116 results on '"da Silva AD"'
Search Results
2. Post-Kidney Transplant Anemia as a Result of Passenger Lymphocyte Syndrome by Rhesus Antibodies - A Rare Etiology for a Common Finding
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da Silva Ad, La Salete Martins, Manuela Guedes de Almeida, António Cabrita, António Castro Henriques, Dias L, Malheiro J, and S. Pedroso
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medicine.anatomical_structure ,biology ,business.industry ,Anemia ,Lymphocyte ,Immunology ,Etiology ,biology.protein ,Medicine ,Antibody ,business ,medicine.disease ,Kidney transplant - Published
- 2019
3. Modeling COVID-19 in Cape Verde Islands - An application of SIR model
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da Silva Adilson
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covid-19 ,santiago ,boavista ,cape verde ,sir model ,92d30 ,93a30 ,93d99 ,Biotechnology ,TP248.13-248.65 ,Physics ,QC1-999 - Abstract
The rapid and surprised emergence of COVID-19, having infected three million and killed two hundred thousand people worldwide in less than five months, has led many experts to focus on simulating its propagation dynamics in order to have an estimated outlook for the not too distante future and so supporting the local and national governments in making decisions. In this paper, we apply the SIR model to simulating the propagation dynamics of COVID-19 on the Cape Verde Islands. It will be done firstly for Santiago and Boavista Islands, and then for Cape Verde in general. The choice of Santiago rests on the fact that it is the largest island, with more than 50% of the Population of the country, whereas Boavista was chosen because it is the island where the first case of COVID-19 in Cape Verde was diagnosed. Observations made after the date of the simulations were carried out corroborate our projections.
- Published
- 2021
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4. The dynamic of a Lie group endomorphism
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Ayala Víctor, Román-Flores Heriberto, and Da Silva Adriano
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lie group ,dynamic ,endomorphism ,20k30 ,22e15 ,Mathematics ,QA1-939 - Abstract
For a given endomorphism φ on a connected Lie group G this paper studies several subgroups of G that are intrinsically connected with the dynamic behavior of φ.
- Published
- 2017
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5. Synthesis and biological activity of methyl-d-glucopyranoside derivatives of mercaptopurine and mercaptopyrimidine
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Da Silva, AD, primary, Machado, AS, additional, Tempête, C, additional, and Robert-Gero, M, additional
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- 1994
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6. Predictors of HBeAg status and hepatitis B viraemia in HIV-infected patients with chronic hepatitis B in the HAART era in Brazil
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Leite Andréa G, Martins Luiz G, Guastini Cristina F, da Silva Adriana C, Gomes-Gouvea Michele S, Pinho João RR, Mendes-Correa Maria, Silva Mariliza H, Gianini Reinaldo J, and Uip David E
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hepatitis B virus ,HIV ,virological outcome ,tenofovir ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background HBV-HIV co-infection is associated with an increased liver-related morbidity and mortality. However, little is known about the natural history of chronic hepatitis B in HIV-infected individuals under highly active antiretroviral therapy (HAART) receiving at least one of the two drugs that also affect HBV (TDF and LAM). Information about HBeAg status and HBV viremia in HIV/HBV co-infected patients is scarce. The objective of this study was to search for clinical and virological variables associated with HBeAg status and HBV viremia in patients of an HIV/HBV co-infected cohort. Methods A retrospective cross-sectional study was performed, of HBsAg-positive HIV-infected patients in treatment between 1994 and 2007 in two AIDS outpatient clinics located in the São Paulo metropolitan area, Brazil. The baseline data were age, sex, CD4 T+ cell count, ALT level, HIV and HBV viral load, HBV genotype, and duration of antiretroviral use. The variables associated to HBeAg status and HBV viremia were assessed using logistic regression. Results A total of 86 HBsAg patients were included in the study. Of these, 48 (56%) were using combination therapy that included lamivudine (LAM) and tenofovir (TDF), 31 (36%) were using LAM monotherapy, and 7 patients had no previous use of either one. Duration of use of TDF and LAM varied from 4 to 21 and 7 to 144 months, respectively. A total of 42 (48. 9%) patients were HBeAg positive and 44 (51. 1%) were HBeAg negative. The multivariate analysis revealed that the use of TDF for longer than 12 months was associated with undetectable HBV DNA viral load (serum HBV DNA level < 60 UI/ml) (p = 0. 047). HBeAg positivity was associated with HBV DNA > 60 UI/ml (p = 0. 001) and ALT levels above normality (p = 0. 038). Conclusion Prolonged use of TDF containing HAART is associated with undetectable HBV DNA viral load. HBeAg positivity is associated with HBV viremia and increased ALT levels.
- Published
- 2011
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7. Varroa destructor mite population dynamics in africanized honeybee (Apis mellifera) colonies in a semi-arid region.
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da Silva LA, da Silva AD, Domingos HGT, Bergamo GC, Message D, and Gramacho KP
- Abstract
Most published data on mite infestation rates in semi-arid regions have been collected over only 3 or 4 months during a specific period of the year. Therefore, the aim of this study was to observe parasite-host dynamics of hygienic and non-hygienic Africanized bee colonies considering environmental factors that may influence Varroa destructor mite infestation rates in a semi-arid region. To this end, the brood puncture method was applied to 37 colonies, forming two groups, namely G1, encompassing 16 hygienic colonies, and G2, comprising 21 non-hygienic colonies. After forming the groups, 300 worker bees from each colony were examined monthly for mite infestations and the data were correlated with climatological records. The monthly infestation average was considered low, below 10%, except in November, when it reached 12.19% ± 6.45. No statistically significant difference was observed for inter-group infestation rates (P > 0.05). When mite infestation rates were associated with climatic variables, they were linked to colony losses (32%) due to swarming. No significant correlations between hygienic behaviour and parasite infestation rates were noted. Nonetheless, these results support the idea that there is no need to apply acaricides for V. destructor control in Brazil., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
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- 2024
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8. SAnDReS 2.0: Development of machine-learning models to explore the scoring function space.
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de Azevedo WF Jr, Quiroga R, Villarreal MA, da Silveira NJF, Bitencourt-Ferreira G, da Silva AD, Veit-Acosta M, Oliveira PR, Tutone M, Biziukova N, Poroikov V, Tarasova O, and Baud S
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- Ligands, Software, Molecular Docking Simulation, Machine Learning, Proteins chemistry, Proteins metabolism
- Abstract
Classical scoring functions may exhibit low accuracy in determining ligand binding affinity for proteins. The availability of both protein-ligand structures and affinity data make it possible to develop machine-learning models focused on specific protein systems with superior predictive performance. Here, we report a new methodology named SAnDReS that combines AutoDock Vina 1.2 with 54 regression methods available in Scikit-Learn to calculate binding affinity based on protein-ligand structures. This approach allows exploration of the scoring function space. SAnDReS generates machine-learning models based on crystal, docked, and AlphaFold-generated structures. As a proof of concept, we examine the performance of SAnDReS-generated models in three case studies. For all three cases, our models outperformed classical scoring functions. Also, SAnDReS-generated models showed predictive performance close to or better than other machine-learning models such as K
DEEP , CSM-lig, and ΔVina RF20 . SAnDReS 2.0 is available to download at https://github.com/azevedolab/sandres., (© 2024 Wiley Periodicals LLC.)- Published
- 2024
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9. Vitamin D3 mitigates type 2 diabetes induced by a high carbohydrate-high fat diet in rats: Role of the purinergic system.
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Vera Castro MF, Assmann CE, Reichert KP, Coppetti PM, Stefanello N, da Silva AD, Mostardeiro VB, de Jesus LB, da Silveira MV, Schirmann AA, Fracasso M, Maciel RM, Morsch VMM, and Schetinger MRC
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- Rats, Male, Animals, Rats, Wistar, Cholecalciferol pharmacology, Diet, High-Fat adverse effects, Vitamins, Adenosine Monophosphate metabolism, Adenosine Triphosphate metabolism, Diabetes Mellitus, Experimental drug therapy, Diabetes Mellitus, Experimental metabolism, Diabetes Mellitus, Type 2 drug therapy, Insulins
- Abstract
This study evaluated the effect of vitamin D
3 (VIT D3 ) supplementation on the enzymatic activities and density of ectonucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-5-nucleotidase (E-5'-NT), adenosine deaminase (ADA), as well as the density of P2 × 7R, P2Y12R, A1R, A2AR receptors, IL-1β, and oxidative parameters in type 2 diabetic rats. Forty male Wistar rats were fed a high carbohydrate-high fat diet (HCHFD) and received an intraperitoneal injection containing a single dose of streptozotocin (STZ, 35 mg/kg). Animals were divided into four groups: 1) control; 2) control/VIT D3 12 µg/kg; 3) diabetic; and 4) diabetic/VIT D3 12 µg/kg. Results show that VIT D3 reduced blood glucose, ATP hydrolysis, ADA activity, P2Y12R density (platelets), as well as ATP, ADP, and AMP hydrolysis and ADA activity (synaptosomes). Moreover, VIT D3 increased insulin levels and AMP hydrolysis (platelets) and improved antioxidant defense. Therefore, we suggest that VIT D3 treatment modulates hyperglycemia-induced changes via purinergic enzymes and receptor expression, consequently attenuating insulin homeostasis dysregulation in the diabetic state., Competing Interests: Declaration of competing interest The authors declare that there are no financial interests/personal relationships which may be considered as potential competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
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10. Association of vitamin D and cognition in people with type 2 diabetes: a systematic review.
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da Silva AD, Oliveira JS, de Castro IC, Paiva WC, Gomes JMG, and Pimenta LCJP
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- Adult, Aged, Humans, Cognition, Dietary Supplements, Vitamin D, Vitamins, Observational Studies as Topic, Randomized Controlled Trials as Topic, Young Adult, Middle Aged, Diabetes Mellitus, Type 2 complications, Vitamin D Deficiency complications, Vitamin D Deficiency epidemiology
- Abstract
Context: There is a high prevalence of vitamin D deficiency and impaired cognitive function in people with type 2 diabetes mellitus (T2DM)., Objective: To critically and systematically review the literature on the association between vitamin D status and cognitive performance in people with type 2 diabetes., Data Sources: This review was conducted according to PRISMA recommendations. MEDLINE, SCOPUS, the Cochrane Library, and Web of Science databases were searched using the terms "Diabetes Mellitus, Type 2", "Cognitive Function", and "Vitamin D"., Data Extraction: Eight observational and 1 randomized study were included, containing data of 14 648 adult and elderly individuals (19-74 y). All extracted data were compiled, compared, and critically analyzed., Data Analysis: There is no strong evidence that lower serum concentrations of vitamin D and vitamin D-binding protein are associated with worsening cognitive function in individuals with T2DM. Vitamin D supplementation (12 wk) improved the scores of some executive functioning tests, although there was no difference between low doses (5000 IU/wk) and high doses (50 000 IU/wk)., Conclusions: There is no high-quality evidence demonstrating an association between vitamin D status and cognitive function, or clinical benefits on cognition from vitamin D supplementation in individuals with T2DM. Future studies are needed. Systematic Review Registration: PROSPERO registration no. CRD42021261520., (© The Author(s) 2023. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2024
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11. The Transcriptome of BT-20 Breast Cancer Cells Exposed to Curcumin Analog NC2603 Reveals a Relationship between EGR3 Gene Modulation and Cell Migration Inhibition.
