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1.
Poult Sci ; 103(5): 103567, 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38417302

RESUMO

Improving productive performance is a daily challenge in the poultry industry. Developing cost-effective additives and strategies that improve performance in antibiotic-free poultry production is critical to maintaining productivity and efficiency. This study evaluates the influence of a commercially available phytogenic feed additive (CA-PFA, that comprises silymarin, betaine and curcumin extracts as main ingredients) and silymarin on commercial broilers' productive performance and liver function with and without carbon tetrachloride (CCl4)-induced liver damage. The experiment was conducted in a completely randomized design, with six treatments, eight replicates, and eight birds per replicate in 18 one-day-old male broilers (Cobb Vantress 500) each; under a 3 × 2 factorial arrangement (3 diets x 2 levels of CCl4, 0 and 1 mL/kg body weight orally). The experimental treatments included 3 diets, commercially recommended doses of CA-PFA (500 mg/kg of feed; this dose provides 70 mg/kg of silymarin, besides the other active ingredients included in the formulation), silymarin (250 mg/kg of feed, containing 28% of active ingredient; this dose provides 70 mg/kg of silymarin as active ingredient) and an additive-free basal diet as a control. A standard commercial silymarin was used as a reference due to its well-known and extensively studied hepatoprotective properties that can mitigate the negative effects of CCl4 in the liver. The data were analyzed as a 2-way ANOVA, and the means showing significant (P ≤ 0.05) differences were then compared using the Post-Hoc Tukey HSD test. No interaction was detected between factors. Exposure to CCl4 had a noticeable detrimental effect on alertness, productive performance, and liver function of broilers without a significant increase in mortality. Including CA-PFA in the diet improved productive performance compared to the basal diet from day 21 to the end of the trial, on day 42. While no influence in feed intake was detected for any treatment, CA-PFA improved body weight gain (BWG) and feed conversion ratio (FCR) significantly (P < 0.05) from day 21 to the end of the trial in healthy and CCl4-exposed birds. The results show that CA-PFA supplementation improves performance parameters in broilers with and without CCl4-induced liver damage, when compared to a basal diet and the addition of a standard commercial silymarin product.

2.
Connect Tissue Res ; 64(1): 40-52, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35726900

RESUMO

INTRODUCTION: RANKL plays an important role in the differentiation and maturation process of preosteoclast cells. The osteoclast is a multinucleated cell that can have various sizes and a variable number of nuclei. However, there are no models that allow us to understand how successive cell fusions have a limit, or how cell fusion is regulated. METHODOLOGY: The present investigation was aimed to determine whether fusing U937 cells with PEG to generate osteoclast-like cells expresses LGR4 and whether applying RANKL to these cells modifies osteoclastic activity compared to non-PEG-fused and RANKL-treated cells. RESULTS: By fusing U937 cells with PEG, it was found that the LGR4 receptor expression was promoted as early as 24 hours of culture. Applying RANKL before or after fusion inhibits osteoclastic activity. Interfering RANKL interaction with LGR4 in PEG-treated cells recovers and increases cell fusion and osteoclastic activity. PEG-fused U937 cells show osteoclast markers similar to those observed in the classical RANKL-stimulated cell model. CONCLUSION: Our model allows us to understand that RANKL has fusogenic activity during the first days of culture and in fused cells modulates fusion, contributing to differentiate the role of RANKL before and after fusion through LGR4.


