30 results on '"Ramos GS"'
Search Results
2. Randomized Trial of Thymectomy in Myasthenia Gravis
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Wolfe, Gi, Kaminski, Hj, Aban, Ib, Minisman, G, Kuo, Hc, Marx, A, Ströbel, P, Mazia, C, Oger, J, Cea, Jg, Heckmann, Jm, Evoli, A, Nix, W, Ciafaloni, E, Antonini, G, Witoonpanich, R, King, Jo, Beydoun, Sr, Chalk, Ch, Barboi, Ac, Amato, Aa, Shaibani, Ai, Katirji, B, Lecky, Br, Buckley, C, Vincent, A, Dias Tosta, E, Yoshikawa, H, Waddington Cruz, M, Pulley, Mt, Rivner, Mh, Kostera Pruszczyk, A, Pascuzzi, Rm, Jackson, Ce, Garcia Ramos GS, Verschuuren, Jj, Massey, Jm, Kissel, Jt, Werneck, Lc, Benatar, M, Barohn, Rj, Tandan, R, Mozaffar, T, Conwit, R, Odenkirchen, J, Sonett, Jr, 3rd, Jaretzki A., Newsom Davis, J, Cutter, Gr, MGTX study group including Cutter GR, Feese, M, Saluto, V, Rosenberg, M, Alvarez, V, Rey, L, King, J, Butzkueven, H, Goldblatt, J, Carey, J, Pollard, J, Reddel, S, Handel, N, Mccaughan, B, Pallot, L, Novis, R, Boasquevisque, C, Morato Fernandez, R, Ximenes, M, Werneck, L, Scola, R, Soltoski, P, Chalk, C, Moore, F, Mulder, D, Wadup, L, Mezei, M, Evans, K, Jiwa, T, Schaffar, A, White, C, Toth, C, Gelfand, G, Wood, S, Pringle, E, Zwicker, J, Maziak, D, Shamji, F, Sundaresan, S, Seely, A, Cea, G, Verdugo, R, Aguayo, A, Jander, S, Zickler, P, Klein, M, Weis, Ca, Melms, A, Bischof, F, Aebert, H, Ziemer, G, Thümler, B, Wilhem Schwenkmezger, T, Mayer, E, Schalke, B, Pöschel, P, Hieber, G, Wiebe, K, Clemenzi, A, Ceschin, V, Rendina, E, Venuta, F, Morino, S, Bucci, E, Durelli, Luca, Tavella, A, Clerico, Marinella, Contessa, G, Borasio, P, Servidei, S, Granone, P, Mantegazza, R, Berta, E, Novellino, L, Spinelli, L, Motomura, M, Matsuo, H, Nagayasu, T, Takamori, M, Oda, M, Matsumoto, I, Furukawa, Y, Noto, D, Motozaki, Y, Iwasa, K, Yanase, D, Ramos, Gg, Cacho, B, de la Garza, L, Lipowska, M, Kwiecinski, H, Potulska Chromik, A, Orlowski, T, Silva, A, Feijo, M, Freitas, A, Heckmann, J, Frost, A, Pan, El, Tucker, L, Rossouw, J, Drummond, F, Illa, I, Diaz, J, Leon, C, Yeh, Jh, Chiu, Hc, Hsieh, Ys, Tunlayadechanont, S, Attanavanich, S, Verschuuren, J, Straathof, C, Titulaer, M, Versteegh, M, Pels, A, Krum, Y, Leite, M, Hilton Jones, D, Ratnatunga, C, Farrugia, Me, Petty, R, Overell, J, Kirk, A, Gibson, A, Mcdermott, C, Hopkinson, D, Lecky, B, Watling, D, Marshall, D, Saminaden, S, Davies, D, Dougan, C, Sathasivam, S, Page, R, Sussman, J, Ealing, J, Krysiak, P, Amato, A, Salajegheh, M, Jaklitsch, M, Roe, K, Ashizawa, T, Smith, Rg, Zwischenberg, J, Stanton, P, Barboi, A, Jaradeh, S, Tisol, W, Gasparri, M, Haasler, G, Yellick, M, Dennis, C, Barohn, R, Pasnoor, M, Dimachkie, M, Mcvey, A, Gronseth, G, Dick, A, Kramer, J, Currence, M, Herbelin, L, Belsh, J, Li, G, Langenfeld, J, Mertz, Ma, Harrison, T, Force, S, Usher, S, Beydoun, S, Lin, F, Demeester, S, Akhter, S, Malekniazi, A, Avenido, G, Crum, B, Milone, M, Cassivi, S, Fisher, J, Heatwole, C, Watson, T, Hilbert, J, Smirnow, A, Distad, B, Weiss, M, Wood, D, Haug, J, Ernstoff, R, Cao, J, Chmielewski, G, Welsh, R, Duris, R, Gutmann, L, Pawar, G, Graeber, Gm, Altemus, P, Nance, C, Jackson, C, Grogan, P, Calhoon, J, Kittrell, P, Myers, D, Kaminski, H, Hayat, G, Naunheim, K, Eller, S, Holzemer, E, Alshekhlee, A, Robke, J, Karlinchak, B, Katz, J, Miller, R, Roan, R, Forshew, D, Kissel, J, Elsheikh, B, Ross, P, Chelnick, S, Lewis, R, Acsadi, A, Baciewicz, F, Masse, S, Massey, J, Juel, V, Onaitis, M, Lowe, J, Lipscomb, B, Thai, G, Milliken, J, Martin, V, Karayan, R, Muley, S, Parry, G, Shumway, S, Oh, S, Claussen, G, Lu, L, Cerfolio, R, Young, A, Morgan, M, Pascuzzi, R, Kincaid, J, Kesler, K, Guingrich, S, Michaels, A, Phillips, L, Burns, T, Jones, D, Fischer, C, Pulley, M, Berger, A, D'Agostino, H, Smith, L, Rivner, M, Pruitt, J, Landolfo, K, Hillman, D, Shaibani, A, Sermas, A, Ruel, R, Ismail, F, Sivak, M, Goldstein, M, Camunas, J, Bratton, J, Panitch, H, Leavitt, B, Jones, M, Wolfe, G, Muppidi, S, Vernino, S, Nations, S, Meyer, D, and Gorham, N.
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Male ,medicine ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Medical and Health Sciences ,Severity of Illness Index ,law.invention ,0302 clinical medicine ,Randomized controlled trial ,law ,Prednisone ,Adolescent ,Adult ,Aged ,Combined Modality Therapy ,Female ,Glucocorticoids ,Hospitalization ,Humans ,Middle Aged ,Myasthenia Gravis ,Single-Blind Method ,Treatment Outcome ,Young Adult ,Thymectomy ,Medicine (all) ,Young adult ,MGTX Study Group ,General Medicine ,Settore MED/26 - NEUROLOGIA ,6.1 Pharmaceuticals ,medicine.drug ,medicine.medical_specialty ,Clinical Trials and Supportive Activities ,Autoimmune Disease ,03 medical and health sciences ,Rare Diseases ,Clinical Research ,General & Internal Medicine ,Internal medicine ,Severity of illness ,business.industry ,Neurosciences ,Evaluation of treatments and therapeutic interventions ,Retrospective cohort study ,medicine.disease ,Myasthenia gravis ,Surgery ,Clinical research ,adolescent ,adult ,aged ,combined modality therapy ,female ,glucocorticoids ,hospitalization ,humans ,male ,middle aged ,myasthenia gravis ,prednisone ,severity of Illness index ,single-blind method ,treatment outcome ,young adult ,thymectomy ,business ,030217 neurology & neurosurgery - Abstract
BackgroundThymectomy has been a mainstay in the treatment of myasthenia gravis, but there is no conclusive evidence of its benefit. We conducted a multicenter, randomized trial comparing thymectomy plus prednisone with prednisone alone.MethodsWe compared extended transsternal thymectomy plus alternate-day prednisone with alternate-day prednisone alone. Patients 18 to 65 years of age who had generalized nonthymomatous myasthenia gravis with a disease duration of less than 5 years were included if they had Myasthenia Gravis Foundation of America clinical class II to IV disease (on a scale from I to V, with higher classes indicating more severe disease) and elevated circulating concentrations of acetylcholine-receptor antibody. The primary outcomes were the time-weighted average Quantitative Myasthenia Gravis score (on a scale from 0 to 39, with higher scores indicating more severe disease) over a 3-year period, as assessed by means of blinded rating, and the time-weighted average required dose of prednisone over a 3-year period.ResultsA total of 126 patients underwent randomization between 2006 and 2012 at 36 sites. Patients who underwent thymectomy had a lower time-weighted average Quantitative Myasthenia Gravis score over a 3-year period than those who received prednisone alone (6.15 vs. 8.99, P
- Published
- 2016
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3. First report of the association between Wolbachia and Cotesia flavipes (Hymenoptera: Braconidae): effect on life history parameters of the parasitoid.