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Nishimura FG, Sampaio BB, do Couto GO, da Silva AD, da Silva WJ, Peronni KC, Evangelista AF, Hossain M, Dimmock JR, Bandy B, Beleboni RO, Marins M, and Fachin AL
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- Humans, Female, Cell Migration Inhibition, Transcriptome, Cell Line, Tumor, Cell Movement, Cell Proliferation, Apoptosis, Early Growth Response Protein 3 metabolism, Early Growth Response Protein 3 pharmacology, Curcumin, Breast Neoplasms drug therapy, Breast Neoplasms genetics, Breast Neoplasms metabolism, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use
- Abstract
Breast cancer represents a critical global health issue, accounting for a substantial portion of cancer-related deaths worldwide. Metastasis, the spread of cancer cells to distant organs, is the primary cause of approximately 90% of breast cancer-related fatalities. Despite advances in cancer treatment, conventional chemotherapeutic drugs often encounter resistance and demonstrate limited efficacy against metastasis. Natural products have emerged as promising sources for innovative cancer therapies, with curcumin being one such example. However, despite its therapeutic potential, curcumin exhibits several limitations. Analogous compounds possessing enhanced bioavailability, potency, or specificity offer a promising avenue for overcoming these challenges and demonstrate potent anti-tumor activities. Our study investigates the antimetastatic potential of the curcumin analog NC2603 in breast cancer cells, utilizing BT-20 cells known for their migratory properties. Cell viability assessments were performed using the MTT reduction method, while migration inhibition was evaluated through scratch and Transwell migration assays. Transcriptome analysis via next-generation sequencing was employed to elucidate gene modulation and compound mechanisms, with subsequent validation using RT-qPCR. The IC50 of NC2603 was determined to be 3.5 μM, indicating potent inhibition of cell viability, and it exhibited greater specificity for BT-20 cells compared with non-cancerous HaCaT cells, surpassing the efficacy of doxorubicin. Notably, NC2603 demonstrated superior inhibition of cell migration in both scratch and Transwell assays compared with curcumin. Transcriptome analysis identified 10,620 modulated genes. We validated the expression of six: EGR3, ATF3, EMP1, SOCS3, ZFP36, and GADD45B, due to their association with migration inhibition properties. We hypothesize that the curcumin analog induces EGR3 expression, which subsequently triggers the expression of ATF3, EMP1, SOCS3, ZFP36, and GADD45B. In summary, this study significantly advances our comprehension of the intricate molecular pathways involved in cancer metastasis, while also examining the mechanisms of analog NC2603 and underscoring its considerable potential as a promising candidate for adjuvant therapy.
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- 2024
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12. Resistance physical exercise alleviates lipopolysaccharide-triggered neuroinflammation in cortex and hippocampus of rats via purinergic signaling.
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Miron VV, Assmann CE, Mostardeiro VB, Bottari NB, Baldissarelli J, Reichert KP, da Silva AD, Castro MFV, de Jesus LB, da Silveira MV, Palma TV, Morsch VM, Cardoso AM, and Schetinger MRC
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- Rats, Animals, 5'-Nucleotidase metabolism, Neuroinflammatory Diseases, Hippocampus metabolism, Tumor Necrosis Factor-alpha metabolism, Interleukin-6 metabolism, Exercise, Caspases metabolism, Receptors, Purinergic P2X7 metabolism, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Lipopolysaccharides toxicity
- Abstract
Resistance physical exercise has neuroprotective and anti-inflammatory effects on many known diseases and, therefore, it has been increasingly explored. The way in which this type of exercise exerts these actions is still under investigation. In this study, we aimed to analyze the enzymes and components of the purinergic system involved in the inflammatory process triggered by the P2X7R. Rats were divided into four groups: control, exercise (EX), lipopolysaccharide (LPS), and EX + LPS. The animals in the exercise groups were subjected to a 12-week ladder-climbing resistance physical exercise and received LPS after the last session for sepsis induction. Enzymes activities (NTPDase, 5'-nucleotidase, and adenosine deaminase), purinoceptors' density (P2X7R, A1, and A2A), and the levels of inflammatory indicators (pyrin domain-containing protein 3 (NLRP3), Caspase-1, interleukin (IL)- 6, IL-1B, and tumor necrosis factor (TNF) -α) were measured in the cortex and hippocampus of the animals. The results show that exercise prevented (in the both structures) the increase of: 1) nucleoside-triphosphatase (NTPDase) and 5'-nucleotidase activities; 2) P2X7R density; 3) NLRP3 and Caspase-1; and 4) IL-6, IL-1β, and TNF-α It is suggested that the purinergic system and the inflammatory pathway of P2X7R are of fundamental importance and influence the effects of resistance physical exercise on LPS-induced inflammation. Thus, the modulation of the P2X7R by resistance physical exercise offers new avenues for the management of inflammatory-related illnesses., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
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13. Imidazo[1,2- a ]pyrimidine as a New Antileishmanial Pharmacophore against Leishmania amazonensis Promastigotes and Amastigotes.
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Kumar R, Singh R, das Chagas Almeida A, da Trindade Granato J, de Oliveira Lemos AS, Kumar K, Patil MT, da Silva AD, Rode AB, Coimbra ES, and Salunke DB
- Abstract
Leishmania poses a substantial threat to the human population all over the globe because of its visceral and cutaneous spread engendered by all 20 species. Unfortunately, the available drugs against leishmania are already hobbled with toxicity, prolonged treatment, and increasing instances of acquirement of resistance. Under these grave circumstances, the development of new drugs has become imperative to keep these harmful microbes at bay. To this end, a Groebke-Blackburn-Bienaymé multicomponent reaction-based library of different imidazo-fused heterocycles has been synthesized and screened against Leishmania amazonensis promastigotes and amastigotes. Among the library compounds, the imidazo-pyrimidine 24 has been found to be the most effective (inhibitory concentration of 50% (IC
50 ) < 10 μM), with selective antileishmanial activity on amastigote forms, a stage of the parasite related to human disease. The compound 24 has exhibited an IC50 value of 6.63 μM, being ∼two times more active than miltefosine, a reference drug. Furthermore, this compound is >10 times more destructive to the intracellular parasites than host cells. The observed in vitro antileishmanial activity along with suitable in silico physicochemical and absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of compound 24 reinforce the imidazo-pyrimidine scaffold as a new antileishmanial pharmacophore and encourage further murine experimental leishmaniasis studies., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)- Published
- 2023
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14. An indirect ELISA to detect antibodies to the gC of bovine alphaherpesvirus 1 (BoAHV1) displaying no crossreactivity with antibodies induced by bovine alphaherpesvirus 5 (BoAHV5).
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Esteves PA, Dellagostin OA, da Silva TC, Spilki FR, da Silva AD', Oliveira EAS, Franco AC, Hübner S, Chiminazzo C, Canal CW, Campos FS, and Roehe PM
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- Animals, Cattle, Seroepidemiologic Studies, Antibodies, Viral, Enzyme-Linked Immunosorbent Assay veterinary, Predictive Value of Tests, Sensitivity and Specificity, Herpesvirus 1, Bovine, Cattle Diseases diagnosis
- Abstract
Seroprevalence of bovine alphaherpesvirus type 1 (BoAHV1) infections may be contaminated by crossreactive antibodies to bovine alphaherpesvirus type 5 (BoAHV5). To avoid such crossreactivity, an indirect enzyme-linked immunosorbent assay prepared with a recombinant glycoprotein C (gC) antigen (ELISA-gC1) was developed, aiming the detection of antibodies to BoAHV1, with no crossreactivity with BoAHV5 antibodies. The antigen for the ELISA-gC1 was the product of the expression of 219 bp from the N-terminal portion of the BoAHV1 gC gene, which bears low homology between the two virus types. The test was validated on 131 bovine serum samples, including 26 sera from BoAHV1-experimentally immunized, 38 sera from BoAHV5-experimentally infected or immunized calves, and 67 sera from calves seronegative for both BoAHV1 and BoAHV5, as determined by serum neutralization (SN). When compared to SN for BoAHV1, the ELISA-gC1 presented 100% sensitivity, 95.5 % specificity, 100 % negative predictive value, 89.6 % positive predictive value, 98.8 % precision, and a kappa correlation coefficient (κ) 0.95. None of the 38 BoAHV5-seropositive calves was detected by the ELISA-gC1. The ELISA-gC1 proved highly effective for the identification of BoAHV1-positive sera, with no crossreactivity with anti-BoAHV5 antibodies, thus able to distinguish serological responses from BoAHV1- and BoAHV5-seropositive cattle. Its capacity to detect BoAHV1-specific antibodies should allow the determination of the actual BoAHV1 prevalence in herds, which cannot be serologically determined in countries where BoAHV5 is also prevalent due to antibody crossreactivity. Apart from recognizing exclusively BoAHV1-infected cattle, the ELISA-gC1 may also be used in support of BoAHV5 epidemiological studies by allowing the exclusion of BoAHV1-seropositive animals., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)
- Published
- 2023
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15. Electrochemically reduced graphene oxide films from Zn-C battery waste for the electrochemical determination of paracetamol and hydroquinone.
- Author
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Silva RM, Sperandio GH, da Silva AD, Okumura LL, da Silva RC, Moreira RPL, and Silva TA
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- Acetaminophen, Hydroquinones, Spectroscopy, Fourier Transform Infrared, Electrochemical Techniques methods, Carbon, Zinc, Graphite chemistry
- Abstract
Contributing to the development of sustainable electroanalytical chemistry, electrochemically reduced graphene oxide (ERGO) films obtained from residual graphite of discharged Zn-C batteries are proposed in this work. Graphite from the cathode of discarded Zn-C batteries was recovered and used in the synthesis of graphene oxide (GO) by the modified Hummer's method. The quality of the synthesized GO was verified using different characterization methods (FT-IR, XRD, SEM, and TEM). GO films were deposited on a glassy carbon electrode (GCE) by the drop coating method and then electrochemically reduced by cathodic potential scanning using cyclic voltammetry. The electrochemical features of the ERGO films were investigated using the ferricyanide redox probe, as well as paracetamol (PAR) and hydroquinone (HQ) molecules as model analytes. From the cyclic voltammetry assays, enhanced heterogeneous electron transfer rate constants (k
0 ) were observed for all redox systems studied. In analytical terms, the ERGO-based electrode showed higher analytical sensitivity than the bare and GO-modified GCE. Using differential pulse voltammetry, wide linear response ranges and limits of detection of 0.14 μmol L-1 and 0.65 μmol L-1 were achieved for PAR and HQ, respectively. Furthermore, the proposed sensor was successfully applied to the determination of PAR and HQ in synthetic urine and tap water samples (recoveries close to 100%). The outstanding electrochemical and analytical properties of the proposed ERGO films are added to the very low cost of the raw material, being presented as a green-based alternative for the development of electrochemical (bio)sensors with unsophisticated resources., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)- Published
- 2023
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16. In vitro high-content tissue models to address precision medicine challenges.
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Afewerki S, Stocco TD, Rosa da Silva AD, Aguiar Furtado AS, Fernandes de Sousa G, Ruiz-Esparza GU, Webster TJ, Marciano FR, Strømme M, Zhang YS, and Lobo AO
- Subjects
- Humans, COVID-19 Vaccines, SARS-CoV-2, Precision Medicine, COVID-19
- Abstract
The field of precision medicine allows for tailor-made treatments specific to a patient and thereby improve the efficiency and accuracy of disease prevention, diagnosis, and treatment and at the same time would reduce the cost, redundant treatment, and side effects of current treatments. Here, the combination of organ-on-a-chip and bioprinting into engineering high-content in vitro tissue models is envisioned to address some precision medicine challenges. This strategy could be employed to tackle the current coronavirus disease 2019 (COVID-19), which has made a significant impact and paradigm shift in our society. Nevertheless, despite that vaccines against COVID-19 have been successfully developed and vaccination programs are already being deployed worldwide, it will likely require some time before it is available to everyone. Furthermore, there are still some uncertainties and lack of a full understanding of the virus as demonstrated in the high number new mutations arising worldwide and reinfections of already vaccinated individuals. To this end, efficient diagnostic tools and treatments are still urgently needed. In this context, the convergence of bioprinting and organ-on-a-chip technologies, either used alone or in combination, could possibly function as a prominent tool in addressing the current pandemic. This could enable facile advances of important tools, diagnostics, and better physiologically representative in vitro models specific to individuals allowing for faster and more accurate screening of therapeutics evaluating their efficacy and toxicity. This review will cover such technological advances and highlight what is needed for the field to mature for tackling the various needs for current and future pandemics as well as their relevancy towards precision medicine., Competing Interests: Declaration of competing interest The authors declare no conflicts of interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2023
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17. Caffeic acid attenuates neuroinflammation and cognitive impairment in streptozotocin-induced diabetic rats: Pivotal role of the cholinergic and purinergic signaling pathways.
