126 results on '"Dias AA"'
Search Results
2. Adenosine A 2A receptor as a potential regulator of Mycobacterium leprae survival mechanisms: new insights into leprosy neural damage.
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Dos Santos PMF, Díaz Acosta CC, Rosa TLSA, Ishiba MH, Dias AA, Pereira AMR, Gutierres LD, Pereira MP, da Silva Rocha M, Rosa PS, Bertoluci DFF, Meyer-Fernandes JR, da Mota Ramalho Costa F, Marques MAM, Belisle JT, Pinheiro RO, Rodrigues LS, Pessolani MCV, and Berrêdo-Pinho M
- Abstract
Background: Leprosy is a chronic infectious disease caused by Mycobacterium leprae , which can lead to a disabling neurodegenerative condition. M. leprae preferentially infects skin macrophages and Schwann cells-glial cells of the peripheral nervous system. The infection modifies the host cell lipid metabolism, subverting it in favor of the formation of cholesterol-rich lipid droplets (LD) that are essential for bacterial survival. Although researchers have made progress in understanding leprosy pathogenesis, many aspects of the molecular and cellular mechanisms of host-pathogen interaction still require clarification. The purinergic system utilizes extracellular ATP and adenosine as critical signaling molecules and plays several roles in pathophysiological processes. Furthermore, nucleoside surface receptors such as the adenosine receptor A
2A R involved in neuroimmune response, lipid metabolism, and neuron-glia interaction are targets for the treatment of different diseases. Despite the importance of this system, nothing has been described about its role in leprosy, particularly adenosinergic signaling (AdoS) during M. leprae -Schwann cell interaction., Methods: M. leprae was purified from the hind footpad of athymic nu/nu mice. ST88-14 human cells were infected with M. leprae in the presence or absence of specific agonists or antagonists of AdoS. Enzymatic activity assays, fluorescence microscopy, Western blotting, and RT-qPCR analysis were performed. M. leprae viability was investigated by RT-qPCR, and cytokines were evaluated by enzyme-linked immunosorbent assay., Results: We demonstrated that M. leprae -infected Schwann cells upregulated CD73 and ADA and downregulated A2A R expression and the phosphorylation of the transcription factor CREB (p-CREB). On the other hand, activation of A2A R with its selective agonist, CGS21680, resulted in: 1) reduced lipid droplets accumulation and pro-lipogenic gene expression; 2) reduced production of IL-6 and IL-8; 3) reduced intracellular M. leprae viability; 4) increased levels of p-CREB., Conclusion: These findings suggest the involvement of the AdoS in leprosy neuropathogenesis and support the idea that M. leprae , by downmodulating the expression and activity of A2A R in Schwann cells, decreases A2A R downstream signaling, contributing to the maintenance of LD accumulation and intracellular viability of the bacillus., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 dos Santos, Díaz Acosta, Rosa, Ishiba, Dias, Pereira, Gutierres, Pereira, da Silva Rocha, Rosa, Bertoluci, Meyer-Fernandes, da Mota Ramalho Costa, Marques, Belisle, Pinheiro, Rodrigues, Pessolani and Berrêdo-Pinho.)- Published
- 2024
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3. Protein disulfide isomerase-mediated transcriptional upregulation of Nox1 contributes to vascular dysfunction in hypertension.
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Camargo LL, Trevelin SC, da Silva GHG, Dos Santos Dias AA, Oliveira MA, Mikhaylichenko O, Androwiki ACD, Dos Santos CX, Holbrook LM, Ceravolo GS, Denadai-Souza A, Ribeiro IMR, Sartoretto S, Laurindo FRM, Coltri PP, Antunes VR, Touyz R, Miller FJ Jr, Shah AM, and Lopes LR
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- Animals, Rats, Male, Myocytes, Smooth Muscle metabolism, ErbB Receptors metabolism, ErbB Receptors genetics, Rats, Wistar, Transcription, Genetic, Protein Disulfide-Isomerases metabolism, Protein Disulfide-Isomerases genetics, NADPH Oxidase 1 metabolism, NADPH Oxidase 1 genetics, Hypertension physiopathology, Hypertension genetics, Hypertension metabolism, Rats, Inbred SHR, Up-Regulation, Muscle, Smooth, Vascular metabolism
- Abstract
Nox1 signaling is a causal key element in arterial hypertension. Recently, we identified protein disulfide isomerase A1 (PDI) as a novel regulatory protein that regulates Nox1 signaling in VSMCs. Spontaneously hypertensive rats (SHR) have increased levels of PDI in mesenteric resistance arteries compared with Wistar controls; however, its consequences remain unclear. Herein, we investigated the role of PDI in mediating Nox1 transcriptional upregulation and its effects on vascular dysfunction in hypertension. We demonstrate that PDI contributes to the development of hypertension via enhanced transcriptional upregulation of Nox1 in vascular smooth muscle cells (VSMCs). We show for the first time that PDI sulfenylation by hydrogen peroxide contributes to EGFR activation in hypertension via increased shedding of epidermal growth factor-like ligands. PDI also increases intracellular calcium levels, and contractile responses induced by ANG II. PDI silencing or pharmacological inhibition in VSMCs significantly decreases EGFR activation and Nox1 transcription. Overexpression of PDI in VSMCs enhances ANG II-induced EGFR activation and ATF1 translocation to the nucleus. Mechanistically, PDI increases ATF1-induced Nox1 transcription and enhances the contractile responses to ANG II. Herein we show that ATF1 binding to Nox1 transcription putative regulatory regions is augmented by PDI. Altogether, we provide evidence that HB-EGF in SHR resistance vessels promotes the nuclear translocation of ATF1, under the control of PDI, and thereby induces Nox1 gene expression and increases vascular reactivity. Thus, PDI acts as a thiol redox-dependent enhancer of vascular dysfunction in hypertension and could represent a novel therapeutic target for the treatment of this disease., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2024
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4. Whole blood transcriptomics reveals the enrichment of neutrophil activation pathways during erythema nodosum leprosum reaction.
- Author
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Rosa TLSA, Leal-Calvo T, Tavares IF, Mendes MA, Dias AA, Piauy MHDS, Barboza MFDS, Kapuscinski M, Costa FDMR, Marques MAM, Belone AFF, Sales AM, Hacker MA, Moreira MBP, Belisle JT, Moraes MO, Pessolani MCV, and Schmitz V
- Subjects
- Humans, Adult, Male, Female, Middle Aged, GPI-Linked Proteins genetics, Thalidomide, Receptors, Cell Surface genetics, Leprostatic Agents therapeutic use, Leprostatic Agents pharmacology, Young Adult, Biomarkers, Isoantigens, Erythema Nodosum immunology, Erythema Nodosum blood, Neutrophil Activation, Leprosy, Lepromatous immunology, Leprosy, Lepromatous diagnosis, Leprosy, Lepromatous blood, Neutrophils immunology, Neutrophils metabolism, Transcriptome, Gene Expression Profiling
- Abstract
Introduction: Patients with the multibacillary form of leprosy can develop reactional episodes of acute inflammation, known as erythema nodosum leprosum (ENL), which are characterized by the appearance of painful cutaneous nodules and systemic symptoms. Neutrophils have been recognized to play a role in the pathogenesis of ENL, and recent global transcriptomic analysis revealed neutrophil-related processes as a signature of ENL skin lesions., Methods: In this study, we expanded this analysis to the blood compartment, comparing whole blood transcriptomics of patients with non-reactional lepromatous leprosy at diagnosis (LL, n=7) and patients with ENL before administration of anti-reactional treatment (ENL, n=15). Furthermore, a follow-up study was performed with patients experiencing an ENL episode at the time of diagnosis and after 7 days of thalidomide treatment (THAL, n=10). Validation in an independent cohort (ENL=8; LL=7) was performed by RT-qPCR., Results: An enrichment of neutrophil activation and degranulation-related genes was observed in the ENL group, with the gene for the neutrophil activation marker CD177 being the most enriched gene of ENL episode when compared to its expression in the LL group. A more pro-inflammatory transcriptome was also observed, with increased expression of genes related to innate immunity. Validation in an independent cohort indicated that S100A8 expression could discriminate ENL from LL. Supernatants of blood cells stimulated in vitro with Mycobacterium leprae sonicate showed higher levels of CD177 compared to the level of untreated cells, indicating that the leprosy bacillus can activate neutrophils expressing CD177. Of note, suggestive higher CD177 protein levels were found in the sera of patients with severe/moderate ENL episodes when compared with patients with mild episodes and LL patients, highlighting CD177 as a potential systemic marker of ENL severity that deserves future confirmation. Furthermore, a follow-up study was performed with patients at the time of ENL diagnosis and after 7 days of thalidomide treatment (THAL, n=10). Enrichment of neutrophil pathways was sustained in the transcriptomic profile of patients undergoing treatment; however, important immune targets that might be relevant to the effect of thalidomide at a systemic level, particularly NLRP6 and IL5RA , were revealed., Discussion: In conclusion, our study reinforces the key role played by neutrophils in ENL pathogenesis and shed lights on potential diagnostic candidates and novel therapeutic targets that could benefit patients with leprosy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Rosa, Leal-Calvo, Tavares, Mendes, Dias, Piauy, Barboza, Kapuscinski, Costa, Marques, Belone, Sales, Hacker, Berredo-Pinho, Belisle, Moraes, Pessolani and Schmitz.)
- Published
- 2024
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5. WHAT IS THE KNOWLEDGE OF ELEMENTARY SCHOOL TEACHERS ABOUT SCOLIOSIS?
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Dias AA, Cunha MVLD, Gaia LFP, Oliveira NS, Gasparini ALP, Walsh IAP, and Bertoncello D
- Abstract
Objective: To evaluate the knowledge about scoliosis in teachers of municipal public schools., Methods: In total, 126 professionals were interviewed using a standard questionnaire containing issues related to scoliosis., Results: 31% of interviewees did not know what scoliosis is. Of those who knew 89.65% were partially correct about the definition. Of those who claimed to know how the scoliosis diagnosis is made, only 25.58% were completely correct. When questioned about the Adams test, 84.9% did not know it. Among the interviewees, 57.9% answered that it is impossible to identify scoliosis by a simple examination of their students and, off these, 86.3% stated the lack of knowledge about the subject; and 92.1% considered that training for the diagnosis and early identification of scoliosis in students., Conclusion: This study holds social impact since the interviewed teachers were not knowledgeable about the subject and had difficulty in providing a definition of the condition and in how to proceed with the investigation. Continuous education activities and the inclusion of this subject on the curricula of teacher education programs would improve the early diagnosis and treatment of scoliosis, with high success rates. Level of Evidence IV, Economic and Decision Analyses. , Competing Interests: All authors declare no potential conflict of interest related to this article.
- Published
- 2023
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6. Surface modifications to promote the osteoconductivity of ultra-high-molecular-weight-polyethylene fabrics for a novel biomimetic artificial disc prosthesis: An in vitro study.
- Author
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Jacobs CAM, Cramer EEA, Dias AA, Smelt H, Hofmann S, and Ito K
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- Humans, Polyethylenes chemistry, Apatites, Prostheses and Implants, Polyethylene, Alkaline Phosphatase
- Abstract
A novel biomimetic artificial intervertebral disc (bioAID) for the cervical spine was developed, containing a hydrogel core representing the nucleus pulposus, an UHMWPE fiber jacket as annulus fibrosis, and titanium endplates with pins for mechanical fixation. Osseointegration of the UHMWPE fibers to adjacent bone structures is required to achieve proper biomimetic behavior and to provide long-term stability. Therefore, the aim of this study was to assess the osteoconductivity of several surface modifications of UHMWPE fabrics, 2D weft-knitted, using non-treated UHMWPE fibers (N), plasma treated UHMWPE fibers (PT), 10% hydroxy apatite (HA) loaded UHMWPE fibers (10%HA), plasma treated 10%HA UHMWPE fibers (PT-10%HA), 15%HA loaded UHMWPE fibers (15%HA) and plasma treated 15%HA UHMWPE fibers (PT-15%HA). Scanning electron microscopy (SEM) was used for surface characterization. Biological effects were assessed by evaluating initial cell attachment (SEM, DNA content), metabolic activity (PrestoBlue assay), proliferation, differentiation (alkaline phosphatase activity) and mineralization (energy dispersive x-ray, EDX analysis) using human bone marrow stromal cells. Plasma treated samples showed increased initial cell attachment, indicating the importance of hydrophilicity for cell attachment. However, incorporation only of HA or plasma treatment alone was not sufficient to result in upregulated alkaline phosphatase activity (ALP) activity. Combining HA loaded fibers with plasma treatment showed a combined effect, leading to increased cell attachment and upregulated ALP activity. Based on these results, combination of HA loaded UHMWPE fibers and plasma treatment provided the most promising fabric surface for facilitating bone ingrowth., (© 2022 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials published by Wiley Periodicals LLC.)