Assuntos
Reabsorção Óssea , Osteogênese , Humanos , Reabsorção Óssea/metabolismo , Células U937 , Osteoclastos/metabolismo , Diferenciação Celular , Ligante RANK , Receptores Acoplados a Proteínas G/metabolismo
3.
Pathogens ; 13(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38251325

RESUMO

Acute diarrheal disease (ADD) caused by rotavirus (RV) contributes significantly to morbidity and mortality in children under five years of age. Currently, there are no specific drugs for the treatment of RV infections. Previously, we reported the anti-rotaviral activity of the protein metabolites derived from Bifidobacterium adolescentis. In this study, our aim was to assess the impact of B. adolescentis-secreted proteins (BaSP), with anti-rotaviral activity on the human intestinal C2BBe1 cell line. We initiated the production of BaSP and subsequently confirmed its anti-rotaviral activity by counting the infectious foci using immunocytochemistry. We then exposed the C2BBe1 cells to various concentrations of BaSP (≤250 µg/mL) for 72 h. Cell viability was assessed using the MTT assay, cell monolayer integrity was monitored through transepithelial electrical resistance (TEER), and cytoskeleton architecture and tight junctions (TJs) were examined using confocal microscopy with F-actin and occludin staining. Finally, we utilized a commercial kit to detect markers of apoptosis and necrosis after 24 h of treatment. The results demonstrated that BaSP does not have adverse effects on C2BBe1 cells. These findings confirm that BaSP inhibits rotavirus infectivity and has the potential to strengthen intestinal defense against viral and bacterial infections via the paracellular route.

4.
Acta Virol ; 66(1): 39-54, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35380864

RESUMO

Cells infected with MA104 rotavirus and/or transfected with plasmids expressing NSP proteins, were analyzed for expression of cellular proteins related to NFκB and PPARγ pathways and evaluated through the ELISA, luminescence, flow cytometry and Western blot techniques. The association between cellular and viral (NSPs) proteins was examined by ELISA, epifluorescence and confocal microscopy techniques. It was observed that NSP1 protein interacts with RXR, NSP1, and NSP3 with PPARγ, NSP2 with p-IKKα/ß and NSP5 with NFκB proteins. We have found that phosphorylated PPARγ is localized in cytoplasm and transcriptional activity of PPRE is diminished. These results lead to the conclusion, that RRV activates the proinflammatory pathway, increasing the expression of NFκB and possibly by PPARγ phosphorylation, its translocation to the nucleus is impeded, thus inactivating the proinflammatory pathway. Keywords: rotavirus; PPARγ; NFκB; NSPs; RRV.


Assuntos
NF-kappa B , PPAR gama , Infecções por Rotavirus , Proteínas não Estruturais Virais , Humanos , Imunidade , NF-kappa B/imunologia , PPAR gama/imunologia , Rotavirus/fisiologia , Infecções por Rotavirus/imunologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
5.
Educ Inf Technol (Dordr) ; 27(5): 7205-7239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35153537

RESUMO

This study describes the most relevant problems and solutions found in the literature on teaching and learning of object-oriented programming (OOP). The identification of the problem was based on tertiary studies from the IEEE Xplore, Scopus, ACM Digital Library and Science Direct repositories. The problems and solutions identified were ranked through the multi-criteria decision methods DEMATEL and TOPSIS in order to determine the best solutions to the problems found and to apply these results in the academic context. The main contribution of this study was the categorization of OOP problems and solutions, as well as the proposal of strategies to improve the problem. Among the most relevant problems it was found: 1) difficulty in understanding, teaching and implementing object-orientation, 2) difficulties related to understanding classes and 3) difficulty in understanding object-oriented relationships. After doing the multicriteria analysis, it was found that the most important solutions to face the problems found in the teaching of OOP were: 1) use of active learning techniques and intrinsic rewards and 2) emphasize on basic programming concepts and introduce the object-oriented paradigm at an early point in the curriculum. As a conclusion, it was evidenced that there is coherence between the literary guarantee that gives support to the problems and solutions in the teaching of OOP presented in this study and the approaches that experts in the area of development highlight as relevant when they identify weaknesses in the process.

6.
J Org Chem ; 86(15): 10903-10913, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34286987

RESUMO

The use of sodium dithionite with perfluoroalkyl iodides under basic conditions facilitates the direct perfluoroalkylation of arenes with pendant benzylic electron-withdrawing groups. This occurs via attack of the arene on the electrophilic perfluoroalkyl radical, through the donation of electron density from a benzylic anion. The substrate scope was expanded beyond benzylic nitriles with cyclic substrates bearing electron-withdrawing groups at the benzylic position-enforcing donation of electron density to the aromatic ring and enabling attack on the perfluoroalkyl radical.


