified 62 (92.5%), BCT identified 63 (94%) of PCR-positive isolates. The sensitivity and specificity of the BCT and the CIM were determined to be 96.7%, 40%, and 96.7%, 25% respectively. The bla OXA-48 gene was found to be the most prevalent in K. pneumoniae isolates. Early identification of carbapenem resistance plays a vital role in designing effective infection control strategies and mitigating the emergence and transmission of carbapenem resistance, thus reducing healthcare-associated infections.

Detection of Salmonella sp. is important for the broiler chicken production chain because it is one microorganisms involved in food-borne diseases. Thus, this study performed the optimization of a technique of Loop-mediated isothermal DNA amplification (LAMP) through the 3MTM Molecular Detection Assay 2: Salmonella (MDS®), in accordance with Ordinance number 126 of the Ministry of Agriculture, for the detection of Salmonella sp. in drag swab. The methodology followed ISO 16140-2: 2016, with the analysis naturally contaminated drag swab samples collected from broiler aviaries and artificially contaminated with salmonella ATCCs. Of the 300 samples processed in protocol A (pre-enrichment tetrathionate broth (TT)), 45 were positive for Salmonella sp., 242 negative, one false-positive, and 12 false-negative, while of the 300 samples analyzed in protocol B (pre-enrichment brain-heart infusion broth (BHI)), 40 were positive, 256 negative, one false-positive, and three false-negative. The result for protocol A was a sensitivity of 79%, specificity of 99.6%, Positive Predictive Value (PPV) of 98%, and Negative Predictive Value (NPV) of 95%; and for protocol B, 93% sensitivity, 99.6% specificity, 98% PPV, and 99% NPV. Both protocols were associated with the reference method (p>0.05), concluding that the MDS® can be used for the qualitative detection of Salmonella sp.

The study aimed to characterize the digestive tract of Uranoscodon superciliosus and its associations to the diet and foraging behavior already described for the species. Five lizards were captured in forest areas near the city of Manaus, Amazonas, Brazil. Tongue, oesophagus, stomach, small and large intestines fragments were collected, fixed, and processed for light microscopy. Hyaline cartilage was present in the center of the tongue, and the papillae from the apex and glands from the radix showed positive reaction to Alcian blue. The oesophagus presented a folded mucosa, covered by an epithelium with mucous and goblet cells positive to PAS and Alcian blue. There was presence of gastric glands in the cardic and fundic stomach regions, plus all the regions reacted positively to PAS. Fold and villi variations in both small and large intestine were noted, as well as the number and arrangement of goblet cells. Mucous and goblet cells from the small intestine were positively stained in PAS, while only the goblet cells were Alcian blue positive. These findings indicate that the Amazonian Diving Lizard's digestive tract organs, mainly the tongue and stomach, present morphologies associated to ambush-type foraging and a specific diet largely based on small invertebrates.

The need for the identification of risk factors associated to COVID-19 disease severity remains urgent. Patients' care and resource allocation can be potentially different and are defined based on the current classification of disease severity. This classification is based on the analysis of clinical parameters and routine blood tests, which are not standardized across the globe. Some laboratory test alterations have been associated to COVID-19 severity, although these data are conflicting partly due to the different methodologies used across different studies. This study aimed to construct and validate a disease severity prediction model using machine learning (ML). Seventy-two patients admitted to a Brazilian hospital and diagnosed with COVID-19 through RT-PCR and/or ELISA, and with varying degrees of disease severity, were included in the study. Their electronic medical records and the results from daily blood tests were used to develop a ML model to predict disease severity. Using the above data set, a combination of five laboratorial biomarkers was identified as accurate predictors of COVID-19 severe disease with a ROC-AUC of 0.80 ​±​ 0.13. Those biomarkers included prothrombin activity, ferritin, serum iron, ATTP and monocytes. The application of the devised ML model may help rationalize clinical decision and care.

The presence of humans frequently modifies the behavior of animals, particularly their foraging patterns, compromising energetic demands. The fiddler crab Leptuca leptodactyla inhabits mangroves with high degrees of anthropogenic influence. Thus, we tested if populations living in highly anthropized mangroves respond differently from those living in more protected areas. We predict that individuals from touristy areas will be more tolerant to humans and will resume their activities sooner after disturbance. To do so, we conducted an experiment that consisted in the approach of an observer to the burrows, recording the response of individuals to the stimuli. The experiment took place in July 2022, in Ubatuba, São Paulo, Brazil. We analysed the duration and latency of various behaviors of a total of 80 adult males from two populations (high and low anthropogenic influence). Contrary to our predictions, individuals from the anthropized population were less tolerant, spending more time inside their burrows and taking longer to resume their activities. Therefore, fiddler crabs were not habituated to human presence. These results help us understand the learning process in invertebrates and their ability to select stimuli, contributing to understanding the impacts of human-wildlife interactions.

A new species of Asplenium L. (Aspleniaceae) is described and illustrated. Asplenium sylvaticum is endemic of the Yungas and Paraná biogeographic provinces in the Southern Cone. The main diagnostic characters for this taxon are: apical pinnae with one to four caudate lobes at the base, similar in size to lateral pinnae, smooth pinnate blades with 18-36 pairs of caudate pinnae and spores with reticulate perispore, winged folds with scarce equinulaes on the margins and the laesurae wide with smooth margin. The new species belongs to the A. serra species complex group, characterised by xeromorphic habit, creeping rhizome and coriaceous fronds with branched scales on both surfaces, and resembles the other species inhabiting in Argentina, A. achalense and A. serra, in overall leaf architecture and shape but differs of the aforementioned species (and the other species of the A. serra complex) by the unique combination of characters of its rhizomatic scales, fronds and spores. A key with the morphological and palynological characters that differentiate A. sylvaticum from the other taxa belonging to the A. serra complex in the South American Cone and Bolivia is given.

The tumor microenvironment (TME) harbors several cell types, such as tumor cells, immune cells, and non-immune cells. These cells communicate through several mechanisms, such as cell-cell contact, cytokines, chemokines, and extracellular vesicles (EVs). Tumor-derived vesicles are known to have the ability to modulate the immune response. Monocytes are a subset of circulating innate immune cells and play a crucial role in immune surveillance, being recruited to tissues where they differentiate into macrophages. In the context of tumors, it has been observed that tumor cells can attract monocytes to the TME and induce their differentiation into tumor-associated macrophages with a pro-tumor phenotype. Tumor-derived EVs have emerged as essential structures mediating this process. Through the transfer of specific molecules and signaling factors, tumor-derived EVs can shape the phenotype and function of monocytes, inducing the expression of cytokines and molecules by these cells, thus modulating the TME towards an immunosuppressive environment.