- Published
- 2023
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7. Characterization of the virulence, agr typing and antimicrobial resistance profile of Staphylococcus aureus strains isolated from food handlers in Brazil.
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Pereira GDN, Rosa RDS, Dias AA, Gonçalves DJS, Seribelli AA, Pinheiro-Hubinger L, Eller LKW, de Carvalho TB, and Pereira VC
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- Anti-Bacterial Agents pharmacology, Brazil, Clarithromycin, Drug Resistance, Bacterial genetics, Enterotoxins genetics, Humans, Microbial Sensitivity Tests, Penicillins, Staphylococcus aureus, Virulence genetics, Virulence Factors genetics, Methicillin-Resistant Staphylococcus aureus, Staphylococcal Infections epidemiology
- Abstract
Staphylococcus aureus is one of the main pathogens associated with foodborne outbreaks in Brazil and food handlers can carry toxigenic and resistant S. aureus strains. The aims of this study were to verify the frequency of virulence genes, to identify the agr groups and to determine the antimicrobial resistance profile of S. aureus strains isolated from food handlers of pilot kitchens located in São Paulo, Brazil. A total of 74 strains of the Staphylococcus genus were detected and 50% were identified as of the species S. aureus. The enterotoxin genes detection, tst and luk-PV detection, agr typing, mecA detection, ccr complex detection and SCCmec typing were performed using PCR. The antimicrobial resistance testing was performed by the disk diffusion method. The enterotoxin genes were identified in 36 S. aureus, including sea (83.8%). The tst gene was detected in 18.92% of the strains and the luk-PV was detected in only one isolate. Agr typing classified 58.3% of the strains as type I. Seven (18.92%) strains were classified as MRSA and the ccr2 complex was detected in six of these isolates. The SCCmec typing characterized strains as type II, III, IV and V. Moreover, there were also a greater number of resistant strains to penicillin (83.78%) and clarithromycin (67.57%). In conclusion, the study revealed a significant prevalence of S. aureus, and the presence of different virulence genes and a worrying resistance profile in S. aureus strains isolated from food handlers in this country., Competing Interests: Conflicts of interest The authors declare no have conflicts of interest., (Copyright © 2022 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)
- Published
- 2022
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8. The Type I Interferon Pathway Is Upregulated in the Cutaneous Lesions and Blood of Multibacillary Leprosy Patients With Erythema Nodosum Leprosum.
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Rosa TLSA, Mendes MA, Linhares NRC, Rodrigues TF, Dias AA, Leal-Calvo T, Gandini M, Ferreira H, Costa FDMR, Sales AM, Amadeu TP, Schmitz V, Pinheiro RO, Rodrigues LS, Moraes MO, and Pessolani MCV
- Abstract
In leprosy patients, acute inflammatory episodes, known as erythema nodosum leprosum (ENL), are responsible for high morbidity and tissue damage that occur during the course of Mycobacterium leprae infection. In a previous study, we showed evidence implicating DNA-sensing via TLR9 as an important inflammatory pathway in ENL. A likely important consequence of TLR9 pathway activation is the production of type I interferons (IFN-I) by plasmacytoid dendritic cells (pDCs), also implicated in the pathogenesis of several chronic inflammatory diseases. In this study, we investigated whether the IFN-I pathway is activated during ENL. Blood samples and skin lesions from multibacillary patients diagnosed with ENL were collected and the expression of genes of the IFN-I pathway and interferon-stimulated genes were compared with samples collected from non-reactional multibacillary (NR) patients. Whole blood RNAseq analysis suggested higher activation of the IFN-I pathway in ENL patients, confirmed by RT-qPCR. Likewise, significantly higher mRNA levels of IFN-I-related genes were detected in ENL skin biopsies when compared to NR patient lesions. During thalidomide administration, the drug of choice for ENL treatment, a decrease in the mRNA and protein levels of some of these genes both in the skin and blood was observed. Indeed, in vitro assays showed that thalidomide was able to block the secretion of IFN-I by peripheral blood mononuclear cells in response to M. leprae sonicate or CpG-A, a TLR9 ligand. Finally, the decreased frequencies of peripheral pDCs in ENL patients, along with the higher TLR9 expression in ENL pDCs and the enrichment of CD123
+ cells in ENL skin lesions, suggest the involvement of these cells as IFN-I producers in this type of reaction. Taken together, our data point to the involvement of the pDC/type I IFN pathway in the pathogenesis of ENL, opening new avenues in identifying biomarkers for early diagnosis and new therapeutic targets for the better management of this reactional episode., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Rosa, Mendes, Linhares, Rodrigues, Dias, Leal-Calvo, Gandini, Ferreira, Costa, Sales, Amadeu, Schmitz, Pinheiro, Rodrigues, Moraes and Pessolani.)- Published
- 2022
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9. 3D-printed electrochemical platform with multi-purpose carbon black sensing electrodes.
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Silva-Neto HA, Dias AA, and Coltro WKT
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- Electrodes, Printing, Three-Dimensional, Reproducibility of Results, Dielectric Spectroscopy, Soot
- Abstract
The 3D printing is described of a complete and portable system comprising a batch injection analysis (BIA) cell and an electrochemical platform with eight sensing electrodes. Both BIA and electrochemical cells were printed within 3.4 h using a multimaterial printer equipped with insulating, flexible, and conductive filaments at cost of ca. ~ U$ 1.2 per unit, and their integration was based on a threadable assembling without commercial component requirements. Printed electrodes were exposed to electrochemical/Fenton pre-treatments to improve the sensitivity. Scanning electron microscopy and electrochemical impedance spectroscopy measurements upon printed materials revealed high-fidelity 3D features (90 to 98%) and fast heterogeneous rate constants ((1.5 ± 0.1) × 10
-3 cm s-1 ). Operational parameters of BIA cell were optimized using a redox probe composed of [Fe(CN)6 ]4-/3- under stirring and the best analytical performance was achieved using a dispensing rate of 9.0 µL s-1 and an injection volume of 2.0 µL. The proof of concept of the printed device for bioanalytical applications was evaluated using adrenaline (ADR) as target analyte and its redox activities were carefully evaluated through different voltammetric techniques upon multiple 3D-printed electrodes. The coupling of BIA system with amperometric detection ensured fast responses with well-defined peak width related to the oxidation of ADR applying a potential of 0.4 V vs Ag. The fully 3D-printed system provided suitable analytical performance in terms of repeatability and reproducibility (RSD ≤ 6%), linear concentration range (5 to 40 µmol L-1 ; R2 = 0.99), limit of detection (0.61 µmol L-1 ), and high analytical frequency (494 ± 13 h-1 ). Lastly, artificial urine samples were spiked with ADR solutions at three different concentration levels and the obtained recovery values ranged from 87 to 118%, thus demonstrating potentiality for biological fluid analysis. Based on the analytical performance, the complete device fully printed through additive manufacturing technology emerges as powerful, inexpensive, and portable tool for electroanalytical applications involving biologically relevant compounds., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)- Published
- 2022
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10. Solid-State Fermentation of Chestnut Shells and Effect of Explanatory Variables in Predictive Saccharification Models.
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Pinto PA, Bezerra RMF, Fraga I, Amaral C, Sampaio A, and Dias AA
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- Fermentation, Hydrolysis, Sugars, Laccase, Trametes
- Abstract
In this study, chestnut shells (CNS), a recalcitrant and low-value agro-industrial waste obtained during the peeling of Castanea sativa fruits, were subjected to solid-state fermentation by six white-rot fungal strains (Irpex lacteus, Ganoderma resinaceum, Phlebia rufa, Bjerkandera adusta and two Trametes isolates). After being fermented, CNS was subjected to hydrolysis by a commercial enzymatic mix to evaluate the effect of fermentation in saccharification yield. After 48 h hydrolysis with 10 CMCase U mL−1 enzymatic mix, CNS fermented with both Trametes strains was recorded with higher saccharification yield (around 253 mg g−1 fermented CNS), representing 25% w/w increase in reducing sugars as compared to non-fermented controls. To clarify the relationships and general mechanisms of fungal fermentation and its impacts on substrate saccharification, the effects of some independent or explanatory variables in the production of reducing sugars were estimated by general predictive saccharification models. The variables considered were lignocellulolytic activities in fungal fermentation, CNS hydrolysis time, and concentration of enzymatic hydrolysis mix. Multiple linear regression analysis revealed a very high significant effect (p < 0.0001) of fungal laccase and xylanase activities in the saccharification models, thus proving the key potential of these enzymes in CNS solid-state fermentation.
- Published
- 2022
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11. Analysis of human tissues using Energy Dispersive X Ray Fluorescence - Dark matrix determination for the application to cancer research.
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Ensina A, Carvalho PM, Machado J, Carvalho ML, Casal D, Pais D, Santos JP, Dias AA, and Pessanha S
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- Calibration, Female, Humans, Male, Ovary, Spectrometry, X-Ray Emission, X-Rays, Neoplasms, Trace Elements analysis
- Abstract
Background: X ray Fluorescence has been essayed as a suitable technique for the elemental quantification of trace element in human tissues, namely comparison of normal and cancerous tissue. However, accurate results depend on a robust quantification approach, namely correct evaluation of the samples' dark matrix., Methods: In order to determine the most suitable dark matrix composition for the quantification of such samples using the Fundamental Parameter approach, we have measured several Certified Reference Materials and essayed different dark matrix compositions to achieve the most accurate results. The resulting dark matrix was then applied to normal and tumor ovarian and prostate tissue samples, and the obtained results were compared with the ones obtained with a comparative method using external standard calibration curves., Results: Using a dark matrix composed of 10 % - H, 22 % - C, 3 % - N and 60 % - O yielded the best compromise in accuracy for the light and heavy elements. For the reduced sample size and conditions of this study, for both organs, the concentrations of transition metals decrease in tumor tissues, while the concentration of lighter elements, P and Cl, increases. On the other hand, there are elements that showed different behavior between the two types of tissue, namely Zn and S, that increase in prostate tumor tissue and decrease in ovarian tissue., Conclusion: An increase in precision was one of the improvements found with the newly developed method, as the FP-approach contemplates matrix effects and the influence of other elements in the analytes' quantification. Additionally, the determined dark matrix can be employed in any tissue analysis application by means of EDXRF., (Copyright © 2021 Elsevier GmbH. All rights reserved.)
- Published
- 2021
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12. Yellow fever vaccine protects mice against Zika virus infection.