- Author
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Castro MFV, Assmann CE, Stefanello N, Reichert KP, Palma TV, da Silva AD, Miron VV, Mostardeiro VB, Morsch VMM, and Schetinger MRC
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- Rats, Animals, Rats, Wistar, Adenosine Deaminase metabolism, Acetylcholinesterase metabolism, Streptozocin, Neuroinflammatory Diseases, alpha7 Nicotinic Acetylcholine Receptor metabolism, Signal Transduction, Cholinergic Agents therapeutic use, Diabetes Mellitus, Experimental complications, Diabetes Mellitus, Experimental drug therapy, Cognitive Dysfunction drug therapy, Cognitive Dysfunction etiology
- Abstract
The present study evaluated the effect of caffeic acid (CA) on behavioral learning and memory tasks in the diabetic state. We also evaluated the effect of this phenolic acid on the enzymatic activities of acetylcholinesterase, ecto-nucleoside triphosphate diphosphohydrolase, ecto-5-nucleotidase and adenosine deaminase as well as on the density of M1R, α7nAChR, P2×7R, A1R, A2AR, and inflammatory parameters in the cortex and hippocampus of diabetic rats. Diabetes was induced by a single intraperitoneal dose of streptozotocin (55 mg/kg). The animals were divided into six groups: control/vehicle; control/CA 10 and 50 mg/kg; diabetic/vehicle; diabetic/CA 10 and 50 mg/kg, treated by gavage. The results showed that CA improved learning and memory deficits in diabetic rats. Also, CA reversed the increase in acetylcholinesterase and adenosine deaminase activities and reduced ATP and ADP hydrolysis. Moreover, CA increased the density of M1R, α7nAChR, and A1R receptors and reversed the increase in P2×7R and A2AR density in both evaluated structures. In addition, CA treatment attenuated the increase in NLRP3, caspase 1, and interleukin 1β density in the diabetic state; moreover, it increased the density of interleukin-10 in the diabetic/CA 10 mg/kg group. The results indicated that CA treatment positively modified the activities of cholinergic and purinergic enzymes and the density of receptors, and improved the inflammatory parameters of diabetic animals. Thus, the outcomes suggest that this phenolic acid could improve the cognitive deficit linked to cholinergic and purinergic signaling in the diabetic state., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2023
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18. Carbon Nanomaterials-Based Screen-Printed Electrodes for Sensing Applications.
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Silva RM, da Silva AD, Camargo JR, de Castro BS, Meireles LM, Silva PS, Janegitz BC, and Silva TA
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- Electrodes, Electrochemistry, Electrochemical Techniques, Nanotubes, Carbon, Biosensing Techniques
- Abstract
Electrochemical sensors consisting of screen-printed electrodes (SPEs) are recurrent devices in the recent literature for applications in different fields of interest and contribute to the expanding electroanalytical chemistry field. This is due to inherent characteristics that can be better (or only) achieved with the use of SPEs, including miniaturization, cost reduction, lower sample consumption, compatibility with portable equipment, and disposability. SPEs are also quite versatile; they can be manufactured using different formulations of conductive inks and substrates, and are of varied designs. Naturally, the analytical performance of SPEs is directly affected by the quality of the material used for printing and modifying the electrodes. In this sense, the most varied carbon nanomaterials have been explored for the preparation and modification of SPEs, providing devices with an enhanced electrochemical response and greater sensitivity, in addition to functionalized surfaces that can immobilize biological agents for the manufacture of biosensors. Considering the relevance and timeliness of the topic, this review aimed to provide an overview of the current scenario of the use of carbonaceous nanomaterials in the context of making electrochemical SPE sensors, from which different approaches will be presented, exploring materials traditionally investigated in electrochemistry, such as graphene, carbon nanotubes, carbon black, and those more recently investigated for this (carbon quantum dots, graphitic carbon nitride, and biochar). Perspectives on the use and expansion of these devices are also considered.
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- 2023
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19. Exploring the repositioning of the amodiaquine as potential drug against visceral leishmaniasis: The in vitro effect against Leishmania infantum is associated with multiple mechanisms, involving mitochondria dysfunction, oxidative stress and loss of cell cycle control.
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Antinarelli LMR, Midlej V, da Silva EDS, Coelho EAF, da Silva AD, and Coimbra ES
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- Animals, Mice, Amodiaquine pharmacology, Amodiaquine metabolism, Amodiaquine therapeutic use, Reactive Oxygen Species metabolism, Drug Repositioning, Oxidative Stress, Mitochondria metabolism, Cell Cycle Checkpoints, Mice, Inbred BALB C, Leishmaniasis, Visceral drug therapy, Leishmaniasis, Visceral metabolism, Leishmania infantum, Antiprotozoal Agents pharmacology, Antiprotozoal Agents therapeutic use
- Abstract
Visceral leishmaniasis (VL) is a progressive, debilitating, and potentially fatal disease if left untreated. As a neglected tropical disease (NTD), the available treatment is restricted to a few drugs, which typically must be administered over a long period but are associated with serious adverse effects and have variability in efficacy. In this sense, drug repositioning has been considered an excellent strategy in the search for alternative treatments, especially in reducing the time and cost of the research. In this work, the repositioning potential of amodiaquine (AQ), a well-known antimalarial drug, was investigated for the treatment of VL. AQ showed significant and selective activity against promastigotes (IC
50 = 11.6 μg/mL) and intracellular amastigotes (IC50 = 2.4 μg/mL) of L. infantum, being 10 times more destructive to the intracellular parasites than the host cell. In addition, pre-treatment of macrophages with AQ caused a significant reduction in the infection index, indicating a prophylactic effect of this drug. SEM images showed that AQ induces strong shape alterations of the promastigotes with an increase in cell volume with rounding and ribbing (vertical ridges), as well as a shortened flagellum. In addition, AQ induced depolarization of the ΔΨm, an increase in ROS and neutral lipids levels, and changes in the cell cycle in promastigotes, without alterations to the permeability of the parasite plasma membrane. L. infantum-infected macrophages treated with AQ induced the activation of oxidative mechanisms by infected host cells, with an increase in ROS and NO levels. Finally, in vitro interactions between AQ and miltefosine were found to have an additive effect in both biological stages of the parasite, with the ∑FIC50 values ranging from 0.74 to 1.16 μg/mL and 0.54-1.11 μg/mL for promastigotes and intracellular amastigotes, respectively. Overall, these data highlight the utility of drug repurposing and indicate future preclinical testing for AQ itself or in combination as a potential VL treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2023
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20. Concise two-step chemical synthesis of molnupiravir.
- Author
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Pereira VRD, Bezerra MAM, Gomez MRBP, Martins GM, da Silva AD, de Oliveira KT, de Souza ROMA, and Amarante GW
- Abstract
A concise synthesis of molnupiravir in a one-pot two-step approach starting from uridine is described. Formally, herein, two sets of one-pot two-reaction steps introducing simplicity for purifications and using chemically available reagents are presented. In this context, molnupiravir was obtained in up to 68% overall yield and multigram-scale. In addition, HPLC analysis showed the molnupiravir purity above 99%., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2022
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21. Acute toxicity and antitumor potential of 1,3,4-trisubstituted-1,2,3-triazole dhmtAc-loaded liposomes on a triple-negative breast cancer model.
- Author
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Ramos JP, Abdel-Salam MAL, Nobre DAB, Glanzmann N, de Souza CP, Leite EA, de Abreu Teles PP, Barbosa AS, Barcelos LS, Dos Reis DC, Cassali GD, de Lima ME, de Castro QJT, Grabe-Guimarães A, da Silva AD, and de Souza-Fagundes EM
- Subjects
- Animals, Cell Line, Tumor, Humans, Leukocytes, Mononuclear, Mice, Mice, Inbred BALB C, Structure-Activity Relationship, Triazoles pharmacology, Liposomes, Triple Negative Breast Neoplasms drug therapy
- Abstract
For the first time, compounds developed from the 1,2,3-triazole scaffold were evaluated as novel drugs to treat triple-negative breast cancer (TNBC). Four organic salts were idealized as nonclassical bioisosteres of miltefosine, which is used in the topical treatment for skin metastasizing breast carcinoma. Among them, derivative dhmtAc displayed better solubility and higher cytotoxicity against the human breast adenocarcinoma cell line and mouse 4T1 cell lines, which are representatives of TNBC. In vitro assays revealed that dhmtAc interferes with cell integrity, confirmed by lactate dehydogenase leakage. Due to its human peripheral blood mononuclear cell (PBMC) toxicity, dhmtAc in vivo studies were carried out with the drug incorporated in a long-circulating and pH-sensitive liposome (SpHL-dhmtAc), and the acute toxicity in BALB/c mice was determined. Free dhmtAc displayed cardiac and pulmonary toxicity after the systemic administration of 5 mg/kg doses. On the other hand, SpHL-dhmtAc displayed no toxicity at 20 mg/kg. The in vivo antitumor effect of SpHL-dhmtAc was investigated using the 4T1 heterotopic murine model. Intravenous administration of SpHL-dhmtAc reduced the tumor volume and weight, without interfering with the body weight, compared with the control group and the dhmtAc free form. The incorporation of the triazole compound in the liposome allowed the demonstration of its anticancer potential. These findings evidenced 1,3,4-trisubstituted-1,2,3-triazole as a promising scaffold for the development of novel drugs with applicability for the treatment of patients with TNBC., (© 2022 Deutsche Pharmazeutische Gesellschaft.)
- Published
- 2022
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22. Parasitological and immunological evaluation of a quinoline derivative salt incorporated into a polymeric micelle formulation against Leishmania infantum infection.
- Author
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Ribeiro Antinarelli LM, Glanzmann N, Mendonça DVC, Lage DP, Oliveira-da-Silva JA, Tavares GSV, Carvalho AMRS, Freitas CS, Martins VT, Duarte MC, Menezes-Souza D, da Silva AD, Coelho EAF, and Soares Coimbra E
- Subjects
- Animals, Mice, Mice, Inbred BALB C, Micelles, Nitrites therapeutic use, Polymers therapeutic use, Antiprotozoal Agents therapeutic use, Leishmania infantum, Leishmaniasis parasitology, Leishmaniasis, Visceral drug therapy, Leishmaniasis, Visceral parasitology, Quinolines therapeutic use
- Abstract
Leishmaniasis is a parasitic disease caused by Leishmania protozoa, which presents a large spectrum of clinical manifestations. In the present study, a quinoline derivative salt named N-(2-((7-chloroquinolin-4-yl)amino)ethyl)-N-(prop-2-yn-1-yl)prop-2-yn-1-aminium chloride or QDS3 was in vitro and in vivo tested against L. infantum by means of its incorporation in Poloxamer 407-based polymeric micelles (QDS3/M). The in vitro antileishmanial activity of QDS3 and QDS3/M was investigated in L. infantum promastigotes, axenic amastigotes and infected macrophages. BALB/c mice were infected with L. infantum, and parasitological parameters were evaluated 1 and 15 days post-treatment by determining the parasite load by a limiting dilution assay, besides a quantitative PCR (qPCR) method. Immunological response was assessed based on production of cellular cytokines, as well as by quantification of nitrite levels and specific antibodies. In vitro results showed that QDS3 free or in micelles presented effective antileishmanial action against both parasite stages, being more effective in amastigotes. In vivo data showed that treatment using QDS3 or QDS3/M reduced the parasite load in the livers, spleens, draining lymph nodes (dLN) and bone marrows of the treated animals, 1 and 15 days after treatment, when compared to values found in the control groups. Additionally, treated mice developed a polarized Th1-type immune response, with higher levels of IL-12, IFN-γ, GM-CSF and nitrite, besides high production of specific IgG2a antibodies, when compared to the controls. Parasitological and immunological data obtained using the micellar composition were better than the others. In conclusion, QDS3, mainly when applied in a delivery adjuvant system, could be considered for future studies as therapeutic candidate against VL., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2022
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23. Functionalized 1,2,3-triazolium salts as potential agents against visceral leishmaniasis.
