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1H HR-MAS NMR and S180 cells: metabolite assignment and evaluation of pulse sequence
(2014-04) Oliveira, Aline Lima de; Martinelli, Bruno César Barbosa; Liao, Luciano Morais; Pereira, Flávia de Castro; Lacerda, Elisângela de Paula Silveira; Alcantara, Glaucia Braz
High resolution magic angle spinning 1H nuclear magnetic resonance spectroscopy (HR-MAS NMR) is a useful technique for evaluation of intact cells and tissues. However, optimal NMR parameters are crucial in obtaining reliable results. To identify the key steps for the optimization of HR-MAS NMR parameters, we assessed different pulse sequences and NMR parameters using sarcoma 180 (S180) cells. A complete assignment of the metabolites of S180 is given to assist future studies.
1H HRMAS NMR spectroscopy and chemometrics for evaluation of metabolic changes in citrus sinensis caused by xanthomonas axonopodis pv. citri
(2012-05) Silva, Lorena Mara Alexandre e; Alves Filho, Elenilson de Godoy; Choze, Rafael; Liao, Luciano Morais; Alcantara, Glaucia Braz
Xanthomonas axonopodis (Xac) bacterium causes one of the most feared and untreatable diseases in citriculture: citrus canker. To understand the response mechanisms of orange trees when attacked by Xac, leaves and fruits of Citrus sinensis were directly evaluated by HRMAS NMR (high resolution magic angle spinning nuclear magnetic resonance) spectroscopy. This technique allows the analysis of samples without laborious pre-treatments and also allows access to important information about chemical composition of samples. The orange tree leaves and fruit peels investigated in this study demonstrated the biochemical changes caused by Xac. Aided by chemometric analysis, the HRMAS NMR results show relevant changes in amino acids, carbohydrates, organic acids and terpenoids content.
2,5-diketopiperazines via intramolecular N-alkylation of Ugi adducts: a contribution to the synthesis, density functional theory study, X-ray characterization, and potential herbicide application
(2022) Mendes, Lorena Lessa; Varejão, Jodieh Oliveira Santana; Sousa, José Antonio de; Carneiro, José Walkimar de Mesquita; Valdo, Ana Karoline Silva Mendanha; Martins, Felipe Terra; Ferreira, Bruno Wesley; Barreto, Robert Weingart; Silva, Toshik Iarley da; Kohlhoff, Markus; Pilau, Eduardo Jorge; Varejão, Eduardo Vinícius Vieira
To investigate the herbicidal potential of 2,5-diketopiperazines (2,5-DKPs), we applied a known protocol to produce a series of 2,5-DKPs through intramolecular N-alkylation of Ugi adducts. However, the method was not successful for the cyclization of adducts presenting aromatic rings with some substituents at the ortho position. Results from DFT calculations showed that the presence of voluminous groups at the ortho position of a benzene ring results in destabilization of the transition structure. Lower activation enthalpies for the SN2-type cyclization of Ugi adducts were obtained when bromine, instead of a chlorine anion, is the leaving group, indicating that the activation enthalpy for the cyclization step controls the formation of the 2,5-DKP. Some Ugi adducts and 2,5-DKPs formed crystals with suitable qualities for single-crystal X-ray diffraction data collection. Phytotoxic damage of some 2,5-DKPs on leaves of the weed Euphorbia heterophylla did not differ from those caused by the commercial herbicide diquat.
