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In a recent study, our research group demonstrated that the essential oil of Ocotea odorifera (EOOO) and its major compound safrole potentiated the action fluoroquinolones, modulating bacterial resistance possibly due to direct inhibition of efflux pumps. Thus, in the present study, we investigated whether these treatments could enhance the activity of gentamicin and erythromycin against multidrug-resistant (MDR) bacteria. The EOOO was extracted by hydrodistillation, and the phytochemical analysis was performed by gas chromatography coupled to mass spectrometry (GC–MS). The antibiotic-enhancing effect of the EOOO and safrole against MDR strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa was analyzed by the broth microdilution method. The chemical analysis confirmed the presence of safrole as a major component among the 16 compounds identified in the EOOO. Both the essential oil and the isolated compound showed clinically relevant antibacterial activities against S. aureus. Regarding the modulation of antibiotic resistance, the EOOO was found to enhance the activity of erythromycin against the strains of P. aeruginosa and S. aureus, as well as improving the action of gentamicin against S. aureus. On the other hand, safrole potentiated the activity of gentamicin against the S. aureus strain alone. It is concluded, therefore, that the EOOO and safrole can enhance the activity of macrolides and aminoglycosides, and as such are useful in the development of therapeutic tools to combat bacterial resistance against these classes of antibiotics.

Objective: Efflux pumps are transmembrane proteins associated with bacterial resistance mechanisms. Bacteria use these proteins to actively transport antibiotics to the extracellular medium, preventing the pharmacological action of these drugs. This study aimed to evaluate in vitro the antibacterial activity of 1,8-naphthyridines sulfonamides, as well as their ability to inhibit efflux systems of Staphylococcus aureus strains expressing different levels of the NorA efflux pump. Methods: The broth microdilution test was performed to assess antibacterial activity. Efflux pump inhibition was evaluated in silico by molecular docking and in vitro by fluorometric tests, and the minimum inhibitory concentration (MIC) was determined. The MIC was determined in the association between 1,8-naphthyridine and norfloxacin or ethidium bromide. Results: The 1,8-naphthyridines did not show direct antibacterial activity. However, they effectively reduced the MIC of multidrug-resistant bacteria by associating with norfloxacin and ethidium bromide, in addition to increasing the fluorescence emission. In silico analysis addressing the binding between NorA and 1,8-naphthyridines suggests that hydrogen bonds and hydrophilic interactions represent the interactions with the most favourable binding energy, corroborating the experimental data. Conclusion: Our data suggest that 1,8-naphthyridines sulfonamides inhibit bacterial resistance through molecular mechanisms associated with inhibition of the NorA efflux pump in S. aureus strains.

Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus are the primary bacteria that cause clinical infections, such as urinary and intestinal infections, pneumonia, endocarditis, and sepsis. Bacterial resistance is an innate natural occurrence in microorganisms, resulting from mutations or the lateral exchange of genetic material. This serves as evidence for the association between drug consumption and pathogen resistance. Evidence has demonstrated that the association between conventional antibiotics and natural products is a promising pharmacological strategy to overcome resistance mechanisms. Considering the large body of research demonstrating the significant antimicrobial activities of Schinus terebinthifolius Raddi, the present study aimed to evaluate the chemical composition and antibiotic-enhancing effects of Schinus terebinthifolius Raddi essential oil (STEO) against the standard and multidrug-resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The STEO was extracted by hydrodistillation using a Clevenger-type vacuum rotary evaporator. The Minimum Inhibitory Concentration (MIC) of the STEO was assessed by the microdilution method to evaluate the antibacterial activity. The antibiotic-enhancing activity of the essential oil was assessed by determining the MIC of antibiotics in the presence of a sub-inhibitory concentration (MIC/8) of the natural product. The GC-MS analysis revealed alpha-pinene (24.3%), gamma-muurolene (16.6%), and myrcene (13.7%) as major constituents of the STEO. The STEO potentiated the enhanced antibacterial activity of norfloxacin and gentamicin against all the strains and increased the action of penicillin against the Gram-negative strains. Therefore, it is concluded that although the STEO does not exhibit clinically effective antibacterial activity, its association with conventional antibiotics results in enhanced antibiotic activity.

