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Oliveira, M. A.

Publications and source records attributed to Oliveira, M. A..

4 recordsLinked to original sources

Prioritizing Neglected Food Species in Nutritional Studies Using Expert-Knowledge and Explainable AI

Food biodiversity is vital for human health and sustainable food systems. However, research on neglected and underutilized species is limited by funding, uneven research capacity, and the challenge of balancing ecological, cultural, and public health considerations, requiring innovative prioritization approaches. Using Brazil as a model, this study inventories 369 neglected food species across algae, aquatic fauna, wild terrestrial vertebrates, insects, mushrooms, and plants. A mixed-methods approach, combining expert knowledge and explainable AI (LightGBM and SHAP value analysis), identified key factors for prioritizing species for food composition and consumption studies. The inventory is dominated by plants (29.5%) and wild vertebrates (24.4%), with major nutritional data gaps, particularly for algae, insects, and wild vertebrates. Over 36,000 recipes using neglected species were identified. In both food composition (R{superscript 2}: 0.677) and consumption studies (R{superscript 2}: 0.782) recipe number and species occurrence across different states were the most influential features predicting prioritization. These findings emphasize the role of cultural uses and local accessibility in shaping nutritional research priorities. We urge increased research on neglected species to bridge data gaps and integrate them into food systems, promoting sustainable diets in Brazil and other tropical regions.

ecology↗

TGF-β and BMP subfamily pathways in zebrafish spermatogonial niche: A83-01 and DMH1 inhibitor effects in spermatogonial self-renewal and differentiation

This study unravels the roles of TGF-{beta} (Transforming growth factor-{beta}) superfamily signaling pathway in the zebrafish spermatogonial activity (self-renewal vs. differentiation) by combining ex vivo and specific pathway inhibitors approaches. The TGF-{beta} superfamily signaling pathway is subdivided into TGF-{beta} and Bone morphogenetic proteins (BMP) subfamilies, and is ubiquitous among metazoans, regulating several biological processes, including spermatogenesis. In this study, we evaluated the function of the TGF-{beta} and BMP subfamily pathways in the zebrafish spermatogonial niche using A83-01 and DMH1 inhibitors, respectively. Our results showed that A83-01 potentiated the follicle-stimulating hormone (Fsh) effects on zebrafish spermatogenesis, reducing type A undifferentiated spermatogonia and increasing differentiated spermatogonia (type Adiff and type B spermatogonia) after 7 days of culture. In agreement with histomorphometrical data, the mRNA levels of dazl (marker of spermatogonial differentiation) and pro-differentiation growth factors, such as igf3 and insl3, were significantly augmented following A83-01. For the BMP signaling pathway, exposure to DMH1 inhibitor showed opposite effects as compared to TGF-{beta} superfamily signaling pathway inhibitor. Histomorphometrical analysis demonstrated an accumulation of type A undifferentiated spermatogonia, while the frequency of differentiated spermatogonia was significantly reduced following co-treatment of DMH1 with Fsh after 7 days of culture. To support this data, expression analysis revealed that BMP signaling pathway inhibitor also decreased the testicular mRNA levels of dazl, igf3 and insl3 when compared to control incubation (Fsh). In conclusion, our study demonstrated that TGF-{beta} and BMP subfamily pathways exert a role in zebrafish spermatogonial niche with antagonistic functions for the spermatogonia fate. The TGF-{beta} subfamily pathway is involved with spermatogonial self-renewal and inhibition of differentiation, whereas the BMP subfamily pathway promotes spermatogonial differentiation. These findings are not only relevant to understanding stem cell biology, but may also be useful in several in vitro assays, promoting control of self-renewal and differentiation by potentially directing these processes.

cell biology↗

The connectome is necessary but not sufficient for the spread of alpha-synuclein pathology in rats

Certain neuronal populations are selectively vulnerable to alpha-synuclein pathology in Parkinsons Disease, yet the reasons for this selectivity are unclear. Pathology affects neuronal populations that are anatomically connected although the contribution of neuronal connectivity remains to be quantitatively explored. Herein, we simulate the contribution of the connectome alone to the spread of arbitrary aggregates using a computational model of temporal spread within an abstract representation of the mouse mesoscale connectome. Our simulations are compared with the neuron-to-neuron spread of alpha-synuclein that has been observed with in vivo spreading experiments in rats. We find that neuronal connectivity appears to be compatible with the spreading pattern of alpha-synuclein pathology however, it may be per se insufficient to determine the anatomical pattern of protein spreading observed in experimental animals, suggesting a role of selective vulnerability of neuronal pathways to alpha-synuclein diffusion, accumulation and pathology.\n\nGraphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

neuroscience↗

A hidden battle in the dirt: soil amoebae interactions with Paracoccidioides spp

Paracoccidioides spp. are thermodimorphic pathogenic fungi endemic to Latin America. Predation is believed to drive the evolution of virulence for soil saprophytes. We evaluated the presence of environmental amoeboid predators in soil from armadillo burrows where Paracoccidioides had been previously detected and tested if interaction of Paracoccidioides with amoebae increased fungal virulence. Nematodes, ciliates and amoebae - all potential predators of fungi - grew in cultures from soil samples. Microscopical observation and ITS sequencing identified the amoebae as Acanthamoeba spp, Allovahlkampfia spelaea and Vermamoeba vermiformis. These three amoebae efficiently ingested, killed and digested Paracoccidioides spp. yeast cells, as did laboratory-adapted axenic Acanthamoeba castellanii. Sequential co-cultivation of Paracoccidioides with A. castellanii selected for phenotypical traits related to survival of the fungus within a natural predator as well as in murine macrophages and in vivo (Galleria mellonella and mice). This increase in virulence is linked to the accumulation of cell wall alpha-glucans, polysaccharides that masks recognition of fungal molecular patterns by host pattern recognition receptors. Altogether, our results indicate that Paracoccidioides inhabits a complex environment with multiple amoeboid predators that can exert selective pressure to guide the evolution of virulence traits.

microbiology↗