2-(4-iodo-2,5-dimetoxifenil)-N-[(2-metoxifenil)metil]etamina ou 25I-NBOMe: caracterização química de uma designer drug
(2016) Santos, Pâmella Ferraz dos; Souza, Lindamara Maria de; Merlo, Bianca Bortolini; Costa, Helber Barcellos da; Tose, Lilian Valadares; Santos, Heloa; Costa, Gabriela Vanini; Machado, Leandro Fernandes; Ortiz, Rafael Scorsatto; Limberger, Renata Pereira; Vaz, Boniek Gontijo; Romão, Wanderson
Drug trafficking and the introduction of new drugs onto the illicit market are one of the main challenges of the forensic community. In this study, the chemical profile of a new designer drug, 2-(4-iodine-2,5- dimethoxyphenyl)-n-[(2-methoxyphenyl)methyl]etamine or 25I-NBOMe was explored using thin layer chromatography (TLC), ultraviolet-visible spectrophotometry (UV-Vis), attenuated total reflection with Fourier transform infrared spectroscopy(ATRFTIR), gas chromatography mass spectrometry (GC-MS) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR MS). First, the TLC technique was effective for identifying spots related to 25C-, 25B- and 25I-NBOMe compounds, all with the same retention factor, Rf ≈ 0.50. No spot was detected for 2,5-dimethoxy-4-bromoamphetamine, 2,5-Dimethoxy-4-chloroamphetamine or lysergic acid diethylamide compounds. ATR-FTIR preserved the physical-chemical properties of the material, whereas GC-MS and ESI-MS showed better analytical selectivity. ESI(+)FT-ICR MS was used to identify the exact mass (m/z 428.1706 for the [M + H]+ ion), molecular formula (M = C18H22INO3), degree of unsaturation (DBE = 8) and the chemical structure (from collision induced dissociation, CID, experiments) of the 25I-NBOMe compound. Furthermore, the ATR-FTIR and CID results suggested the presence of isomers, where a second structure is proposed as an isomer of the 25I-NBOMe molecule.
2D and 3D mixed MII/CuII metal–organic frameworks (M = Ca and Sr) with N,N′-2,6-pyridinebis(oxamate) and oxalate: preparation and magneto-structural study
(2018) Fernandes, Tamires Soares; Melo, Wanessa David Canedo; Kalinke, Lucas Hoffmann Greghi; Souza Filho, Renato Rabelo de; Valdo, Ana Karoline Silva Mendanha; Silva, Cameron Capeletti da; Martins, Felipe Terra; Amorós, Pedro; Lloret Pastor, Francesc; Julve Olcina, Miguel; Gomes, Danielle Cangussu de Castro
Three heterobimetallic complexes of formula [Ca2Cu3(mpyba)2(2-apyma)(H2O)7]·8.3H2O (1), [Sr2Cu3(mpyba)2(2-apyma)(H2O)8]·11.6H2O (2) and [Sr4.5Cu4(mpyba)4(ox)(H2O)20]·8.5H2O (3) [H4mpyba = N,N′-2,6-pyridinebis(oxamic acid), 2-apyma = 2-(6-aminopyridinyl)oxamate and ox = oxalate] have been synthesized and structurally characterized. Complexes 1 and 2 are isostructural compounds, with tricopper(II) units having mpyba and its hydrolytic product (2-apyma) as ligands. They are interlinked through strontium(II) (1) and calcium(II) (2) ions to afford neutral two-dimensional networks. Two of the copper(II) ions are five-coordinate in distorted square pyramidal (Cu3) and trigonal bipyramidal (Cu1) surroundings, whereas the other (Cu2) is six-coordinate in an elongated octahedral environment. The main difference between their structures, apart from the number of water molecules, resides in the nature of the alkaline earth cation coordinated to the oxamate fragments, Sr2+ (1)/Ca2+ (2), which exhibit eight and seven coordination, respectively. The π–π interactions and an extensive network of hydrogen bonds in 1 and 2 lead to supramolecular 3D structures. The relatively small size of their cavities, in the micropore domain, hinders the inclusion of N2 but allows CO2 adsorption (0.45 and 0.52 mmol g−1 for 1 and 2, respectively). The structure of 3 is made up of [3,3] metallacyclophane-type motifs, having the formula [Cu2(mpyba)2(H2O)2]4−. These act as tetrakis(bidentate) ligands towards the strontium(II) ions (Sr1, Sr2 and Sr3), leading to a sheet-like polymer growing in the bc plane, which extends further along the crystallographic a axis by a bis(chelating) oxalate between the Sr1 atoms. The investigation of the magnetic properties of 1–3 in the temperature range 1.9–300 K shows the occurrence of an overall antiferromagnetic behaviour for 1 and 2 [J12 = J23 = −9.71(2) (1) and −10.81(5) cm−1 (2), with the Hamiltonian being defined as H = −J12S1·S2 − J23S2·S3 + gβH[S1 + S2 + S3], and a ferromagnetic coupling within the dicopper(II) metallacylophane unit of 3 [J = +1.86(1) cm−1 through the Hamiltonian H = −JS1·S2 + gβH(S1 + S2)]. Simple orbital symmetry considerations (1–3) and the spin polarization mechanism (3) account for the observed magnetic properties.