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Silva NNP, Carvalho VR, Silva CB, Bomfim JPA, Ramos GS, and Oliveira RC
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- Animals, Female, Male, RNA, Ribosomal, 16S analysis, Larva microbiology, Larva growth & development, Larva parasitology, Life History Traits, Moths parasitology, Moths microbiology, Wolbachia physiology, Wolbachia genetics, Symbiosis, Wasps physiology, Wasps microbiology
- Abstract
The symbiosis between microorganisms and host arthropods can cause biological, physiological, and reproductive changes in the host population. The present study aimed to survey facultative symbionts of the genera Wolbachia , Arsenophonus , Cardinium , Rickettsia , and Nosema in Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) and Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) in the laboratory and evaluate the influence of infection on the fitness of these hosts. For this purpose, 16S rDNA primers were used to detect these facultative symbionts in the host species, and the hosts' biological and morphological features were evaluated for changes resulting from the infection caused by these microorganisms. The bacterial symbionts studied herein were not detected in the D. saccharalis samples analysed, but the endosymbiont Wolbachia was detected in C. flavipes and altered the biological and morphological aspects of this parasitoid insect. The results of this study may help to elucidate the role of Wolbachia in maintaining the quality of populations/lineages of C. flavipes .
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- 2024
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4. A three-dimensional cell culture approach to investigate cytotoxic effects and production of inflammatory mediators by epoxy resin-based and calcium silicate-based endodontic sealer.
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Scelza MFZ, Tavares SJO, Scelza P, Ramos GS, Lima Aboud LR, Piasecki L, Leite PEC, Silva JDD, Soares-Lima SC, and Alves GG
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- Humans, Cell Culture Techniques, Three Dimensional methods, Inflammation Mediators metabolism, Microscopy, Fluorescence, Osteoblasts drug effects, Root Canal Filling Materials pharmacology, Epoxy Resins, Calcium Compounds pharmacology, Silicates pharmacology, Cell Survival drug effects, Materials Testing
- Abstract
Objectives: The aim of the present study was to assess the cytocompatibility of epoxy resin-based AH Plus Jet (Dentsply De Trey, Konstanz, Germany), Sealer Plus (MK Life, Porto Alegre, Brazil), calcium silicate-based Bio-C Sealer (Angelus, Londrina, PR, Brazil), Sealer Plus BC (MK Life) and AH Plus BC (Dentsply) through a tridimensional (3D) culture model of human osteoblast-like cells., Methods: Spheroids of MG-63 cells were produced and exposed to fresh root canal sealers extracts by 24 h, and the cytotoxicity was assessed by the Lactate Dehydrogenase assay (LDH). The distribution of dead cells within the microtissue was assessed by fluorescence microscopy, and morphological effects were investigated by histological analysis. The secreted inflammatory mediators were detected in cell supernatants through flow luminometry (XMap Luminex)., Results: Cells incubated with AH Plus Jet, AH Plus BC, Sealer Plus BC and Bio-C Sealer extracts showed high rates of cell viability, while the Sealer Plus induced a significant reduction of cell viability, causing reduction on the spheroid structure. Sealer Plus and Seaker Plus BC caused alterations on 3D microtissue morphology. The AH Plus BC extract was associated with the downregulation of secretion of pro-inflammatory cytokines IL-5, IL-7, IP-10 and RANTES., Conclusions: The new AH Plus BC calcium silicate-based endodontic sealer did not reduce cell viability in vitro, while led to the downregulation of pro-inflammatory cytokines., Clinical Significance: Choosing the appropriate endodontic sealer is a crucial step. AH Plus BC demonstrated high cell viability and downregulation of pro-inflammatory cytokines, appearing reliable for clinical use, while Sealer Plus presented lower cytocompatibility., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2024
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5. A novel sEMG data augmentation based on WGAN-GP.
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Coelho F, Pinto MF, Melo AG, Ramos GS, and Marcato ALM
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- Electromyography methods, Movement, Neural Networks, Computer, Artificial Limbs
- Abstract
The classification of sEMG signals is fundamental in applications that use mechanical prostheses, making it necessary to work with generalist databases that improve the accuracy of those classifications. Therefore, synthetic signal generation can be beneficial in enriching a database to make it more generalist. This work proposes using a variant of generative adversarial networks to produce synthetic biosignals of sEMG. A convolutional neural network (CNN) was used to classify the movements. The results showed good performance with an increase of 4.07% in a set of movement classification accuracy when 200 synthetic samples were included for each movement. We compared our results to other methodologies, such as Magnitude Warping and Scaling. Both methodologies did not have the same performance in the classification.
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- 2023
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6. Supramolecular assemblies from antimony(V) complexes for the treatment of leishmaniasis.
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Demicheli C, Vallejos VMR, Lanza JS, Ramos GS, Do Prado BR, Pomel S, Loiseau PM, and Frézard F
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The pentavalent meglumine antimoniate (MA) is still a first-line drug in the treatment of leishmaniasis in several countries. As an attempt to elucidate its mechanism of action and develop new antimonial drugs with improved therapeutic profile, Sb(V) complexes with different ligands, including β-cyclodextrin (β-CD), nucleosides and non-ionic surfactants, have been studied. Interestingly, Sb(V) oxide, MA, its complex with β-CD, Sb(V)-guanosine complex and amphiphilic Sb(V) complexes with N-alkyl-N-methylglucamide, have shown marked tendency to self-assemble in aqueous solutions, forming nanoaggregates, hydrogel or micelle-like nanoparticles. Surprisingly, the resulting assemblies presented in most cases slow dissociation kinetics upon dilution and a strong influence of pH, which impacted on their pharmacokinetic and therapeutic properties against leishmaniasis. To explain this unique property, we raised the hypothesis that multiple pnictogen bonds could contribute to the formation of these assemblies and their kinetic of dissociation. The present article reviews our current knowledge on the structural organization and physicochemical characteristics of Sb-based supramolecular assemblies, as well as their pharmacological properties and potential for treatment of leishmaniasis. This review supports the feasibility of the rational design of new Sb(V) complexes with supramolecular assemblies for the safe and effective treatment of leishmaniasis., Competing Interests: Conflict of interestThe authors declare no competing interests., (© International Union for Pure and Applied Biophysics (IUPAB) and Springer-Verlag GmbH Germany, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)
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- 2023
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7. Liposomal Amphotericin B for Treatment of Leishmaniasis: From the Identification of Critical Physicochemical Attributes to the Design of Effective Topical and Oral Formulations.