- Author
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das Chagas Almeida A, Meinel RS, Leal YL, Silva TP, Glanzmann N, Mendonça DVC, Perin L, Cunha-Júnior EF, Coelho EAF, Melo RCN, da Silva AD, and Coimbra ES
- Subjects
- Animals, Dogs, Mice, Mice, Inbred BALB C, Salts pharmacology, Salts therapeutic use, Triazoles pharmacology, Triazoles therapeutic use, Antiprotozoal Agents therapeutic use, Leishmania infantum, Leishmaniasis, Visceral drug therapy, Leishmaniasis, Visceral parasitology
- Abstract
Visceral leishmaniasis (VL) is the most severe clinical form of leishmaniasis, being fatal if untreated. In search of a more effective treatment for VL, one of the main strategies is the development and screening of new antileishmanial compounds. Here, we reported the synthesis of seven new acetyl functionalized 1,2,3-triazolium salts, together with four 1,2,3-triazole precursors, and investigated their effect against different strains of L. infantum from dogs and humans. The 1,2,3-triazolium salts exhibited better activity than the 1,2,3-triazole derivatives with IC
50 range from 0.12 to 8.66 μM and, among them, compound 5 showed significant activity against promastigotes (IC50 from 4.55 to 5.28 μM) and intracellular amastigotes (IC50 from 5.36 to 7.92 μM), with the best selective index (SI ~ 6-9) and reduced toxicity. Our findings, using biochemical and ultrastructural approaches, demonstrated that compound 5 targets the mitochondrion of L. infantum promastigotes, leading to the formation of reactive oxygen species (ROS), increase of the mitochondrial membrane potential, and mitochondrial alteration. Moreover, quantitative transmission electron microscopy (TEM) revealed that compound 5 induces the reduction of promastigote size and cytoplasmic vacuolization. Interestingly, the effect of compound 5 was not associated with apoptosis or necrosis of the parasites but, instead, seems to be mediated through a pathway involving autophagy, with a clear detection of autophagic vacuoles in the cytoplasm by using both a fluorescent marker and TEM. As for the in vivo studies, compound 5 showed activity in a mouse model of VL at 20 mg/kg, reducing the parasite load in both spleen and liver (59.80% and 26.88%, respectively). Finally, this compound did not induce hepatoxicity or nephrotoxicity and was able to normalize the altered biochemical parameters in the infected mice. Thus, our findings support the use of 1,2,3-triazolium salts as potential agents against visceral leishmaniasis., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2022
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24. The kinetics of formation of resveratrol-β-cyclodextrin-NH 2 and resveratrol analog-β-cyclodextrin-NH 2 supramolecular complexes.
- Author
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Acipreste Hudson E, Campos de Paula HM, Coelho YL, Glanzmann N, da Silva AD, Mendes da Silva LH, and Dos Santos Pires AC
- Subjects
- Kinetics, Polyphenols, Resveratrol, Surface Plasmon Resonance, Cyclodextrins
- Abstract
The determination of the kinetics of inclusion processes is significant for the application of inclusion complexes as carriers for bioactive molecules. We determined the kinetic parameters of inclusion between modified β-cyclodextrin (β-CD-NH
2 ) and the polyphenols resveratrol (RES) and its structural analog (RESAn1), using the real-time analysis of surface plasmon resonance. The association and dissociation rate constants (ka and kd ) showed that RESAn1 inclusion and its dissociation from β-CD-NH2 were faster than a similar process for RES ( [Formula: see text] = 3.10∙104 ± 0.14 M-1 s-1 , [Formula: see text] =1.87∙103 ± 0.11 M-1 s-1 ; [Formula: see text] =0.39 ± 0.02 s-1 , [Formula: see text] =0.30 ± 0.02 s-1 , at 25 °C). The activated complex formation was also affected by the structural differences between the polyphenols, as showed by the activation energies of the association step ( [Formula: see text] 14.81 ± 0.64 kJ∙mol-1 , [Formula: see text] -15.01 ± 0.75 to 82.35 ± 4.47 kJ∙mol-1 ). These effects of polyphenol structural differences are due to the desolvation process of interacting molecules. These results elucidate the role of small group to the dynamics of the molecular inclusion of β-CD., (Copyright © 2021 Elsevier Ltd. All rights reserved.)- Published
- 2022
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25. Involvement of ectonucleotidases and purinergic receptor expression during acute Chagas disease in the cortex of mice treated with resveratrol and benznidazole.
- Author
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Fracasso M, Reichert K, Bottari NB, da Silva AD, Schetinger MRC, Monteiro SG, and da Silva AS
- Subjects
- Acute Disease, Animals, Antioxidants administration & dosage, Cerebral Cortex parasitology, Chagas Disease drug therapy, Female, Gene Expression, Immunosuppressive Agents administration & dosage, Mice, Oxidative Stress drug effects, Oxidative Stress physiology, Receptors, Purinergic genetics, Cerebral Cortex drug effects, Cerebral Cortex metabolism, Chagas Disease metabolism, Nitroimidazoles administration & dosage, Receptors, Purinergic biosynthesis, Resveratrol administration & dosage
- Abstract
Chagas disease (CD) is caused by the parasite Trypanosoma cruzi. CD affects people worldwide, primarily in tropical areas. The central nervous system (CNS) is an essential site for T. cruzi persistence during infection. The protozoan may pass through the blood-brain barrier and may cause motor and cognitive neuronal damage. Once in the CNS, T. cruzi triggers immune responses that the purinergic system can regulate. Treatment for CD is based on benznidazole (BNZ); however, this agent has negative side-effects and is toxic to the host. For this reason, we investigated whether resveratrol (RSV), a potent antioxidant and neuroprotective molecule, would modulate purinergic signaling and RSV alone or in combination with BNZ would prevent changes in purinergic signaling and oxidative damage caused by T. cruzi. We infected mice with T. cruzi and treated them with RSV or BNZ for 8 days. Increases in ATP and ADP hydrolysis by NTPDase in the total cortex of infected animals were observed. The treatment with RSV in infected group diminished ATP, ADP, and AMP hydrolysis compared to infected group. The combination of RSV + BNZ decreased AMP hydrolysis in infected animals compared to the INF group, exerting an anti-inflammatory effect. RSV acted as a neuroprotector, decreasing adenosine levels. Infected animals presented an increase of P2X
7 and A2A density of purine receptors. RSV reduced P2X7 and A2A and increased A1 density receptors in infected animals. In addition, infected animals showed higher TBARS and reactive oxygen species (ROS) levels than control. RSV diminished ROS levels in infected mice, possibly due to antioxidant properties. In short, we conclude that resveratrol could act as a neuroprotective molecule, probably preventing inflammatory changes caused by infection by T. cruzi, even though the mice experienced high levels of parasitemia., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)- Published
- 2021
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26. Synthesis and biological activity of novel 4-aminoquinoline/1,2,3-triazole hybrids against Leishmania amazonensis.
- Author
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Glanzmann N, Antinarelli LMR, da Costa Nunes IK, Pereira HMG, Coelho EAF, Coimbra ES, and da Silva AD
- Subjects
- Aminoquinolines chemical synthesis, Animals, Antiprotozoal Agents chemistry, Apoptosis drug effects, Cell Cycle drug effects, Cell Membrane chemistry, Cell Membrane metabolism, DNA Fragmentation drug effects, Female, Lipid Metabolism drug effects, Macrophages parasitology, Membrane Potential, Mitochondrial drug effects, Mice, Mice, Inbred BALB C, Organelles drug effects, Phosphatidylserines pharmacology, Reactive Oxygen Species metabolism, Triazoles chemical synthesis, Aminoquinolines pharmacology, Antiprotozoal Agents pharmacology, Leishmania mexicana drug effects, Triazoles pharmacology
- Abstract
Quinoline and 1,2,3-triazoles are well-known nitrogen-based heterocycles presenting diverse pharmacological properties, although their antileishmanial activity is still poorly exploited. As an effort to contribute with studies involving these interesting chemical groups, in the present study, a series of compounds derived from 4-aminoquinoline and 1,2,3-triazole were synthetized and biological studies using L. amazonensis species were performed. The results pointed that the derivative 4, a hybrid of 4-aminoquinoline/1,2,3-triazole exhibited the best antileishmanial action, with inhibitory concentration (IC
50 ) values of ~1 µM against intramacrophage amastigotes of L. amazonensis , and being 16-fold more active to parasites than to the host cell. The mechanism of action of derivative 4 suggest a multi-target action on Leishmania parasites, since the treatment of L. amazonensis promastigotes caused mitochondrial membrane depolarization, accumulation of ROS products, plasma membrane permeabilization, increase in neutral lipids, exposure of phosphatidylserine to the cell surface, changes in the cell cycle and DNA fragmentation. The results suggest that the antileishmanial effect of this compound is primarily altering critical biochemical processes for the correct functioning of organelles and macromolecules of parasites, with consequent cell death by processes related to apoptosis-like and necrosis. No up-regulation of reactive oxygen and nitrogen intermediates was promoted by derivative 4 on L. amazonensis -infected macrophages, suggesting a mechanism of action independent from the activation of the host cell. In conclusion, data suggest that derivative 4 presents selective antileishmanial effect, which is associated with multi-target action, and can be considered for future studies for the treatment against disease., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)- Published
- 2021
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27. Toll-like receptor-7/8 agonist kill Leishmania amazonensis by acting as pro-oxidant and pro-inflammatory agent.
- Author
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Kaushik D, Granato JT, Macedo GC, Dib PRB, Piplani S, Fung J, da Silva AD, Coimbra ES, Petrovsky N, and Salunke DB
- Subjects
- Animals, Antiprotozoal Agents chemical synthesis, Cytokines metabolism, Female, Humans, Imidazoles, Imiquimod, Inflammation metabolism, Leishmaniasis parasitology, Macrophages, Peritoneal parasitology, Mice, Inbred BALB C, Nitric Oxide metabolism, Reactive Oxygen Species metabolism, Mice, Antiprotozoal Agents pharmacology, Leishmania drug effects, Macrophages, Peritoneal drug effects, Toll-Like Receptor 7 agonists, Toll-Like Receptor 8 agonists
- Abstract
Objectives: Evaluation of the anti-Leishmanial activity of imidazoquinoline-based TLR7/8 agonists., Methods: TLR7/8-active imidazoquinolines (2 and 3) were synthesized and assessed for activity against Leishmania amazonensis-intracellular amastigotes using mouse peritoneal macrophages. The production of reactive oxygen species (ROS), nitric oxide (NO) and cytokines was determined in infected and non-infected macrophages., Key Findings: The imidazoquinolines, 2 and 3, were primarily agonists of TLR7 with compound 3 also showing modest TLR8 activity. Docking studies showed them to occupy the same binding pocket on TLR7 and 8 as the known agonists, imiquimod and resiquimod. Compounds 2 and 3 inhibited the growth of L. amazonensis-intracellular amastigotes with the most potent compound (3, IC50 = 5.93 µM) having an IC50 value close to miltefosine (IC50 = 4.05 µM), a known anti-Leishmanial drug. Compound 3 induced macrophages to produce ROS, NO and inflammatory cytokines that likely explain the anti-Leishmanial effects., Conclusions: This study shows that activating TLR7 using compounds 2 or 3 induces anti-Leishmanial activity associated with induction of free radicals and inflammatory cytokines able to kill the parasites. While 2 and 3 had a very narrow cytotoxicity window for macrophages, this identifies the possibility to further develop this chemical scaffold to less cytotoxic TLR7/8 agonist for potential use as anti-Leishmanial drug., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2021
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28. Modulatory effects of caffeic acid on purinergic and cholinergic systems and oxi-inflammatory parameters of streptozotocin-induced diabetic rats.