The bacterial species Staphylococcus aureus presents a variety of resistance mechanisms, among which the expression of β-lactamases and efflux pumps stand out for providing a significant degree of resistance to clinically relevant antibiotics. The 1,8-naphthyridines are nitrogen heterocycles with a broad spectrum of biological activities and, as such, are promising research targets. However, the potential roles of these compounds on bacterial resistance management remain to be better investigated. Therefore, the present study evaluated the antibacterial activity of 1,8-naphthyridine sulfonamides, addressing their ability to act as inhibitors of β-lactamases and efflux pump (QacA/B and QacC) against the strains SA-K4414 and SA-K4100 of S. aureus. All substances were prepared at an initial concentration of 1024 μg/mL, and their minimum inhibitory concentrations (MIC) were determined by the broth microdilution method. Subsequently, their effects on β-lactamase- and efflux pump-mediated antibiotic resistance was evaluated from the reduction of the MIC of ethidium bromide (EtBr) and β-lactam antibiotics, respectively. The 1,8-naphthyridines did not present direct antibacterial activity against the strains SA-K4414 and SA-K4100 of S. aureus. On the other hand, when associated with antibiotics against both strains, the compounds reduced the MIC of EtBr and β-lactam antibiotics, suggesting that they may act by inhibiting β-lactamases and efflux pumps such as QacC and QacA/B. However, further research is required to elucidate the molecular mechanisms underlying these observed effects.

Abstract The Atlantic Forest is regarded a rich source of aromatic plants with a broad spectrum of biological properties. The leaves of seven Piper species were collected from the Atlantic Forest domain in the coastal region of Paraná state in winter (W) and spring (S). The volatile oils were extracted from the leaves through hydrodistillation method. The volatile oils were characterized by means of GC-FID and GC-MS. Sesquiterpenes were among the major compounds in all species studied, with many dozens of representatives. However, very low concentrations of monoterpenes were observed; α-pinene in Piper mosenii and P. cernuum, δ-3-carene in P. rivinoides, camphene and β-pinene in P. cernuum are exceptions. The arylpropanoides myristicine and elemicin were found in considerable amount in P. diospyrifolium (26.2%/S) and P. mosenii (16.4%/W), respectively. These oils were also screened for inhibitory activities against acetylcholinesterase (AChE) and α-glucosidase (AG). For AChE the most active samples were P. diospyrifolium, P. aduncum and P. cernuum, with inhibiting level > 93%. For the less sensitive AG, the most promising candidates were P. diospyrifolium and P. mosenii, with inhibiting level > 65%. These results highlight the importance of native plants as renewable source of new inhibitors for AChE and AG. Further investigation is required to identify the most active constituents or fractions from the selected volatile oils.

O presente ensaio aborda as categorias acumulação capitalista e trabalho a partir da perspectiva marxista, evidenciando a atualidade e o vigor das discussões dessa matriz teórica para compreensão da conjuntura atual. Buscou-se, na produção de Mészáros, os elementos para caracterizar o sociometabolismo do capital e o processo de acumulação capitalista com vistas a compreender as expressões do acirramento do processo de acumulação capitalista no mundo do trabalho. Para clarificar o debate, recorreu-se aos estudos de Ruy Mauro Marini que, ancorado na perspectiva marxista, analisa o desenvolvimento do Brasil e da América Latina. Nesta perspectiva, evidenciou-se a categoria “superexploração do trabalho” como um dos vetores do desenvolvimento das regiões periféricas no sistema capitalista mundializado. Essa discussão nos conduziu à centralidade da categoria trabalho, como a atividade que garante a sobrevivência da maioria da população, e que lhes dá identidade e reconhecimento. Por fim, concluímos com a importância e premência da construção teórica marxista tanto para desvelar a conjuntura atual quanto para tecer e subsidiar a luta social na construção de outra sociabilidade. Palavras-chave: Acumulação capitalista. Trabalho. Superexploração do Trabalho. Capitalist Accumulation And Labor: The Actuality And Vigor Of Marxist Theoretical Production ABSTRACT The presente article delas with the categories capitalista accumulation and work from the Marxist perspective, evidencing the actuality and the vigor of the discussions of this theoretical matrix for understanding the current conjuncture. The elements for characterizing the sociometabolismofthe capital werestudied in the production of Mészáros and the process of capitalist accumulation with a viewtounderstandingtheexpressionsoftheintensificationoftheprocessofcapitalistaccumulation in the world of work. To clarify the debate, were sort to the studies of Ruy Mauro Marini, anchored in the Marxist perspective, analyzing the development of Brazil and Latin America. In this perspective, the category "superexploitation of labor" was shown as one of the vectors of the development of peripheral regions in the globalized capitalist system. This discussion le dust othe centrality of the category of labor, as theactivitythatguaranteesthesurvivalofthemajorityofthepopulation, and which gives them identity and recognition. Concludes with the aimandurgency of the theoretical Marxist construction both tounveil the current conjuncture and toweave and subsidize the social struggle in the construction of the sociability. Keywords: Capitalistaccumulation. Labor. Superexploration of Labor.