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Frézard F, Aguiar MMG, Ferreira LAM, Ramos GS, Santos TT, Borges GSM, Vallejos VMR, and De Morais HLO
- Abstract
The liposomal amphotericin B (AmB) formulation, AmBisome
® , still represents the best therapeutic option for cutaneous and visceral leishmaniasis. However, its clinical efficacy depends on the patient's immunological status, the clinical manifestation and the endemic region. Moreover, the need for parenteral administration, its side effects and high cost significantly limit its use in developing countries. This review reports the progress achieved thus far toward the understanding of the mechanism responsible for the reduced toxicity of liposomal AmB formulations and the factors that influence their efficacy against leishmaniasis. It also presents the recent advances in the development of more effective liposomal AmB formulations, including topical and oral liposome formulations. The critical role of the AmB aggregation state and release rate in the reduction of drug toxicity and in the drug efficacy by non-invasive routes is emphasized. This paper is expected to guide future research and development of innovative liposomal formulations of AmB.- Published
- 2022
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8. Nanoassemblies from Amphiphilic Sb Complexes Target Infection Sites in Models of Visceral and Cutaneous Leishmaniases.
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Lanza JS, Vallejos VMR, Ramos GS, de Oliveira ACB, Demicheli C, Rivas L, Pomel S, Loiseau PM, and Frézard F
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This work aims to evaluate whether nanoassemblies (NanoSb) made from antimony(V) complexes with octanoyl- N -methylglucamide (SbL8) or decanoyl- N -methylglucamide (SbL10) would effectively target the infection sites in visceral and cutaneous leishmaniases (VL and CL). NanoSb were investigated regarding stability at different pHs, accumulation of Sb in the macrophage host cell and liver, and in vitro and in vivo activities in models of leishmaniasis. The kinetic stability assay showed that NanoSb are stable at neutral pH, but release incorporated lipophilic substance after conformational change in media that mimic the gastric fluid and the parasitophorous vacuole. NanoSb promoted greater accumulation of Sb in macrophages and in the liver of mice after parenteral administration, when compared to conventional antimonial Glucantime
® . SbL10 was much more active than Glucantime® against intramacrophage Leishmania amastigotes and less cytotoxic than SbL8 against macrophages. The in vitro SbL10 activity was further enhanced with co-incorporated miltefosine. NanoSb showed high antileishmanial activity in the L. donovani murine VL after parenteral administration and moderate activity in the L. amazonensis murine CL after topical treatment. This study supports the ability of NanoSb to effectively deliver a combination of Sb and co-incorporated drug to host cell and infected tissues, in a better way than Glucantime® does.- Published
- 2022
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9. Risk of falls using the Biodex Balance System in non-faller patients with Parkinson Disease.
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Ramos GS, Silva-Batista C, Palma BP, Ugrinowitsch C, and Cunha TFD
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- Humans, Aged, Postural Balance, Rest, Accidental Falls, Parkinson Disease complications
- Abstract
Purpose: Biodex Balance System (BBS) is a low-cost platform used to assess balance in different populations. However, no study has used this tool to evaluate the risk of falls related to balance changes in non-faller individuals with Parkinson Disease (PD)., Objective: The aim of this study was to determine the changes in the balance in non-faller individuals with mild to moderate PD compared to healthy elders., Methods: Forty-six PD patients at stages 2 and 3 were assessed in the 'on' state (fully medicated) as well as 31 age-matched healthy controls. They were submitted to the fall risk protocol of BBS and performed three 20-s trials and a 60-s rest interval between the trials., Results: Non-faller PD patients had an increased instability when compared to the healthy controls in the anteroposterior (controls: 1.54 ± 1.00 vs. PD patients: 2.91 ± 0.93) and mediolateral directions (controls: 1.21 ± 0.57 vs. PD patients: 1.42 ± 0.46), resulting in a great overall instability in the PD patients (controls: 1.28 ± 0.61 vs. PD patients: 4.09 ± 1.22). A significant correlation between overall instability and UPDRS-III (motor symptoms) in individuals with PD was observed., Conclusion: BBS was able to identify the risk of falls in non-fallers, showing that PD patients have a greater risk of falls in unstable conditions than age-matched healthy elders, mainly due to the large sway in the anteroposterior direction. Furthermore, the severity of motor symptoms was related to overall instability which can increase the risk of falls in PD patients.
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- 2022
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10. Formulation of Amphotericin B in PEGylated Liposomes for Improved Treatment of Cutaneous Leishmaniasis by Parenteral and Oral Routes.
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Ramos GS, Vallejos VMR, Borges GSM, Almeida RM, Alves IM, Aguiar MMG, Fernandes C, Guimarães PPG, Fujiwara RT, Loiseau PM, Ferreira LAM, and Frézard F
- Abstract
Liposomal amphotericin B (AmB) or AmBisome
® is the most effective and safe therapeutic agent for visceral leishmaniasis (VL), but its clinical efficacy is limited in cutaneous leishmaniasis (CL) and HIV/VL co-infection. The aim of this work was to develop a formulation of AmB in PEGylated liposomes and compare its efficacy to AmBisome® in a murine model of CL. Formulations of AmB in conventional and PEGylated liposomes were characterized for particle size and morphology, drug encapsulation efficiency and aggregation state. Those were compared to AmBisome® in Leishmania amazonensis -infected BALB/c mice for their effects on the lesion size growth and parasite load. The conventional and PEGylated formulations showed vesicles with 100-130 nm diameter and low polydispersity, incorporating more than 95% of AmB under the non-aggregated form. Following parenteral administration in the murine model of CL, the PEGylated formulation of AmB significantly reduced the lesion size growth and parasite load, in comparison to control groups, in contrast to conventional liposomal AmB. The PEGylated formulation of AmB was also effective when given by oral route on a 2-day regimen. This work reports for the first time that PEGylated liposomal AmB can improve the treatment of experimental cutaneous leishmaniasis by both parenteral and oral routes.- Published
- 2022
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11. Comparative evaluation of meglumine antimoniate encapsulated in a mixture of conventional and PEGylated liposomes and immunotherapy using an anti-canine IL-10 receptor-blocking monoclonal antibody on canine visceral leishmaniasis.
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Cardoso JMO, Brito RCF, Mathias FAS, Reis LES, Vieira JFP, Ostolin TLVDP, Andrade HM, Ramos GS, Frézard F, Aguiar-Soares RDO, Roatt BM, and Reis AB
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- Allopurinol pharmacology, Animals, CD4-Positive T-Lymphocytes drug effects, CD4-Positive T-Lymphocytes metabolism, Dog Diseases metabolism, Dogs, Immunologic Factors metabolism, Immunotherapy methods, Leishmania infantum drug effects, Leishmaniasis, Visceral metabolism, Organometallic Compounds pharmacology, Antibodies, Monoclonal pharmacology, Dog Diseases drug therapy, Leishmaniasis, Visceral drug therapy, Liposomes chemistry, Meglumine Antimoniate pharmacology, Polyethylene Glycols chemistry, Receptors, Interleukin-10 antagonists & inhibitors
- Abstract
This study compared the therapeutic potential of the chemotherapy using meglumine antimoniate encapsulated in a mixture of conventional and PEGylated liposomes (Nano Sb
v ) and immunotherapy with anti-canine IL-10 receptor-blocking monoclonal antibody (Anti IL-10R) on canine visceral leishmaniasis (CVL). Twenty mongrel dogs naturally infected by L. infantum, displaying clinical signs of visceral leishmaniasis were randomly divided in two groups. In the first one, nine dogs received six intravenous doses of a mixture of conventional and PEGylated liposomes containing meglumine antimoniate at 6.5 mg Sb/kg/dose. In the second one, eleven dogs received two intramuscular doses of 4 mg of anti-canine IL-10 receptor-blocking monoclonal antibody. The animals were evaluated before (T0) and 30, 90, and 180 days after treatments. Our major results demonstrated that both treatments were able to maintain hematological and biochemical parameters, increase circulating T lymphocytes subpopulations, increase the IFN-γ producing T-CD4 lymphocytes, restore the lymphoproliferative capacity and improve the clinical status. However, although these improvements were observed in the initial post-treatment times, they did not maintain until the end of the experimental follow-up. We believe that the use of booster doses or the association of chemotherapy and immunotherapy (immunochemotherapy) is promising to improve the effectiveness of treating CVL for improving the clinical signs and possibly reducing the parasite burden in dogs infected with Leishmania infantum., (Copyright © 2021 Elsevier Ltd. All rights reserved.)- Published
- 2022
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12. Starch adulteration in turmeric samples through multivariate analysis with infrared spectroscopy.
