Cell-Free Antigens from Paracoccidioides brasiliensis Drive IL-4 Production and Increase the Severity of Paracoccidioidomycosis

The thermally dimorphic fungus Paracoccidioides brasiliensis (Pb) is the causative agent of paracoccidioidomycosis (PCM), one of the most frequent systemic mycosis that affects the rural population in Latin America. PCM is characterized by a chronic inflammatory granulomatous reaction, which is consequence of a Th1-mediated adaptive immune response. In the present study we investigated the mechanisms involved in the immunoregulation triggered after a prior contact with cell-free antigens (CFA) during a murine model of PCM. The results showed that the inoculation of CFA prior to the infection resulted in disorganized granulomatous lesions and increased fungal replication in the lungs, liver and spleen, that paralleled with the higher levels of IL-4 when compared with the control group. The role of IL-4 in facilitating the fungal growth was demonstrated in IL-4-deficient- and neutralizing anti-IL-4 mAb-treated mice. The injection of CFA did not affect the fungal growth in these mice, which, in fact, exhibited a significant diminished amount of fungus in the tissues and smaller granulomas. Considering that in vivo anti-IL-4-application started one week after the CFA-inoculum, it implicates that IL-4-CFA-induced is responsible by the mediation of the observed unresponsiveness. Further, the characterization of CFA indicated that a proteic fraction is required for triggering the immunosuppressive mechanisms, while glycosylation or glycosphingolipids moieties are not. Taken together, our data suggest that the prior contact with soluble Pb antigens leads to severe PCM in an IL-4 dependent manner

Amyloid-β Triggers the Release of Neuronal Hexokinase 1 from Mitochondria

Brain accumulation of the amyloid-β peptide (Aβ) and oxidative stress underlie neuronal dysfunction and memory loss in Alzheimer's disease (AD). Hexokinase (HK), a key glycolytic enzyme, plays important pro-survival roles, reducing mitochondrial reactive oxygen species (ROS) generation and preventing apoptosis in neurons and other cell types. Brain isozyme HKI is mainly associated with mitochondria and HK release from mitochondria causes a significant decrease in enzyme activity and triggers oxidative damage. We here investigated the relationship between Aβ-induced oxidative stress and HK activity. We found that Aβ triggered HKI detachment from mitochondria decreasing HKI activity in cortical neurons. Aβ oligomers further impair energy metabolism by decreasing neuronal ATP levels. Aβ-induced HKI cellular redistribution was accompanied by excessive ROS generation and neuronal death. 2-deoxyglucose blocked Aβ-induced oxidative stress and neuronal death. Results suggest that Aβ-induced cellular redistribution and inactivation of neuronal HKI play important roles in oxidative stress and neurodegeneration in AD

Collagenase mRNA Overexpression and Decreased Extracellular Matrix Components Are Early Events in the Pathogenesis of Emphysema.

To describe the progression of parenchymal remodeling and metalloproteinases gene expression in earlier stages of emphysema, mice received porcine pancreatic elastase (PPE) instillation and Control groups received saline solution. After PPE instillation (1, 3, 6 hours, 3 and 21 days) we measured the mean linear intercept, the volume proportion of types I and III collagen, elastin, fibrillin and the MMP-1, -8, -12 and -13 gene expression. We observed an initial decrease in type I (at the 3rd day) and type III collagen (from the 6th hour until the 3rd day), in posterior time points in which we detected increased gene expression for MMP-8 and -13 in PPE groups. After 21 days, the type III collagen fibers increased and the type I collagen values returned to similar values compared to control groups. The MMP-12 gene expression was increased in earlier times (3 and 6 hours) to which we detected a reduced proportion of elastin (3 days) in PPE groups, reinforcing the already established importance of MMP-12 in the breakdown of ECM. Such findings will be useful to better elucidate the alterations in ECM components and the importance of not only metalloelastase but also collagenases in earlier emphysema stages, providing new clues to novel therapeutic targets

The PMN density values are shown in all protocol groups (values as the means and SD).

<p>There was an increase in PMN density in parenchyma in PPE groups compared to respective Control groups in 1h (* p< 0.001), 3 h (* p<0.001), 6 h (* p = 0.008) and 3 d (*p = 0.015).</p

Volume proportion of elastin (A) and fibrillin (B) are shown in all protocol groups (values as the means and SD).