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Vicente Santos AC, Guedes-da-Silva FH, Dumard CH, Ferreira VNS, da Costa IPS, Machado RA, Barros-Aragão FGQ, Neris RLS, Dos-Santos JS, Assunção-Miranda I, Figueiredo CP, Dias AA, Gomes AMO, de Matos Guedes HL, Oliveira AC, and Silva JL
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- Animals, Antibodies, Viral immunology, Chlorocebus aethiops, Disease Models, Animal, Female, Humans, Immunity, Cellular, Interferon-gamma immunology, Mice, Mice, Inbred BALB C, T-Lymphocytes immunology, Vaccination, Vero Cells, Yellow Fever virology, Yellow fever virus genetics, Yellow fever virus immunology, Zika Virus genetics, Zika Virus immunology, Zika Virus Infection immunology, Zika Virus Infection virology, Yellow Fever Vaccine administration & dosage, Zika Virus physiology, Zika Virus Infection prevention & control
- Abstract
Zika virus (ZIKV) emerged as an important infectious disease agent in Brazil in 2016. Infection usually leads to mild symptoms, but severe congenital neurological disorders and Guillain-Barré syndrome have been reported following ZIKV exposure. Creating an effective vaccine against ZIKV is a public health priority. We describe the protective effect of an already licensed attenuated yellow fever vaccine (YFV, 17DD) in type-I interferon receptor knockout mice (A129) and immunocompetent BALB/c and SV-129 (A129 background) mice infected with ZIKV. YFV vaccination provided protection against ZIKV, with decreased mortality in A129 mice, a reduction in the cerebral viral load in all mice, and weight loss prevention in BALB/c mice. The A129 mice that were challenged two and three weeks after the first dose of the vaccine were fully protected, whereas partial protection was observed five weeks after vaccination. In all cases, the YFV vaccine provoked a substantial decrease in the cerebral viral load. YFV immunization also prevented hippocampal synapse loss and microgliosis in ZIKV-infected mice. Our vaccine model is T cell-dependent, with AG129 mice being unable to tolerate immunization (vaccination is lethal in this mouse model), indicating the importance of IFN-γ in immunogenicity. To confirm the role of T cells, we immunized nude mice that we demonstrated to be very susceptible to infection. Immunization with YFV and challenge 7 days after booster did not protect nude mice in terms of weight loss and showed partial protection in the survival curve. When we evaluated the humoral response, the vaccine elicited significant antibody titers against ZIKV; however, it showed no neutralizing activity in vitro and in vivo. The data indicate that a cell-mediated response promotes protection against cerebral infection, which is crucial to vaccine protection, and it appears to not necessarily require a humoral response. This protective effect can also be attributed to innate factors, but more studies are needed to strengthen this hypothesis. Our findings open the way to using an available and inexpensive vaccine for large-scale immunization in the event of a ZIKV outbreak., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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13. TLR-9 Plays a Role in Mycobacterium leprae -Induced Innate Immune Activation of A549 Alveolar Epithelial Cells.
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Dias AA, Silva CAME, da Silva CO, Linhares NRC, Santos JPS, Vivarini AC, Marques MÂM, Rosa PS, Lopes UG, Berrêdo-Pinho M, and Pessolani MCV
- Subjects
- A549 Cells, Biomarkers, Cells, Cultured, Histones metabolism, Host-Pathogen Interactions immunology, Humans, Immunomodulation, Leprosy microbiology, NF-kappa B metabolism, Alveolar Epithelial Cells immunology, Alveolar Epithelial Cells metabolism, Immunity, Innate, Leprosy immunology, Leprosy metabolism, Mycobacterium leprae immunology, Toll-Like Receptor 9 metabolism
- Abstract
The respiratory tract is considered the main port of entry of Mycobacterium leprae , the causative agent of leprosy. However, the great majority of individuals exposed to the leprosy bacillus will never manifest the disease due to their capacity to develop protective immunity. Besides acting as a physical barrier, airway epithelium cells are recognized as key players by initiating a local innate immune response that orchestrates subsequent adaptive immunity to control airborne infections. However, to date, studies exploring the interaction of M. leprae with the respiratory epithelium have been scarce. In this work, the capacity of M. leprae to immune activate human alveolar epithelial cells was investigated, demonstrating that M. leprae -infected A549 cells secrete significantly increased IL-8 that is dependent on NF-κB activation. M. leprae was also able to induce IL-8 production in human primary nasal epithelial cells. M. leprae -treated A549 cells also showed higher expression levels of human β-defensin-2 (hβD-2), MCP-1, MHC-II and the co-stimulatory molecule CD80. Furthermore, the TLR-9 antagonist inhibited both the secretion of IL-8 and NF-κB activation in response to M. leprae , indicating that bacterial DNA sensing by this Toll-like receptor constitutes an important innate immune pathway activated by the pathogen. Finally, evidence is presented suggesting that extracellular DNA molecules anchored to Hlp, a histone-like protein present on the M. leprae surface, constitute major TLR-9 ligands triggering this pathway. The ability of M. leprae to immune activate respiratory epithelial cells herein demonstrated may represent a very early event during infection that could possibly be essential to the generation of a protective response., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Dias, Silva, Silva, Linhares, Santos, Vivarini, Marques, Rosa, Lopes, Berrêdo-Pinho and Pessolani.)
- Published
- 2021
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14. Removal pattern of vinasse phenolics by Phlebia rufa, characterization of an induced laccase and inhibition kinetics modeling.
- Author
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Fernandes JMC, Fraga I, Bezerra RMF, and Dias AA
- Subjects
- Biodegradation, Environmental, Hydrogen-Ion Concentration, Kinetics, Polyporales, Temperature, Laccase metabolism
- Abstract
Vinasse from the distillation of winemaking residues is a wastewater characterized by high levels of aromatic compounds. Batch cultures of Phlebia rufa showed a significant (p < 0.05) correlation between laccase activity and initial vinasse concentration. The pattern of biodegradation of hydroxybenzoic acids, hydroxycinnamic acids and flavonoids, assessed by HPLC-DAD, revealed that p-hydroxybenzoic acid is the most recalcitrant compound. Vinasse-induced laccase showed electrophoretic homogeneity and molecular weight of 62 kDa after being purified 21-fold. Optimum pH for oxidation of 2,6-dimethoxyphenol (2,6-DMP) was 3.5 and optimum temperature was 50 °C, with an activation energy of 42.8 kJ mol
-1 . Catalytic efficiency of 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) oxidation is about two orders of magnitude higher than 2,6-DMP oxidation, being their Km values 36.2 ± 2.6 μM and 303.0 ± 44.7 μM, respectively and kcat values 486.1 s-1 and 179.6 s-1 , respectively. Akaike information criterion and Akaike weights were used to discriminate inhibition models that best fitted 2,6-DMP oxidation in the presence of inhibitors. Inhibition constants of mixed-type inhibitors azide and fluoride, and competitive-type inhibitor chloride, showed the following inhibitors potency: azide > fluoride > chloride. Taken together, this study is consistent with the assumption that P. rufa could be a useful tool for aerobic degradation of phenolic-rich wastewaters.- Published
- 2021
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15. Forest restoration methods, seasonality, and penetration resistance does not influence aboveground biomass stock on mining tailings in Mariana, Brazil.
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Campanharo ÍF, Martins SV, Villa PM, Kruschewsky GC, Dias AA, and Nabeta F
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- Biomass, Brazil, Environmental Monitoring, Forests, Mining, Structure Collapse
- Abstract
The restoration methods applied on the areas affected by the Fundão tailings dam collapse have a high priority in Mariana region. We evaluated the effect of different restoration methods and site preparation techniques, depth and seasonality on penetration resistance of tailings, and how these predictors affect tree aboveground biomass in areas affected by the Fundão dam collapse in Mariana, Brazil. No significant differences in penetration resistance and aboveground biomass between treatments were observed, but significant differences were observed between seasonal periods. The main univariate model explained the significant effects of depth and seasonality, mainly by a negatively wet effect on penetration resistance. According to the best models (univariate and multivariate) were those that had depth as a predictor. This study showed how penetration resistance can be an indicator to select the best period for restoration process in areas affected by the collapse of the Fundão dam, but no limit to the aboveground biomass recovery on tailing.
- Published
- 2021
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16. Teaching Basic Life Support to schoolchildren: quasi-experimental study.
- Author
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Tony ACC, Carbogim FDC, Motta DS, Santos KBD, Dias AA, and Paiva ADCPC
- Subjects
- Adult, Child, Health Education, Health Knowledge, Attitudes, Practice, Humans, Students, Cardiopulmonary Resuscitation, Heart Arrest therapy
- Abstract
Objective: to evaluate the knowledge of basic education students before and after educational intervention on Basic Life Support in a situation of adult cardiorespiratory arrest., Method: quasi-experimental study conducted with 335 students from three elementary schools. Data was collected using an instrument that captured sociodemographic data and knowledge about Basic Life Support. Subsequently, they were analyzed by descriptive and analytical statistics., Results: students' knowledge in the post-test (p <0.05) was significantly higher than in the pre-test. The average of the pre-test scores was 4.12 ± 1.7 and, in the post-test it was 6.53 ± 1.9 (p = 0.00)., Conclusion: the results demonstrated effectiveness of the intervention with the expansion of knowledge about Basic Life Support in cardiorespiratory arrest. The results reinforce the importance of Nursing in health education actions in elementary schools.
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- 2020
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17. Pretreatment of Grape Stalks by Fungi: Effect on Bioactive Compounds, Fiber Composition, Saccharification Kinetics and Monosaccharides Ratio.
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Fernandes JMC, Fraga I, Sousa RMOF, Rodrigues MAM, Sampaio A, Bezerra RMF, and Dias AA
- Subjects
- Biomass, Carbohydrates, Fermentation, Kinetics, Lignin metabolism, Vitis metabolism, Monosaccharides, Vitis microbiology
- Abstract
Grape stalks, an inedible lignocellulosic residue from winemaking and agro-industrial grape juice production, can be valorized as a source of bioactive compounds and as feedstock for the saccharification and bioconversion of soluble sugars. Solid-state fermentation (SSF) by six white-rot fungi was applied as pretreatment. Fiber composition, free radical scavenging activity, four ligninolytic, and three hydrolytic enzyme activities were determined. Saccharification kinetics, yield, and productivity were evaluated and complemented with scanning electron microscopy (SEM), high performance liquid chromatography (HPLC) quantification of monosaccharides, and principal component analysis (PCA). After SSF, the biomass exhibited a drastic free radical scavenging activity decrease and the main enzymes produced were manganese-dependent peroxidase and xylanase. Scanning electron microscopy revealed the erosion of cell walls, and PCA exhibited a negative correlation between saccharification, and neutral detergent fiber and acid detergent lignin. Phlebia rufa pretreated biomass gave the highest sugars yield and productivity, representing a nearly three-fold increase compared to untreated samples. Also, monosaccharides quantification revealed that the 1:1 ratio of glucose to the sum of xylose plus galactose changes to the value of 2:1 after pretreatment. In this work, and for the first time, P. rufa proved to be an effective pretreatment of grape stalks for the saccharification and further bioconversion into value-added chemicals. In addition, lignocellulolytic enzymes were also produced through SSF.
- Published
- 2020
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18. A Kinetic Process to Determine the Interaction Type Between Two Compounds, One of Which Is a Reaction Product, Using Alkaline Phosphatase Inhibition as a Case Study.
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Bezerra RMF, Pinto PA, and Dias AA
- Subjects
- Binding, Competitive, Drug Interactions, Kinetics, Models, Chemical, Phosphates antagonists & inhibitors, Urea antagonists & inhibitors, Alkaline Phosphatase drug effects, Enzyme Inhibitors pharmacology
- Abstract
This study describes the development of a new methodology based on a new integrated equation which allows the determination of the kinetic parameters for two mutually non-exclusive inhibitors when one of which is produced during the time-course reaction. Alkaline phosphatase simultaneously inhibited by phosphate and urea is used to illustrate this methodology, including the evaluation of interaction effects between them. Data analyses were carried out using two integrated velocity equations: exclusive linear mixed inhibition (EMI) and non-exclusive linear mixed inhibition (NEMI). Kinetic parameters are estimated using non-linear regression and results show that (i) the interaction between enzyme and the inhibitors urea and phosphate exhibit a mutually non-exclusive behavior; (ii) more specifically, these inhibitors are non-exclusive only in free enzyme (E) species; (iii) the inhibitors also show an interaction with enzyme classified as facilitation; (iv) phosphate is a competitive inhibitor and urea a mixed inhibitor; (v) the inhibition constant for phosphate is much lower than that determined for urea. In addition, a functional Excel Spreadsheet which can be adapted to any kinetic study is also included as a supplement.
- Published
- 2020
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19. Covid-19 in the State of Ceará: behaviors and beliefs in the arrival of the pandemic.