3-phenacylideneoxindoles as a new class of antifungal compounds against Paracoccidioides spp
(2023-01-20) Silva, Lívia do Carmo; Santos Filho, Raimundo Francisco dos; Oliveira, Amanda Alves de; Martins, Felipe Terra; Cunha, Silvio do Desterro; Soares, Célia Maria de Almeida; Pereira, Maristela
Aims: Considering the need to identify new compounds with antifungal action, the activity of five 3-phenacylideneoxindoles compounds was evaluated. Materials & methods: The compounds were synthesized, and their antifungal activity was elucidated through minimum inhibitory concentration tests and interaction assay with other antifungals. Potential targets of compounds were predicted in silico. Results: 3-phenacylideneoxindoles compounds inhibited fungal growth with minimum inhibitory concentration and minimum fungicidal concentration ranging from 3.05 to 12.26 μM. The compounds demonstrated high selectivity index and presented a synergistic effect with itraconazole. In silico prediction revealed the pentafunctional AROM polypeptide, enolase, superoxide dismutase, catalase and kinases as proteins targets of the compound 4a. Conclusion: The results demonstrate that 3-phenacylideneoxindoles is a potential new class of antifungal compounds for paracoccidioidomycosis treatment.
3D printed microfluidic mixer for real-time monitoring of organic reactions by direct infusion mass spectrometry
(2022) Duarte, Lucas da Costa; Silva, Igor Pereira da; Maciel, Lanaia Ítala Louzeiro; Vaz, Boniek Gontijo; Coltro, Wendell Karlos Tomazelli
3D printing is a technology that has revolutionized traditional rapid prototyping methods due to its ability to build microscale structures with customized geometries in a simple, fast, and low-cost way. In this sense, this article describes the development of a microfluidic mixing device to monitor chemical reactions by mass spectrometry (MS). Microfluidic mixers were designed containing 3D serpentine and Y-shaped microchannels, both with a pointed end for facilitating the spray formation. The devices were fabricated entirely by 3D printing with fusion deposition modeling (FDM) technology. As proof-of-concept, micromixers were evaluated through monitoring the Katritzky reaction by injecting simultaneously 2,4,6-triphenylpropyllium (TPP) and amino acid (glycine or alanine) solutions, each through a different reactor inlet. Reaction product was monitored online by MS at different flow rates. Mass spectra showed that the relative abundances of the products obtained with the device containing the 3D serpentine channel were three times greater than those obtained with the Y-channel device due to the turbulence generated by the barriers created inside microchannels. In addition, when compared to the conventional electrospray ionization mass spectrometry (ESI-MS) technique, the 3D serpentine mixer offered better performance measured in relation to the relative abundance values for the reaction products. These results as well as the instrumental simplicity indicate that 3D printed microfluidic mixer is a promising tool for monitoring organic reactions via MS.