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Macêdo IYL, Machado FB, Ramos GS, Costa AGDC, Batista RD, Filho ARG, Asquieri ER, Souza AR, Oliveira AE, and Gil ES
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- 2021
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13. Antileishmanial activity of fullerol and its liposomal formulation in experimental models of visceral leishmaniasis.
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Ramos GS, Vallejos VMR, Ladeira MS, Reis PG, Souza DM, Machado YA, Ladeira LO, Pinheiro MBV, Melo MN, Fujiwara RT, and Frézard F
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- Animals, Cytokines blood, Disease Models, Animal, Drug Compounding, Female, Fullerenes chemistry, Inflammation Mediators blood, Leishmania infantum growth & development, Leishmania mexicana growth & development, Leishmaniasis, Visceral blood, Leishmaniasis, Visceral parasitology, Liposomes, Liver metabolism, Mesocricetus, Mice, Inbred BALB C, Nanoparticles, Parasite Load, Trypanocidal Agents chemistry, Mice, Fullerenes pharmacology, Leishmania infantum drug effects, Leishmania mexicana drug effects, Leishmaniasis, Visceral drug therapy, Lipids chemistry, Liver parasitology, Macrophages, Peritoneal parasitology, Trypanocidal Agents pharmacology
- Abstract
Visceral leishmaniasis (VL) is a systemic parasitic disease that leads to high rates of morbidity and mortality in humans worldwide. There is a great need to develop new drugs and novel strategies to make chemotherapy for this disease more efficacious and well tolerated. Recent reports on the immunomodulatory effects and the low toxicity of the spherical carbon nanostructure fullerol led us to investigate in vitro and in vivo antileishmanial activity in free and encapsulated forms in liposomes. When assayed against intramacrophagic Leishmania amastigotes, fullerol showed a dose-dependent reduction of the infection index with IC
50 of 0.042 mg/mL. When given daily by i.p. route for 20 days (0.05 mg/kg/d) in a murine model of acute VL, fullerol promoted significant reduction in the liver parasite load. To improve the delivery of fullerol to the infection sites, liposomal formulations were prepared by the dehydration-rehydration method. When evaluated in the acute VL model, liposomal fullerol (Lip-Ful) formulations given i.p. at 0.05 and 0.2 mg/kg with 4-days intervals were more effective than the free form, with significant parasite reductions in both liver and spleen. Lip-Ful at 0.2 mg/kg promoted complete parasite elimination in the liver. The antileishmanial activity of Lip-Ful was further confirmed in a chronic model of VL. Lip-Ful was also found to induce secretion of pro-inflammatory TNF-α, IFN-γ and IL-1β cytokines. In conclusion, this work reports for the first time the antileishmanial activity of fullerol and introduces an innovative approach for treatment of VL based on the association of this nanostructure with liposomes., (Copyright © 2020 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)- Published
- 2021
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14. In vitro and in vivo antileishmanial activity of β-acetyl-digitoxin, a cardenolide of Digitalis lanata potentially useful to treat visceral leishmaniasis.
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Freitas CS, Lage DP, Oliveira-da-Silva JA, Costa RR, Mendonça DVC, Martins VT, Reis TAR, Antinarelli LMR, Machado AS, Tavares GSV, Ramos FF, Brito RCF, Ludolf F, Chávez-Fumagalli MA, Roatt BM, Ramos GS, Munkert J, Ottoni FM, Campana PRV, Duarte MC, Gonçalves DU, Coimbra ES, Braga FC, Pádua RM, and Coelho EAF
- Subjects
- Animals, Cardenolides therapeutic use, Digitoxin therapeutic use, Mice, Mice, Inbred BALB C, Antiprotozoal Agents therapeutic use, Digitalis, Leishmania infantum, Leishmaniasis, Visceral drug therapy
- Abstract
Current treatments of visceral leishmaniasis face limitations due to drug side effects and/or high cost, along with the emergence of parasite resistance. Novel and low-cost antileishmanial agents are therefore required. We report herein the antileishmanial activity of β-acetyl-digitoxin (b-AD), a cardenolide isolated from Digitalis lanata leaves, assayed in vitro and in vivo against Leishmania infantum. Results showed direct action of b-AD against parasites, as well as efficacy for the treatment of Leishmania-infected macrophages. In vivo experiments using b-AD-containing Pluronic
® F127 polymeric micelles (b-AD/Mic) to treat L. infantum-infected mice showed that this composition reduced the parasite load in distinct organs in more significant levels. It also induced the development of anti-parasite Th1-type immunity, attested by high levels of IFN-γ, IL-12, TNF-α, GM-CSF, nitrite and specific IgG2a antibodies, in addition to low IL-4 and IL-10 contents, along with higher IFN-γ-producing CD4+ and CD8+ T-cell frequency. Furthermore, low toxicity was found in the organs of the treated animals. Comparing the therapeutic effect between the treatments, b-AD/Mic was the most effective in protecting animals against infection, when compared to the other groups including miltefosine used as a drug control. Data found 15 days after treatment were similar to those obtained one day post-therapy. In conclusion, the results obtained suggest that b-AD/Mic is a promising antileishmanial agent and deserves further studies to investigate its potential to treat visceral leishmaniasis., (© C.S. Freitas et al., published by EDP Sciences, 2021.)- Published
- 2021
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15. Digitoxigenin presents an effective and selective antileishmanial action against Leishmania infantum and is a potential therapeutic agent for visceral leishmaniasis.
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Freitas CS, Oliveira-da-Silva JA, Lage DP, Costa RR, Mendonça DVC, Martins VT, Reis TAR, Antinarelli LMR, Machado AS, Tavares GSV, Ramos FF, Coelho VTS, Brito RCF, Ludolf F, Chávez-Fumagalli MA, Roatt BM, Ramos GS, Munkert J, Ottoni FM, Campana PRV, Humbert MV, Coimbra ES, Braga FC, Pádua RM, and Coelho EAF
- Subjects
- Amphotericin B therapeutic use, Animals, Deoxycholic Acid therapeutic use, Drug Combinations, Female, Liver parasitology, Macrophages drug effects, Macrophages parasitology, Membrane Potential, Mitochondrial drug effects, Mice, Mice, Inbred BALB C, Micelles, Parasite Load, Reactive Oxygen Species, Spleen parasitology, Antiprotozoal Agents therapeutic use, Digitoxigenin therapeutic use, Drug Repositioning methods, Leishmania infantum drug effects, Leishmaniasis, Visceral drug therapy, Poloxamer therapeutic use
- Abstract
Treatment for visceral leishmaniasis (VL) is hampered mainly by drug toxicity, their high cost, and parasite resistance. Drug development is a long and pricey process, and therefore, drug repositioning may be an alternative worth pursuing. Cardenolides are used to treat cardiac diseases, especially those obtained from Digitalis species. In the present study, cardenolide digitoxigenin (DIGI) obtained from a methanolic extract of Digitalis lanata leaves was tested for its antileishmanial activity against Leishmania infantum species. Results showed that 50% Leishmania and murine macrophage inhibitory concentrations (IC
50 and CC50 , respectively) were of 6.9 ± 1.5 and 295.3 ± 14.5 μg/mL, respectively. With amphotericin B (AmpB) deoxycholate, used as a control drug, values of 0.13 ± 0.02 and 0.79 ± 0.12 μg/mL, respectively, were observed. Selectivity index (SI) values were of 42.8 and 6.1 for DIGI and AmpB, respectively. Preliminary studies suggested that the mechanism of action for DIGI is to cause alterations in the mitochondrial membrane potential, to increase the levels of reactive oxygen species and induce accumulation of lipid bodies in the parasites. DIGI was incorporated into Pluronic® F127-based polymeric micelles, and the formula (DIGI/Mic) was used to treat L. infantum-infected mice. Miltefosine was used as a control drug. Results showed that animals treated with either miltefosine, DIGI, or DIGI/Mic presented significant reductions in the parasite load in their spleens, livers, bone marrows, and draining lymph nodes, as well as the development of a specific Th1-type response, when compared with the controls. Results obtained 1 day after treatment were corroborated with data corresponding to 15 days after therapy. Importantly, treatment with DIGI/Mic induced better parasitological and immunological responses when compared with miltefosine- and DIGI-treated mice. In conclusion, DIGI/Mic has the potential to be used as a therapeutic agent to protect against L. infantum infection, and it is therefore worth of consideration in future studies addressing VL treatment.- Published
- 2021
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16. Therapeutic Efficacy of a Mixed Formulation of Conventional and PEGylated Liposomes Containing Meglumine Antimoniate, Combined with Allopurinol, in Dogs Naturally Infected with Leishmania infantum.
