During
Trypanosoma cruzi
infection, macrophages phagocytose parasites and remove apoptotic cells through efferocytosis. While macrophage 1 (M1) produces proinflammatory cytokines and NO and fights ...infection, M2 macrophages are permissive host cells that express arginase 1 and play a role in tissue repair. The regulation of M1 and M2 phenotypes might either induce or impair macrophage-mediated immunity towards parasite control or persistence in chronic Chagas disease. Here, we highlight a key role of macrophage activation in early immune responses to
T. cruzi
that prevent escalating parasitemia, heart parasitism, and mortality during acute infection. We will discuss the mechanisms of macrophage activation and deactivation, such as T cell cytokines and efferocytosis, and how to improve macrophage-mediated immunity to prevent parasite persistence, inflammation, and the development of chagasic cardiomyopathy. Potential vaccines or therapy must enhance early T cell-macrophage crosstalk and parasite control to restrain the pathogenic outcomes of parasite-induced inflammation in the heart.
Within the subfamily Edessinae, Edessa Fabricius, 1803 is the genus with the most nomenclatural and taxonomic issues, basically related to the large number of poorly described species and the large ...number of new species. Furthermore, for many groups of morphologically similar species, certain names are used as tag names, adding to confusion and misidentification. The genus Edessa has been studied in small groups of species, either informal morphological groups within the genus or formal subgenera. Recently the nominal subgenus was revised and delimited, including the group E. sexdens. The E. sexdens group is diagnosed by a combination of characters such as anterior arms of metasternal process with excavated apex; connexival segments with a pair of dark spots; ventral surface of abdomen elevated medially; presence of a shallow rounded excavation near each spiracle; pygophore with union of dorsal rim and posterolateral angles with a groove, superior processes of the genital cup laminar, oblique to the paramere and continued ventrally by a carina; and paramere with three lobes. The biology of species in this group is almost unknown and most species have been collected in the Amazon region, particularly in the Brazilian Amazon. This group is the largest, in number of species, within the subgenus Edessa, presenting a surprising number of new species. In this article, fifty-one species new to science are described and Olbia magnifica Pirn, 1958 is transferred to Edessa. The composition of the E. sexdens group is updated to 74 species (23 previously described and 51 described here). The identification key to the species of the E. sexdens group is updated, and maps with the distribution of the new species are presented.
PI3K/Akt is an important pathway implicated in the proliferation and survival of cells in the CNS. Here we investigated the participation of the PI3K/Akt signal pathway in cell cycle of developing ...retinal progenitors. Immunofluorescence assays performed in cultures of chick embryo retinal cells and intact tissues revealed the presence of phosphorylated Akt and 4E-BP1 in cells with typical mitotic profiles. Blockade of PI3K activity with the chemical inhibitor LY 294002 (LY) in retinal explants blocked the progression of proliferating cells through G2/M transition, indicated by an expressive increase in the number of cells labeled for phosphorylated histone H3 in the ventricular margin of the retina. No significant level of cell death could be detected at this region. Retinal explants treated with LY for 24 h also showed a significant decrease in the expression of phospho-Akt, phospho-GSK-3 and the hyperphosphorylated form of 4E-BP1. Although no change in the expression of cyclin B1 was detected, a significant decrease in CDK1 expression was noticed after 24 h of LY treatment both in retinal explants and monolayer cultures. Our results suggest that PI3K/Akt is an active pathway during proliferation of retinal progenitors and its activity appears to be required for proper CDK1 expression levels and mitosis progression of these cells.
Hormonal, biochemical, and metabolic changes after menopause may alter the quality of life of women, leading to vasomotor, psychological, and genitourinary symptoms, and changes in their gut ...microbiota, which regulates estrogen levels through the estroboloma. Fecal samples were used to investigate the changes in the gut microbiota during aging and hormonal changes in women. A balanced gut microbiota has been associated with health or disease conditions and remains poorly understood after menopause. This study identified the fecal microbiota, and their association with biochemical and hormonal parameters of a cohort of women in the climacteric in the city of Ouro Preto-MG, Brazil.
A total of 102 women aged 40 to 65 years old were recruited and distributed into three groups according to the STRAW criteria for reproductive stage: reproductive (n = 18), premenopausal (n = 26), and postmenopausal (n = 58). Blood samples were collected to measure their serum biochemical and hormone levels, and the participants answered a questionnaire. The gut microbiota was analyzed from fecal samples by qPCR using the genera Bifidobacterium, Bacteroides, Lactobacillus, and Clostridium.
The following parameters showed differences among the groups: total cholesterol, triglycerides, VLDL, ApoB, urea, calcium, uric acid, and alkaline phosphatase (p < 0.05). qPCR revealed the genus Clostridium to be the most abundant in all three groups. In the reproductive age group, the significant correlations were: Bacteroides with glucose (r = -0.573 p = 0.0129), and SDHEA (r = -0.583 p = 0.0111). For the premenopausal group, they were: Bifidobacteria with total cholesterol (r = 0.396 p = 0.0451), LDL (r = 0.393 p = 0.0468), ApoB (r = 0.411 p = 0.0368); Lactobacillus and calcium (r = 0.443 p = 0.0232), ALP (r = 0.543 p = 0.0041), LPa (r =-0.442 p = 0.02336); and Bacteroides and urea (r =-0.461 p = 0.0176). In the postmenopausal group, they were Bifidobacterium and ALP (r =-0.315 p = 0.0159), Lactobacillus and urea (r =-0.276 p = 0.0356), and Clostridium and beta estradiol (r =-0.355 p = 0.0062).