3D printing of microfluidic devices for paper-assisted direct spray ionization mass spectrometry
(2016) Duarte, Lucas da Costa; Carvalho, Thays Colletes de; Lobo Júnior, Eulício de Oliveira; Abdelnur, Patrícia Verardi; Vaz, Boniek Gontijo; Coltro, Wendell Karlos Tomazelli
This study describes the use of a 3D printer to fabricate microfluidic devices for direct spray ionization mass spectrometry (DS-MS) assisted by paper tips. The layout of the proposed devices was designed in a three-dimensional model through a computer-aided design system and printed by a fused deposition modeling method using a thermoplastic filament composed of acrylonitrile butadiene styrene deposited layer by layer. The smallest channel width was 400 μm to ensure 3D printing uniformity without any obstruction. For DS-MS studies, microfluidic channels consisted of a single channel connected to a sample reservoir (3 mm diameter). The printed channel was 3 cm long, 500 μm wide and 500 μm deep. Paper tips (0.5 cm long × ca. 0.5 mm wide) were manually cut and inserted into the extremity of the printed channel to facilitate the spray formation. The spray was promoted by the application of 4 kV at the sample reservoir containing 0.1% formic acid prepared in methanol. This organic medium selected for MS experiments has demonstrated great compatibility with the polymeric material employed to create microfluidic chips. 3D printed devices were kept at a distance of 3 mm from the MS entrance. Using glucose solution as the model, the formed spray by the proposed microfluidic device was extremely stable in comparison to traditional paper spray ionization devices for at least 10 min. The analytical feasibility of printed devices for DS-MS was successfully demonstrated by qualitative analysis of ballpoint pen inks, caffeine, xylose and lysozyme. The 3D printer has allowed the fabrication of printed devices at a very low cost ($0.05) within 20 min. Furthermore, 3D printed devices have exhibited significant repeatability and reproducibility, making their reuse possible. Based on the performance of the proposed devices, we believe they can be used in a broad range of bioanalytical applications.
4-Fluorobenzaldehyde limonene-based thiosemicarbazone induces apoptosis in PC-3 human prostate cancer cells
(2018) Rodrigues, Bruna dos Santos; Marcelino, Renato Ivan de Ávila; Miranda, Polyana Lopes Benfica; Pires, Ludmila Bringel; Oliveira, Cecilia Maria Alves de; Vandresen, Fábio; Silva, Cleuza Conceição da; Valadares, Marize Campos
Aims: This study evaluated parameters of toxicity and antiproliferative effects of (+)-N(1)-4-fluorobenzaldehyde-N(4)-{1-methyl-1-[(1R)-4-methylcyclohexene-3-il]-ethyl}-thiossemicarbazone (4-FTSC) in PC-3 adenocarcinoma prostate cells. Main methods: Cytotoxicity of 4-FTSC in PC-3 cells was evaluated using MTT assay. Morphology examination of PC-3 cells treated with 4-FTSC was also performed as well as the cell death mechanisms induced were investigated using flow cytometry. Parameters of toxicity of 4-FTSC was conducted by the investigation of its potential myelotoxicity and lymphotoxicity, hemolytic activity and acute oral toxicity profile. Key findings: 4-FTSC showed promising cytotoxic effects against PC-3 cells (IC50 = 18.46 μM). It also triggered apoptotic morphological changes, phosphatidylserine externalization and a significant increase of DNA fragmentation in PC-3 cells. Moreover, 4-FTSC did not show changes in the PC-3 cell cycle with levels of p21, p27, NFĸB and cyclin D1 similar to those found in both control and treated cells. 4-FTSC also promoted an increase of p53 levels associated with mitochondrial impairment through loss of ∆Ψm and ROS overproduction. 4-FTSC-induced cell death mechanism in PC-3 cells involved activation of caspase-3/-7 through apoptosis intrinsic pathway via caspase-9. Regarding toxicological profile, 4-FTSC showed in vitro lymphotoxicity, although with low cytotoxicity for bone marrow progenitors and no hemolytic potential. Moreover, it was classified as GHS category 5 (LD50 > 2000–5000 mg/Kg), suggesting it has low acute oral systemic toxicity. Significance: 4-FTSC seems to be a promising candidate to be used as a clinical tool in prostate cancer treatment. Further studies are required to better clarify its toxicopharmacological effects found in this compound.