Assuntos
Iodetos , Nitrilas , Elétrons , Estrutura Molecular
7.
Biomedica ; 40(2): 362-381, 2020 06 15.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32673463

RESUMO

INTRODUCTION: Cancer is the second leading cause of death in the United States, surpassed only by cardiovascular disease. However, cancer has now overtaken cardiovascular disease as the main cause of death in 12 countries in Western Europe. The burden of cancer is posing a major challenge to health care systems worldwide and demanding improvements in methods for cancer prevention, diagnosis, and treatment. Alternative and complementary strategies for orthodox surgery, radiotherapy, and chemotherapy need to be developed. OBJECTIVE: To determine the oncolytic potential of tumor cell-adapted rotavirus in terms of their ability to infect and lysate murine myeloma Sp2/0-Ag14 cells. MATERIALS AND METHODS: We inoculated rotaviruses Wt1-5, WWM, TRUYO, ECwt-O, and WTEW in Sp2/0-Ag14 cells and we examined their infectious effects by immunocytochemistry, immunofluorescence, flow cytometry, and DNA fragmentation assays. RESULTS: Rotavirus infection involved the participation of some heat shock proteins, of protein disulfide isomerase (PDI), and integrin ß3. We detected the accumulation of viral antigens within the virus-inoculated cells and in the culture medium in all the rotavirus isolates examined. The rotavirus-induced cell death mechanism in Sp2/0-Ag14 cells involved changes in cell membrane permeability, chromatin condensation, and DNA fragmentation, which were compatible with cytotoxicity and apoptosis. CONCLUSIONS: The ability of the rotavirus isolates Wt1-5, WWM, TRUYO, ECwt-O, and WTEW to infect and cause cell death of Sp2/0-Ag14 cells through mechanisms that are compatible with virus-induced apoptosis makes them potential candidates as oncolytic agents.


Introducción. El cáncer es la segunda causa de muerte en los Estados Unidos, solamente superado por la enfermedad cardiovascular. Sin embargo, el cáncer aventaja a la enfermedad cardiovascular como primera causa de muerte en doce países de Europa occidental. Se requieren mejores métodos de prevención, diagnóstico y tratamiento para afrontar el gran desafío que el cáncer representa mundialmente para los sistemas de salud, y se necesita desarrollar estrategias alternativas y complementarias a la cirugía, la radioterapia y la quimioterapia convencionales. Objetivo. Evaluar el potencial oncolítico de rotavirus adaptados a células tumorales por su capacidad para infectar y lisar células Sp2/0-Ag14 de mieloma de ratón. Materiales and métodos. Los aislamientos de rotavirus Wt1-5, WWM, TRUYO, ECwt-O y WTEW se inocularon en células Sp2/0-Ag14 y se examinaron sus efectos infecciosos mediante inmunocitoquímica, inmunofluorescencia, citometría de flujo y ensayos de fragmentación del ADN. Resultados. La infección con los rotavirus Wt1-5, WWM, TRUYO, ECwt-O y WTEW implicó la participación de algunas proteínas de choque térmico, la proteína disulfuro isomerasa y la integrina ß3. La acumulación de antígenos virales intracelulares y extracelulares se detectó en todos los virus utilizados. Los mecanismos de muerte inducidos por los rotavirus en células Sp2/0-Ag14 indujeron cambios en la permeabilidad de la membrana celular, la condensación de cromatina y la fragmentación de ADN, los cuales fueron compatibles con citotoxicidad y apoptosis. Conclusiones. La capacidad de los rotavirus estudiados para infectar y causar la muerte de células Sp2/0-Ag14 mediante mecanismos compatibles con la apoptosis inducida viralmente los convierte en candidatos potenciales para ser utilizados como agentes oncolíticos.