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Lima DLF, Dias AA, Rabelo RS, Cruz IDD, Costa SC, Nigri FMN, and Neri JR
- Subjects
- Betacoronavirus, Brazil epidemiology, COVID-19, Educational Status, Female, Humans, Public Health, Quarantine, SARS-CoV-2, Social Isolation, Surveys and Questionnaires, Survival, Coronavirus Infections epidemiology, Health Knowledge, Attitudes, Practice, Pandemics, Pneumonia, Viral epidemiology
- Abstract
This study aimed to evaluate the behavioral aspects and beliefs of the population of Ceará in the face of the COVID-19 pandemic. An online questionnaire was conducted on sociodemographic aspects and opinions related to the pandemic. Absolute and relative frequencies were calculated, the association between variables was performed with Chi-square, and the level of significance was 5%. The final sample had 2,259 participants, and an association was observed between females and perceiving themselves with a high risk of infection (p = 0.044) and males with non-performance of voluntary quarantine (p < 0.001). People aged 80 years and over were partially quarantined due to the flow of people at home (p < 0.001). Participants with elementary school education had a lower risk of infection than participants with a higher level of education (p < 0.001). This group includes people who did voluntary quarantine the least (p < 0.001). Participants living in the inland region of the state had less direct contact with someone tested positive for the Coronavirus (p = 0.031) and are less reclusive (p < 0.001). We can conclude that the approach to the COVID-19 pandemic varies by social aspects, such as gender, age, education, and place of residence, as well as the belief system of the population of the State of Ceará.
- Published
- 2020
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20. The novel ghrelin receptor inverse agonist PF-5190457 administered with alcohol: preclinical safety experiments and a phase 1b human laboratory study.
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Lee MR, Tapocik JD, Ghareeb M, Schwandt ML, Dias AA, Le AN, Cobbina E, Farinelli LA, Bouhlal S, Farokhnia M, Heilig M, Akhlaghi F, and Leggio L
- Subjects
- Adult, Alcohol Drinking drug therapy, Alcohol Drinking metabolism, Alcoholism drug therapy, Alcoholism metabolism, Animals, Azetidines metabolism, Azetidines pharmacokinetics, Ethanol chemistry, Female, Ghrelin metabolism, Humans, Male, Middle Aged, Rats, Rats, Wistar, Receptors, Ghrelin metabolism, Research Design, Single-Blind Method, Spiro Compounds metabolism, Spiro Compounds pharmacokinetics, Alcoholic Intoxication drug therapy, Azetidines pharmacology, Receptors, Ghrelin agonists, Spiro Compounds pharmacology
- Abstract
Rodent studies indicate that ghrelin receptor blockade reduces alcohol consumption. However, no ghrelin receptor blockers have been administered to heavy alcohol drinking individuals. Therefore, we evaluated the safety, tolerability, pharmacokinetic (PK), pharmacodynamic (PD) and behavioral effects of a novel ghrelin receptor inverse agonist, PF-5190457, when co-administered with alcohol. We tested the effects of PF-5190457 combined with alcohol on locomotor activity, loss-of-righting reflex (a measure of alcohol sedative actions), and on blood PF-5190457 concentrations in rats. Then, we performed a single-blind, placebo-controlled, within-subject human study with PF-5190457 (placebo/0 mg b.i.d., 50 mg b.i.d., 100 mg b.i.d.). Twelve heavy drinkers during three identical visits completed an alcohol administration session, subjective assessments, and an alcohol cue-reactivity procedure, and gave blood samples for PK/PD testing. In rats, PF-5190457 did not interact with the effects of alcohol on locomotor activity or loss-of-righting reflex. Alcohol did not affect blood PF-5190457 concentrations. In humans, all adverse events were mild or moderate and did not require discontinuation or dose reductions. Drug dose did not alter alcohol concentration or elimination, alcohol-induced stimulation or sedation, or mood during alcohol administration. Potential PD markers of PF-5190457 were acyl-to-total ghrelin ratio and insulin-like growth factor-1. PF-5190457 (100 mg b.i.d.) reduced alcohol craving during the cue-reactivity procedure. This study provides the first translational evidence of safety and tolerability of the ghrelin receptor inverse agonist PF-5190457 when co-administered with alcohol. PK/PD/behavioral findings support continued research of PF-5190457 as a potential pharmacological agent to treat alcohol use disorder.
- Published
- 2020
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21. Congenital Zika syndrome is associated with maternal protein malnutrition.
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Barbeito-Andrés J, Pezzuto P, Higa LM, Dias AA, Vasconcelos JM, Santos TMP, Ferreira JCCG, Ferreira RO, Dutra FF, Rossi AD, Barbosa RV, Amorim CKN, De Souza MPC, Chimelli L, Aguiar RS, Gonzalez PN, Lara FA, Castro MC, Molnár Z, Lopes RT, Bozza MT, Vianez JLSG, Barbeito CG, Cuervo P, Bellio M, Tanuri A, and Garcez PP
- Subjects
- Animals, Animals, Newborn, Body Weight, Brain enzymology, Brain pathology, Brazil epidemiology, Diet, Protein-Restricted, Disease Outbreaks, Embryo, Mammalian pathology, Female, Gene Expression Regulation, Developmental, Malnutrition virology, Mice, Inbred C57BL, Microcephaly complications, Microcephaly virology, Neurogenesis, Organ Size, Pregnancy, Syndrome, Viral Load, Zika Virus Infection virology, Malnutrition complications, Zika Virus Infection complications, Zika Virus Infection congenital
- Abstract
Zika virus (ZIKV) infection during pregnancy is associated with a spectrum of developmental impairments known as congenital Zika syndrome (CZS). The prevalence of this syndrome varies across ZIKV endemic regions, suggesting that its occurrence could depend on cofactors. Here, we evaluate the relevance of protein malnutrition for the emergence of CZS. Epidemiological data from the ZIKV outbreak in the Americas suggest a relationship between undernutrition and cases of microcephaly. To experimentally examine this relationship, we use immunocompetent pregnant mice, which were subjected to protein malnutrition and infected with a Brazilian ZIKV strain. We found that the combination of protein restriction and ZIKV infection leads to severe alterations of placental structure and embryonic body growth, with offspring displaying a reduction in neurogenesis and postnatal brain size. RNA-seq analysis reveals gene expression deregulation required for brain development in infected low-protein progeny. These results suggest that maternal protein malnutrition increases susceptibility to CZS., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)
- Published
- 2020
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22. Fungal biodegradation and multi-level toxicity assessment of vinasse from distillation of winemaking by-products.
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Fernandes JMC, Sousa RMOF, Fraga I, Sampaio A, Amaral C, Bezerra RMF, and Dias AA
- Subjects
- Aliivibrio fischeri metabolism, Animals, Biodegradation, Environmental, Daphnia metabolism, Distillation, Environmental Biomarkers drug effects, Laccase metabolism, Lepidium sativum metabolism, Peroxidases metabolism, Phenols metabolism, Phylogeny, Aliivibrio fischeri growth & development, Coriolaceae metabolism, Daphnia growth & development, Lepidium sativum growth & development, Polyporales metabolism, Trametes metabolism, Wastewater chemistry, Wastewater toxicity
- Abstract
The wastewaters from distilleries of winemaking by-products, a scarcely studied type of vinasse, were treated by white-rot fungal strains from species Irpex lacteus, Ganoderma resinaceum, Trametes versicolor, Phlebia rufa and Bjerkandera adusta. The main objectives of this study were to evaluate fungal performance during vinasse biodegradation, their enzyme patterns and ecotoxicity evolution throughout treatment. Despite all strains were able to promote strong (>80%) dephenolization and reduction of total organic carbon (TOC), P. rufa was less affected by vinasse toxicity and exhibit better decolorization. In batch cultures at 28 °C and pH 4.0, the first phase of P. rufa biodegradation kinetics was characterized by strong metabolic activity with simultaneous depletion of TOC, phenolics and sugars. The main events of second phase are the increase of peroxidases production after the peak of laccase activity, and strong color removal. At the end of treatment, it was observed highly significant (p < 0.001) abatement of pollution parameters (83-100% removal). Since water reclamation and reuse for e.g. crop irrigation is a priority issue, vinasse ecotoxicity was assessed with bioindicators representing three different phylogenetic and trophic levels: a marine bacterium (Aliivibrio fischeri), a freshwater microcrustacean (Daphnia magna) and a dicotyledonous macrophyte (Lepidium sativum). It was observed significant (p < 0.05) reduction of initial vinasse toxicity, as evaluated by these bioindicators, deserving special mention an almost complete phytotoxicity elimination., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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23. Hazardous impact of vinasse from distilled winemaking by-products in terrestrial plants and aquatic organisms.
- Author
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Sousa RMOF, Amaral C, Fernandes JMC, Fraga I, Semitela S, Braga F, Coimbra AM, Dias AA, Bezerra RM, and Sampaio A
- Subjects
- Animals, Aquatic Organisms growth & development, Germination drug effects, Lethal Dose 50, Organic Chemicals chemistry, Plants classification, Toxicity Tests, Water Pollutants, Chemical chemistry, Aquatic Organisms drug effects, Industrial Waste, Plants drug effects, Water Pollutants, Chemical toxicity, Wine
- Abstract
Vinasses obtained from the distillation of winemaking by-products (WDV) are complex effluents with variable physicochemical properties. Frequently, WDVs are used to irrigate agricultural soil, and/or discharged into aquatic bodies, which may result in serious environmental pollution, due to the presence of organic acids and recalcitrant compounds (polyphenols, tannins and metals). The present study aimed to evaluate the toxicity impact of an untreated WDV on terrestrial and aquatic organisms, at different levels of biological organization. The effluent was collected at the distillation column exit and characterized according to several physicochemical properties. The WDV potential phytotoxicity was assessed by germination inhibition assays on six agricultural crops, and its acute toxicity was assessed on Aliivibrio fisheri (microtox assay), Daphnia magna neonates (freshwater crustacean), and zebrafish Danio rerio (fish embryo toxicity test, FET). The WDV presented a low pH (3.88), high levels of electrical conductivity, ECond (6.36 dS m
-1 ) and salinity (3.3 ppt), besides high level of potassium (2.1 g L-1 ) and organic compounds (TOC = 17.7 g L-1 ), namely polyphenols (1.7 g L-1 ). The diluted WDV displayed variable inhibitory effects on the plant endpoints (percentage of inhibition of germination and radicle elongation and germination index). Overall, plants' susceptibility to increasing concentrations of WDV were differential (onion ≈ garden cress ≥ tomato > lettuce > maize > green beans) and the germination index EC50 varied from 10.9 to 64.4% v/v. Also, the acute negative effects toward aquatic organisms were determined, decreasing from the more complex organism to the simpler one: zebrafish embryos (96 h-LC50 = 0.34% v/v)>D. magna (48 h-LC50 = 4.8% v/v)>A. fisheri (30min-EC50 = 7.0% v/v). In conclusion, the findings suggest that WDVs might have a high toxicological impact on both terrestrial plants and aquatic organisms, even at high dilution levels, reinforcing the need for appropriate treatments before considering its discharge or reuse., (Copyright © 2019 Elsevier Inc. All rights reserved.)- Published
- 2019
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24. Environmentally Friendly Manufacturing of Flexible Graphite Electrodes for a Wearable Device Monitoring Zinc in Sweat.
- Author
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Dias AA, Chagas CLS, Silva-Neto HA, Lobo-Junior EO, Sgobbi LF, de Araujo WR, Paixão TRLC, and Coltro WKT
- Subjects
- Dielectric Spectroscopy, Electrodes, Humans, Limit of Detection, Electrochemical Techniques, Graphite chemistry, Sweat metabolism, Wearable Electronic Devices, Zinc analysis, Zinc metabolism
- Abstract
Electrochemical sensors based on graphite and polymers have emerged as powerful analytical tools for bioanalytical applications. However, most of the fabrication processes are not environmentally friendly because they often involve the use of toxic reagents and generate waste. This study describes an alternative method to produce flexible electrodes in plastic substrates using graphite powder and thermal laminating sheets by solid-solid deposition through hot compression, without the use of hazardous chemical reagents. The electrodes developed through the proposed approach have successfully demonstrated flexibility, robustness, reproducibility (relative standard deviation around 6%), and versatility. The electrodes were thoroughly characterized by cyclic voltammetry, electrochemical impedance spectroscopy, Raman spectroscopy, and scanning electron microscopy. As a proof of concept, the electrode surfaces were modified with bismuth and used for zinc analysis in sweat. The modified electrodes presented linearity ( R
2 = 0.996) for a wide zinc concentration range (50-2000 ppb) and low detection limit (4.31 ppb). The proposed electrodes were tested using real sweat samples and the achieved zinc concentrations did not differ statistically from the data obtained by atomic absorption spectroscopy. To allow wearable applications, a 3D-printed device was fabricated, integrated with the proposed electrochemical system, and fixed at the abdomen by using an elastic tape to collect, store, and analyze the sweat sample. The matrix effect test was performed, spiking the real sample with different zinc levels, and the recovery values varied between 85 and 106%, thus demonstrating adequate accuracy and robustness of the flexible electrodes developed based on the proposed fabrication method.- Published
- 2019
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25. Neutrophil extracellular traps contribute to the pathogenesis of leprosy type 2 reactions.