A blue-light-emitting cadmium coordination polymer with 75.4% photoluminescence quantum yield
(2019) Nascimento Neto, José Antônio do; Valdo, Ana Karoline Silva Mendanha; Silva, Cameron Capeletti da; Guimarães, Freddy Fernandes; Queiroz Júnior, Luiz Henrique Keng; Maia, Lauro June Queiroz; Santana, Ricardo Costa de
We report a novel bright deep-blue-emitting crystal form based on a simple cadmium coordination polymer with an impressive external photoluminescence quantum yield of 75.4(9)%.
A comparative study on thermal behavior of solid-state light trivalent lanthanide isonicotinates in dynamic dry air and nitrogen atmospheres
(2016-02-24) Nunes, Wilhan Donizete Gonçalves; Teixeira, José Augusto; Nascimento, André Luiz Carneiro Soares do; Caires, Flávio Junior; Ionashiro, Elias Yuki; Ionashiro, Massao
Characterization, thermal stability, and thermal decomposition of light trivalent lanthanide isonicotinates Ln(L)32H2O (Ln = La to Gd, except Pm; L = isonicotinate) were investigated employing simultaneous thermogravimetry and differential scanning calorimetry (TG– DSC), DSC, infrared spectroscopy (FTIR), evolved gas analysis by TG–DSC coupled to FTIR, elemental analysis, and complexometry. The dehydration of these compounds occurs in a single step, and the thermal decomposition of the anhydrous compounds occurs in one or two (air) and two or three steps (N2). The final residues of thermal decomposition were CeO2, Pr6O11, and Ln2O3 (Ln = La, Nd to Gd) in air atmosphere, while in N2 atmosphere the mass loss is still being observed up to 1000 C. The results also provided information concerning the gaseous products evolved during the thermal decomposition in dynamic dry air and nitrogen atmospheres.
A metalloligand approach for the self-assembly of a magnetic two-dimensional grid-of-grids
(2019) Kalinke, Lucas Hoffmann Greghi; Gomes, Danielle Cangussu de Castro; Lloret Pastor, Francesc; Bruno, Rosaria; Armentano, Donatella; Pardo Marín, Emilio; Ferrando Soria, Jesús
The efficient organization of discrete functional molecules into extended frameworks, while retaining their physical properties, is a mandatory requisite to move toward applications. Here we describe the validity of the metalloligand design strategy as a versatile and powerful approach to build up a two-dimensional (2D) magnetic metal–organic framework (MOF) composed of preformed discrete antiferromagnetically coupled [3 × 3] Cu9II incomplete grids. In the first stage, a novel oxamato-based nonanuclear copper(II) complex has been self-assembled from the reaction of a polytopic organic ligand, with well-defined coordination pockets, with CuII ions. Then, the nonanuclear complex has been used as metalloligand toward calcium(II) cations to afford a CaII–CuII 2D MOF (1) with a grid-like topology and the magnetic properties of the preformed nonanuclear grids.
A new synthetic route and comprehensive topological study of a benzimidazole derivative
(2022) Silva, Vitor Santos; Naves, Raquel Ferreira; Bortoluzzi, Adailton João; Faria, Eduardo Coelho da Mata; Magalhães, Aline da Silva; Oliveira, Guilherme Roberto de; Alonso, Christian Gonçalves; Napolitano, Hamilton Barbosa
Benzimidazole and its derivatives are molecules that have diverse biological properties, therefore we synthesized and studied a new benzimidazole to understand their physical/chemical properties. The compound was obtained through a new synthetic route, using graphite oxide, in the absence of solvent, with crystalline packaging supported by C–H…N and C–H…π interactions. According to the frontier molecular orbitals, the compound is kinetically stable while the molecular electrostatic potential map confirms the site of molecular interactions involving nitrogen atoms and the π-system. This comprehensive study on synthesis, structural description and theoretical calculations can support ongoing studies in pharmaceutical science.