Assuntos
Efeito Citopatogênico Viral , Mieloma Múltiplo/terapia , Terapia Viral Oncolítica , Rotavirus , Sequência de Aminoácidos , Animais , Antígenos Virais/análise , Apoptose , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Cromatina/ultraestrutura , Meios de Cultura/química , Fragmentação do DNA , Proteínas de Choque Térmico/fisiologia , Integrina beta3/fisiologia , Camundongos , Mieloma Múltiplo/patologia , Isomerases de Dissulfetos de Proteínas/fisiologia , Rotavirus/imunologia , Rotavirus/fisiologia , Replicação Viral
8.
Org Lett ; 21(22): 9198-9202, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31647672

RESUMO

This communication highlights the use of chiral sulfinamides as nitrogen nucleophiles in intermolecular aza-Michael reactions. When chiral sulfinamides are coupled to a chloroethyl group, the corresponding novel annulating reagents can be used to streamline the stereoselective synthesis of complex pyrrolidine-containing molecules. As a result, it has enabled a medicinal chemistry campaign for the synthesis of biologically active RORγt inverse agonists.

9.
J Org Chem ; 82(19): 10715-10721, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28809492

RESUMO

An addition of organozinc nucleophiles to N-acyl activated quinolines and isoquinolines is described. Simple transmetalation with the corresponding Grignard reagents using ZnCl2 forms organozinc compounds which are functional group tolerant and stable to reactive acyl chloride reagents for extended periods. A wide variety of substrates which include reactive electron-withdrawing groups are well tolerated to form 2-substituted dihydroquinolines and dihydroisoquinolines. This methodology has been applied toward an improved synthetic route of uncialamycin and its analogs.

10.
J Am Chem Soc ; 139(20): 6819-6822, 2017 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-28463562

RESUMO

Herein we describe concise enantioselective chemical syntheses of (-)-viridin and (-)-viridiol. Our convergent approach couples two achiral fragments of similar complexity and employs an enantioselective intramolecular Heck reaction to set the absolute stereochemical configuration of an all-carbon quaternary stereocenter. To complete the syntheses of these base- and nucleophile-sensitive natural products, we conduct carefully orchestrated site- and diastereoselective oxidations and other transformations. Our work is the first to generate these targets as single enantiomers.


Assuntos
Androstenodióis/síntese química , Androstenos/síntese química , Bacteriocinas/síntese química , Androstenodióis/química , Androstenos/química , Bacteriocinas/química , Estrutura Molecular , Estereoisomerismo
11.
J Mol Histol ; 48(3): 169-185, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28343338

RESUMO

Bone is a metabolically active organ subjected to continuous remodeling process that involves resorption by osteoclast and subsequent formation by osteoblasts. Osteoclast involvement in this physiological event is regulated by macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor κB ligand (RANKL). Fusion of mono-nuclear pre-osteoclasts is a critical event for osteoclast differentiation and for bone resorption. Here we show that PBMCs can be successfully fused with polyethylenglicol (PEG) in order to generated viable osteoclast-like cells that exhibit tartrate-resistant acid phosphatase (TRAP) and bone resorptive activities. PEG-fused PBMCs expressed additional markers compatible with osteoclastogenic differentiation such as carbonic anhydrase II (CAII), calcitonin receptor (CR), cathepsin K (Cat K), vacuolar ATPase (V-ATPase) subunit C1 (V-ATPase), integrin ß3, RANK and cell surface aminopeptidase N/CD13. Actin redistribution in PEG-fused cells was found to be affected by cell cycle synchronization at G0/G1 or G2/M phases. PEG-induced fusion also led to expression of tyrosine kinases c-Src and Syk in their phosphorylated state. Scanning electron microscopy images showed morphological features typical of osteoclast-like cells. The results here shown allow concluding that PEG-induced fusion of PBMCs provides a suitable model system for understanding the mechanisms involved in osteoclastogenesis and for assaying new therapeutic strategies.