- Author
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Castro MFV, Stefanello N, Assmann CE, Baldissarelli J, Bagatini MD, da Silva AD, da Costa P, Borba L, da Cruz IBM, Morsch VM, and Schetinger MRC
- Subjects
- Acetylcholinesterase genetics, Adenosine Deaminase genetics, Adenosine Deaminase metabolism, Animals, Antigens, CD genetics, Antigens, CD metabolism, Antioxidants pharmacology, Apyrase genetics, Apyrase metabolism, Butyrylcholinesterase genetics, Cytokines metabolism, Diabetes Mellitus, Experimental drug therapy, Diabetes Mellitus, Experimental metabolism, Diabetes Mellitus, Type 1 drug therapy, Diabetes Mellitus, Type 1 metabolism, Diabetes Mellitus, Type 1 pathology, GPI-Linked Proteins genetics, GPI-Linked Proteins metabolism, Lipid Peroxidation drug effects, Lymphocytes drug effects, Lymphocytes metabolism, Lymphocytes pathology, Male, Membrane Proteins genetics, Membrane Proteins metabolism, Peroxidase metabolism, Rats, Rats, Wistar, alpha7 Nicotinic Acetylcholine Receptor genetics, alpha7 Nicotinic Acetylcholine Receptor metabolism, Acetylcholinesterase metabolism, Butyrylcholinesterase metabolism, Caffeic Acids pharmacology, Diabetes Mellitus, Experimental pathology, Gene Expression Regulation drug effects, Inflammation Mediators metabolism, Oxidative Stress drug effects
- Abstract
Diabetes mellitus (DM) is a metabolic disorder characterized by a chronic hyperglycemia state, increased oxidative stress parameters, and inflammatory processes., Aims: To evaluate the effect of caffeic acid (CA) on ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) and adenosine deaminase (ADA) enzymatic activity and expression of the A2A receptor of the purinergic system, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymatic activity and expression of the α7nAChR receptor of the cholinergic system as well as inflammatory and oxidative parameters in diabetic rats., Methods: Diabetes was induced by a single dose intraperitoneally of streptozotocin (STZ, 55 mg/kg). Animals were divided into six groups (n = 10): control/oil; control/CA 10 mg/kg; control/CA 50 mg/kg; diabetic/oil; diabetic/CA 10 mg/kg; and diabetic/CA 50 mg/kg treated for thirty days by gavage., Results: CA treatment reduced ATP and ADP hydrolysis (lymphocytes) and ATP levels (serum), and reversed the increase in ADA and AChE (lymphocytes), BuChE (serum), and myeloperoxidase (MPO, plasma) activities in diabetic rats. CA treatment did not attenuate the increase in IL-1β and IL-6 gene expression (lymphocytes) in the diabetic state; however, it increased IL-10 and A2A gene expression, regardless of the animals' condition (healthy or diabetic), and α7nAChR gene expression. Additionally, CA attenuated the increase in oxidative stress markers and reversed the decrease in antioxidant parameters of diabetic animals., Conclusion: Overall, our findings indicated that CA treatment positively modulated purinergic and cholinergic enzyme activities and receptor expression, and improved oxi-inflammatory parameters, thus suggesting that this phenolic acid could improve redox homeostasis dysregulation and purinergic and cholinergic signaling in the diabetic state., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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29. Genetic and chemical control of coffee rust (Hemileia vastatrix Berk et Br.): impacts on coffee (Coffea arabica L.) quality.
- Author
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Pereira DR, Nadaleti DH, Rodrigues EC, da Silva AD, Malta MR, de Carvalho SP, and Carvalho GR
- Subjects
- Basidiomycota genetics, Coffea chemistry, Coffee chemistry, Genotype, Humans, Seeds microbiology, Taste, Basidiomycota physiology, Coffea microbiology, Plant Diseases microbiology, Seeds chemistry
- Abstract
Background: The occurrence of diseases can alter coffee (Coffea arabica L.) metabolism, causing changes in the composition of coffee beans and beverage quality. However, little is known about which aspects of coffee quality are actually altered by rust (Hemileia vastatrix Berk et Br.) and by its main control methods. The effect of chemical and genetic methods for the control of coffee rust on the quality of coffee beans and beverage was investigated., Results: Both genetic and chemical control reduce the damage caused by the disease in the composition of coffee beans. Genotypes with resistant ancestry, even with resistance breakdown, respond better to chemical control. The combination of genetic and chemical control favors an increase in the sugar content in the beans., Conclusions: Despite the fact that both genetic and chemical control are effective in reducing disease damage regarding the chemical composition of beans, the quality potential of Timor Hybrid genotypes associated with the cancellation of rust expression through the joint action of genetic and chemical control favors the composition of beans and, consequently, the quantitative assessment of sensory attributes, adding value to the final product. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)
- Published
- 2021
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30. Effects of curcumin and yucca extract addition in feed of broilers on microorganism control (anticoccidial and antibacterial), health, performance and meat quality.
- Author
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Galli GM, Griss LG, Boiago MM, Petrolli TG, Glombowsky P, Bissacotti BF, Copetti PM, da Silva AD, Schetinger MR, Sareta L, Mendes RE, Mesadri J, Wagner R, Gundel S, Ourique AF, and Da Silva AS
- Subjects
- Animal Feed analysis, Animals, Anti-Bacterial Agents administration & dosage, Chickens growth & development, Coccidiostats administration & dosage, Diet veterinary, Dietary Supplements analysis, Male, Meat analysis, Plant Extracts administration & dosage, Random Allocation, Anti-Bacterial Agents metabolism, Chickens metabolism, Coccidiostats metabolism, Curcumin chemistry, Plant Extracts metabolism, Yucca chemistry
- Abstract
The aim of this study was to determine whether curcumin and yucca extract addition in broiler feed improves growth, health, and meat quality, and to measure coccidiostatic and antimicrobial activity so as to enable replacement of conventional performance enhancers. We used 240 birds in four treatments: CN, basal feed with antibiotics and coccidiostatic drugs; CU, feed with 100 mg/kg of curcumin; YE, feed with 250 mg/kg of yucca extract; and CU + YE, feed with the combination of 100 mg curcumin/kg and 250 mg yucca extract/kg. A significant reduction in oocysts was observed in birds supplemented with combined additives (CU + YE) at days 37 compared to other treatments and at 42 days in relation to the CU treatment. At 42 days, the total bacterial counts for the CN and CU treatments were lower than the others. Birds fed the additive had lower numbers of leukocytes, lymphocytes, and heterophils than did those in the CN treatment. The highest levels of antioxidants in meat were observed in the treatments with the additives, together with lower levels of lipid peroxidation compared to the CN. The lowest protein oxidation was observed in the CU + YE treatment in relation to the other treatments. Lower total levels of saturated fatty acids (SFA) were observed in the CU treatment than in the CN. There were lower levels of monounsaturated fatty acids (MUFA) in the meat of birds in the YE treatment in relation to the others. Higher levels of total polyunsaturated fatty acids (PUFA) were observed in birds that consumed curcumin, individually and in combination with yucca extract. Taken together, the data suggest that curcumin and yucca extract are additives that can potentially replace conventional growth promoters; they improved bird health. Changes in the fatty acid profile of meat (increase in the percentage of omegas) are beneficial to the health of the consumer., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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31. In silico, in vitro and in vivo studies indicate resveratrol analogue as a potential alternative for neuroinflammatory disorders.
- Author
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de Assis PM, Fávero A, Menegasso JF, Meinel RS, Marion GM, Nunes VSP, Goliatt PVZC, da Silva AD, Dutra RC, and Raposo NRB
- Subjects
- Animals, Computer Simulation, In Vitro Techniques, Inflammation chemically induced, Lipopolysaccharides toxicity, Male, Mice, Molecular Docking Simulation, Nervous System Diseases chemically induced, Resveratrol analogs & derivatives, Scopolamine administration & dosage, Anti-Inflammatory Agents therapeutic use, Inflammation drug therapy, Nervous System Diseases drug therapy, Neuroprotective Agents therapeutic use, Resveratrol therapeutic use
- Abstract
Inflammaging is known as an imbalance between pro-inflammatory and anti-inflammatory immune mechanisms, being related to the onset of neurological disorders, such as major depression and Alzheimer's disease. Considering the known disadvantages regarding the FDA approved drug to manage such illnesses, resveratrol emerges as a natural drug candidate, despite its low bioavailability. In this study, resveratrol analogues were evaluated for their capacity of inhibiting acetylcholinesterase in silico, in vitro, and in vivo. Molecular docking simulations pointed out RSVA1 and RSVA6 as potent inhibitors, even more than resveratrol. Ellman's assay demonstrated RSVA6 as capable of inhibiting 92.4% of the enzyme activity. Further, male Swiss mice were pretreated with RSVA6 (100 mg kg
-1 ) 60 min before receiving scopolamine (1 mg kg-1 ). The Novel Recognition Object (NOR), Object Location (OLT), and Buried Pellet tests (BPL) demonstrated an RSVA6 neuroprotective effect. In the second round of tests, mice received a single intraperitoneal injection of lipopolysaccharide (0.5 mg kg-1 ) 24 h before treatment with RSVA6 (1, 10, and 100 mg kg-1 ). The Open Field (OFT), Tail Suspension (TST), and Splash tests (ST) were evaluated. LPS had no significant effect on the crossing and rearing number, indicating an association between the immobility time and anhedonia observed in the TST and ST, respectively, with depressive-like behavior. RSVA6 significantly reduced the depressive-like behavior triggered by LPS in the TST and ST. Altogether, our data suggest RSVA6 as a potential drug candidate for the treatment of neuroinflammatory conditions., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest regarding the publication of this article., (Copyright © 2020 Elsevier Inc. All rights reserved.)- Published
- 2020
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32. Human serum albumin-resveratrol complex formation: Effect of the phenolic chemical structure on the kinetic and thermodynamic parameters of the interactions.
- Author
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Rezende JP, Hudson EA, De Paula HMC, Meinel RS, Da Silva AD, Da Silva LHM, and Pires ACDS
- Subjects
- Humans, Hydrogen-Ion Concentration, Immobilized Proteins chemistry, Immobilized Proteins metabolism, Kinetics, Protein Binding, Resveratrol chemistry, Serum Albumin, Human chemistry, Surface Plasmon Resonance, Temperature, Thermodynamics, Phenols chemistry, Resveratrol metabolism, Serum Albumin, Human metabolism
- Abstract
The thermodynamics and kinetics of binding between human serum albumin (HSA) and resveratrol (RES) or its analog (RESAn1) were investigated by surface plasmon resonance (SPR). The binding constant and the kinetic constants of association and dissociation indicated that RESAn1 has higher affinity toward HSA than does RES. The formation of these complexes was entropically driven ( [Formula: see text] , [Formula: see text] KJ mol
-1 ). However, for both polyphenols, the activation energy (Eact ) of association (a) of free molecules was higher than that for dissociation (d) of the stable complex ( [Formula: see text] KJ mol-1 ), and the rate of association was faster than that of dissociation since the activation Gibbs free energy (ΔG‡ ) was lower for the former (ΔGaHSA-RES ‡ ≅54.73,ΔGdHSA-RES ‡ ≅73.83,ΔGaHSA-RESAn1 ‡ ≅54.14,ΔGdHSA-RESAn1 ‡ ≅73.97 KJ mol-1 ). This study showed that small differences in the structure of polyphenols such as RES and RESAn1 influenced the thermodynamics and kinetics of the complex formation with HSA., (Copyright © 2019 Elsevier Ltd. All rights reserved.)- Published
- 2020
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33. Taba: A Tool to Analyze the Binding Affinity.
- Author
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da Silva AD, Bitencourt-Ferreira G, and de Azevedo WF Jr
- Subjects
- Ligands, Machine Learning, Models, Molecular, Thermodynamics, Proteins chemistry, Software
- Abstract
Evaluation of ligand-binding affinity using the atomic coordinates of a protein-ligand complex is a challenge from the computational point of view. The availability of crystallographic structures of complexes with binding affinity data opens the possibility to create machine-learning models targeted to a specific protein system. Here, we describe a new methodology that combines a mass-spring system approach with supervised machine-learning techniques to predict the binding affinity of protein-ligand complexes. The combination of these techniques allows exploring the scoring function space, generating a model targeted to a protein system of interest. The new model shows superior predictive performance when compared with classical scoring functions implemented in the programs Molegro Virtual Docker, AutoDock4, and AutoDock Vina. We implemented this methodology in a new program named Taba. Taba is implemented in Python and available to download under the GNU license at https://github.com/azevedolab/taba. © 2019 Wiley Periodicals, Inc., (© 2019 Wiley Periodicals, Inc.)