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Dos Santos CCP, Ramos GS, De Paula RC, Faria KF, Moreira POL, Pereira RA, Melo MN, Tafuri WL, Demicheli C, Ribeiro RR, Azevedo EG, Do Monte-Neto R, Da Silva SM, and Frézard F
- Subjects
- Allopurinol therapeutic use, Animals, Dogs, Liposomes therapeutic use, Meglumine therapeutic use, Meglumine Antimoniate therapeutic use, Polyethylene Glycols therapeutic use, Antiprotozoal Agents therapeutic use, Dog Diseases drug therapy, Leishmania infantum, Leishmaniasis, Visceral drug therapy, Leishmaniasis, Visceral veterinary, Organometallic Compounds therapeutic use
- Abstract
The treatment of dogs naturally infected with Leishmania infantum using meglumine antimoniate (MA) encapsulated in conventional liposomes (LC) in association with allopurinol has been previously reported to promote a marked reduction in the parasite burden in the main infection sites. Here, a new assay in naturally infected dogs was performed using a novel liposome formulation of MA consisting of a mixture of conventional and long-circulating (PEGylated) liposomes (LCP), with expected broader distribution among affected tissues of the mononuclear phagocyte system. Experimental groups of naturally infected dogs were as follows: LCP plus Allop, receiving LCP intravenously as 2 cycles of 6 doses (6.5 mg Sb/kg of body weight/dose) at 4-day intervals plus allopurinol at 30 mg/kg/12 h per os (p.o.) during 130 days (LCP+Allop); LC plus Allop, receiving LC intravenously as 2 cycles of 6 doses (6.5 mg Sb/kg/dose) plus allopurinol during 130 days (LC+Allop); Allop, treated with allopurinol only; and a nontreated control. Parasite loads were evaluated by quantitative PCR in liver, spleen, and bone marrow tissue and by immunohistochemistry in the ear skin, before treatment, just after treatment, and 4 months later. The LCP+Allop and LC+Allop groups, but not the Allop group, showed significant suppression of the parasites in the liver, spleen, and bone marrow 4 months after treatment compared to the pretreatment period or the control group. Only LCP+Allop group showed significantly lower parasite burden in the skin in comparison to the control group. On the basis of clinical staging and parasitological evaluations, the LCP formulation exhibited a more favorable therapeutic profile than the LC one, being therefore promising for the treatment of canine visceral leishmaniasis., (Copyright © 2020 American Society for Microbiology.)
- Published
- 2020
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17. Elucidation of the mechanism of anti-herpes action of two novel semisynthetic cardenolide derivatives.
- Author
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Boff L, Schneider NFZ, Munkert J, Ottoni FM, Ramos GS, Kreis W, Braga FC, Alves RJ, de Pádua RM, and Simões CMO
- Subjects
- Acyclovir pharmacology, Animals, Antiviral Agents chemical synthesis, Cardenolides chemical synthesis, Chlorocebus aethiops, Drug Evaluation, Preclinical, Drug Resistance, Viral, Herpesviridae Infections drug therapy, Humans, Vero Cells, Antiviral Agents pharmacology, Cardenolides pharmacology, Herpesvirus 1, Human drug effects, Herpesvirus 2, Human drug effects
- Abstract
Human herpesviruses are among the most prevalent pathogens worldwide and have become an important public health issue. Recurrent infections and the emergence of resistant viral strains reinforce the need of searching new drugs to treat herpes virus infections. Cardiac glycosides are used clinically to treat cardiovascular disturbances, such as congestive heart failure and atrial arrhythmias. In recent years, they have sparked new interest in their potential anti-herpes action. It has been previously reported by our research group that two new semisynthetic cardenolides, namely C10 (3β-[(N-(2-hydroxyethyl)aminoacetyl]amino-3-deoxydigitoxigenin) and C11 (3β-(hydroxyacetyl)amino-3-deoxydigitoxigenin), exhibited potential anti-HSV-1 and anti-HSV-2 with selectivity index values > 1,000, comparable with those of acyclovir. This work reports the mechanism investigation of anti-herpes action of these derivatives. The results demonstrated that C10 and C11 interfere with the intermediate and final steps of HSV replication, but not with the early stages, since they completely abolished the expression of the UL42 (β) and gD (γ) proteins and partially reduced that of ICP27 (α). Additionally, they were not virucidal and had no prophylactic effects. Both compounds inhibited HSV replication at nanomolar concentrations, but cardenolide C10 was more active than C11 and can be considered as an anti-herpes drug candidate including against acyclovir-resistant HSV-1 strains.
- Published
- 2020
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18. Investigation of the cytotoxic activity of two novel digitoxigenin analogues on H460 lung cancer cells.
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Boff L, Persich L, Brambila P, Ottoni FM, Munkert J, Ramos GS, Soares Viana AR, Kreis W, Braga FC, Alves RJ, Maia de Pádua R, Schneider NFZ, and Oliveira Simões CM
- Subjects
- Humans, Lung Neoplasms drug therapy, Tumor Cells, Cultured, Antineoplastic Agents pharmacology, Apoptosis, Cell Proliferation, Digitoxigenin analogs & derivatives, Digitoxigenin chemistry, Digitoxigenin pharmacology, Lung Neoplasms pathology
- Abstract
Cardiac glycosides (CGs) are natural compounds traditionally used for the treatment of heart disorders, and recently new therapeutic possibilities were proposed. Their antitumor reports and clinical trials have notably enhanced, including those targeted for lung cancer, the most lethal type that lacks of new treatment agents, instigating the research of these molecules. The CGs studied here, named C10 {3β-[(N-(2-hydroxyethyl)aminoacetyl]amino-3-deoxydigitoxigenin} and C18 (3β-(aminoacetyl)amino-3-deoxydigitoxigenin), are semisynthetic derivatives prepared from digitoxigenin scaffold. Both compounds demonstrated high cytotoxicity for different cancer cell lines, especially H460 lung cancer cells, and their cytotoxic effects were deeply investigated using different methodological approaches. C10 induced cell death at lower concentrations and during shorter periods of treatment than C18, and increased the number of small and irregular nuclei, which are characteristics of apoptosis. This type of cell death was confirmed by caspase-3/7 assay. Both compounds reduced H460 cells proliferative potential by long-term action, and C10 showed the strongest potential. Moreover, these compounds induced a significant decrease of the area and viability of H460 spheroids providing preclinical favorable profiles to develop new chemotherapeutic agents.