Assuntos
Diferenciação Celular , Fusão Celular , Leucócitos Mononucleares/metabolismo , Osteoclastos/citologia , Biomarcadores/análise , Biomarcadores/sangue , Reabsorção Óssea , Células Cultivadas , Humanos , Leucócitos Mononucleares/citologia , Modelos Biológicos , Polietilenoglicóis , Fosfatase Ácida Resistente a Tartarato/metabolismo
12.
J Bone Miner Metab ; 35(2): 127-141, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26969392

RESUMO

The bone remodeling process occurs through bone formation by osteoblasts and bone resorption by osteoclasts, a process involving the contribution of endocrine and nervous systems. The mechanisms associated to differentiation and proliferation of osteoclasts and osteoblasts are considered a potential therapeutic target for treating some erosive bone diseases. The aim of the present study is to explore the feasibility of generating active osteoclast-like cells from peripheral blood mononuclear cells (PBMCs) following polyethylene glycol (PEG)-induced fusion. PEG-fused PBMCs showed TRAP+-multinucleated cells and bone resorption activity, and were also positive for osteoclast markers such as carbonic anhydrase II, calcitonin receptor, vacuolar ATPase, and cathepsin K, when examined by reverse transcription-polymerase chain reaction, immunochemistry and Western blotting. TRAP expression and bone resorptive activity were higher in whole PEG-fused PBMCs than in separated T lymphocytes, B lymphocytes or monocytes. Both TRAP expression and bone resorptive activity were also higher in osteogenesis imperfecta patients compared to PEG-fused PBMCs from healthy individuals. PEG-induced fusion was more efficient in inducing TRAP and bone resorptive activities than macrophage colony-stimulating factor or dexamethasone treatment. Bone resorptive activity of PEG-fused PMBCs was inhibited by bisphosphonates. Evidence is provided that the use of PEG-based cell fusion is a straightforward and amenable method for studying human osteoclast differentiation and testing new therapeutic strategies.


Assuntos
Reabsorção Óssea/metabolismo , Leucócitos Mononucleares/citologia , Osteoclastos/citologia , Polietilenoglicóis/farmacologia , Adolescente , Linfócitos B/citologia , Linfócitos B/metabolismo , Técnicas de Cultura de Células , Fusão Celular , Células Cultivadas , Criança , Dexametasona/farmacologia , Difosfonatos/farmacologia , Humanos , Leucócitos Mononucleares/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Monócitos/citologia , Monócitos/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese Imperfeita/fisiopatologia , Linfócitos T/citologia , Linfócitos T/metabolismo , Fosfatase Ácida Resistente a Tartarato/metabolismo
13.
PPAR Res ; 2016: 4049373, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27382365

RESUMO

Rotavirus infection has been reported to induce an inflammatory response in the host cell accompanied by the increased expression or activation of some cellular molecules including ROS, NF-κB, and COX-2. PPARγ stimulation and N-acetylcysteine (NAC) treatment have been found to interfere with viral infections including rotavirus infection. Small intestinal villi isolated from in vivo infected mice with rotavirus ECwt were analyzed for the percentage of ECwt-infected cells, the presence of rotavirus antigens, and infectious virion yield following treatment with pioglitazone. Isolated villi were also infected in vitro and treated with PPARγ agonists (PGZ, TZD, RGZ, DHA, and ALA), all-trans retinoic acid (ATRA), and NAC. After treatments, the expression of cellular proteins including PPARγ, NF-κB, PDI, Hsc70, and COX-2 was analyzed using immunochemistry, ELISA, immunofluorescence, and Western blotting. The results showed that rotavirus infection led to an increased accumulation of the cellular proteins studied and ROS. The virus infection-induced accumulation of the cellular proteins studied and ROS was reduced upon pioglitazone treatment, causing also a concomitant reduction of the infectious virion yield. We hypothesized that rotavirus infection is benefiting from the induction of a host cell proinflammatory response and that the interference of the inflammatory pathways involved leads to decreased infection.