Commercialized mouthwashes are generally expensive for the most financially vulnerable populations. Thus, several studies evaluate the antimicrobial potential of herbal products, such as essential oils, to reduce the activity of microorganisms in the mouth. The objective of this research was to carry out the chemical characterization and antibacterial activity of the essential oil of Piper mosenii (EOPm), providing data that enable the development of a low-cost mouthwash formulation aimed at vulnerable communities. The analysis of the antibacterial potential and modulator of bacterial resistance was verified by the microdilution method to determine the minimum inhibitory concentration-MIC. The chemical components were characterized by gas chromatography coupled to mass spectrometry, where 23 chemical constituents were detected, with α-pinene, being the major compound. The EOPm showed a MIC ≥ 1024 µg/mL for all bacterial strains used in the tests. When the EOPm modulating activity was evaluated together with chlorhexidine, mouthwash and antibiotics against bacterial resistance, the oil showed a significant synergistic effect, reducing the MIC of the products tested in combination, in percentages between 20.6% to 96.3%. Therefore, it is recommended to expand the tests with greater variation of EOPm concentration and the products used in this research, in addition to the evaluation of toxicity and in vivo tests, seeking the development of a possible formulation of mouthwash accessible to the vulnerable population.

Studies show that more consumers are using natural health products in the modern world. We have noticed a growing demand in markets and the professional community for mouthwashes that contain natural compounds. The objective of this study was to assess the chemical characterization and microbiological potential of the essential oil Piper arboreum (EOPa) to provide data to enable the development of a low-cost mouthwash. The evaluation of the antibacterial and bacterial resistance modulating activity was performed by the microdilution method to determine the minimum inhibitory concentration. The chemical components were characterized by gas chromatography coupled with mass spectrometry, which identified 20 chemical constituents, with caryophyllene oxide being one of the major compounds. The EOPa showed an MIC ≥ 1024 µg/mL for all bacterial strains used in the tests. When evaluating the modulating activity of EOPa combined with chlorhexidine, mouthwash and antibiotics against the bacterial resistance, the oil limited synergistic activity between the MIC of the products tested in combination (37% to 87.5%). Therefore, we recommend expanding the tests with greater variation in the EOPa concentration and the products used, as well as toxicity assessments and in vivo testing, with the purpose of the development of a possible low-cost mouthwash base that is accessible to the most vulnerable populations.

O presente artigo aborda alguns dos conceitos de violência e como eles se apresentam no cotidiano escolar, fazendo um paralelo entre essas definições e as vivências como estudante de iniciação a docência do curso de Artes em uma escola do município de Matinhos-PR. Para tanto, fizemos uma aproximação teórica com a categoria Violência, bem como uma análise das percepções, a partir do vivido. Percebemos que a promoção da cidadania e sua vivência plena, são formas de garantir a inclusão e o respeito ao o direito de todos os sujeitos no meio escolar

Este trabalho tem por objetivo apresentar uma importante planta medicinal e aromática: Siparuna guianensis Aublet, família Siparunaceae utilizada nos neotrópicos, e que vem sendo apontada por estudiosos como uma espécie prioritária de conservação para a região do cerrado. Estudou-se a variação da composição do óleo das folhas Siparuna guianensis de uma área de preservação ambiental no município de Cuiabá-MT, visando o manejo sustentável da espécie, o controle da matéria-prima utilizada como medicinal, bem como se avaliou sua potencial atividade sobre o sistema nervoso central

Este artigo apresenta os resultados de uma pesquisa realizada com uma turma de primeiro ano do ensino médio de uma escola do campo da rede pública do estado do Paraná. O objetivo foi observar como esses estudantes dialogam com as representações sociais sobre a juventude rural e o campo a partir de uma história em quadrinhos específica de Chico Bento. Nesse quadro, tendo como referência a produção teórica sobre consciência histórica de Jörn Rüsen; a relação entre sujeito e representações, foi interpelada como resultante das operações da consciência histórica, como coeficiente que permite aos indivíduos interpretar o mundo e a si mesmo, configurando parâmetros orientadores da vida prática no tempo. Nesse contexto, as interpretações dos estudantes foram compreendidas como especificidades do espaço no qual estão inseridos. Os resultados da pesquisa permitem compreender os distanciamentos, aproximações e diálogos do grupo pesquisado com os argumentos apresentados por Maurício de Souza Produções