- Published
- 2020
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19. Potential anti-herpes and cytotoxic action of novel semisynthetic digitoxigenin-derivatives.
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Boff L, Munkert J, Ottoni FM, Zanchett Schneider NF, Ramos GS, Kreis W, Fernandes de Andrade S, Dias de Souza Filho J, Braga FC, Alves RJ, Maia de Pádua R, and Oliveira Simões CM
- Subjects
- Cell Death drug effects, Cell Line, Cell Line, Tumor, Click Chemistry, Digitoxigenin analogs & derivatives, Digitoxigenin chemical synthesis, Drug Screening Assays, Antitumor, Glycosides chemistry, Herpesvirus 1, Human drug effects, Herpesvirus 2, Human drug effects, Humans, Antineoplastic Agents chemistry, Antiviral Agents chemistry, Digitoxigenin pharmacology, Herpesviridae Infections drug therapy
- Abstract
In recent years, new therapeutic possibilities were proposed for cardiac glycosides traditionally used to treat heart diseases, such as anticancer and antiviral activities. In this sense, this work aimed to synthesize the readily accessible 3β-azido-3-deoxydigitoxigenin (5) from digitoxigenin (1). Two new series of compounds were obtained from derivative (5): (i) O-glycosyl trizols through click chemistry with propargyl glycosides; and (ii) compounds substituted in the alpha carbonyl position with different residues linked via an amino-group. All obtained derivatives have their chemical structures confirmed, and their anti-herpes (against HSV-types 1 and 2 replication) and cytotoxic (against PC3, A549, HCT-8 and LNCaP cell lines) activities evaluated. Compounds 10 and 11 exhibited the most promising results against HSV-1 (KOS and 29-R strains) and HSV-2 (333 strain) replication with SI values > 1000. Both compounds were also the most cytotoxic for the human cancer cell lines tested with IC
50 values similar to those of paclitaxel. They also presented reduced toxicity toward non-cancerous cell lines (MRC-5 and HGF cells). Promising compounds were tested in regard to their ability to inhibit Na+ /K+ -ATPase. The inhibition rate correlates suitably with the bioactivity demonstrated by those both compounds against the different human cancer cells tested as well as against HSV replication. Moreover, the results showed that specific chemical features of compound 10 and 11 influenced the bioactivities tested. In summary, it was possible to obtain novel digitoxigenin-derivatives with remarkable cytotoxic and anti-herpes activities as well as low toxicity and high selectivity. In this way, they could be considered potential molecules for the development of new drugs., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)- Published
- 2019
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20. Sublethal exposure to deltamethrin reduces the abilities of giant water bugs to prey upon Aedes aegypti larvae.
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Valbon WR, Cruz FM, Ramos GS, Tomé HVV, and Oliveira EE
- Subjects
- Aedes, Animals, Feeding Behavior drug effects, Larva, Mosquito Control, Heteroptera drug effects, Insecticides adverse effects, Nitriles pharmacology, Pyrethrins pharmacology
- Abstract
Freshwater ecosystems provide environmental conditions for many arthropod species, including pests like mosquitoes and beneficial insects. Giant water bugs, Belostoma anurum (Hemiptera: Belostomatidae), are aquatic insects that provide biological control of mosquitoes and small vertebrates in freshwater environments. However, the application of insecticides aiming to control mosquitoes can lead to insecticide exposures of aquatic predators that can result in their death or significant reductions in their behavioral abilities. Here, we assessed the susceptibilities of B. anurum to the pyrethroid insecticide deltamethrin and evaluated whether sublethal exposure to deltamethrin would change the abilities of B. anurum to prey upon larvae of Aedes aegypti (Diptera: Culicidae). Bioassays of predator performance were conducted at three prey densities (i.e., 3, 6 and 9 larvae/100 mL of water) just after insecticide exposure and on the three following days. Our results revealed that B. anurum (LC
50 = 90.9 μg a. i./L) was approximately 32-fold less susceptible to deltamethrin than A. aegypti larvae (LC50 = 2.8 μg a. i./L). However, the number of larvae eaten by B. anurum sublethally exposed to deltamethrin (at 13 μg a. i./L for 24 h) was significantly (P < 0.05) smaller than that recorded for unexposed predators. Furthermore, the deltamethrin-mediated behavioral changes were higher at the highest availability of prey and, as expected, just after insecticide exposure. Thus, sublethal exposure to deltamethrin reduces the ability of B. anurum to capture and prey upon A. aegypti larvae, compromising the efficacy of these insects as naturally occurring mosquito control agents., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2018
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21. Mixed Formulation of Conventional and Pegylated Meglumine Antimoniate-Containing Liposomes Reduces Inflammatory Process and Parasite Burden in Leishmania infantum-Infected BALB/c Mice.
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Reis LES, Fortes de Brito RC, Cardoso JMO, Mathias FAS, Aguiar Soares RDO, Carneiro CM, de Abreu Vieira PM, Ramos GS, Frézard FJG, Roatt BM, and Reis AB
- Subjects
- Animals, Drug Delivery Systems, Female, Inflammation prevention & control, Interferon-gamma immunology, Interleukin-10 biosynthesis, Leishmaniasis, Visceral parasitology, Liposomes therapeutic use, Meglumine chemistry, Meglumine Antimoniate, Mice, Mice, Inbred BALB C, Organometallic Compounds chemistry, Parasite Load, Polyethylene Glycols chemistry, Antiprotozoal Agents therapeutic use, CD4-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes immunology, Leishmania infantum drug effects, Leishmaniasis, Visceral drug therapy, Meglumine therapeutic use, Organometallic Compounds therapeutic use
- Abstract
Pentavalent antimonial has been the first choice treatment for visceral leishmaniasis; however, it has several side effects that leads to low adherence to treatment. Liposome-encapsulated meglumine antimoniate (MA) arises as an important strategy for chemotherapy enhancement. We evaluated the immunopathological changes using the mixture of conventional and pegylated liposomes with MA. The mice were infected with Leishmania infantum and a single-dose treatment regimen. Comparison was made with groups treated with saline, empty liposomes, free MA, and a liposomal formulation of MA (Lipo MA). Histopathological analyses demonstrated that animals treated with Lipo MA showed a significant decrease in the inflammatory process and the absence of granulomas. The in vitro stimulation of splenocytes showed a significant increase of gamma interferon (IFN-γ) produced by CD8
+ T cells and a decrease in interleukin-10 (IL-10) produced by CD4+ and CD8+ T cells in the Lipo MA. Furthermore, the Lipo MA group showed an increase in the IFN-γ/IL-10 ratio in both CD4+ and CD8+ T cell subsets. According to the parasite load evaluation using quantitative PCR, the Lipo MA group showed no L. infantum DNA in the spleen (0.0%) and 41.4% in the liver. In addition, we detected a low positive correlation between parasitism and histopathology findings (inflammatory process and granuloma formation). Thus, our results confirmed that Lipo MA is a promising antileishmanial formulation able to reduce the inflammatory response and induce a type 1 immune response, accompanied by a significant reduction of the parasite burden into hepatic and splenic compartments in treated animals., (Copyright © 2017 American Society for Microbiology.)- Published
- 2017
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22. Bt i -based insecticide enhances the predatory abilities of the backswimmer Buenoa tarsalis (Hemiptera: Notonectidae).
