46 research outputs found
Intercropping of tomato with antagonistic plants in the treatment of soil infested with Meloidogyne spp., under greenhouse
El intercultivo de tomate con especies antagónicas se considera una alternativa de manejo de Meloidogyne spp. El objetivo del trabajo fue evaluar el intercultivo de las especies Tagetes erecta, Tagetes minuta y Crotalaria juncea para el manejo de Meloidogyne spp., en el cultivo de tomate. Se determinó, en las plantas de tomate, el índice de agallas y el número y peso de frutos. El intercultivo de tomate con T. erecta mostro un menor índice de agallas que el resto de los tratamientos evaluados. Además, se observó en este tratamiento, y en el de T. minuta, un mayor peso y número de frutos con respecto al tratamiento con C. juncea y al testigo sin intercultivo. En las condiciones de este ensayo, el intercultivo de tomate con T. erecta mostró ser una buena alternativa de manejo de Meloidoigyne spp. Se contribuye con esta práctica a una menor utilización de fitosanitarios, con el efecto positivo que trae aparejado para con el medio ambiente, y a la obtención de un producto hortícola de mayor inocuidad para el consumo.Tomato intercropping with antagonistic species is considered a management alternative for Meloidogyne spp. The objective of the work was to evaluate the intercropping of Tagetes erecta, Tagetes minuta and Crotalaria juncea for the management of Meloidogyne spp., in tomato cultivation. The gall index and the number and weight of fruits were determined in tomato plants. Tomato intercropping with T. erecta showed a lower gall index than the rest of evaluated treatments. In addition, a higher weight and number of fruits were observed in this treatment and in the one with T. minuta, respect to the C. juncea treatment and the control without intercropping. Under the conditions of this trial, intercropping of tomato with T. erecta proved to be a good alternative for the management of Meloidoigyne spp. This practice contributes to a lesser use of phytosanitary products, with the positive effect that it has on the environment, and to the obtaining of a more innocuous horticultural product for human consumption.Fil: Comezaña, María Micaela. Universidad Nacional del Sur. Departamento de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; ArgentinaFil: Rodríguez, R. A.. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Ayastuy, M. E.. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Muscolino, C.. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Rosetti, F.. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Belladonna, D. P.. Universidad Nacional del Sur. Departamento de Agronomía; Argentin
Engagement of nuclear coactivator 7 by 3-hydroxyanthranilic acid enhances activation of aryl hydrocarbon receptor in immunoregulatory dendritic cells
Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the first step in the kynurenine pathway of tryptophan (Trp) degradation that produces several biologically active Trp metabolites. L-kynurenine (Kyn), the first byproduct by IDO1, promotes immunoregulatory effects via activation of the Aryl hydrocarbon Receptor (AhR) in dendritic cells (DCs) and T lymphocytes. We here identified the nuclear coactivator 7 (NCOA7) as a molecular target of 3-hydroxyanthranilic acid (3-HAA), a Trp metabolite produced downstream of Kyn along the kynurenine pathway. In cells overexpressing NCOA7 and AhR, the presence of 3-HAA increased the association of the two molecules and enhanced Kyn-driven, AhR-dependent gene transcription. Physiologically, conventional (cDCs) but not plasmacytoid DCs or other immune cells expressed high levels of NCOA7. In cocultures of CD4+ T cells with cDCs, the co-addition of Kyn and 3-HAA significantly increased the induction of Foxp3+ regulatory T cells and the production of immunosuppressive transforming growth factor β in an NCOA7-dependent fashion. Thus, the co-presence of NCOA7 and the Trp metabolite 3-HAA can selectively enhance the activation of ubiquitary AhR in cDCs and consequent immunoregulatory effects. Because NCOA7 is often overexpressed and/or mutated in tumor microenvironments, our current data may provide evidence for a new immune check-point mechanism based on Trp metabolism and AhR
Deficiency of immunoregulatory indoleamine 2,3-dioxygenase 1 in juvenile diabetes
A defect in indoleamine 2,3-dioxygenase 1 (IDO1), which is responsible for immunoregulatory tryptophan catabolism, impairs development of immune tolerance to autoantigens in NOD mice, a model for human autoimmune type 1 diabetes (T1D). Whether IDO1 function is also defective in T1D is still unknown. We investigated IDO1 function in sera and peripheral blood mononuclear cells (PBMCs) from children with T1D and matched controls. These children were further included in a discovery study to identify SNPs in IDO1 that might modify the risk of T1D. T1D in children was characterized by a remarkable defect in IDO1 function. A common haplotype, associated with dysfunctional IDO1, increased the risk of developing T1D in the discovery and also confirmation studies. In T1D patients sharing such a common IDO1 haplotype, incubation of PBMCs in vitro with tocilizumab (TCZ) - an IL-6 receptor blocker - would, however, rescue IDO1 activity. In an experimental setting with diabetic NOD mice, TCZ was found to