<p>A) Elastin: *p = 0.014 compared to respective S group and ^#p = 0.012 compared to respective S group. B) Fibrillin: There was no significant difference in any of PPE groups compared to their respective S groups.</p

Antibodies used in immunohistochemistry studies.

<p>Antibodies used in immunohistochemistry studies.</p

Antibodies used in immunofluorescence studies.

<p>Antibodies used in immunofluorescence studies.</p

Mean linear intercept (Lm) values measured in all S and PPE groups (A) and photomicrographs of mice lung parenchyma (B and C).

<p>A) *p = 0,021; ^#p<0.001; **p = 0.003; ^§p<0.001; all compared to respective Control group (S). Values are means and SD. B) Photomicrographs of lung parenchyma in S groups at all protocol times. C) Photomicrographs of lung parenchyma in PPE groups at all protocol times. There was an increase in Lm in the PPE groups compared to their respective S controls. (400X magnification, hematoxylin-eosin staining). D) Mean linear intercept (Lm) values measured in Control group (S) and inactive PPE groups. Values are means and SD.</p

Photomicrographs of Elastin, Type I Collagen and Type III Collagen.

<p>A-D) Photomicrographs of elastin in parenchyma (H&E staining, 400X magnification). There was a decrease in elastin amount at the 3^rd day with a posterior increase in such fibers at 21^st day, comparing the PPE with S group. E-F) Photomicrographs of type I collagen staining by immunofluorescense in alveolar tissue (400X magnification). There was a decline in those fibers at the 3^rd day in PPE group; G-L) Photomicrographs of type III collagen staining by immunofluorescense in alveolar tissue (400X magnification). There was a decline in type III collagen at the 6^th hour and 3^rd day with a consecutive increase at the 21^st day in PPE compared with S groups.</p

Uso de manipueira no desenvolvimento vegetativo do milho em ambiente protegido Use of cassava industry wastewater in the vegetative development of corn in a protected environment

Avaliaram-se efeitos da água residuária de fecularia tratada por sistema de lagoas, na cultura do milho. A irrigação com água residuária propiciou aumento de todos os parâmetros químicos do solo, proporcional aos respectivos tratamentos como segue: L1E (efluente da lagoa de decantação), L1ED (efluente da lagoa de decantação diluído em 50%), L2E (efluente da primeira lagoa anaeróbia), L2ED (efluente da primeira lagoa anaeróbia diluído em 50%), L3E (efluente da segunda lagoa anaeróbia), L3ED (efluente da segunda lagoa anaeróbia diluído em 50%) e T (testemunha sem adubação, irrigação com água) exceto para o tratamento TA (testemunha com adubação 85 kg ha-1 K2O; 60 kg ha-1 N; 100 kg ha-1 P2O5 e irrigação com água) que também mostrou altos teores dos elementos avaliados; maiores alturas de planta foram obtidas nos tratamentos L1E, TA, T, os quais diferiram entre si, seguidos de L1ED, L2ED e L3ED, semelhantes estatisticamente, e de L2E e L3E também foram iguais entre si, a 5% de probabilidade; o número de folhas não diferiu significativamente entre tratamentos mas apenas teores de fósforo e zinco mostraram diferenças significativas entre tratamentos nas análises químicas do tecido foliar e das raízes.<br>This study evaluated the effects of the wastewater of cassava industry, treated by pond system, on the corn crop. The irrigation with wastewater resulted in an increase in chemical parameters of the soil, proportional to the respective treatments in the following order: L1E (effluent of the decantation pond), L1ED (effluent of the pond of decantation with 50% dilution), L2E (effluent of the first anaerobic pond), L2ED (effluent of the first anaerobic pond with 50% dilution), L3E (effluent of the second anaerobic pond), L3ED (effluent of the second anaerobic pond with 50% dilution) and T (control without fertilization and irrigation with water) except for the treatment TA (control with fertilization: 85 kg ha-1 K2O; 60 kg ha-1 N; 100 kg ha-1 P2O5 and irrigation with water:); the height of plant for the treatments varied in the following order: L1E, TA, T which differed significantly followed by L1ED, L2ED and L3ED statistically similar; and L2E and L3E which also showed similar results without significant differences at 5% probability level. The number of leaves did not present significant differences among the evaluated treatments, only the concentrations of phosphorus and zinc in the leaves and roots presented significant differences