14.
World J Virol ; 5(2): 38-62, 2016 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-27175349

RESUMO

Rotaviruses are the single leading cause of life-threatening diarrhea affecting children under 5 years of age. Rotavirus entry into the host cell seems to occur by sequential interactions between virion proteins and various cell surface molecules. The entry mechanisms seem to involve the contribution of cellular molecules having binding, chaperoning and oxido-reducing activities. It appears to be that the receptor usage and tropism of rotaviruses is determined by the species, cell line and rotavirus strain. Rotaviruses have evolved functions which can antagonize the host innate immune response, whereas are able to induce endoplasmic reticulum (ER) stress, oxidative stress and inflammatory signaling. A networking between ER stress, inflammation and oxidative stress is suggested, in which release of calcium from the ER increases the generation of mitochondrial reactive oxygen species (ROS) leading to toxic accumulation of ROS within ER and mitochondria. Sustained ER stress potentially stimulates inflammatory response through unfolded protein response pathways. However, the detailed characterization of the molecular mechanisms underpinning these rotavirus-induced stressful conditions is still lacking. The signaling events triggered by host recognition of virus-associated molecular patterns offers an opportunity for the development of novel therapeutic strategies aimed at interfering with rotavirus infection. The use of N-acetylcysteine, non-steroidal anti-inflammatory drugs and PPARγ agonists to inhibit rotavirus infection opens a new way for treating the rotavirus-induced diarrhea and complementing vaccines.

15.
PLoS One ; 11(2): e0147666, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26828934

RESUMO

A number of viruses show a naturally extended tropism for tumor cells whereas other viruses have been genetically modified or adapted to infect tumor cells. Oncolytic viruses have become a promising tool for treating some cancers by inducing cell lysis or immune response to tumor cells. In the present work, rotavirus strains TRF-41 (G5) (porcine), RRV (G3) (simian), UK (G6-P5) (bovine), Ym (G11-P9) (porcine), ECwt (murine), Wa (G1-P8), Wi61 (G9) and M69 (G8) (human), and five wild-type human rotavirus isolates were passaged multiple times in different human tumor cell lines and then combined in five different ways before additional multiple passages in tumor cell lines. Cell death caused by the tumor cell-adapted isolates was characterized using Hoechst, propidium iodide, 7-AAD, Annexin V, TUNEL, and anti-poly-(ADP ribose) polymerase (PARP) and -phospho-histone H2A.X antibodies. Multiple passages of the combined rotaviruses in tumor cell lines led to a successful infection of these cells, suggesting a gain-of-function by the acquisition of greater infectious capacity as compared with that of the parental rotaviruses. The electropherotype profiles suggest that unique tumor cell-adapted isolates were derived from reassortment of parental rotaviruses. Infection produced by such rotavirus isolates induced chromatin modifications compatible with apoptotic cell death.


Assuntos
Adaptação Fisiológica , Rotavirus/fisiologia , Antígenos Virais/imunologia , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Sobrevivência Celular , Efeito Citopatogênico Viral , Quebras de DNA de Cadeia Dupla , Fragmentação do DNA , Reparo do DNA , Eletroforese em Gel de Ágar , Histonas/metabolismo , Humanos , Rotavirus/imunologia , Rotavirus/isolamento & purificação , Rotavirus/patogenicidade , Infecções por Rotavirus/virologia , Fatores de Tempo , Vírion/patogenicidade
16.
Rev. colomb. biotecnol ; 18(1): 33-48, ene.-jun. 2016. ilus
Artigo em Inglês | LILACS | ID: lil-791230