restore normoglycemia via IDO1-dependent mechanisms. Thus, functional SNPs of IDO1 are associated with defective tryptophan catabolism in human T1D, and maneuvers aimed at restoring IDO1 function would be therapeutically effective in at least a subgroup of T1D pediatric patients.The authors wish to thank patients and subjects who participated in this study, as well as nurses and staff of the Pediatric Clinic of S. Maria della Misericordia Hospital (Perugia), Juvenile Diabetes Center-Anna Meyer Children's Hospital (Florence), Unit of Endocrinology and Diabetes-'Bambino Gesu' Children's Hospital (Rome), Hopital Necker-Enfants Malades (Paris), and Diabetes and Metabolism Service-University Hospital Centre of Coimbra (Coimbra). The authors wish also to thank Roberto Gerli for the gift of TCZ, Giovanni Ricci for histologies, and Francisco Carrilho and Eduarda Coutinho for providing and processing, respectively, DNA samples from the Portuguese cohorts. This work was supported by the European Research Council (338954-DIDO to UG) and, in part, by Associazione per l'Aiuto ai Giovani con Diabete Italia e dell'Umbria (to UG) and the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) (NORTE-01-0145-FEDER-000013 to AC) and the Fundacao para a Ciencia e Tecnologia (contracts IF/00735/2014 to AC, and SFRH/BPD/96176/2013 to CC).info:eu-repo/semantics/publishedVersio
Contrast-enhanced micro-CT to assess dental pulp tissue debridement in root canals of extracted teeth: a series of cascading experiments towards method validation
AIM
To validate a new method for the evaluation of pulp tissue debridement in the root canals of extracted teeth using an impregnation protocol involving potassium triiodide, a radiocontrast solution known as Lugol's, combined with micro-computed tomographic (micro-CT) imaging.
METHODOLOGY
The impact of NaOCl on the radiopacity of Lugol's solution was assessed using a two-fold dilution series of Lugol in distilled water and 5.25% NaOCl, which were then pipetted into transparent dishes and radiographed. To verify the influence of Lugol on the proteolytic effect of NaOCl, a dissolution test was performed using fresh bovine meat. Ten slices did not undergo any tissue processing, whilst twenty slices were fixed in formaldehyde for 24 h. After that, 10 of them were immersed in Lugol for another 24 h. Then, all specimens were placed in NaOCl and the time required for a complete tissue dissolution was recorded. For the last experiments (histological validation and micro-CT assessment), 8 extracted mandibular premolars with formerly vital pulps were immersed in buffered formalin, scanned in a micro-CT device, accessed, immersed in Lugol for 7 days and scanned again. Then, the root canals of 5 teeth were prepared and scanned, and the volume of remaining pulp tissue identified and quantified, whilst 3 teeth were histologically processed. The same specimens were subjected to histological assessment, and the images of the histologic sections were registered with the corresponding micro-CT images to verify whether the pulp tissue in the histological sections matched its counterpart in the Lugol-impregnated tissues identified in the micro-CT slices.
RESULTS
There was no discernible effect on radiopacity when NaOCl was mixed with Lugol's solution. Tissue processing did not affect the time required for the complete dissolution of fresh bovine meat. Histological evaluation revealed a correlation between micro-CT and histological images confirming the identification of Lugol-impregnated pulp tissue in micro-CT images.
CONCLUSIONS
The radiocontrast Lugol's solution was unaffected by NaOCl and did not interfere with its soft tissue dissolution capability. The impregnation protocol using Lugol's solution allowed the visualization of pulp tissue on the micro-CT images and the identification of pulp remnants after chemical-mechanical canal procedures
Do pre-existing microcracks play a role in the fracture resistance of roots in a laboratory setting?
Aim
To investigate a potential cause–effect relationship between dentinal microcracks and fracture resistance of mandibular incisors that had not been endodontically treated.
Methodology
Sixty mandibular incisors with circular‐shaped canals were selected based on micro‐computed tomographic scans to create a homogeneous sample. The cross‐sectional images of the specimens were screened to identify and quantify the presence of dentinal microcracks. Then, teeth were embedded in polystyrene resin and subjected to axial compressive loading using a universal testing machine. After fracture, the roots were re‐scanned and fractography analysis was performed by inspection of 3D models to verify crack propagation. Spearman’s rank correlation was used to assess the correlation between the number of microcracks and force required to fracture.
Results
Dentinal microcracks were detected in 79% of the specimens (n = 44). The incidence of microcracks varied between teeth from 6% to 42% of the total slices per sample (average of 14 ± 17%). The number of microcracks per sample varied from 0 to 1605, with an average of 412 ± 484 (median = 221 and IQR 25% = 15/75% = 658). The load at failure values varied from 227 to 924 N, with an average of 560.3 ± 168.1 N (median = 561 and IQR 25% = 458/75% = 694). The Spearman correlation coefficient (rho) equalled 0.065.