- Published
- 2020
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34. Novel functionalized 1,2,3-triazole derivatives exhibit antileishmanial activity, increase in total and mitochondrial-ROS and depolarization of mitochondrial membrane potential of Leishmania amazonensis.
- Author
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Meinel RS, Almeida ADC, Stroppa PHF, Glanzmann N, Coimbra ES, and da Silva AD
- Subjects
- Animals, Leishmania mexicana metabolism, Leishmaniasis, Cutaneous drug therapy, Leishmaniasis, Cutaneous parasitology, Macrophages, Peritoneal drug effects, Macrophages, Peritoneal metabolism, Mice, Mice, Inbred BALB C, Mitochondria metabolism, Phosphorylcholine analogs & derivatives, Phosphorylcholine pharmacology, Antiprotozoal Agents pharmacology, Leishmania mexicana drug effects, Membrane Potential, Mitochondrial drug effects, Mitochondria drug effects, Reactive Oxygen Species metabolism, Triazoles pharmacology
- Abstract
1,2,3-triazolium salts are poorly understood regarding their antileishmanial activity. Hence, as an effort to identify novel chemical scaffolds as antileishmanial agents, a series of 1,2,3-triazolium salts (TS) and corresponding 1,2,3-triazole (T) precursors including new epoxide derivatives were synthesized and assayed against Leishmania amazonensis promastigote and intracellular amastigote forms. Among them, the compound TS-6 exhibited promising activity on promastigotes (IC
50 = 3.61 μM) and intracellular amastigotes (IC50 = 7.61 μM) of L. amazonensis, superior to miltefosine (IC50 > 10.0 μM), used as reference drug. In addition, TS-6 showed negligible cytotoxicity on murine peritoneal macrophages with a SI of about 10. Studies on the mode of action of TS-6 indicate mitochondrial dysfunction through an increase in 'total' and mitochondrial-ROS as well as depolarization of mitochondrial membrane potential of L. amazonensis promastigotes. In silico physicochemical studies indicate that the TS-6 could potentially be used as an oral drug., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2020
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35. Resveratrol analogues present effective antileishmanial activity against promastigotes and amastigotes from distinct Leishmania species by multitarget action in the parasites.
- Author
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Antinarelli LMR, Meinel RS, Coelho EAF, da Silva AD, and Coimbra ES
- Subjects
- Animals, Antiprotozoal Agents administration & dosage, Antiprotozoal Agents chemistry, Disease Models, Animal, Female, Hydrazones administration & dosage, Hydrazones chemistry, Hydrazones pharmacology, Imines administration & dosage, Imines chemistry, Imines pharmacology, Inhibitory Concentration 50, Leishmaniasis parasitology, Macrophages drug effects, Mice, Mice, Inbred BALB C, Phosphorylcholine analogs & derivatives, Phosphorylcholine pharmacology, Reactive Oxygen Species metabolism, Resveratrol administration & dosage, Resveratrol analogs & derivatives, Antiprotozoal Agents pharmacology, Leishmania drug effects, Leishmaniasis drug therapy, Resveratrol pharmacology
- Abstract
Objectives: The in vitro antileishmanial effect of analogues of resveratrol (AR) present in the N-aryl imines and N-aryl hydrazones series was investigated. In addition, possible parasite targets were evaluated., Methods: Antipromastigote activity of Leishmania amazonensis, L. braziliensis and L. infantum, as well as the cytotoxicity on macrophages was determined by MTT assay and L. braziliensis-infected macrophages effect by Giemsa stain. After staining, effects on the parasite targets were analysed by flow cytometry or by fluorescence microscopy., Key-Findings: Among the tested compounds, the derivative AR26 showed the best effect against promastigotes of all Leishmania species (IC
50 < 3.0 µg/ml), being more active than miltefosine, the control drug. AR26 was also effective against amastigotes of L. braziliensis (IC50 = 15.9 µg/ml), with low toxicity to mammalian cells. The evaluation of mechanism of action of AR26 on L. braziliensis promastigotes indicates mitochondrial potential depolarization, plasma membrane permeabilization, interference in the progression of the cell cycle and accumulation of autophagic vacuoles. In addition, any increase of the reactive oxygen species levels was detected in the treated L. braziliensis-macrophages., Conclusions: Data indicate that the antileishmanial activity of AR26 is related to multitarget action, and the resveratrol analogues could be used in future studies as antileishmanial agent., (© 2019 Royal Pharmaceutical Society.)- Published
- 2019
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36. Trypanosoma evansi impacts on embryonic neural progenitor cell functions.
- Author
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Fracasso M, Pillat MM, Bottari NB, da Silva AD, Grando TH, Matos AFIM, Petry LS, Ulrich H, de Andrade CM, Monteiro SG, and Da Silva AS
- Subjects
- Animals, Cell Differentiation, Mice, Host-Pathogen Interactions, Neural Stem Cells parasitology, Neural Stem Cells pathology, Trypanosoma growth & development
- Abstract
Trypanosoma evansi appears to have a significant tropism for brain tissue in its chronic and acute phases. The most common symptoms of this brain infection are motor incoordination, meningoencephalitis, demyelination, and anemia. There have only been few studies of the effects of T. evansi infection on neuronal differentiation and brain plasticity. Here, we investigated the impact of the congenital T. evansi infection on brain development in mice. We collected telencephalon-derived neural progenitor cells (NPCs) from T. evansi uninfected and infected mice, and cultivated them into neurospheres. We found that T. evansi significantly decreased the number of cells during development of neurospheres. Analysis of neurosphere differentiation revealed that T. evansi infection significantly increased neural migration. We also observed that T. evansi promoted expression of glial fibrillary acidic protein (GFAP) in infected cells. These data suggest that congenital T. evansi infection may affect embryonic brain development., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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37. Insights about resveratrol analogs against trypanothione reductase of Leishmania braziliensis : Molecular modeling, computational docking and in vitro antileishmanial studies.
- Author
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da Silva AD, Dos Santos JA, Machado PA, Alves LA, Laque LC, de Souza VC, Coimbra ES, and Capriles PVSZ
- Subjects
- Animals, Antioxidants chemistry, Antioxidants pharmacology, Antiprotozoal Agents chemistry, Binding Sites, Leishmaniasis parasitology, Macrophages drug effects, Macrophages enzymology, Macrophages parasitology, Mice, Mice, Inbred BALB C, Models, Molecular, Molecular Docking Simulation, Molecular Structure, NADH, NADPH Oxidoreductases chemistry, Protein Conformation, Protozoan Proteins chemistry, Protozoan Proteins metabolism, Reactive Oxygen Species metabolism, Resveratrol pharmacology, Structure-Activity Relationship, Antiprotozoal Agents pharmacology, Gene Expression Regulation, Enzymologic drug effects, Leishmania braziliensis drug effects, Leishmania braziliensis enzymology, Leishmaniasis drug therapy, NADH, NADPH Oxidoreductases metabolism, Resveratrol chemistry
- Abstract
In this work, we combined molecular modeling, computational docking and in vitro analysis to explore the antileishmanial effect of some resveratrol analogs (ResAn), focusing on their pro-oxidant effect. The molecular target was the trypanothione reductase of Leishmania braziliensis (LbTryR), an essential component of the antioxidant defenses in trypanosomatid parasites. Three-dimensional structures of LbTryR were modeled and molecular docking studies of ResAn1-5 compounds showed the following affinity: ResAn1 > ResAn2 > ResAn4 > ResAn5 > ResAn3. Positive correlation was observed between these compounds' affinity to the LbTryR and the IC
50 values against Leishmania sp (ResAn1 < ResAn2 < ResAn4), which allows for TryR being considered an important target for them. As the compound ResAn1 showed the best antileishmanial activity, and docking studies showed its high affinity for NADP binding site (NS) of TryR, plus having been able to induce ROS production in L. braziliensis promastigotes treated, ResAn1 probably occupies NS interfering in the electron transfer processes responsible for the catalytic reaction. The in silico prediction of ADMET properties suggests that ResAn1 may be a promising drug candidate with properties to cross biological membranes and high gastrointestinal absorption, not violating Lipinski's rules. Ultimately, the antileishmanial effect of ResAn can be associated with a pro-oxidant effect which, in turn, can be exploited as an antimicrobial agent. Communicated by Ramaswamy H. Sarma.- Published
- 2019
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38. Effects of resveratrol on the differentiation fate of neural progenitor cells of mouse embryos infected with Trypanosoma cruzi.
- Author
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Fracasso M, Bottari NB, da Silva AD, Grando TH, Pillat MM, Ulrich H, Vidal T, de Andrade CM, Monteiro SG, Nascimento LFN, Miletti LC, and Schafer da Silva A
- Subjects
- Animals, Chagas Disease drug therapy, Disease Models, Animal, Female, Mice, Neurogenesis drug effects, Neurons cytology, Stem Cells metabolism, Trypanosoma cruzi, Cell Differentiation drug effects, Neurons drug effects, Resveratrol pharmacology, Stem Cells drug effects
- Abstract
Chagas disease (CD) affecting about 7 million people is caused by the flagellate protozoan Trypanosoma cruzi. The central nervous system (CNS) is an important site for T. cruzi persistence in the host during the chronic phase of infection, because the protozoan may pass the blood-brain barrier and may cause motor and cognitive neuronal damage. Thinking about avoiding or minimizing these negative effects, it is hypothesized that resveratrol (RSV), a component with several medicinal properties has beneficial effects on the CNS. The objective of this study was to investigate, whether T. cruzi infection interferes with neurogenesis and gliogenesis of embryos of infected mice females, and whether RSV would be able to avoid or minimize these changes caused by CD. RSV is a polyphenol found in grapes and widely studied for its neuroprotective and antioxidant properties. In addition, we investigated the role caused by the parasite during congenital infection and CNS development. Embryos and their brains were PCR-positive for T. cruzi. For this study, NPCs obtained from telencephalon of infected and uninfected embryos and were cultured in presence of resveratrol for forming neurospheres. The results demonstrated that the congenital transmission of T. cruzi influences CNS formation and neural fate, decreasing the number of neuroespheres and causing an elongation in the phases of the cell cycle. In addition, the parasite promoted an increase in neugliogenesis. Resveratrol was neuroprotective and prevented negative effects of the infection. Thus, we suggest the use of resveratrol as a therapeutic target for the treatment of neuroinflammation or as neuroprotective agent during Chagas disease, as it improves gliogenesis and restores neural migration., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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39. Physical exercise prevents alterations in purinergic system and oxidative status in lipopolysaccharide-induced sepsis in rats.
- Author
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Miron VV, Bottari NB, Assmann CE, Stefanello N, da Costa P, Pelinson LP, Reichert KP, da Silva AD, Lopes TF, da Cruz IBM, Sévigny J, Morsch VM, Schetinger MRC, and Cardoso AM
- Subjects
- Animals, Antioxidants metabolism, Catalase metabolism, Lipid Peroxidation drug effects, Lung drug effects, Lung metabolism, Male, Oxidation-Reduction drug effects, Oxidative Stress drug effects, Rats, Rats, Wistar, Sepsis metabolism, Superoxide Dismutase metabolism, Tumor Necrosis Factor-alpha metabolism, Lipopolysaccharides toxicity, Physical Conditioning, Animal physiology, Sepsis chemically induced, Sepsis prevention & control
- Abstract
Sepsis is a generalized infection that involves alterations in inflammatory parameters, oxidant status, and purinergic signaling in many tissues. Physical exercise has emerged as a tool to prevent this disease because of its anti-inflammatory and antioxidant properties. Thus, in this study, we investigated the effects of physical exercise on preventing alterations in purinergic system components, oxidative stress, and inflammatory parameters in lipopolysaccharide (LPS)-induced sepsis in rats. Male Wistar rats were divided into four groups: control, exercise (EX), LPS, and EX+LPS. The resisted physical exercise was performed for 12 weeks on a ladder with 1 m height. After 72 hours of the last exercise session, the animals received 2.5 mg/kg of LPS for induction of sepsis, and after 24 hours, lungs and blood samples were collected for analysis. The results showed that the exercise protocol used was able to prevent, in septic animals: (1) the increase in body temperature; (2) the increase of lipid peroxidation and reactive species levels in the lung, (3) the increase in adenosine triphosphate levels in serum; (4) the change in the activity of the enzymes ectonucleotidases in lymphocytes, partially; (5) the change in the density of purinergic enzymes and receptors in the lung, and (6) the increase of IL-6 and IL-1β gene expression. Our results revealed the involvement of purinergic signaling and oxidative damage in the mechanisms by which exercise prevents sepsis aggravations. Therefore, the regular practice of physical exercise is encouraged as a better way to prepare the body against sepsis complications., (© 2018 Wiley Periodicals, Inc.)