- Author
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da Silva CO, Dias AA, da Costa Nery JA, de Miranda Machado A, Ferreira H, Rodrigues TF, Sousa Santos JP, Nadaes NR, Sarno EN, Saraiva EM, Schmitz V, and Pessolani MCV
- Subjects
- Adult, Aged, Aged, 80 and over, Autoimmune Diseases immunology, Autoimmune Diseases microbiology, Female, Humans, Inflammation immunology, Inflammation pathology, Leprosy drug therapy, Leprosy pathology, Male, Middle Aged, Mycobacterium leprae immunology, Mycobacterium leprae pathogenicity, Neutrophils pathology, Thalidomide administration & dosage, Thalidomide therapeutic use, Extracellular Traps immunology, Immunity, Innate, Leprosy immunology
- Abstract
Up to 50% of patients with the multibacillary form of leprosy are expected to develop acute systemic inflammatory episodes known as type 2 reactions (T2R), thus aggravating their clinical status. Thalidomide rapidly improves T2R symptoms. But, due to its restricted use worldwide, novel alternative therapies are urgently needed. The T2R triggering mechanisms and immune-inflammatory pathways involved in its pathology remain ill defined. In a recent report, we defined the recognition of nucleic acids by TLR9 as a major innate immunity pathway that is activated during T2R. DNA recognition has been described as a major inflammatory pathway in several autoimmune diseases, and neutrophil DNA extracellular traps (NETs) have been shown to be a prime source of endogenous DNA. Considering that neutrophil abundance is a marked characteristic of T2R lesions, the objective of this study was to investigate NETs production in T2R patients based on the hypothesis that the excessive NETs formation would play a major role in T2R pathogenesis. Abundant NETs were found in T2R skin lesions, and increased spontaneous NETs formation was observed in T2R peripheral neutrophils. Both the M. leprae whole-cell sonicate and the CpG-Hlp complex, mimicking a mycobacterial TLR9 ligand, were able to induce NETs production in vitro. Moreover, TLR9 expression was shown to be higher in T2R neutrophils, suggesting that DNA recognition via TLR9 may be one of the pathways triggering this process during T2R. Finally, treatment of T2R patients with thalidomide for 7 consecutive days resulted in a decrease in all of the evaluated in vivo and ex vivo NETosis parameters. Altogether, our findings shed light on the pathogenesis of T2R, which, it is hoped, will contribute to the emergence of novel alternative therapies and the identification of prognostic reactional markers in the near future., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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26. Batch injection analysis towards auxiliary diagnosis of periodontal diseases based on indirect amperometric detection of salivary α-amylase on a cupric oxide electrode.
- Author
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Garcia PT, Dias AA, Souza JAC, and Coltro WKT
- Subjects
- Case-Control Studies, Chronic Disease, Electrodes, Glucose chemistry, Glucose metabolism, Humans, Limit of Detection, Maltose chemistry, Maltose metabolism, Periodontal Diseases metabolism, Reproducibility of Results, Saliva enzymology, Salivary alpha-Amylases metabolism, Copper chemistry, Electrochemical Techniques, Periodontal Diseases diagnosis, Salivary alpha-Amylases analysis
- Abstract
This study describes, for the first time, the use of a batch injection analysis system with amperometric detection (BIA-AD) to indirectly determine salivary α-amylase (sAA) levels in saliva samples for chronic periodontitis diagnosis. A chemical/thermal treatment was explored to generate a CuO film on a Cu electrode surface. This procedure offered good stability (RSD = 0.3%), good repeatability (RSD < 1.3%) and excellent reproducibility (RSD < 1.5%). The sAA concentration levels were determined based on the detection of maltose produced by enzymatic hydrolysis of starch. The analytical performance was investigated, and a linear correlation was observed for a maltose concentration range between 0.5 and 6.0 mmol L
-1 with a correlation coefficient equal to 0.999. The analytical sensitivity and the limit of detection were 48.8 μA/(mmol L-1 ) and 0.05 mmol L-1 , respectively. In addition, the proposed system provided an excellent analytical frequency (120 analysis h-1 ). The clinical feasibility of the proposed method was investigated by the determination of sAA levels in four saliva samples (two from healthy control persons (C1 and C2) and two from patients with chronic periodontitis (P1 and P2)). The accuracy provided by the BIA-AD system ranged from 93 to 98%. The sAA concentration levels achieved for each sample were compared to the values found by spectrophotometry and there was no statistically significant difference between them at a confidence level of 95%. Finally, the method reported herein emerges as a simple, low cost and promising tool for assisting periodontal diseases diagnosis., (Copyright © 2018 Elsevier B.V. All rights reserved.)- Published
- 2018
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27. Mediterranean forested wetlands are yeast hotspots for bioremediation: a case study using azo dyes.
- Author
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Sampaio AC, Bezerra RMF, and Dias AA
- Subjects
- Basidiomycota classification, Basidiomycota isolation & purification, Biomass, Cluster Analysis, Ecosystem, Phylogeny, Wetlands, Azo Compounds metabolism, Basidiomycota metabolism, Biodegradation, Environmental
- Abstract
Forested wetlands are interfaces between terrestrial and aquatic environments. These ecosystems play an important role in the hydrology, chemistry and biodiversity maintenance. Despite their high microbial diversity, there has been a lack of attention to the potential of their yeast communities. The purpose of this study is to evaluate the potential of yeasts isolated from a Mediterranean forested wetlands in decolorizing azo dyes. Azo dyes are synthetic, and highly recalcitrant to degradation. Ninety-two out of 560 isolates were randomly chosen to assess their ability to decolorize five azo dyes. Hierarchical clustering based on medium color changes during incubations was used to evaluate the isolates' decolorization performance. All of the isolates that best degraded the 5 dyes tested were identified as Basidiomycota (Filobasidiales, Tremellales and Sporidiobolales). This work identifies new azo dye-degrading yeast species, and supports the hypothesis that forested wetlands are a niche for yeasts with bioremediation potential - namely azo dyes removal.
- Published
- 2018
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28. Zika virus impairs the development of blood vessels in a mouse model of congenital infection.
- Author
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Garcez PP, Stolp HB, Sravanam S, Christoff RR, Ferreira JCCG, Dias AA, Pezzuto P, Higa LM, Barbeito-Andrés J, Ferreira RO, Andrade CBV, Siqueira M, Santos TMP, Drumond J, Hoerder-Suabedissen A, de Lima CVF, Tovar-Moll F, Lopes RT, Fragel-Madeira L, Lent R, Ortiga-Carvalho TM, Stipursky J, Bellio M, Tanuri A, and Molnár Z
- Subjects
- Animals, Blood Vessels pathology, Brain blood supply, Brain pathology, Brain virology, Disease Models, Animal, Embryo, Mammalian pathology, Embryo, Mammalian virology, Endothelial Cells pathology, Endothelial Cells virology, Female, Mice, Inbred C57BL, Neurogenesis, Organ Size, Zika Virus Infection pathology, Zika Virus Infection virology, Neovascularization, Physiologic, Zika Virus physiology, Zika Virus Infection congenital
- Abstract
Zika virus (ZIKV) is associated with brain development abnormalities such as primary microcephaly, a severe reduction in brain growth. Here we demonstrated in vivo the impact of congenital ZIKV infection in blood vessel development, a crucial step in organogenesis. ZIKV was injected intravenously in the pregnant type 2 interferon (IFN)-deficient mouse at embryonic day (E) 12.5. The embryos were collected at E15.5 and postnatal day (P)2. Immunohistochemistry for cortical progenitors and neuronal markers at E15.5 showed the reduction of both populations as a result of ZIKV infection. Using confocal 3D imaging, we found that ZIKV infected brain sections displayed a reduction in the vasculature density and vessel branching compared to mocks at E15.5; altogether, cortical vessels presented a comparatively immature pattern in the infected tissue. These impaired vascular patterns were also apparent in the placenta and retina. Moreover, proteomic analysis has shown that angiogenesis proteins are deregulated in the infected brains compared to controls. At P2, the cortical size and brain weight were reduced in comparison to mock-infected animals. In sum, our results indicate that ZIKV impairs angiogenesis in addition to neurogenesis during development. The vasculature defects represent a limitation for general brain growth but also could regulate neurogenesis directly.
- Published
- 2018
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29. Effects of Dental Occlusion on Body Sway, Upper Body Muscle Activity and Shooting Performance in Pistol Shooters.
- Author
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Dias AA, Redinha LA, Silva LM, and Pezarat-Correia PC
- Abstract
Occlusal splints, to some extent, have been related to reduced body sway in a static position and increased muscle activity in the upper limbs. However, how dental occlusion status affects sports performance remains unclear. Here, we investigated whether occlusal splints that reposition the temporomandibular joint (TMJ) influenced body posture, muscle activity, and performance in 10-meter pistol shooters. Thirteen national-level male shooters (age = 38.8 ± 10.9 yrs) were recruited for this study, and cleared of any cervical pathology. An occlusal splint (OS) and a placebo splint (PS) were fabricated for each of the subjects, with the mandibular and maxillary position verified by an expert dentist, with the aid of an adjustable articulator. Surface electromyography (EMG) was assessed in the upper limb that holds the pistol while the subjects were standing on a force platform. Subjects performed two series of 10 shots for each of the three experimental conditions (OS, PS, N (no splint)) in randomized order, with the mandible in a rest position. Results revealed similar centre of pressure (COP) parameters in all conditions, despite a reduction in the average oscillation area caused by the OS. There were also no significant differences in EMG activity between conditions in the five upper limb muscles monitored. Consistent with this, shooting performance was similar in all conditions, despite a reduction in shot dispersion in subjects using OS. Thus, changes in dental occlusion status induced by OS do not affect body posture, upper limb EMG muscle activity, or shot performance in healthy male pistol shooters.
- Published
- 2018
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30. PGL I expression in live bacteria allows activation of a CD206/PPARγ cross-talk that may contribute to successful Mycobacterium leprae colonization of peripheral nerves.
- Author
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Díaz Acosta CC, Dias AA, Rosa TLSA, Batista-Silva LR, Rosa PS, Toledo-Pinto TG, Costa FDMR, Lara FA, Rodrigues LS, Mattos KA, Sarno EN, Bozza PT, Guilhot C, de Berrêdo-Pinho M, and Pessolani MCV
- Subjects
- Humans, Mannose Receptor, Mycobacterium leprae metabolism, Receptor Cross-Talk physiology, Antigens, Bacterial metabolism, Glycolipids metabolism, Lectins, C-Type metabolism, Leprosy metabolism, Mannose-Binding Lectins metabolism, PPAR gamma metabolism, Receptors, Cell Surface metabolism, Schwann Cells virology
- Abstract
Mycobacterium leprae, an obligate intracellular bacillus, infects Schwann cells (SCs), leading to peripheral nerve damage, the most severe leprosy symptom. In the present study, we revisited the involvement of phenolic glycolipid I (PGL I), an abundant, private, surface M. leprae molecule, in M. leprae-SC interaction by using a recombinant strain of M. bovis BCG engineered to express this glycolipid. We demonstrate that PGL I is essential for bacterial adhesion and SC internalization. We also show that live mycobacterium-producing PGL I induces the expression of the endocytic mannose receptor (MR/CD206) in infected cells in a peroxisome proliferator-activated receptor gamma (PPARγ)-dependent manner. Of note, blocking mannose recognition decreased bacterial entry and survival, pointing to a role for this alternative recognition pathway in bacterial pathogenesis in the nerve. Moreover, an active crosstalk between CD206 and the nuclear receptor PPARγ was detected that led to the induction of lipid droplets (LDs) formation and prostaglandin E2 (PGE2), previously described as fundamental players in bacterial pathogenesis. Finally, this pathway was shown to induce IL-8 secretion. Altogether, our study provides evidence that the entry of live M. leprae through PGL I recognition modulates the SC phenotype, favoring intracellular bacterial persistence with the concomitant secretion of inflammatory mediators that may ultimately be involved in neuroinflammation., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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31. Vaccination With Recombinant Filamentous fd Phages Against Parasite Infection Requires TLR9 Expression.