Arctium species are known for a variety of pharmacological effects due to their diverse volatile and non-volatile secondary metabolites. Representatives of Arctium species contain non-volatile compounds including lignans, fatty acids, acetylenic compounds, phytosterols, polysaccharides, caffeoylquinic acid derivatives, flavonoids, terpenes/terpenoids and volatile compounds such as hydrocarbons, aldehydes, methoxypyrazines, carboxylic and fatty acids, monoterpenes and sesquiterpenes. Arctium species also possess bioactive properties such as anti-cancer, anti-diabetic, anti-oxidant, hepatoprotective, gastroprotective, antibacterial, antiviral, antimicrobial, anti-allergic, and anti-inflammatory effects. This review aims to provide a complete overview of the chemistry and biological activities of the secondary metabolites found in therapeutically used Arctium species. Summary of pharmacopeias and monographs contents indicating the relevant phytochemicals and therapeutic effects are also discussed, along with possible safety considerations.

Presently, results from a study carried out in this area using the essential oil from the Calyptranthes concinna species, a representative from the Myrtaceae family, are reported. The essential oil was obtained by hydrodistillation and gas chromatography coupled to mass spectrometry was used to identify its chemical constituents. Antibacterial activity was determined using the broth microdilution method, thus obtaining the Minimal Inhibitory Concentration (MIC) value, from which the subinhibitory concentration (MIC/8) was derived. The C. concinna essential oil presented antibacterial activity against both standard and multiresistant bacteria. In addition, the oil demonstrated an antibiotic activity potentiation against Staphylococcus aureus and Escherichia coli when in combination with the antibiotic gentamicin, reducing the MIC from 141.38 μg/mL and 208.63 μg/mL to 64 μg/mL and 128 μg/mL, respectively. Conclusions: Findings from the present study suggest this oil is promising in terms of its antimicrobial activity.

O Projeto Recicle ConsCIÊNCIA foi criado pela iniciativa de acadêmicos do curso de química da Universidade Federal do Mato Grosso - UFMT no ano de 2008. O projeto atua em escolas, associações, centro de educação profissional e tecnológica, além da própria Universidade. O objetivo do Recicle é levar a comunidade a reflexão sobre a biodiversidade e os meios de garantir a sustentabilidade com o uso racional dos recursos naturais. Neste contexto, o projeto apresenta-se também como espaço de formação profissional para os acadêmicos de química, tanto da licenciatura como do bacharelado. O projeto tem se tornado um espaço no qual o processo de construção se dá de forma coletiva e partilhada, sem desconsiderar a individualidade, mas promovendo a autonomia de cada membro.DOI: http://dx.doi.org/10.35700/ca.2015.ano2n2.p13-20.1560

The present article has as reference the reality of the graduates of the first four courses of the Coastal Sector of UFPR, this campus was created in 2005 through the process of expansion of the Brazilian universities. The results of our study point to the understanding of the professional insertion category as a multifaceted process that involves obtaining a job and a professional and contractual situation, constituted and influenced by a series of other elements such as social, political and economic characteristics of the region, the demands of the labor market, the initiatives of articulation of policies of education, youth and work, access to Higher Education institutions. The graduates interviewed are residents of the Coastal Region of Paraná State, or graduates who, after graduation, have remained in the region for a while. In this sense, the statements point to the importance of higher education at a Federal University in the region and the potential brought by this institution, related to the technological contribution, knowledge production and the dissemination of a more critical political culture in the face of regional challenges. ___ O presente artigo tem como referência a realidade dos diplomados dos quatro primeiros cursos do Setor Litoral da UFPR, campus criado em 2005 através do processo de expansão das universidades brasileiras ocorrido na época. Os resultados do nosso estudo apontam para a compreensão da categoria inserção profissional como um processo multifacetário que envolve a obtenção de um emprego e de uma situação profissional e contratual, constituída e influenciada por uma série de outros elementos, como as características sociais, políticas e econômicas da região, as demandas do mercado de trabalho, as iniciativas de articulação das políticas de educação, juventude e trabalho, o acesso às instituições de Ensino Superior. Os egressos entrevistados são residentes do litoral Paranaense, ou diplomados que, após a formatura, permaneceram na região por um tempo. Nesse sentido, as falas apontam para a importância da formação em nível superior em uma Universidade Federal na região e as potencialidades trazidas por essa instituição, referente ao aporte tecnológico, à produção de conhecimento e à disseminação de uma cultura política mais crítica frente aos desafios regionais.