- Author
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Gutiérrez Y, Ramos GS, Tomé HVV, Oliveira EE, and Salaro AL
- Subjects
- Animals, Bacillus thuringiensis Toxins, Heteroptera physiology, Bacterial Proteins toxicity, Endotoxins toxicity, Hemolysin Proteins toxicity, Heteroptera drug effects, Insecticides toxicity, Predatory Behavior drug effects
- Abstract
The backswimmer Buenoa tarsalis (Hemiptera: Notonectidae) is a naturally occurring predator of immature stages of mosquitoes. These aquatic predators can suffer from non-targeted exposure to insecticides that are commonly used in aquatic environments to control mosquitoes. Here, we evaluated whether insecticide formulations containing the bacterium Bacillus thuringiensis var. israelensis (Bt
i ) or the organophosphate pirimiphos-methyl would affect the survival and the predatory abilities of B. tarsalis. First, we conducted survival bioassays to estimate the median survival time (LT50 ) of B. tarsalis when exposed to Bti -based insecticide (at 0.25 and 25 mg a.i./L) and pirimiphos-methyl (at 1, 10 and 1000 mg a.i./L). The highest concentrations of the insecticides were equivalent to the label-recommended field rates. Second, the predatory abilities of B. tarsalis exposed to insecticides were evaluated at three prey densities (3, 6 and 9 mosquito larvae/100 mL water) just after insecticide exposure or after a 24 h recovery time. While the survival of B. tarsalis was significantly reduced with pirimiphos-methyl concentrations ≥10 mg a.i./L, the Bti -exposed predators exhibited similar survival as unexposed predators. Interestingly, after a recovery time of 24 h, B. tarsalis sublethally exposed to pirimiphos-methyl or Bti -based insecticide consistently killed more A. aegypti larvae (at the intermediate density) than unexposed predators. However, for the without-recovery bioassays, the pirimiphos-methyl-exposed predators exhibited reduced predatory abilities at the lowest prey density. Because they do not reduce the survival or the predatory abilities of B. tarsalis, Bti -based insecticides can be considered a safe insecticide to use in the presence of backswimmers.- Published
- 2017
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23. Agrochemical synergism imposes higher risk to Neotropical bees than to honeybees.
- Author
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Tomé HV, Ramos GS, Araújo MF, Santana WC, Santos GR, Guedes RN, Maciel CD, Newland PL, and Oliveira EE
- Abstract
Bees are key pollinators whose population numbers are declining, in part, owing to the effects of different stressors such as insecticides and fungicides. We have analysed the susceptibility of the Africanized honeybee, Apis mellifera , and the stingless bee, Partamona helleri, to commercial formulations of the insecticides deltamethrin and imidacloprid. The toxicity of fungicides based on thiophanate-methyl and chlorothalonil were investigated individually and in combination, and with the insecticides. Results showed that stingless bees were more susceptible to insecticides than honeybees. The commercial fungicides thiophanate-methyl or chlorothalonil caused low mortality, regardless of concentration; however, their combination was as toxic as imidacloprid to both species, and over 400-fold more toxic than deltamethrin for A. mellifera . There were highly synergistic effects on mortality caused by interactions in the mixture of imidacloprid and the fungicides thiophanate-methyl, chlorothalonil and the combined fungicide formulation in A. mellifera, and also to a lesser extent in P. helleri . By contrast, mixtures of the deltamethrin and the combined fungicide formulation induced high synergy in P. helleri , but had little effect on the mortality of A. mellifera . Differences in physiology and modes of action of agrochemicals are discussed as key factors underlying the differences in susceptibility to agrochemicals.
- Published
- 2017
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24. Gadolinium(III) Complexes with N-Alkyl-N-methylglucamine Surfactants Incorporated into Liposomes as Potential MRI Contrast Agents.
- Author
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Silva SR, Duarte ÉC, Ramos GS, Kock FV, Andrade FD, Frézard F, Colnago LA, and Demicheli C
- Abstract
Complexes of gadolinium(III) with N-octanoyl-N-methylglucamine (L8) and N-decanoyl-N-methylglucamine (L10) with 1 : 2 stoichiometry were synthesized and characterized by elemental analysis, electrospray ionization-tandem mass spectrometry (ESI-MS), infrared (IR) spectroscopy, and molar conductivity measurements. The transverse (r 2) and longitudinal (r 1) relaxivity protons were measured at 20 MHz and compared with those of the commercial contrasts. These complexes were incorporated in liposomes, resulting in the increase of the vesicle zeta potential. Both the free and liposome-incorporated gadolinium complexes showed high relaxation effectiveness, compared to commercial contrast agent gadopentetate dimeglumine (Magnevist). The high relaxivity of these complexes was attributed to the molecular rotation that occurs more slowly, because of the elevated molecular weight and incorporation in liposomes. The results establish that these paramagnetic complexes are highly potent contrast agents, making them excellent candidates for various applications in molecular MR imaging.
- Published
- 2015
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25. Amphiphilic Antimony(V) Complexes for Oral Treatment of Visceral Leishmaniasis.
- Author
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Fernandes FR, Ferreira WA, Campos MA, Ramos GS, Kato KC, Almeida GG, Corrêa JD Junior, Melo MN, Demicheli C, and Frézard F
- Abstract
The need for daily parenteral administration is an important limitation in the clinical use of pentavalent antimonial drugs against leishmaniasis. In this study, amphiphilic antimony(V) complexes were prepared from alkylmethylglucamides (L8 and L10, with carbon chain lengths of 8 and 10, respectively), and their potential for the oral treatment of visceral leishmaniasis (VL) was evaluated. Complexes of Sb and ligand at 1:3 (SbL8 and SbL10) were obtained from the reaction of antimony(V) with L8 and L10, as evidenced by elemental and electrospray ionization-tandem mass spectrometry (ESI-MS) analyses. Fluorescence probing of hydrophobic environment and negative-staining transmission electron microscopy showed that SbL8 forms kinetically stabilized nanoassemblies in water. Pharmacokinetic studies with mice in which the compound was administered by the oral route at 200 mg of Sb/kg of body weight indicated that the SbL8 complex promoted greater and more sustained Sb levels in serum and liver than the levels obtained for the conventional antimonial drug meglumine antimoniate (Glucantime [Glu]). The efficacy of SbL8 and SbL10 administered by the oral route was evaluated in BALB/c mice infected with Leishmania infantum after a daily dose of 200 mg of Sb/kg for 20 days. Both complexes promoted significant reduction in the liver and spleen parasite burdens in relation to those in the saline-treated control group. The extent of parasite suppression (>99.96%) was similar to that achieved after Glu given intraperitoneally at 80 mg of Sb/kg/day. As expected, there was no significant reduction in the parasitic load in the group treated orally with Glu at 200 mg of Sb/(kg day). In conclusion, amphiphilic antimony(V) complexes emerge as an innovative and promising strategy for the oral treatment of VL., (Copyright © 2013, American Society for Microbiology. All Rights Reserved.)
- Published
- 2013
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26. Comparison of cognitive function between patients on chronic hemodialysis who carry out assisted physical activity and inactive ones.
- Author
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Martins CT, Ramos GS, Guaraldo SA, Uezima CB, Martins JP, and Ribeiro Junior E
- Subjects
- Adult, Female, Humans, Male, Middle Aged, Surveys and Questionnaires, Cognition physiology, Exercise Therapy, Motor Activity, Renal Dialysis
- Abstract
Physical inactivity is a determinant of clinical disorders and psychological problems in patients with chronic kidney disease patients. In two satellite clinics, a program of physical activity (PA) was offered to 86 patients undergoing hemodialysis. Of those, 49 patients entered the PA program spontaneously and 37 remained inactive. After six months, a satisfaction self-reported questionnaire and the Modified Mini-Mental State (3MS) Examination for assessment of cognitive function were applied. Cognition was compared between inactive patients and those participating in the PA program for at least three months. Regardless of age and duration of dialysis, patients showed a cognitive deficit greater than expected. In the general group, better cognitive function was observed in active patients as compared to the inactive ones (p < 0.05). When separated by age groups, active patients over the age of 60 years had better results than the inactive ones (p < 0.05). We concluded that patients with better cognitive responses are more physically active and/or physical activity contributes to better cognitive function.