- Author
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Gomes-Neto JF, Sartorius R, Canto FB, Almeida TS, Dias AA, Barbosa CD, Melo GA, Oliveira AC, Aguiar PN, Machado CR, de Matos Guedes HL, Santiago MF, Nóbrega A, De Berardinis P, and Bellio M
- Subjects
- Animals, Mice, Mice, Knockout, Bacteriophage M13 genetics, Bacteriophage M13 immunology, Chagas Disease genetics, Chagas Disease immunology, Chagas Disease prevention & control, Gene Expression Regulation drug effects, Gene Expression Regulation immunology, Protozoan Vaccines genetics, Protozoan Vaccines immunology, Protozoan Vaccines pharmacology, Toll-Like Receptor 9 genetics, Toll-Like Receptor 9 immunology, Trypanosoma cruzi genetics, Trypanosoma cruzi immunology, Vaccination
- Abstract
Recombinant filamentous fd bacteriophages (r fd ) expressing antigenic peptides were shown to induce cell-mediated immune responses in the absence of added adjuvant, being a promising delivery system for vaccination. Here, we tested the capacity of r fd phages to protect against infection with the human protozoan Trypanosoma cruzi , the etiologic agent of Chagas Disease. For this, C57BL/6 (B6) and Tlr9
- / - mice were vaccinated with r fd phages expressing the OVA257-264 peptide or the T. cruzi -immunodominant peptides PA8 and TSKB20 and challenged with either the T. cruzi Y-OVA or Y-strain, respectively. We found that vaccination with r fd phages induces anti-PA8 and anti-TSKB20 IgG production, expansion of Ag-specific IFN-γ, TNF-α, and Granzyme B-producing CD8+ T cells, as well as in vivo Ag-specific cytotoxic responses. Moreover, the fd -TSKB20 vaccine was able to protect against mortality induced by a high-dose inoculum of the parasite. Although vaccination with r fd phages successfully reduced both parasitemia and parasite load in the myocardium of WT B6 mice, Tlr9-/- animals were not protected against infection. Thus, our data extend previous studies, demonstrating that r fd phages induce Ag-specific IgG and CD8+ T cell-mediated responses and confer protection against an important human parasite infection, through a TLR9-dependent mechanism.- Published
- 2018
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32. Polypeptide Polymer Brushes by Light-Induced Surface Polymerization of Amino Acid N-Carboxyanhydrides.
- Author
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Stukenkemper T, Paquez X, Verhoeven MWGM, Hensen EJM, Dias AA, Brougham DF, and Heise A
- Subjects
- Mass Spectrometry, Photoelectron Spectroscopy, Polyglutamic Acid chemical synthesis, Polyglutamic Acid chemistry, Amino Acids chemistry, Carbamates chemical synthesis, Polyglutamic Acid analogs & derivatives, Ultraviolet Rays
- Abstract
Silicon wafers are decorated with photoamine generator 4,5-dimethoxy-2-nitrobenzyl 3-(triethoxysilyl)propyl carbamate. UV-irradiation in the presence of benzyl-l-glutamate N-carboxyanhydride is carried out, resulting in the release of the surface-bound primary amines, making them viable N-carboxyanhydride (NCA) polymerization initiators. Successful polypeptide grafting is confirmed by water contact angle measurements as well as by ellipsometry, revealing a poly(benzyl-l-glutamate) (PBLG) layer of ≈3 nm. X-ray photoelectron spectroscopy confirms the presence of amide groups in the grafted PBLG while time-of-flight secondary ion mass spectroscopy provides additional evidence for the presence of PBLG on the surface. Evaluation of negative control samples confirms successful UV surface grafting. The approach is thus established as a viable general method for light exposure directable polypeptide functionalization of silicon surfaces., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2018
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33. Innate Immune Responses in Leprosy.
- Author
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Pinheiro RO, Schmitz V, Silva BJA, Dias AA, de Souza BJ, de Mattos Barbosa MG, de Almeida Esquenazi D, Pessolani MCV, and Sarno EN
- Subjects
- Animals, Humans, Leprosy pathology, Leprosy transmission, Mycobacterium leprae physiology, Immunity, Innate, Leprosy immunology
- Abstract
Leprosy is an infectious disease that may present different clinical forms depending on host immune response to Mycobacterium leprae . Several studies have clarified the role of various T cell populations in leprosy; however, recent evidences suggest that local innate immune mechanisms are key determinants in driving the disease to its different clinical manifestations. Leprosy is an ideal model to study the immunoregulatory role of innate immune molecules and its interaction with nervous system, which can affect homeostasis and contribute to the development of inflammatory episodes during the course of the disease. Macrophages, dendritic cells, neutrophils, and keratinocytes are the major cell populations studied and the comprehension of the complex networking created by cytokine release, lipid and iron metabolism, as well as antimicrobial effector pathways might provide data that will help in the development of new strategies for leprosy management.
- Published
- 2018
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34. Determination of Ascorbic Acid in Commercial Tablets Using Pencil Drawn Electrochemical Paper-based Analytical Devices.
- Author
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Oliveira VXG, Dias AA, Carvalho LL, Cardoso TMG, Colmati F, and Coltro WKT
- Subjects
- Ascorbic Acid chemistry, Electrodes, Graphite chemistry, Ascorbic Acid analysis, Electrochemistry instrumentation, Paper
- Abstract
This study describes the use of electrochemical paper-based analytical devices (ePADs) drawn with graphite pencil for the determination of ascorbic acid (AA) in commercial tablets. ePADs were fabricated using vegetal paper and graphite pencil. First, the three-electrode electrochemical cell drawn using a graphical software and toner lines were laser printed on the vegetal paper surface to delimit the electrode areas. Then, the electrode regions were manually painted with graphite pencil. Afterwards, the pseudo-reference electrode was defined with the deposition of silver ink over the graphite surface. Cyclic voltammetry and square wave voltammetry (SWV) experiments were performed to optimize the electroanalytical parameters as well as to quantitatively determine the AA concentration in two commercial tables. ePADs exhibited linear behavior for a concentration range between 0.5 and 3.0 mmol L
-1 . The achieved limit of detection and sensitivity were 70 μmol L-1 and 0.47 μA/mmol L-1 , respectively. The AA concentration levels found by SWV experiments in both CenevitTM and Energil CTM were 2.80 ± 0.02 and 3.10 ± 0.01 mmol L-1 , respectively. The accuracy of the proposed devices was investigated through recovery experiments in three concentration levels and it presented values between 95 and 115%.- Published
- 2018
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35. Exploring Tyrosine-Triazolinedione (TAD) Reactions for the Selective Conjugation and Cross-Linking of N-Carboxyanhydride (NCA) Derived Synthetic Copolypeptides.
- Author
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Hanay SB, Ritzen B, Brougham D, Dias AA, and Heise A
- Subjects
- Peptides chemical synthesis, Peptides chemistry, Triazines chemistry, Tyrosine chemistry
- Abstract
Highly efficient functionalization and cross-linking of polypeptides is achieved via tyrosine-triazolinedione (TAD) conjugation chemistry. The feasibility of the reaction is demonstrated by the reaction of 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) with tyrosine containing block copolymer poly(ethylene glycol)-Tyr
4 as well as a statistical copolymer of tyrosine and lysine (poly(Lys40 -st-Tyr10 )) prepared form N-carboxyanhydride polymerization. Selective reaction of PTAD with the tyrosine units is obtained and verified by size exclusion chromatography and NMR spectroscopy. Moreover, two monofunctional and two difunctional TAD molecules are synthesized. It is found that their stability in the aqueous reaction media significantly varied. Under optimized reaction conditions selective functionalization and cross-linking, yielding polypeptide hydrogels, can be achieved. TAD-mediated conjugation can offer an interesting addition in the toolbox of selective (click-like) polypeptide conjugation methodologies as it does not require functional non-natural amino acids., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2017
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36. Evaluation of polyesteramide (PEA) and polyester (PLGA) microspheres as intravitreal drug delivery systems in albino rats.
- Author
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Peters T, Kim SW, Castro V, Stingl K, Strasser T, Bolz S, Schraermeyer U, Mihov G, Zong M, Andres-Guerrero V, Herrero Vanrell R, Dias AA, Cameron NR, and Zrenner E
- Subjects
- Albinism, Oculocutaneous, Amides adverse effects, Animals, Capsules administration & dosage, Capsules adverse effects, Dexamethasone adverse effects, Diffusion, Intravitreal Injections methods, Lactic Acid adverse effects, Male, Materials Testing, Microspheres, Polyesters adverse effects, Polyglycolic Acid adverse effects, Polylactic Acid-Polyglycolic Acid Copolymer, Rats, Rats, Sprague-Dawley, Retina drug effects, Amides chemistry, Capsules chemistry, Dexamethasone administration & dosage, Lactic Acid chemistry, Polyesters chemistry, Polyglycolic Acid chemistry, Retina anatomy & histology, Retina physiology
- Abstract
Purpose: To study the suitability of injectable microspheres based on poly(ester amide) (PEA) or poly lactic-co-glycolic acid (PLGA) as potential vehicles for intravitreal drug delivery in rat eyes. Dexamethasone-loaded PEA microspheres (PEA + DEX) were also evaluated., Methods: Forty male Sprague Dawley rats were divided into four groups that received different intravitreally injected microspheres: PEA group (n = 12); PLGA group (n = 12); PEA + DEX group (n = 8); and control group (no injection, n = 8). Electroretinography (ERG), fundus autofluorescence (FAF), and spectral domain optical coherence tomography (sdOCT) were performed at baseline, weeks 1 and 2, and months 1, 2, and 3 after intravitreal injection. Eyes were histologically examined using light microscopy and transmission electron microscopy at the end of the in vivo study., Results: There were no statistically significant changes in ERG among the groups. Abnormal FAF pattern and abnormal deposits in OCT were observed after injection but almost completely disappeared between week 2 and month 3 in all injected groups. GFAP staining showed that Müller glia cell activation was most pronounced in PLGA-injected eyes. Increased cell death was not observed by TUNEL staining at month 1. In electron microscopy at month 3, the remnants of microparticles were found in the retinal cells of all injected groups, and loss of plasma membrane was seen in the PLGA group., Conclusions: Although morphological changes such as mild glial activation and material remnants were observed histologically 1 month and 3 months after injection in all injected groups, minor cell damage was noted only in the PLGA group at 3 months after injection. No evidence of functional abnormality relative to untreated eyes could be detected by ERG 3 months after injection in all groups. Changes observed in in vivo imaging such as OCT and FAF disappeared after 3 months in almost all cases., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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37. Chloroquine, an Endocytosis Blocking Agent, Inhibits Zika Virus Infection in Different Cell Models.
- Author
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Delvecchio R, Higa LM, Pezzuto P, Valadão AL, Garcez PP, Monteiro FL, Loiola EC, Dias AA, Silva FJ, Aliota MT, Caine EA, Osorio JE, Bellio M, O'Connor DH, Rehen S, de Aguiar RS, Savarino A, Campanati L, and Tanuri A
- Subjects
- Animals, Cell Line, Chlorocebus aethiops, Humans, Mice, Antiviral Agents pharmacology, Chloroquine pharmacology, Endocytosis drug effects, Zika Virus drug effects, Zika Virus physiology, Zika Virus Infection virology
- Abstract
Zika virus (ZIKV) infection in utero might lead to microcephaly and other congenital defects. Since no specific therapy is available thus far, there is an urgent need for the discovery of agents capable of inhibiting its viral replication and deleterious effects. Chloroquine is widely used as an antimalarial drug, anti-inflammatory agent, and it also shows antiviral activity against several viruses. Here we show that chloroquine exhibits antiviral activity against ZIKV in Vero cells, human brain microvascular endothelial cells, human neural stem cells, and mouse neurospheres. We demonstrate that chloroquine reduces the number of ZIKV-infected cells in vitro, and inhibits virus production and cell death promoted by ZIKV infection without cytotoxic effects. In addition, chloroquine treatment partially reveres morphological changes induced by ZIKV infection in mouse neurospheres., Competing Interests: The authors declare no conflict of interest.