- Published
- 2019
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40. Antileishmanial activity of a 4-hydrazinoquinoline derivative: Induction of autophagy and apoptosis-related processes and effectiveness in experimental cutaneous leishmaniasis.
- Author
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Antinarelli LMR, de Oliveira Souza I, Zabala Capriles PV, Gameiro J, Britta EA, Nakamura CV, Lima WP, da Silva AD, and Coimbra ES
- Subjects
- Aminoquinolines therapeutic use, Aminoquinolines toxicity, Animals, Antiprotozoal Agents therapeutic use, Antiprotozoal Agents toxicity, Cell Cycle drug effects, Chlorocebus aethiops, Creatinine metabolism, Ear, External parasitology, Ear, External pathology, Female, Inhibitory Concentration 50, Kidney drug effects, Leishmania mexicana cytology, Leishmania mexicana growth & development, Leishmania mexicana ultrastructure, Liver drug effects, Liver enzymology, Mice, Mice, Inbred BALB C, Vero Cells, Aminoquinolines pharmacology, Antiprotozoal Agents pharmacology, Apoptosis drug effects, Autophagy drug effects, Leishmania mexicana drug effects, Leishmaniasis, Cutaneous drug therapy
- Abstract
Currently, available treatment options for leishmaniasis are limited and unsatisfactory. In a previous study, a quinoline derivative (AMQ-j), exhibited a strong effect against Leishmania amazonensis and its antileishmanial activity was preliminarily associated with mitochondrial dysfunction. The present study further explores the antileishmanial effect of this compound against L. amazonensis, as well as determines the main cellular processes involved in the death of the parasite. Moreover, this study evaluated the in vivo effect of the AMQ-j in BALB/c mice experimentally infected by L. amazonensis. The results showed that the compound AMQ-j induces a set of morphological and biochemical features that could correlate with both autophagy-related and apoptosis-like processes, indicating intense mitochondrial swelling, a collapse of the mitochondrial membrane potential, an abnormal chromatin condensation, an externalization of phosphatidylserine, an accumulation of lipid bodies, a disorganization of cell cycle, a formation of autophagic vacuoles, and an increase of acidic compartments. Treatment with AMQ-j through an intralesional route was effective in reducing the parasite burden and size of the lesion. No significant increase in the serum levels of hepatic or renal damage toxicity markers was observed. These findings contribute to the understanding of the mode of action of quinoline derivatives involved in the death of Leishmania parasites and encourage new studies in other experimental models of Leishmania infection., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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41. Novel steroid derivatives: synthesis, antileishmanial activity, mechanism of action, and in silico physicochemical and pharmacokinetics studies.
- Author
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da Trindade Granato J, Dos Santos JA, Calixto SL, Prado da Silva N, da Silva Martins J, da Silva AD, and Coimbra ES
- Subjects
- Administration, Oral, Animals, Cell Cycle Checkpoints drug effects, Cholesterol analogs & derivatives, Cholesterol chemical synthesis, Cholesterol pharmacokinetics, Cholic Acid chemical synthesis, Cholic Acid pharmacokinetics, Cholic Acid pharmacology, Deoxycholic Acid analogs & derivatives, Deoxycholic Acid chemical synthesis, Deoxycholic Acid pharmacokinetics, Dose-Response Relationship, Drug, Leishmania growth & development, Leishmania metabolism, Leishmaniasis parasitology, Macrophages, Peritoneal parasitology, Membrane Potential, Mitochondrial drug effects, Mice, Inbred BALB C, Mitochondria drug effects, Mitochondria metabolism, Models, Biological, Molecular Structure, Oxidative Stress drug effects, Parasitic Sensitivity Tests, Structure-Activity Relationship, Trypanocidal Agents chemical synthesis, Trypanocidal Agents pharmacokinetics, Cholesterol pharmacology, Deoxycholic Acid pharmacology, Drug Discovery methods, Leishmania drug effects, Leishmaniasis drug therapy, Macrophages, Peritoneal drug effects, Trypanocidal Agents pharmacology
- Abstract
The search for new drugs for the treatment of leishmaniasis is an important strategy for improving the current therapeutic arsenal for the disease. There are several limitations to the available drugs including high toxicity, low efficacy, prolonged parenteral administration, and high costs. Steroids are a diverse group of compounds with various applications in pharmacology. However, the antileishmanial activity of this class of molecules has not yet been explored. Therefore, in the present study, we investigated the antileishmanial activity and cytotoxicity of novel steroids against murine macrophages with a focus on the derivatives of cholesterol (CD), cholic acid (CA), and deoxycholic acid (DA). Furthermore, the mechanism of action of the best compound was assessed, and in silico studies to evaluate the physicochemical and pharmacokinetic properties were also conducted. Among the sixteen derivatives, schiffbase2, CD2 and deoxycholic acid derivatives (DOCADs) were effective against promastigotes of Leishmania species. Despite their low toxicity to macrophages, the majority of DOCADs were active against intracellular amastigotes of L. amazonensis, and DOCAD5 exhibited the best biological effect against these parasitic stages (IC
50 = 15.34 μM). Neither the CA derivatives (CAD) nor DA alone inhibited the intracellular parasites. Thus, the absence of hydroxyl in the C-7 position of the steroid nucleus, as well as the modification of the acid group in DOCADs were considered important for antileishmanial activity. The treatment of L. amazonensis promastigote forms with DOCAD5 induced biochemical changes such as depolarization of the mitochondrial membrane potential, increased ROS production and cell cycle arrest. No alterations in parasite plasma membrane integrity were observed. In silico physicochemical and pharmacokinetic studies suggest that DOCAD5 could be a good candidate for an oral drug. The data demonstrate the potential antileishmanial effect of certain steroid derivatives and encourage new in vivo studies., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)- Published
- 2018
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42. Novel organic salts based on quinoline derivatives: The in vitro activity trigger apoptosis inhibiting autophagy in Leishmania spp.
- Author
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Calixto SL, Glanzmann N, Xavier Silveira MM, da Trindade Granato J, Gorza Scopel KK, Torres de Aguiar T, DaMatta RA, Macedo GC, da Silva AD, and Coimbra ES
- Subjects
- Animals, Antiprotozoal Agents chemistry, Antiprotozoal Agents pharmacology, Antiprotozoal Agents therapeutic use, Female, Leishmania growth & development, Leishmania metabolism, Leishmaniasis drug therapy, Leishmaniasis parasitology, Leishmaniasis pathology, Leishmaniasis veterinary, Macrophages cytology, Macrophages drug effects, Macrophages metabolism, Macrophages parasitology, Membrane Potential, Mitochondrial drug effects, Mice, Mice, Inbred BALB C, Oxidative Stress drug effects, Phosphatidylserines metabolism, Phosphorylcholine analogs & derivatives, Phosphorylcholine pharmacology, Phosphorylcholine therapeutic use, Quinolines chemistry, Quinolines therapeutic use, Reactive Oxygen Species metabolism, Salts chemistry, Apoptosis drug effects, Autophagy drug effects, Leishmania drug effects, Quinolines pharmacology
- Abstract
Leishmaniases are infectious diseases, caused by protozoa of the Leishmania genus. These drugs present high toxicity, long-term administration, many adverse effects and are expensive, besides the identification of resistant parasites. In this work, the antileishmanial activity of quinoline derivative salts (QDS) was evaluated, as well as the toxicity on mammalian cells and the mechanism of action of the most promising compound. Among the compound tested, only the compound QDS3 showed activity against promastigotes and amastigotes of Leishmania spp., being more active against the intracellular amastigotes of L. amazonensis-GFP (IC
50 of 5.48 μM). This value is very close to the one observed for miltefosine (IC50 of 4.05 μM), used as control drug. Furthermore, the compound QDS3 exhibited a selective effect, being 40.35 times more toxic to the amastigote form than to the host cell. Additionally, promastigotes of L. amazonensis treated with this compound exhibited characteristics of cells in the process of apoptosis such as mitochondrial membrane depolarization, mitochondrial swelling, increase of ROS production, phosphatidylserine externalization, reduced and rounded shape, and cell cycle alteration. The integrity of the plasma membrane remained unaltered, excluding necrosis in treated promastigotes. The compound QDS3 inhibited the formation of autophagic vacuoles, which may have contributed to parasite death by preventing autophagic mechanisms in the removal of damaged organelles, intensifying the damage caused by the treatment, highlighting the antileishmanial effect of this compound. In addition, treatment with QDS3 induced increased ROS levels in L. amazonensis-infected macrophages, but not in uninfected host cell. These data reinforce that the induction of oxidative stress is one of the main toxic effects caused by the treatment with the compound QDS3 in L. amazonensis, causing irreversible damage and triggering a selective death of intracellular parasites. Data shown here confirm the biological activity of quinoline derivatives and encourage future in vivo studies with this compound in the murine model., (Copyright © 2018 Elsevier B.V. All rights reserved.)- Published
- 2018
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43. In vitro and in vivo anti-inflammatory properties of imine resveratrol analogues.
- Author
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Zimmermann-Franco DC, Esteves B, Lacerda LM, Souza IO, Santos JAD, Pinto NCC, Scio E, da Silva AD, and Macedo GC
- Subjects
- Adjuvants, Immunologic pharmacology, Animals, Anti-Inflammatory Agents pharmacokinetics, Antioxidants pharmacology, Biological Availability, Biphenyl Compounds metabolism, Cell Proliferation drug effects, Cytokines antagonists & inhibitors, Cytokines biosynthesis, Down-Regulation drug effects, Inflammation prevention & control, Inflammation Mediators antagonists & inhibitors, Inflammation Mediators metabolism, Lymphocytes cytology, Lymphocytes drug effects, Major Histocompatibility Complex drug effects, Mice, Mice, Inbred C57BL, Peroxidase biosynthesis, Picrates metabolism, RAW 264.7 Cells, Anti-Inflammatory Agents chemistry, Anti-Inflammatory Agents pharmacology, Imines chemistry, Resveratrol analogs & derivatives
- Abstract
Resveratrol is a natural polyphenol found mainly on red grapes and in red wine, pointed as an important anti-inflammatory/immunomodulatory molecule. However, its bioavailability problems have limited its use encouraging the search for new alternatives agents. Thus, in this study, we synthetize 12 resveratrol analogues (6 imines, 1 thioimine and 5 hydrazones) and investigated its cytotoxicity, antioxidant activity and in vitro anti-inflammatory/immunomodulatory properties. The most promising compounds were also evaluated in vivo. The results showed that imines presented less cytotoxicity, were more effective than resveratrol on DPPH scavenger and exhibited an anti-inflammatory profile. Among them, the imines with a radical in the para position, on the ring B, not engaged in an intramolecular hydrogen-interaction, showed more prominent anti-inflammatory activity modulating, in vivo, the edema formation, the inflammatory infiltration and cytokine levels. An immunomodulatory activity also was observed in these molecules. Thus, our results suggest that imines with these characteristics presents potential to control inflammatory disorders., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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44. Correlation of structural features of novel 1,2,3-triazoles with their neurotoxic and tumoricidal properties.