A novel water-soluble platinum(II) complex with the amino acid deoxyalliin: synthesis, crystal structure, theoretical studies and investigations about its antibacterial activity
(2021) Quintanilha, Mariana Mazzo; Schimitd, Bianca Alves; Costa, Adão Marcos Ferreira; Nakahata, Douglas Hideki; Simoni, Déborah de Alencar; Tenorio Clavijo, Juan Carlos; Pereira, Douglas Henrique; Massabni, Antonio Carlos; Lustri, Wilton Rogério; Corbi, Pedro Paulo
Platinum complexes have received special attention due to their biological properties with emphasis on the antitumor and antibacterial activities. In this manuscript, we report the synthesis of a novel water-soluble Pt(II) complex with the amino acid deoxyalliin (S-allyl-L-cysteine, sac), [Pt(sac)2], and its characterization by a set of chemical and spectroscopic techniques besides its preliminary antibacterial activity assays. Elemental and high-resolution mass spectrometric data (ESI-MS) indicated its 1:2 metal/ligand molar composition, with the molecular formula [Pt(C6H10NO2S)2]⋅H2O. The crystal structure of the complex was solved by single-crystal X-ray diffraction studies, where the two molecules of deoxyalliin were shown to be coordinated to the metal in a bidentate N,S-mode and in a trans-configuration. The 1H, 13C and 195Pt nuclear magnetic resonance (NMR) results and the infrared spectroscopic data reinforced the N,S-coordination of deoxyalliin to the metal. The coordination mode of the ligand was supported by density functional theory (DFT) calculations. The antibacterial activity of the complex was preliminarily evaluated by the minimum inhibitory concentration (MIC) assay. The experiments were performed for the complex and the free ligand over Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial strains. The [Pt(sac)2] complex did not show inhibitory effect in bacterial growth even at the highest concentration of 3.75 mmol L−1 considered in the present study.
Abietane diterpenes from sagittaria montevidensis ssp montevidensis Charm
(2007) Radke, Vanessa Soraia Cortez de Oliveira; Amaral, Maria do Carmo Estanislau do; Silva, Cleuza Conceição da; Oliveira, Cecília Maria Alves de; Tanaka, Clara Megumi Abe
Two new abietane-type diterpenes, 3β-hydroxy-9α, 13α-epidioxyabiet-8(14)-ene (1) and 3-oxo-9α,13α-epidioxyabiet-8(14)-ene (2), were isolated from the methanolic crude extract of the petioles of Sagittaria montevidensis ssp montevidensis (Alismataceae). The structures of 1 and 2 were determined on the basis of spectrometric analyses including HREIMS, IR as well as 1H and 13C 1 and 2D NMR.
Abietatrienes diterpenoids from Sagittaria montevidensis SSP Montevidensis
(2010) Tanaka, Clara Megumi Abe; Radke, Vanessa Soraia Cortez de Oliveira; Silva, Cleuza Conceição da; Nakamura, Celso Vataru; Oliveira, Pollyanna Laurindo de; Kato, Lucilia; Oliveira, Cecília Maria Alves de
The antimicrobial properties of the hexane, hexane/EtOAc and methanol fractions of the fresh petioles of Sagittaria montevidensis ssp montevidensis (Alismataceae) were evaluated against fungi and Gram-negative and Gram-positive bacteria. A new abietatriene-type diterpenoid, 3β,7α–dihydroxi-abieta-8,11,13-triene and the known 3β-hydroxy-abieta-8,11,13-trien-7-one were isolated from the most active fraction tested and the structures of these compounds were elucidated by data including IR, EIMS, and 1D and 2D NMR spectra.
Abordagem ambiental em livros didáticos de Química: princípios da carta de Belgrado
(2014-08) Cassiano, Karla Ferreira Dias; Echeverría, Agustina Rosa
Environmental approach in chemistry textbooks: principles of Belgrade letter. This article presents data from a survey that aimed to describe and analyze the environmental approach in chemistry textbooks approved by PNLEM/2008. It is a Content Analyze accomplished by justified categories of Environment Education (EE) based on Belgrade letter which articulates Scientific Knowledge, Knowledge/Awareness and Participation. The results pointed out that some themes are treated in a non contextualized way due to environmental dimension fragmentation which reduces the complexity of humanity-nature relationships. Although not all books fully contemplate the principles of the letter, and the overvaluation of Scientific Knowledge to the detriment of other crucial ones for the ecological condition, the research concluded that Chemistry textbooks can contribute to the accomplishment of EE in schools, emphasizing the necessity for studies about the relationship between the triad components “scientific contents, teacher training and textbook".