- Published
- 2016
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38. Pathogenic properties of a Corynebacterium diphtheriae strain isolated from a case of osteomyelitis.
- Author
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Peixoto RS, Hacker E, Antunes CA, Weerasekera D, Dias AA, Martins CA, Hirata R Jr, Santos KRND, Burkovski A, and Mattos-Guaraldi AL
- Subjects
- Adult, Animals, Caenorhabditis elegans, Corynebacterium diphtheriae classification, Corynebacterium diphtheriae genetics, Epithelial Cells microbiology, Female, Humans, Macrophages microbiology, Male, Mice, RAW 264.7 Cells, Virulence, Corynebacterium diphtheriae isolation & purification, Corynebacterium diphtheriae pathogenicity, Osteomyelitis microbiology
- Abstract
Corynebacterium diphtheriae is typically recognized as a colonizer of the upper respiratory tract (respiratory diphtheria) and the skin (cutaneous diphtheria). However, different strains of Corynebacteriumdiphtheriae can also cause invasive infections. In this study, the characterization of a non-toxigenic Corynebacteriumdiphtheriae strain (designated BR-INCA5015) isolated from osteomyelitis in the frontal bone of a patient with adenoid cystic carcinoma was performed. Pathogenic properties of the strain BR-INCA5015 were tested in a Caenorhabditis elegans survival assay showing strong colonization and killing by this strain. Survival rates of 3.8±2.7 %, 33.6±7.3 % and 0 % were observed for strains ATCC 27010T, ATCC 27012 and BR-INCA5015, respectively, at day 7. BR-INCA5015 was able to colonize epithelial cells, showing elevated capacity to adhere to and survive within HeLa cells compared to other Corynebacteriumdiphtheriae isolates. Intracellular survival in macrophages (THP-1 and RAW 264.7) was significantly higher compared to control strains ATCC 27010T (non-toxigenic) and ATCC 27012 (toxigenic). Furthermore, the ability of BR-INCA5015 to induce osteomyelitis was confirmed by in vivo assay using Swiss Webster mice.
- Published
- 2016
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39. DNA Sensing via TLR-9 Constitutes a Major Innate Immunity Pathway Activated during Erythema Nodosum Leprosum.
- Author
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Dias AA, Silva CO, Santos JP, Batista-Silva LR, Acosta CC, Fontes AN, Pinheiro RO, Lara FA, Machado AM, Nery JA, Sarno EN, Pereira GM, and Pessolani MC
- Subjects
- Adult, Aged, Aged, 80 and over, Erythema Nodosum microbiology, Female, Flow Cytometry, Humans, Leprosy, Lepromatous microbiology, Leukocytes, Mononuclear immunology, Leukocytes, Mononuclear microbiology, Male, Middle Aged, Mycobacterium leprae chemistry, Mycobacterium leprae immunology, Toll-Like Receptor 9 immunology, Young Adult, DNA metabolism, Erythema Nodosum immunology, Immunity, Innate, Leprosy, Lepromatous immunology, Signal Transduction, Toll-Like Receptor 9 metabolism
- Abstract
The chronic course of lepromatous leprosy may be interrupted by acute inflammatory episodes known as erythema nodosum leprosum (ENL). Despite its being a major cause of peripheral nerve damage in leprosy patients, the immunopathogenesis of ENL remains ill-defined. Recognized by distinct families of germline-encoded pattern recognition receptors, endogenous and pathogen-derived nucleic acids are highly immunostimulatory molecules that play a major role in the host defense against infections, autoimmunity, and autoinflammation. The aim of this work was to investigate whether DNA sensing via TLR-9 constitutes a major inflammatory pathway during ENL. Flow cytometry and immunohistochemistry analysis showed significantly higher TLR-9 expression in ENL when compared with nonreactional lepromatous patients, both locally in the skin lesions and in circulating mononuclear cells. The levels of endogenous and pathogen-derived TLR-9 ligands in the circulation of ENL patients were also higher. Furthermore, PBMCs isolated from the ENL patients secreted higher levels of TNF, IL-6, and IL-1β in response to a TLR-9 agonist than those of the nonreactional patients and healthy individuals. Finally, E6446, a TLR-9 synthetic antagonist, was able to significantly inhibit the secretion of proinflammatory cytokines by ENL PBMCs in response to Mycobacterium leprae lysate. Our data strongly indicate that DNA sensing via TLR-9 constitutes a major innate immunity pathway involved in the pathogenesis and evolution of ENL. Thus, the use of TLR-9 antagonists emerges as a potential alternative to more effectively treat ENL aiming to prevent the development of nerve injuries and deformities in leprosy., (Copyright © 2016 by The American Association of Immunologists, Inc.)
- Published
- 2016
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40. A MLST Clade 2 Clostridium difficile strain with a variant TcdB induces severe inflammatory and oxidative response associated with mucosal disruption.
- Author
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Costa CL, López-Ureña D, de Oliveira Assis T, Ribeiro RA, Silva RO, Rupnik M, Wilcox MH, de Carvalho AF, do Carmo AO, Dias AA, de Carvalho CB, Chaves-Olarte E, Rodríguez C, Quesada-Gómez C, and de Castro Brito GA
- Subjects
- Adult, Animals, Anti-Bacterial Agents pharmacology, Bacterial Proteins metabolism, Bacterial Toxins metabolism, Clostridioides difficile classification, Clostridioides difficile drug effects, Clostridioides difficile genetics, Diarrhea complications, Diarrhea microbiology, Disease Models, Animal, Enterocolitis, Pseudomembranous complications, Enterocolitis, Pseudomembranous drug therapy, Enterocolitis, Pseudomembranous microbiology, Female, Gene Expression, Humans, Intestinal Mucosa microbiology, Intestinal Mucosa pathology, Male, Mice, Multilocus Sequence Typing, Neoplasms complications, Neoplasms microbiology, Oxidative Stress, Phylogeny, Polymerase Chain Reaction, Ribotyping, Bacterial Proteins genetics, Bacterial Toxins genetics, Clostridioides difficile isolation & purification, Diarrhea diagnosis, Enterocolitis, Pseudomembranous diagnosis, Neoplasms diagnosis
- Abstract
The epidemiology of Clostridium difficile infections is highly dynamic as new strains continue to emerge worldwide. Here we present a detailed analysis of a new C. difficile strain (ICC-45) recovered from a cancer patient in Brazil that died from severe diarrhea. A polyphasic approach assigned a new PCR-ribotype and PFGE macrorestriction pattern to strain ICC-45, which is toxigenic (tcdA(+), tcdB(+) and ctdB(+)) and classified as ST41 from MLST Clade 2 and toxinotype IXb. Strain ICC-45 encodes for a variant TcdB that induces a distinct CPE in agreement with its toxinotype. Unlike epidemic NAP1/027 strains, which are also classified to MLST Clade 2, strain ICC-45 is susceptible to fluoroquinolones and does not overproduce toxins TcdA and TcdB. However, supernatants from strain ICC-45 and a NAP1/027 strain produced similar expression of pro-inflammatory cytokines, epithelial damage, and oxidative stress response in the mouse ileal loop model. These results highlight inflammation and oxidative stress as common features in the pathogenesis of C. difficile Clade 2 strains. Finally, this work contributes to the description of differences in virulence among various C. difficile strains., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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41. Quantitative determinations and imaging in different structures of buried human bones from the XVIII-XIXth centuries by energy dispersive X-ray fluorescence - Postmortem evaluation.
- Author
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Guimarães D, Dias AA, Carvalho M, Carvalho ML, Santos JP, Henriques FR, Curate F, and Pessanha S
- Subjects
- Archaeology, Autopsy, Humans, Limit of Detection, Bone and Bones chemistry, Bone and Bones diagnostic imaging, Molecular Imaging, Spectrometry, X-Ray Emission
- Abstract
In this work, a non-commercial triaxial geometry energy dispersive X-ray Fluorescence (EDXRF) setup and a benchtop µ-XRF system were used to identify postmortem contamination in buried bones. For two of the individuals, unusually high concentrations of Cu and Pb, but also Zn (in one individual) were observed. The pigments of the burial shroud coverings have been identified as the source of contamination. Accurate and precise quantitative results were obtained by nondestructive process using fundamental parameters method taking into account the matrix absorption effects. A total of 30 bones from 13 individuals, buried between the mid-XVIIIth to early XIXth centuries, were analyzed to study the elemental composition and elemental distribution. The bones were collected from a church in Almada (Portugal), called Ermida do Espírito Santo, located near the Tagus River and at the sea neighbourhood. The triaxial geometry setup was used to quantify Ca, Fe, Cu, Zn, Br, Sr and Pb of powder pressed bone pellets (n=9 for each bone). Cluster analysis was performed considering the elemental concentrations for the different bones. There was a clear association between some bones regarding Fe, Cu, Zn, Br and Pb content but not a categorization between cortical and trabecular bones. The elemental distribution of Cu, Zn and Pb were assessed by the benchtop μ-analysis, the M4 Tornado, based on a polycapillary system which provides multi-elemental 2D maps. The results showed that contamination was mostly on the surface of the bone confirming that it was related to the burial shroud covering the individuals., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
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42. A Study of H2O2 with Threshold Photoelectron Spectroscopy (TPES) and Electronic Structure Calculations: Redetermination of the First Adiabatic Ionization Energy (AIE).
- Author
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Schio L, Alagia M, Dias AA, Falcinelli S, Zhaunerchyk V, Lee EP, Mok DK, Dyke JM, and Stranges S
- Abstract
In this work, hydrogen peroxide has been studied with threshold photoelectron (TPE) spectroscopy and photoelectron (PE) spectroscopy. The TPE spectrum has been recorded in the 10.0-21.0 eV ionization energy region, and the PE spectrum has been recorded at 21.22 eV photon energy. Five bands have been observed which have been assigned on the basis of UCCSD(T)-F12/VQZ-F12 and IP-EOM CCSD calculations. Vibrational structure has only been resolved in the TPE spectrum of the first band, associated with the X̃(2)Bg H2O2(+) ← X̃(1)A H2O2 ionization, on its low energy side. This structure is assigned with the help of harmonic Franck-Condon factor calculations that use the UCCSD(T)-F12a/VQZ-F12 computed adiabatic ionization energy (AIE), and UCCSD(T)-F12a/VQZ-F12 computed equilibrium geometric parameters and harmonic vibrational frequencies for the H2O2 X̃(1)A state and the H2O2(+) X̃(2)Bg state. These calculations show that the main vibrational structure on the leading edge of the first TPE band is in the O-O stretching mode (ω3) and the HOOH deformation mode (ω4), and comparison of the simulated spectrum to the experimental spectrum gives the first AIE of H2O2 as (10.685 ± 0.005) eV and ω4 = (850 ± 30) and ω3 = (1340 ± 30) cm(-1) in the X̃(2)Bg state of H2O2(+). Contributions from ionization of vibrationally excited levels in the torsion mode have been identified in the TPE spectrum of the first band and the need for a vibrationally resolved TPE spectrum from vibrationally cooled molecules, as well as higher level Franck-Condon factors than performed in this work, is emphasized.
- Published
- 2016
- Full Text
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43. Mycobacterium leprae-induced Insulin-like Growth Factor I attenuates antimicrobial mechanisms, promoting bacterial survival in macrophages.