RESUMO

Introduction. Rotavirus entry into cells seems to be mediated by sequential interactions between viral structural proteins and some cell surface molecules. However, the mechanisms by which rotavirus infects target cell are still not well understood. There is some evidence showing that rotavirus structural proteins VP5* and VP8* interact with some cell surface molecules. The availability of recombinant rotavirus structural proteins in sufficient quantity has become very important for the identification of the specific virus-cell receptor interactions during the early events of the infectious process. Objective. The aim of the present work is to perform an analysis of the interactions between recombinant rotavirus structural proteins VP5*, VP8* and VP6, and cellular proteins Hsc70 and PDI using their purified recombinant versions. Materials and methods. Rotavirus recombinant VP5* and VP8*, and cellular recombinant proteins Hsc70 and PDI were expressed in E. coli BL21(DE3) while VP6 was expressed in recombinant vaccinia virus-transfected MA104 cells. The interaction between rotavirus and cellular proteins was studied using ELISA, co-immunoprecipitation and SDS-PAGE/Western blotting analysis. Results. The optimal conditions for expression of recombinant proteins were determined and antibodies were raised against them. The findings suggested that viral proteins rVP5* and rVP6 interact with Hsc70 and PDI in vitro. These viral recombinant proteins were also found to interact with raft-associated Hsc70 in a cell culture system. The treatment of cells with either rVP6 or DLPs produced significantly inhibition of rotavirus infection. Conclusion. The results allow us to conclude that rVP5* and rVP6 interact with Hsc70 and PDI during the rotavirus infection process.


Introducción. La entrada de rotavirus a las células parece estar mediado por interacciones secuenciales entre las proteínas estructurales virales y algunas moléculas de la superficie celular. Sin embargo, los mecanismos por los cuales el rotavirus infecta la célula diana aún no se comprenden bien. Existe alguna evidencia que muestra que las proteínas estructurales de rotavirus VP5* y VP8* interactúan con algunas moléculas de la superficie celular. La disponibilidad de las proteínas estructurales de rotavirus recombinantes en cantidad suficiente se ha convertido en un aspecto importante para la identificación de las interacciones específicas de los receptores virus-célula durante los eventos tempranos del proceso infeccioso. Objetivo. El propósito del presente trabajo es realizar un análisis de las interacciones entre las proteínas estructurales de rotavirus recombinante VP5*, VP8* y VP6, y las proteínas celulares Hsc70 y PDI utilizando sus versiones recombinantes purificadas. Materiales y métodos. Las proteínas recombinantes de rotavirus VP5* y VP8* y las proteínas recombinantes celulares Hsc70 y PDI se expresaron en E. coli BL21 (DE3), mientras que VP6 se expresó en células MA104 con virus vaccinia recombinante transfectada. La interacción entre el rotavirus y las proteínas celulares se estudió mediante ELISA, co-inmunoprecipitación y SDS-PAGE/ Western. Resultados. Las condiciones óptimas para la expresión de proteínas recombinantes se determinaron y se generaron anticuerpos contra ellas. Los resultados sugirieron que las proteínas virales rVP5* y rVP6 interactúan con Hsc70 y PDI in vitro. También se encontró que éstas proteínas virales recombinantes interactúan con Hsc70 en las balsas lipídicas ("Rafts") en un cultivo celular. El tratamiento de las células, ya sea con DLP o rVP6 produjo significativamente la inhibición de la infección por rotavirus. Conclusión. Los resultados permiten concluir que rVP5 * y rVP6 interactúan con Hsc70 y PDI durante el proceso de la infección por rotavirus.

17.
J Org Chem ; 80(4): 2397-406, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25648434

RESUMO

The mulinane class of diterpenoids is a set of tricyclic (5-6-7), biologically active natural products whose members exhibit a variety of oxidation states. Herein, we report the inaugural synthesis of four mulinanes employing a divergent approach that relies on a diastereoselective anionic oxy-Cope rearrangement to set the relative configuration of the C8 stereocenter and an unprecedented vinylogous Saegusa dehydrogenation reaction to address C-ring functionality.