Abordagem de conceitos químicos em livros didáticos de ciências do 9º ano: do texto ao contexto
(2015) Costa, Mariangela Célia Souza; Mesquita, Nyuara Araujo da Silva
The schoolbooks is an important tool used by the teacher and the students, having a decisive role in the teaching and learning process as exerting major influences on conceptions of content. So the Science textbooks should present a collective and complex approach with respect to scientific knowledge, which are presented in a scientifically correct manner, with the appropriate language to the age of the series being worked on and with illustrations that may help in better understanding of the concepts. In this context, the present study investigated how the Science textbooks in ninth grade have been working chemistry concepts. This research, conducted qualitative approach, was based on a desk review of three books approved the PNLD. It was identified in the books analyzed, the presence of chemical and concepts with wrong or outdated and erroneous inclusion and presentation of unconventional ideas with science concepts.
Uma abordagem sobre o ensino de ciências e matemática no programa nacional de inclusão de jovens: do discurso a prática
(2010-12) Friedrich, Márcia; Benite, Claudio Roberto Machado; Benite, Anna Maria Canavarro
In an attempt to eradicate the illiteracy and treatment to students with age-grade distortions, the government of President Luis Inacio Lula da Silva (in his first term) implemented the Literate Brazil Program. In this context is the National Program for Inclusion of Youth: education, professional training and community action (PROJOVEM). In PROJOVEM the teaching of science and mathematics is recommended as a foundation in training and qualification for the job market aiming boost scientific and technological development of the country. This is a participatory research which reviews the proposal of pedagogical PROJOVEM. Concerning the education in science and mathematics: the PROJOVEM seems to satisfy, though precariously, only the certification for the school, or completion of specific degree of education. On this perspective introduces to restorative function as social debt, which indicates the restoration of a right denied: a school of quality.
Absence of genotoxic effects of the chalcone (E)-1-(2-hydroxyphenyl)-3-(4-methylphenyl)- prop-2-en-1-one) and its potential chemoprevention against DNA damage using in vitro and in vivo assays
(2017-02-16) Lima, Débora Cristina da Silva; Vale, Camila Regina do; Véras, Jefferson Hollanda; Valeze, Aline Bernardes; Noda Pérez, Caridad; Lee, Chen Chen
The chalcone (E)-1-(2-hydroxyphenyl)-3-(4-methylphenyl)-prop-2-en-1-one), or 2HMC, displays antileishmanial, antimalarial, and antioxidant activities. The aim of this study was to investigate the cytotoxic, genotoxic, mutagenic, and protective effects of 2HMC using the Ames mutagenicity test, the mouse bone marrow micronucleus test, and the comet assay in mice. In the assessment using the Ames test, 2HMC did not increase the number of His+ revertants in Salmonella typhimurium strains, demonstrating lack of mutagenicity. 2HMC showed no significant increase in micronucleated polychromatic erythrocyte frequency (MNPCE) in the micronucleus test, or in DNA strand breaks using the comet assay, evidencing absence of genotoxicity. Regarding cytotoxicity, 2HMC exhibited moderate cytotoxicity in mouse bone marrow cells by micronucleus test. 2HMC showed antimutagenic action in co-administration with the positive controls, sodium azide (SA) and 4-nitroquinoline-1- oxide (4NQO), in the Ames test. Co-administered and mainly pre-administered with cyclophosphamide (CPA), 2HMC caused a decrease in the frequency of MNPCE using the micronucleus test and in DNA strand breaks using the comet assay. Thus, 2HMC exhibited antimutagenic and antigenotoxic effects, displaying a DNA-protective effect against CPA, SA, and 4NQO carcinogens. In conclusion, 2HMC presented antimutagenic, antigenotoxic and moderate cytotoxic effects; therefore it is a promising molecule for cancer prevention.

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