O artigo discute o papel social e contraditório da Universidade, tendo como fundamento teórico a produção gramsciana, com destaque para a relação entre hegemonia, educação e intelectual orgânico, proposta pelo referido autor. As reflexões são circunstanciadas no território do Litoral do Paraná, lócus de atuação de um dos campi da Universidade Federal do Paraná. Na perspectiva de discutir as contribuições dessa instituição no debate de políticas públicas e no desenvolvimento da região, o texto discorre sobre alguns projetos e ações em andamento, bem como elenca demandas e potencialidades identificadas a partir da sistematização da prática docente nessa região, que envolve ensino, pesquisa e programas de extensão. A perspectiva gramsciana subsidia e reforça a necessidade de articulação com os movimentos sociais, a tessitura de uma nova sociabilidade, bem como a construção de práticas educativas emancipatórias.

Infections by multiresistant microorganisms have led to a continuous investigation of substances acting as modifiers of this resistance. By following this approach, the chemical composition of the essential oil from Piper caldense leaf and its antimicrobial potential were investigated. The antimicrobial activity was determined by broth microdilution method providing values for minimum inhibitory concentration (MIC), IC50, and minimum fungicidal concentration (MFC). The essential oil was tested as a modulator for several antibiotics, and its effect on the morphology of Candida albicans (CA) strains was also investigated. The chemical characterization revealed an oil composed mainly of sesquiterpenes. Among them are caryophyllene oxide (13.9%), spathulenol (9.1%), δ-cadinene (7.6%) and bicyclogermacrene (6.7%) with the highest concentrations. The essential oil showed very low activity against the strains of CA with the lowest values for IC50 and MFC of 1790 μg/mL and 8192 μg/mL, respectively. The essential oil modulated the activity of fluconazole against CA URM 4387 strain, which was demonstrated by the lower IC50 obtained, 2.7 μg/mL, whereas fluconazole itself presented an IC50 of 7.76 μg/mL. No modulating effect was observed in the MFC bioassays. The effect on fungal morphology was observed for both CA INCQS 40006 and URM 4387 strains. The hyphae projection was completely inhibited at 4096 μg/mL and 2048 μg/mL, respectively. Thus, the oil has potential as an adjuvant in antimicrobial formulations.

Este artigo tem o propósito de apresentar argumentos a favor da metodologia de ensino por projetos para a formação emancipatória dos sujeitos de aprendizagem. Para a construção das argumentações relatam-se as atividades desenvolvidas durante um semestre numa turma de Licenciatura em Ciências da UFPR Litoral. Além disso, utilizam-se as narrativas dos estudantes na avaliação final do semestre, buscando identificar as marcas diferenciais no processo percebido pelos mesmos. Destacaram-se os principais argumentos a favor da metodologia: há um favorecimento da pró-atividade dos estudantes, pois as aulas do tipo palestra deixam de ser o foco metodológico; o professor atua como mediador na medida em que junto com os estudantes organiza o estudo e as responsabilidades coletivas e individuais; a aprendizagem se dá num processo dialético em que se parte e se chega na prática social, possibilitando que o objeto deixe a assepsia conteudista e permita a construção de elaborações de pensamentos críticos a cerca de realidade concreta. À construção deste trabalho permitiu também a conclusão de que não é o uso da metodologia por projetos em si que favorece a formação emancipatória, mas a mediação, cuja lógica filosófica possibilite a elaboração de pensamentos críticos.

This work describes the volatile composition obtained by hidrodistillation of fresh leaves of Siparuna guianensis Aublet collected from Cuiabá (MT), Brazil. The composition of DCM extract of hydrolate was determined by GC-MS analysis and the results showed that the specie present a range of components according to their phenology and period of the leaves were collects. The highest volatile components yield was obtained during the reproductive period and the principal compound was the siparunone.

Sulfonamides obtained by reaction of 8-aminoquinoline with 4-nitrobenzenesulfonylchloride and 2,4,6-triisopropylbenzenesulfonyl chloride were used to synthesize coordination compounds with CuII and ZnII with a ML2 composition. Determination of the crystal structures of the resulting zinc and copper complexes by X-ray diffraction show a distorted tetrahedral environment for the [Cu(qnbsa)2], [Cu(qibsa)2] and [Zn(qibsa)2] complexes in which the sulfonamide group acts as a bidentate ligand through the nitrogen atoms from the sulfonamidate and quinoline groups. The complex [Zn(qnbsa)2] crystallizes with a water molecule from the solvent and the Zn is five-coordinated and shows a bipyramidal-trigonal geometry. The electrochemical and electronic spectroscopy properties of the copper complexes are also discussed.

O presente trabalho apresenta uma reflexão sobre o conceito de Ideologia, segundo John Thompson, buscando identificar questões marcantes no período da ditadura militar brasileira (1964-1985). Nesse sentido, exemplificamos algumas estratégias ideológicas utilizadas pelo governo militar para manter uma relação de dominação após o golpe e destacamos a política educacional adotada naquele período.