Assuntos
Diterpenos/síntese química , Diterpenos/química , Conformação Molecular , Estereoisomerismo
18.
Pharmacotherapy ; 34(11): e333-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25251886

RESUMO

Rotaviruses are the leading cause of severe, acute, and dehydrating diarrhea affecting children under 5 years of age worldwide. Despite an important reduction in rotavirus-caused deaths as a consequence of the rotavirus vaccine, alternative or complementary strategies for preventing or treating rotavirus-associated diarrhea are needed mainly in the poorest countries. We describe the cases of four rotavirus-unvaccinated 12-13-month-old girls and a 5-year-old boy who developed rotavirus-associated diarrhea confirmed by enzyme-linked immunosorbent assay, Western blotting, and immunochemistry analyses. After the first day of diarrheal episodes, three of the five patients were immediately administered oral N-acetylcysteine (NAC) 60 mg/kg daily, divided into three equal doses every 8 hours. The other two patients did not receive NAC and served as controls. Administration of NAC resulted in a decreased number of diarrheal episodes, excretion of fecal rotavirus antigen, and resolution of symptoms after 2 days of treatment. Our results suggest that NAC treatment after the first diarrheal episode could be an efficient strategy for treating rotavirus-affected children and preventing the associated severe life-threatening accompanying dehydration.


Assuntos
Acetilcisteína/uso terapêutico , Antivirais/uso terapêutico , Diarreia Infantil/prevenção & controle , Diarreia/prevenção & controle , Gastroenterite/tratamento farmacológico , Infecções por Rotavirus/tratamento farmacológico , Acetilcisteína/administração & dosagem , Administração Oral , Antivirais/administração & dosagem , Pré-Escolar , Colômbia , Desidratação/etiologia , Desidratação/prevenção & controle , Diarreia/etiologia , Diarreia/fisiopatologia , Diarreia Infantil/etiologia , Diarreia Infantil/fisiopatologia , Feminino , Gastroenterite/fisiopatologia , Gastroenterite/virologia , Humanos , Lactente , Masculino , Recidiva , Infecções por Rotavirus/fisiopatologia , Infecções por Rotavirus/virologia , Índice de Gravidade de Doença , Resultado do Tratamento
19.
J Bacteriol ; 196(9): 1683-93, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24532776

RESUMO

In microbiology, gene disruption and subsequent experiments often center on phenotypic changes caused by one class of specialized metabolites (quorum sensors, virulence factors, or natural products), disregarding global downstream metabolic effects. With the recent development of mass spectrometry-based methods and technologies for microbial metabolomics investigations, it is now possible to visualize global production of diverse classes of microbial specialized metabolites simultaneously. Using imaging mass spectrometry (IMS) applied to the analysis of microbiology experiments, we can observe the effects of mutations, knockouts, insertions, and complementation on the interactive metabolome. In this study, a combination of IMS and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to visualize the impact on specialized metabolite production of a transposon insertion into a Pseudomonas aeruginosa phenazine biosynthetic gene, phzF2. The disruption of phenazine biosynthesis led to broad changes in specialized metabolite production, including loss of pyoverdine production. This shift in specialized metabolite production significantly alters the metabolic outcome of an interaction with Aspergillus fumigatus by influencing triacetylfusarinine production.


Assuntos
Proteínas de Bactérias/genética , Elementos de DNA Transponíveis , Mutagênese Insercional , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Proteínas de Bactérias/metabolismo , Cromatografia Líquida , Fenazinas/metabolismo , Pseudomonas aeruginosa/química , Espectrometria de Massas em Tandem
20.
J Am Chem Soc ; 135(33): 12188-91, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23855814

RESUMO

Herein, we describe a two-step method for the cyclopentannulation of conjugated enones using methyl 3-(tert-butyldimethylsilyloxy)-2-diazo-3-butenoate (1) as a bifunctional reagent. The enol silane and stabilized diazoalkane functionalities are exploited independently in sequential Mukaiyama-Michael and diastereoselective α,α'-diketone coupling. Di-, tri-, and tetrasubstituted enones are amenable to annulation under this protocol. Overall, this chemistry is an effective surrogate for a substituted "acetone 1,3-dipole".

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