In conclusion, the hormonal and metabolic changes during menopause in the population studied were accompanied by a significant change in the fecal microbiota, especially of the genus Clostridium.
Arterialization of the dorsal venous arch of the foot is a technique indicated in cases of critical lower limb ischemia that do not have a distal bed that is adequate to enable conventional treatment ...such as revascularization, angioplasty, or clinical treatment.
The purpose of this study is to present the result of arterialization of the venous arch of the foot in 16 patients who underwent treatment with this technique.
This is a cross-sectional retrospective descriptive analytical study based on a review of the medical records of 16 patients who underwent arterialization of the dorsal venous arch of the foot for limb salvage from January 2016 to January 2021.
Four (25%) of the 16 patients who underwent arterialization of the venous arch of the foot underwent a major amputation during the same hospital stay and one patient (6.25%) had a major amputation within 6 months. The other 11 patients (68.75%) had their limbs preserved, with 10 undergoing minor amputations (toes and forefoot) and one patient having no additional procedures.
We conclude that the technique of arterialization of the dorsal venous arch of the foot should be considered in selected cases. It is a valid alternative for limb salvage when conventional treatment is impossible.
Adaptive immunity controls Trypanosoma cruzi infection, but the protozoan parasite persists and causes Chagas disease. T cells undergo apoptosis, and the efferocytosis of apoptotic cells might ...suppress macrophages and exacerbate parasite infection. Nonetheless, the receptors involved in the efferocytosis of apoptotic lymphocytes during infection remain unknow. Macrophages phagocytose apoptotic cells by using the TAM (Tyro3, Axl, Mer) family of receptors. To address how the efferocytosis of apoptotic cells affects macrophage-mediated immunity, we employ here Axl receptor- and Mer receptor-deficient mouse strains. In bone marrow-derived macrophages (BMDMs), both Axl and Mer receptors play a role in the efferocytosis of proapoptotic T cells from T. cruzi-infected mice. Moreover, treatment with a TAM receptor inhibitor blocks efferocytosis and upregulates M1 hallmarks induced by immune T cells from infected mice. Remarkably, the use of Axl
but not Mer
macrophages increases T-cell-induced M1 responses, such as nitric oxide production and control of parasite infection. Furthermore, infected Axl
mice show reduced peak parasitemia, defective efferocytosis, improved M1 responses, and ameliorated cardiac inflammation and fibrosis. Therefore, Axl induces efferocytosis, disrupts M1 responses, and promotes parasite infection and pathology in experimental Chagas disease. Axl stands as a potential host-direct target for switching macrophage phenotypes in infectious diseases.
The new group of species viridula is proposed to five new species: Edessa viridula sp. n., Edessa exigusternata sp. n., Edessa angusticlada sp. n., Edessa rugulata sp. n. and Edessa eucnema sp. n. ...based on 58 specimens examined. Descriptions of the group and species are provided. Illustrations of the species along with metasternal process and male and female genitalia are provided; an identification key and distributional map are presented.
Creating robust datasets of plant–insect interactions is important for understanding ecosystem dynamics, and data on species interactions can be used to evaluate conservation interventions. In the ...present work, we collected plant–herbivore–parasitoid data on an understudied but critical ecosystem—gallery forests in the Brazilian cerrado. We collected caterpillars on shrubs of
Piper
(Piperaceae) over the course of a year in seven gallery forests of varying sizes in order to compare seasonal changes in
α
- and
β
- diversity and tritrophic interaction networks as well as the role of fragment size in determining species and interaction diversity. Caterpillars were more abundant and diverse in the wet season and also increased with resource availability—the more
Piper
individuals present, the greater the abundance and richness of herbivores. The number of unique interactions between (i) plants and herbivores and (ii) herbivores and parasitoids did not change across seasons, but there was a high degree of turnover in the herbivore fauna between sites and seasons. Specialization was greatest in the dry-rainy season transition, when new leaves typically flush. Consistent with records of parasitism rates in the cerrado sensu stricto
,
parasitism in the gallery forests was greatest in the dry-rainy seasons. Forest size was not related to caterpillar richness. Overall, this work demonstrates the conservation value of gallery forests in supporting plant species that span the Amazon and the Atlantic Rainforest as well as diverse and highly seasonal trophic interactions.
Introduction: In animals, body size is correlated with many aspects of natural history, such as life span, abundance, dispersal capacity and diet breadth. However, contrasting trends have been ...reported for the relationship between body size and these ecological traits. Methods: Fruit-feeding butterflies were used to investigate whether body size is correlated with species abundance, dispersal, permanence, and larval diet breadth in a Neotropical savanna in Brazil (Cerrado). We used Blomberg’s K and Phylogenetic Generalized Least Squares models (PGLS) to measure phylogenetic signal strength in species traits and to estimate size–dispersal–diet breadth associations, while also taking shared ancestry into account. Results: 539 individuals from 27 species were captured, and 190 individuals were recaptured, representing a 35% recapture rate. We found body size to be negatively associated with butterfly abundance, and positively associated with dispersal level, distance traveled, number of traps visited, individual permanence, and diet breadth. These results indicate that larger butterflies are more likely to disperse over longer distances. Moreover, larger butterflies have more generalized larval diets, based on the number of host plant families, genera, and phylogenetic diversity of the host plants they consume as larvae. Smaller butterflies rely on fewer resources, which is reflected in their higher survival in small patches and may explain their lower dispersal ability and higher diet specialization. Nevertheless, lower dispersal ability may, if not compensated by large population sizes, threaten small-bodied species inhabiting environments, such as the Cerrado, which have intense deforestation rates. Conclusions: Body size is positively associated with dispersal and diet breadth for the fruit-feeding butterflies collected in this study.
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