- Author
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Batista-Silva LR, Rodrigues LS, Vivarini Ade C, Costa Fda M, Mattos KA, Costa MR, Rosa PS, Toledo-Pinto TG, Dias AA, Moura DF, Sarno EN, Lopes UG, and Pessolani MC
- Subjects
- Adult, Animals, Cell Line, Female, Humans, Insulin-Like Growth Factor I genetics, Janus Kinases metabolism, Leprosy microbiology, Macrophages microbiology, Male, Mice, STAT1 Transcription Factor metabolism, Insulin-Like Growth Factor I metabolism, Leprosy immunology, Macrophages immunology, Mycobacterium leprae pathogenicity
- Abstract
Mycobacterium leprae (ML), the etiologic agent of leprosy, can subvert macrophage antimicrobial activity by mechanisms that remain only partially understood. In the present study, the participation of hormone insulin-like growth factor I (IGF-I) in this phenomenum was investigated. Macrophages from the dermal lesions of the disseminated multibacillary lepromatous form (LL) of leprosy expressed higher levels of IGF-I than those from the self-limited paucibacillary tuberculoid form (BT). Higher levels of IGF-I secretion by ML-infected macrophages were confirmed in ex vivo and in vitro studies. Of note, the dampening of IGF-I signaling reverted the capacity of ML-infected human and murine macrophages to produce antimicrobial molecules and promoted bacterial killing. Moreover, IGF-I was shown to inhibit the JAK/STAT1-dependent signaling pathways triggered by both mycobacteria and IFN-γ most probably through its capacity to induce the suppressor of cytokine signaling-3 (SOCS3). Finally, these in vitro findings were corroborated by in vivo observations in which higher SOCS3 expression and lower phosphorylation of STAT1 levels were found in LL versus BT dermal lesions. Altogether, our data strongly suggest that IGF-I contributes to the maintenance of a functional program in infected macrophages that suits ML persistence in the host, reinforcing a key role for IGF-I in leprosy pathogenesis.
- Published
- 2016
- Full Text
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44. Enzyme inhibition studies by integrated Michaelis-Menten equation considering simultaneous presence of two inhibitors when one of them is a reaction product.
- Author
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Bezerra RM, Pinto PA, Fraga I, and Dias AA
- Subjects
- Catalysis, Kinetics, Enzyme Inhibitors chemistry
- Abstract
To determine initial velocities of enzyme catalyzed reactions without theoretical errors it is necessary to consider the use of the integrated Michaelis-Menten equation. When the reaction product is an inhibitor, this approach is particularly important. Nevertheless, kinetic studies usually involved the evaluation of other inhibitors beyond the reaction product. The occurrence of these situations emphasizes the importance of extending the integrated Michaelis-Menten equation, assuming the simultaneous presence of more than one inhibitor because reaction product is always present. This methodology is illustrated with the reaction catalyzed by alkaline phosphatase inhibited by phosphate (reaction product, inhibitor 1) and urea (inhibitor 2). The approach is explained in a step by step manner using an Excel spreadsheet (available as a template in Appendix). Curve fitting by nonlinear regression was performed with the Solver add-in (Microsoft Office Excel). Discrimination of the kinetic models was carried out based on Akaike information criterion. This work presents a methodology that can be used to develop an automated process, to discriminate in real time the inhibition type and kinetic constants as data (product vs. time) are achieved by the spectrophotometer., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2016
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45. Effect of Functionally Significant Deiodinase Single Nucleotide Polymorphisms on Drinking Behavior in Alcohol Dependence: An Exploratory Investigation.
- Author
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Lee MR, Schwandt ML, Bollinger JW, Dias AA, Oot EN, Goldman D, Hodgkinson CA, and Leggio L
- Subjects
- Adult, Alcohol Drinking genetics, Alcohol Drinking psychology, Alcoholism diagnosis, Alcoholism psychology, Female, Humans, Male, Middle Aged, Young Adult, Alcoholism genetics, Iodide Peroxidase genetics, Polymorphism, Single Nucleotide genetics
- Abstract
Background: Abnormalities of the hypothalamic-pituitary-thyroid (HPT) axis have been reported in alcoholism; however, there is no definitive agreement on the specific thyroid abnormalities and their underlying mechanisms in alcohol dependence. The biological activity of thyroid hormones or the availability of T3 is regulated by the three deiodinase enzymes: D1, D2, and D3. In the context of alcohol use, functionally significant single nucleotide polymorphisms (SNPs) of these deiodinase genes may play a role in HPT dysfunction., Methods: This study explored the effect of three functionally significant SNPs (D1: rs2235544, D2: rs225014, and rs12885300) of deiodinase genes on drinking behavior and thyroid-stimulating hormone (TSH) levels in alcohol-dependent (N = 521) and control subjects (N = 288)., Results: Rs225014 was associated with significant differences in the amount of naturalistic alcohol drinking assessed by Timeline Follow Back. Alcohol-dependent subjects had significantly higher TSH levels compared to controls; however, there was no effect of genotype on TSH levels for either group., Conclusions: These findings extend previous studies on thyroid dysfunction in alcoholism and provide novel, albeit preliminary, information by linking functionally significant genetic polymorphisms of the deiodinase enzymes with alcohol-drinking behavior., (Copyright © 2015 by the Research Society on Alcoholism.)
- Published
- 2015
- Full Text
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46. Reply to "Comment on 'The Mechanism of Pyrolysis of Benzyl Azide: Spectroscopic Evidence for Benzemethanimine Formation'".
- Author
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Pinto RM, Guerra M, Costa ML, and Dias AA
- Published
- 2015
- Full Text
- View/download PDF
47. Reductively degradable α-amino acid-based poly(ester amide)-graft-galactose copolymers: facile synthesis, self-assembly, and hepatoma-targeting doxorubicin delivery.
- Author
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Lv J, Sun H, Zou Y, Meng F, Dias AA, Hendriks M, Feijen J, and Zhong Z
- Subjects
- Antineoplastic Agents metabolism, Antineoplastic Agents pharmacology, Asialoglycoprotein Receptor metabolism, Carcinoma, Hepatocellular chemistry, Carcinoma, Hepatocellular metabolism, Doxorubicin administration & dosage, Doxorubicin metabolism, Doxorubicin pharmacology, Drug Carriers chemistry, Drug Delivery Systems, Drug Liberation, Galactose chemistry, Hep G2 Cells, Humans, MCF-7 Cells, Micelles, Phenylalanine pharmacology, Polymers chemistry, Asialoglycoprotein Receptor chemistry, Carcinoma, Hepatocellular drug therapy, Doxorubicin chemistry, Drug Carriers administration & dosage, Galactose pharmacology, Nanoparticles chemistry, Phenylalanine chemistry, Polyamines chemistry, Polyesters chemistry, Polymers pharmacology
- Abstract
Novel reductively degradable α-amino acid-based poly(ester amide)-graft-galactose (SSPEA-Gal) copolymers were designed and developed to form smart nano-vehicles for active hepatoma-targeting doxorubicin (DOX) delivery. SSPEA-Gal copolymers were readily synthesized via solution polycondensation reaction of di-p-toluenesulfonic acid salts of bis-l-phenylalanine 2,2-thiodiethanol diester and bis-vinyl sulfone functionalized cysteine hexanediol diester with dinitrophenyl ester of adipic acid, followed by conjugating with thiol-functionalized galactose (Gal-SH) via the Michael addition reaction. SSPEA-Gal formed unimodal nanoparticles (PDI = 0.10 - 0.12) in water, in which average particle sizes decreased from 138 to 91 nm with increasing Gal contents from 31.6 wt% to 42.5 wt%. Notably, in vitro drug release studies showed that over 80% DOX was released from SSPEA-Gal nanoparticles within 12 h under an intracellular mimicking reductive conditions, while low DOX release (<20%) was observed for reduction-insensitive PEA-Gal nanoparticles under otherwise the same conditions and SSPEA-Gal nanoparticles under non-reductive conditions. Notably, SSPEA-Gal nanoparticles exhibited high specificity to asialoglycoprotein receptor (ASGP-R)-overexpressing HepG2 cells. MTT assays using HepG2 cells showed that DOX-loaded SSPEA-Gal had a low half maximal inhibitory concentration (IC50) of 1.37 μg mL(-1), approaching that of free DOX. Flow cytometry and confocal laser scanning microscopy studies confirmed the efficient uptake of DOX-loaded SSPEA-Gal nanoparticles by HepG2 cells as well as fast intracellular DOX release. Importantly, SSPEA-Gal and PEA-Gal nanoparticles were non-cytotoxic to HepG2 and MCF-7 cells up to a tested concentration of 1.0 mg mL(-1). These tumor-targeting and reduction-responsive degradable nanoparticles have appeared as an interesting multi-functional platform for advanced drug delivery.
- Published
- 2015
- Full Text
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48. [Psychiatry and criminology in Criminal Justice: Jury Trial Courts and Appellate Courts in the Federal District of Rio de Janeiro, during the 1930s].
- Author
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Dias AA
- Subjects
- Brazil, Criminal Law history, Criminal Law legislation & jurisprudence, History, 20th Century, Humans, Criminology history, Psychiatry history
- Abstract
As part of a research study on the 1930s and 1940s medical-criminological debate in Brazil, this research paper analyzes some of the uses and criticisms of arguments of a psychiatric and criminological nature, among certain jurists who carried out important work in the city of Rio de Janeiro during the 1930s. In this context, these magistrates, tended to have significant psychiatric and criminological knowledge, in spite of all the heterogeneity, plurality and differences in perspectives that existed among them. We selected two principal areas to conduct an analysis of the activities of these jurists: the Appellate Court of the Federal District of Rio de Janeiro and Jury Trial Courts.
- Published
- 2015
- Full Text
- View/download PDF
49. The mechanism of pyrolysis of benzyl azide: spectroscopic evidence for benzenemethanimine formation.
- Author
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Pinto RM, Guerra M, Copeland G, Olariu RI, Rodrigues P, Barros MT, Costa ML, and Dias AA
- Abstract
We study the gas-phase pyrolysis of benzyl azide (BA, C6H5CH2N3) using ultraviolet photoelectron spectroscopy (UVPES) and matrix-isolation infrared (IR) spectroscopy, together with electronic structure calculations and Rice-Ramsperger-Kassel-Marcus (RRKM) calculations. It is found that BA decomposes via N2 elimination at ca. 615 K, primarily yielding benzenemethaninime. Other end products include HCN and C6H6. N-Methyleneaniline is not detected, although its formation at higher temperature is foreseen by RRKM calculations.
- Published
- 2015
- Full Text
- View/download PDF
50. Intratumoral heterogeneity of ADAM23 promotes tumor growth and metastasis through LGI4 and nitric oxide signals.
- Author
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Costa ET, Barnabé GF, Li M, Dias AA, Machado TR, Asprino PF, Cavalher FP, Ferreira EN, Del Mar Inda M, Nagai MH, Malnic B, Duarte ML, Leite KR, de Barros AC, Carraro DM, Chammas R, Armelin HA, Cavenee W, Furnari F, and Camargo AA
- Subjects
- ADAM Proteins genetics, Breast Neoplasms genetics, Cell Line, Tumor, Cell Proliferation, DNA Methylation, Epigenesis, Genetic, Extracellular Matrix Proteins genetics, Female, Gene Silencing, Humans, Neoplasm Metastasis, Nerve Tissue Proteins, Tumor Burden, Tumor Microenvironment, ADAM Proteins metabolism, Breast Neoplasms metabolism, Breast Neoplasms pathology, Extracellular Matrix Proteins metabolism, Nitric Oxide metabolism
- Abstract
Intratumoral heterogeneity (ITH) represents an obstacle for cancer diagnosis and treatment, but little is known about its functional role in cancer progression. The A Desintegrin And Metalloproteinase 23 (ADAM23) gene is epigenetically silenced in different types of tumors, and silencing is often associated with advanced disease and metastasis. Here, we show that invasive breast tumors exhibit significant ADAM23-ITH and that this heterogeneity is critical for tumor growth and metastasis. We demonstrate that while loss of ADAM23 expression enhances invasion, it causes a severe proliferative deficiency and is not itself sufficient to trigger metastasis. Rather, we observed that, in ADAM23-heterotypic environments, ADAM23-negative cells promote tumor growth and metastasis by enhancing the proliferation and invasion of adjacent A23-positive cells through the production of LGI4 (Leucine-rich Glioma Inactivated 4) and nitric oxide (NO). Ablation of LGI4 and NO in A23-negative cells significantly attenuates A23-positive cell proliferation and invasion. Our work denotes a driving role of ADAM23-ITH during disease progression, shifting the malignant phenotype from the cellular to the tissue level. Our findings also provide insights for therapeutic intervention, enforcing the need to ascertain ITH to improve cancer diagnosis and therapy.
- Published
- 2015
- Full Text
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