- Published
- 2011
27. Clinical description of intracranial hemorrhage associated with bleeding disorders.
- Author
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González-Duarte A, García-Ramos GS, Valdés-Ferrer SI, and Cantú-Brito C
- Subjects
- Adolescent, Adult, Aged, Anemia, Aplastic classification, Anemia, Aplastic complications, Anemia, Aplastic epidemiology, Cerebral Hemorrhage blood, Cerebral Hemorrhage mortality, Cerebral Hemorrhage pathology, Female, Hemorrhagic Disorders blood, Hemorrhagic Disorders diagnosis, Hemorrhagic Disorders epidemiology, Hospital Mortality, Humans, Male, Middle Aged, Myelodysplastic Syndromes blood, Myelodysplastic Syndromes complications, Myelodysplastic Syndromes epidemiology, Neoplasms blood, Neoplasms complications, Neoplasms epidemiology, Purpura, Thrombocytopenic, Idiopathic blood, Purpura, Thrombocytopenic, Idiopathic complications, Purpura, Thrombocytopenic, Idiopathic epidemiology, Recurrence, Retrospective Studies, Risk Factors, Thrombocytopenia blood, Thrombocytopenia complications, Thrombocytopenia epidemiology, Treatment Outcome, Cerebral Hemorrhage etiology, Hemorrhagic Disorders complications
- Abstract
Background: Intracerebral hemorrhage (ICH) is an unusual but serious complication of bleeding disorders. ICH is believed to follow thrombocytopenia, alterations in coagulation, and vascular fragility. Information regarding its distribution is nonconclusive, and the mechanism of bleeding is not fully understood. The aim of this study was to examine the clinical and neuroimaging features of ICH in patients with bleeding disorders to predict risk factors for this condition., Methods: All cases of ICH diagnosed from 1987 to 2004 were retrospectively identified using the centralized database of our institution. Cases were included whenever ICH was caused by a primary hematologic disorder. The clinical characteristics, neuroimages, and outcome were analyzed., Results: A total of 31 patients were identified. ICH was the initial presentation of the bleeding disorder in 9 patients. Overall, 71% had systemic bleeding concurrent to the ICH. All patients had altered mental status. In 45.2% of the patients simultaneous intracranial hemorrhages were found. Eight patients had recurrent ICH. Severe thrombocytopenia (platelet count < 10,000/mm(3)) was present in 41% and very low platelets (=1000/mm(3)) in 3%. Death occurred in 71%., Conclusions: Multiple ICH is not an unusual presentation in patients with primary bleeding disorders developing brain hemorrhage. Although low platelet counts can be blamed for the bleeding, factors different from thrombocytopenia should be considered as the principal mechanism. The best predictor of cerebral bleeding is the presence of systemic bleeding.
- Published
- 2008
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28. Subarachnoid hemorrhage as a complication of systemic lupus erythematosus.
- Author
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Baizabal Carvallo JF, Cantú Brito C, Estañol B, and García Ramos GS
- Subjects
- Adult, Aged, Cerebral Angiography, Chronic Disease, Databases as Topic, Female, Humans, Lupus Erythematosus, Systemic epidemiology, Lupus Erythematosus, Systemic pathology, Lupus Erythematosus, Systemic therapy, Magnetic Resonance Angiography, Male, Middle Aged, Prevalence, Retrospective Studies, Risk Factors, Severity of Illness Index, Subarachnoid Hemorrhage epidemiology, Subarachnoid Hemorrhage pathology, Subarachnoid Hemorrhage therapy, Tomography, X-Ray Computed, Treatment Outcome, Lupus Erythematosus, Systemic complications, Subarachnoid Hemorrhage etiology
- Abstract
Background: Subarachnoid hemorrhage (SAH) is a rare complication of systemic lupus erythematosus (SLE)., Methods: We made a retrospective search for patients with SLE and nontraumatic SAH from 1990 to 2006., Results: We found 10 patients with SLE and primary SAH of a total of 1,077 patients with SLE (0.93%); mean age of onset was 37.4 +/- 15.25 years and the mean duration of SLE at the onset of SAH was 98.3 +/- 50.32 months. SLEDAI and chronic damage scores were 3.67 +/- 5.20 (n = 9) and 2.90 +/- 1.45 (n = 10), respectively; 60% of patients had high Hunt-Hess scores and in only 50% of cases a saccular aneurysm was identified., Conclusions: SAH presents in about 1% of SLE patients. Long duration of SLE and chronic damage scores might be associated risk factors.
- Published
- 2007
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29. [Isolation and characterization of immune complexes associated with malignant tumors and leprosy].
- Author
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Segal-Eiras A, Croce MV, Ramos GS, and Córsico B
- Subjects
- Adolescent, Adult, Aged, Child, Child, Preschool, Electrophoresis, Polyacrylamide Gel, Female, Humans, Male, Middle Aged, Antigen-Antibody Complex isolation & purification, Leprosy immunology, Neoplasms immunology
- Abstract
We are dedicated to the study of circulating immune complexes (CIC) associated with different diseases: malignant tumors, leprosy and rheumatoid arthritis. Immune complexes were evaluated by various methods: 125I-Clq binding assay, 125I-IgG binding test, 125I-bovine conglutinin binding assay and polyethylene glycol precipitation test (3.5% and 2.5%). Techniques for the isolation and splitting of CIC in their components were performed in sera from patients with tumors and with leprosy. These methods consisted in the combination of CIC with protein A followed by elution with different buffers. CIC splitting techniques were first applied on immune complexes formed in vitro (BSA-aBSA, OVA-aOVA). The analysis of CIC fractions was done by SDS-PAGE, immunoelectrophoresis and immunoblotting techniques. Results were as follows: CIC levels correlated with active stages of disease, decreasing during remission so that CIC detection can be useful to evaluate response to treatment. The isolation and splitting of immune complexes into their components resulted in the obtention of immunologically active fractions, especially in sera from patients with gastrointestinal and breast cancer and with leprosy.
- Published
- 1989
30. Evaluation of circulating immune complexes in leprosy.
- Author
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Ramos GS, Bottasso OA, Morini JC, and Segal-Eiras A
- Subjects
- Antigen-Antibody Complex immunology, Humans, Leprosy, Lepromatous immunology, Leprosy, Tuberculoid immunology, Antigen-Antibody Complex analysis, Leprosy, Lepromatous blood, Leprosy, Tuberculoid blood
- Abstract
Circulating immune complexes (CIC) were evaluated in leprosy by 4 methods: the 125I-C1q binding assay (C1q), the platelet aggregation test (PAT), the 3.5% polyethylene glycol (PEG) precipitation test and the 2.5% PEG precipitation assay. Serum samples belonged to lepromatous leprosy bacilloscopy positive (LL+), lepromatous leprosy bacilloscopy negative (LL-), tuberculoid (TT) and first grade contact group (Co). Studies performed by the 3 first methods showed higher CIC levels in LL+ group (p less than 0.01) and lower values in the 3 others, all of them when compared to normals. On the contrary, the 2.5% PEG precipitation test gave less discriminative results giving only p less than 0.01 in LL+. CIC values obtained in the contact group showed significant results compared to normals but similar to LL- and TT groups. The C1q binding assay and the PAT were the most discriminative methods giving r = 0.90; C1q versus 3.5% PEG, r = 0.36; C1q vs 2.5% PEG, r = 0.14. The PAT compared to 3.5% PEG, r = 0.48 and PAT vs. 2.5% PEG, r = 0.24. Therefore it may be concluded as follows: a) The radioiodinated C1q binding assay and the PAT are recommended for the study of CIC in leprosy; b) The 2.5% PEG precipitation assay offers less sensitivity since it gave similar value in LL-, TT, Co and controls; c) CIC levels observed in LL+ patients may be induced by the antigenic overload demonstrated by the positive bacilloscopy; d) The contacts have CIC levels significantly different from the normal population possibly caused by a subclinical infection.
- Published
- 1988
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