Conclusions
There was no cause–effect relationship between the number of dentinal microcracks and the fracture resistance of nonendodontically treated mandibular incisors. The presence and quantity of microcracks did not make these roots more prone to fracture
High doses of CpG oligodeoxynucleotides stimulate a tolerogenic TLR9–TRIF pathway
CpG-rich oligodeoxynucleotides activate the immune system, leading to innate and acquired immune responses. The immune-stimulatory effects of CpG-rich oligodeoxynucleotides are being exploited as a therapeutic approach. Here we show that at high doses, CpG-rich oligodeoxynucleotides promote an opposite, tolerogenic response in mouse plasmacytoid dendritic cells in vivo and in a human in vitro model. Unveiling a previously undescribed role for TRIF and TRAF6 proteins in Toll-like receptor 9 (TLR9) signalling, we demonstrate that physical association of TLR9, TRIF and TRAF6 leads to activation of noncanonical NF-κB signalling and the induction of IRF3- and TGF-β-dependent immune-suppressive tryptophan catabolism. In vivo, the TLR9-TRIF circuit--but not MyD88 signalling--was required for CpG protection against allergic inflammation. Our findings may be relevant to an increased understanding of the complexity of Toll-like receptor signalling and optimal exploitation of CpG-rich oligodeoxynucleotides as immune modulators
Contrast‐enhanced micro‐CT to assess dental pulp tissue debridement in root canals of extracted teeth: a series of cascading experiments towards method validation
Aim
To validate a new method for the evaluation of pulp tissue debridement in the root canals of extracted teeth using an impregnation protocol involving potassium triiodide, a radiocontrast solution known as Lugol’s, combined with micro‐computed tomographic (micro‐CT) imaging.
Methodology
The impact of NaOCl on the radiopacity of Lugol’s solution was assessed using a two‐fold dilution series of Lugol in distilled water and 5.25% NaOCl, which were then pipetted into transparent dishes and radiographed. To verify the influence of Lugol on the proteolytic effect of NaOCl, a dissolution test was performed using fresh bovine meat. Ten slices did not undergo any tissue processing, whilst twenty slices were fixed in formaldehyde for 24 h. After that, 10 of them were immersed in Lugol for another 24 h. Then, all specimens were placed in NaOCl and the time required for a complete tissue dissolution was recorded. For the last experiments (histological validation and micro‐CT assessment), 8 extracted mandibular premolars with formerly vital pulps were immersed in buffered formalin, scanned in a micro‐CT device, accessed, immersed in Lugol for 7 days and scanned again. Then, the root canals of 5 teeth were prepared and scanned, and the volume of remaining pulp tissue identified and quantified, whilst 3 teeth were histologically processed. The same specimens were subjected to histological assessment, and the images of the histologic sections were registered with the corresponding micro‐CT images to verify whether the pulp tissue in the histological sections matched its counterpart in the Lugol‐impregnated tissues identified in the micro‐CT slices.
Results
There was no discernible effect on radiopacity when NaOCl was mixed with Lugol’s solution. Tissue processing did not affect the time required for the complete dissolution of fresh bovine meat. Histological evaluation revealed a correlation between micro‐CT and histological images confirming the identification of Lugol‐impregnated pulp tissue in micro‐CT images.
Conclusions
The radiocontrast Lugol’s solution was unaffected by NaOCl and did not interfere with its soft tissue dissolution capability. The impregnation protocol using Lugol’s solution allowed the visualization of pulp tissue on the micro‐CT images and the identification of pulp remnants after chemical–mechanical canal procedures
Ten-Year Retrospective Analysis of Legionella Diffusion in Hospital Water Systems and Its Serogroup Seasonal Variation
Do pre‐existing microcracks play a role in the fracture resistance of roots in a laboratory setting?
Aim
To investigate a potential cause–effect relationship between dentinal microcracks and fracture resistance of mandibular incisors that had not been endodontically treated.
Methodology
Sixty mandibular incisors with circular‐shaped canals were selected based on micro‐computed tomographic scans to create a homogeneous sample. The cross‐sectional images of the specimens were screened to identify and quantify the presence of dentinal microcracks. Then, teeth were embedded in polystyrene resin and subjected to axial compressive loading using a universal testing machine. After fracture, the roots were re‐scanned and fractography analysis was performed by inspection of 3D models to verify crack propagation. Spearman’s rank correlation was used to assess the correlation between the number of microcracks and force required to fracture.
Results
Dentinal microcracks were detected in 79% of the specimens (n = 44). The incidence of microcracks varied between teeth from 6% to 42% of the total slices per sample (average of 14 ± 17%). The number of microcracks per sample varied from 0 to 1605, with an average of 412 ± 484 (median = 221 and IQR 25% = 15/75% = 658). The load at failure values varied from 227 to 924 N, with an average of 560.3 ± 168.1 N (median = 561 and IQR 25% = 458/75% = 694). The Spearman correlation coefficient (rho) equalled 0.065.
Conclusions
There was no cause–effect relationship between the number of dentinal microcracks and the fracture resistance of nonendodontically treated mandibular incisors. The presence and quantity of microcracks did not make these roots more prone to fracture