- Author
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de Souza-Fagundes EM, Delp J, Prazeres PDM, Marques LB, Carmo AML, Stroppa PHF, Glanzmann N, Kisitu J, Szamosvàri D, Böttcher T, Leist M, and da Silva AD
- Subjects
- Animals, Cell Line, Tumor, Cell Survival drug effects, Clone Cells, Dopaminergic Neurons drug effects, Dopaminergic Neurons metabolism, Humans, Neurites drug effects, Neurites metabolism, Triazoles chemical synthesis, Neoplasms pathology, Neurotoxins toxicity, Triazoles chemistry, Triazoles toxicity
- Abstract
Triazoles are interesting templates for novel chemotherapeutic drugs. We synthesized here 17 1,3,4-substituted-1,2,3-triazoles that differed in their 1'-substituent (variable alkyl chain lengths C3-C12), the 3'-substituent (no substituent, -methyl or -propyl) or the salt form obtained. Several of the compounds were cytotoxic (μM range) for tumor cells (HL-60, Jurkat, MCF-7, HCT-116), and when the effect was compared to non-transformed cells (Vero), selectivity ratios of up to 23-fold were obtained. To estimate the liability of these potential drug candidates for triggering neurotoxicity, we used the LUHMES cell-based NeuriTox assay. This test quantifies damage to the neurites of human neurons. The four most potent tumoricidal compounds were found to be neurotoxic in a concentration range similar to the one showing tumor cell toxicity. As the neurites of the LUHMES neurons were affected at >4-fold lower concentrations than the overall cell viability, the novel triazoles were classified as specific neurotoxicants. The structure-activity relationship (SAR) for neurotoxicity was sharply defined and correlated with the one for anti-neoplastic activity. Based on this SAR, two non-neurotoxic compounds were predicted, and testing in the NeuriTox assay confirmed this prediction. In summary, the panel of novel triazoles generated and characterized here, allowed to define structural features associated with cytotoxicity and neurotoxicity. Moreover, the study shows that potential neurotoxic side effects may be predicted early in drug development if highly sensitive test methods for neurite integrity are applied., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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45. Synthesis, characterization, and NMR studies of 1,2,3-triazolium ionic liquids: a good perspective regarding cytotoxicity.
- Author
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Glanzmann N, Carmo AML, Antinarelli LMR, Coimbra ES, Costa LAS, and da Silva AD
- Subjects
- Animals, Cell Survival drug effects, Macrophages drug effects, Mice, Models, Molecular, Molecular Structure, Triazoles chemical synthesis, Triazoles pharmacology, Ionic Liquids chemistry, Magnetic Resonance Spectroscopy, Triazoles chemistry
- Abstract
Ionic liquids (ILs) have been extensively studied and are considered green solvents capable of replacing traditional organic solvents. In this study, seven 1,2,3-triazolium derivative ILs have been synthesized. In order to study the effect of the cation nature on the ILs cytotoxicity, their structures were first identified by
1 H,13 C NMR 1D, and 2D spectroscopy. DFT calculations have also been performed in a way to help to provide an insightful structural analysis from13 C NMR spectroscopy. The comparison made with the NMR experimental shifts was quite important to show that the 1,2,3-triazolium derivatives have the expected structure shown here. The in vitro cytotoxicity of ILs toward macrophages showed that among the compounds tested, five did not exhibit expressive cytotoxicity on mammalian cells. Besides the well-established relationship between the carbonic chain size of the cation and the cytotoxicity, the log P of the compounds predicts that the toxicity increases with the size of the carbon chain, demonstrating that the most cytotoxic compound is also the most lipophilic one. The low cytotoxicity effect of ILs on mammalian cells points to their potential application in large-scale by industry. Graphical abstract Seven triazolium ILs were synthesized and their in vitro cytotoxicity on murine macrophages showed a relationship with the carbonic chain size.- Published
- 2018
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46. C2'-F Stereoconfiguration As a Puckering Switch for Base Stacking at the Dinucleotide Level.
- Author
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Moriou C, Da Silva AD, Vianelli Prado MJ, Denhez C, Plashkevych O, Chattopadhyaya J, Guillaume D, and Clivio P
- Abstract
Fluorine configuration at C2' of the bis(2'-fluorothymidine) dinucleotide is demonstrated to drive intramolecular base stacking. 2'-β F-Configuration drastically reduces stacking compared to the 2'-α series. Hence, base stacking emerges as being tunable by the C2'-F stereoconfiguration through dramatic puckering variations scrutinized by NMR and natural bond orbital analysis. Accordingly, 2'-β F-isomer photoreactivity is significantly reduced compared to that of the 2'-α F-isomer.
- Published
- 2018
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47. Epithelial oral mucosal cells: Do they behave differently when exposed to oral carcinogens?
- Author
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da Silva AD, Daroit NB, Cardoso FB, Laureano NK, Maraschin BJ, Bündrich L, Danilevicz CK, Magnusson AS, Visioli F, and Rados PV
- Subjects
- Antigens, CD biosynthesis, Cadherins biosynthesis, Cell Proliferation drug effects, Female, Humans, Leukoplakia, Oral metabolism, Leukoplakia, Oral pathology, Male, Mouth Neoplasms metabolism, Precancerous Conditions metabolism, Protein Precursors biosynthesis, Squamous Cell Carcinoma of Head and Neck metabolism, Tumor Cells, Cultured, Carcinogenesis drug effects, Carcinogens toxicity, Mouth Neoplasms pathology, Precancerous Conditions pathology, Squamous Cell Carcinoma of Head and Neck pathology
- Abstract
Objective: To assess the level of maturation and proliferation of epithelial cells and the correlation with immunocytochemical expression of adhesion (E-cadherin) and cell differentiation (involucrin) markers., Methods: Cytopathological samples were obtained from four groups of patients: control (CG, n=30); alcohol/tobacco (ATG, n=31), leucoplakia (LG, n=31), and squamous cell carcinoma (SCCG, n=22). Cytopathological smears were collected from all groups for AgNOR, Papanicolaou and immunocytochemical staining., Results: There was an increase in anucleated cells in ATG compared to CG and in LG compared to lesion-free groups (P<.05). In addition, there was a higher rate of intermediate cells in lesion-free groups than in LG (P=.001). When these findings were correlated with positive E-cadherin expression, there was a smaller number of anucleated and intermediate cells (P<.05). The proliferation rate was higher in the SCCG than in the CG (P<.05) and in the ATG compared to LG (P<.05). Moreover, cell proliferation increased in the presence of positive E-cadherin expression in the ATG and LG. No statistically significant results were obtained for involucrin analysis., Conclusion: Cytopathology combined with quantitative techniques such as Papanicolaou, AgNOR, and immunocytochemical expression of E-cadherin detects changes associated with oral carcinogenesis. The innovative approach used in this study allows assessing the expression of cell adhesion (E-cadherin) and differentiation (involucrin) markers by means of oral mucosal cytopathology. The E-cadherin imunocytochemical expression indicated changes associated with the oral carcinogenesis process. An increase in cell proliferation rate in oral squamous cell carcinoma group was associated with the lower immunoexpression of E-cadherin. Cytopathology combined with quantitative techniques and immunocytochemical expression of E-cadherin may detect early alterations associated with oral carcinogenesis., (© 2017 John Wiley & Sons Ltd.)
- Published
- 2018
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48. Erratum to: VOSalophen: a vanadium complex with a stilbene derivative-induction of apoptosis, autophagy, and efficiency in experimental cutaneous leishmaniasis.
- Author
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Machado PA, Moraes JOF, Carvalho GSG, Lima WP, Macedo GC, Britta EA, Nakamura CV, da Silva AD, Cuin A, and Coimbra ES
- Published
- 2017
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49. VOSalophen: a vanadium complex with a stilbene derivative-induction of apoptosis, autophagy, and efficiency in experimental cutaneous leishmaniasis.
- Author
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Machado PA, Moraes JOF, Carvalho GSG, Lima WP, Macedo GC, Britta EA, Nakamura CV, da Silva AD, Cuin A, and Coimbra ES
- Subjects
- Animals, DNA Fragmentation drug effects, Disease Models, Animal, Female, Leishmaniasis, Cutaneous genetics, Mice, Mice, Inbred BALB C, Organometallic Compounds therapeutic use, Apoptosis drug effects, Autophagy drug effects, Leishmaniasis, Cutaneous drug therapy, Leishmaniasis, Cutaneous pathology, Organometallic Compounds chemistry, Organometallic Compounds pharmacology, Stilbenes chemistry, Vanadium chemistry
- Abstract
In our previous work, we demonstrated the promising in vitro effect of VOSalophen, a vanadium complex with a stilbene derivative, against Leishmania amazonensis. Its antileishmanial activity has been associated with oxidative stress in L. amazonensis promastigotes and L. amazonensis-infected macrophages. In the present study, the mechanism involved in the death of parasites after treatment with VOSalophen, as well as in vivo effect in the murine model cutaneous leishmaniasis, has been investigated. Promastigotes of L. amazonensis treated with VOSalophen presented apoptotic cells features, such as cell volume decrease, phosphatidylserine externalization, and DNA fragmentation. An increase in autophagic vacuoles formation in treated promastigotes was also observed, showing that autophagy also may be involved in the death of these parasites. In intracellular amastigotes, DNA fragmentation was observed after treatment with VOSalophen, but this effect was not observed in host cells, highlighting the selective effect of this vanadium complex. In addition, VOSalophen showed activity in the murine model of cutaneous leishmaniasis, without hepatic and renal damages. The outcome described here points out that VOSalophen had promising antileishmanial properties and these data also contribute to the understanding of the mechanisms involved in the death of protozoa induced by metal complexes.
- Published
- 2017
- Full Text
- View/download PDF
50. Oxidative stress in dairy cows naturally infected with the lungworm Dictyocaulus viviparus (Nematoda: Trichostrongyloidea).
- Author
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da Silva AD, da Silva AS, Baldissera MD, Schwertz CI, Bottari NB, Carmo GM, Machado G, Lucca NJ, Henker LC, Piva MM, Giacomin P, Morsch VM, Schetinger MRC, da Rosa RA, and Mendes RE
- Subjects
- Animals, Bronchi parasitology, Catalase blood, Cattle, Cattle Diseases parasitology, Feces parasitology, Lung parasitology, Parasite Egg Count, Reactive Oxygen Species blood, Superoxide Dismutase blood, Thiobarbituric Acid Reactive Substances analysis, Cattle Diseases pathology, Dictyocaulus isolation & purification, Dictyocaulus Infections pathology, Oxidative Stress
- Abstract
The aim of this study was to analyse the oxidative and anti-oxidant status in serum samples from dairy cows naturally infected by Dictyocaulus viviparus and its relation with pathological analyses. The diagnosis of the disease was confirmed by necropsy of one dairy cow with heavy infection by the parasite in the lungs and bronchi. Later, blood and faeces were collected from another 22 cows from the same farm to measure reactive oxygen species (ROS) levels, thiobarbituric acid-reactive substances (TBARS), catalase (CAT) and superoxide dismutase (SOD) activities on day 0 (pre-treatment) and day 10 (post-treatment with eprinomectin). Faecal examination confirmed the infection in all lactating cows. However, the number of D. viviparus larvae per gram of faeces varied between animals. Cows showed different degrees of severity according to respiratory clinical signs of the disease (cough and nasal secretion). Further, they were classified and divided into two groups: those with mild (n = 10) and severe disease (n = 12). Increased levels of TBARS (P < 0.001), ROS (P = 0.002) and SOD activity (P < 0.001), as well as reduced CAT activity (P < 0.001) were observed in cows with severe clinical signs of the disease compared to those with mild clinical signs. Eprinomectin treatment (day 10) caused a reduction of ROS levels (P = 0.006) and SOD activity (P < 0.001), and an increase of CAT activity (P = 0.05) compared to day 0 (pre-treatment). TBARS levels did not differ with treatment (P = 0.11). In summary, increased ROS production and lipid peroxidation altered CAT and SOD activities, as an adaptive response against D. viviparus infection, contributing to the occurrence of oxidative stress and severity of the disease. Treatment with eprinomectin eliminated the infection, and thus minimized oxidative stress in dairy cows.
- Published
- 2017
- Full Text
- View/download PDF
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