Polystyrene-b-poly (acrylic acid) nanovesicles coated by modified chitosans for encapsulation of minoxidil

Abstract In this work, polystyrene-b-poly (acrylic acid) (PS-b-PAA) nanovesicles were coated by modified chitosans aiming at studying its physicochemical parameters. The chitosan (CS) was chemically modified to add hydrophilic and/or hydrophobic groups, obtaining three modified chitosans. The PS-b-PAA nanovesicles were obtained by organic (1,4-dioxane) cosolvent method in water, resulting in nanovesicles with less than 150 nm of diameter (polydispersibility index - PDI at 90° = 0.106), measured by dynamic light scattering (DLS) and transmission electron microscopy (TEM), and negative zeta potential (-37.5 ± 3.2 mV), allowing the coating of its surface with oppositely charged polysaccharides, such as the CS and the modified chitosans. The coating process was made by mixing the colloidal suspensions with the CS and the modified chitosans at specific ENT#091;CS-xENT#093;/ENT#091;PS-b-PAAENT#093; ratios (0.001 to 1.0 wt %) and measuring the change in size and surface charge by DLS and zeta potential. Upon reaching maximum adsorption, the zeta potential parameter was positively stabilized (+26.7 ± 4.1 mV) with a hydrodynamic diameter slightly longer (< 200 nm of diameter). The encapsulation efficiency (EE) of minoxidil, quantified by capillary electrophoresis, was 50.7%, confirming their potential as drug delivery carriers and the coating process showed the possibility of controlling the surface charge nature of these nanovesicles

Poricoic acid A induces apoptosis and autophagy in ovarian cancer via modulating the mTOR/p70s6k signaling axis

Due to the high mortality and rapid disease progression, ovarian cancer remains one of the most common malignancies threatening the health of women. The present study was conducted to explore the anticancer effects and the underlying mechanisms of poricoic acid A (PAA), the main components of Poria cocos, on ovarian cancer. We investigated the anticancer effects of different concentrations of PAA in the SKOV3 cell line. Cell viability and proliferation were examined by CCK-8 assay. Cellular migration and invasion were assessed by the scratch and Transwell migration assays, respectively. The effect of PPA on cell apoptosis was measured by flow cytometry and caspase-3/8/9 colorimetric assay. Western blot was performed to detect protein level changes related to apoptosis and mTOR signaling pathways. The in vivo anticancer effect of PAA was evaluated using xenograft tumorigenesis model in nude mice. Our results showed that PAA suppressed SKOV3 cellular viability, migration, and invasion in a dosage-dependent manner. Flow cytometry results demonstrated PAA treatment could induce SKOV3 cell apoptosis. In addition, increased ratio of LC3-II/LC3-I (a marker for autophagosome formation) was observed after PAA treatment, as well as inhibition of m-TOR and p70s6k phosphorylation. In nude mice, PAA treatment reduced the xenograft tumor weight by 70% (P<0.05). In conclusion, our data suggested that PAA induced apoptosis and autophagy in ovarian cancer via modulating the mTOR/p70s6k signaling axis.

Novel Cathelicidin Antimicrobial Peptides from Paa robertingeri

This study aimed to describe two cathelicidins (cathelicidin-PR1 and cathelicidin-PR2) from the skin of Paa robertingeri (Anura: Ranidae). The deduced mature peptides cathelicidin-PR1 and cathelicidin-PR2 were composed of 29 and 25 residues, respectively. Cathelicidin - PR1 has higher antimicrobial activity it could kill Gram-positive and Gram-negative bacteria and even some fungal species. Cathelicidin-PR1 exhibited more effective than AMP in antimicrobial activity against Pseydomonas maltophilia clinical strain. On the contrary, cathelicidin-PR2 had very weak antimicrobial activity. Furthermore, cathelicidin-PR1 and cathelicidin-PR2 exhibited very low hemolytic activity against human erythrocytes and little hemagglutinating activity. The results suggested that the cathelicidin-PR1 might serve as a template for developing novel antibiotics.

Family farming and institutional markets: analysis of the perception of Universidade Federal de Pelotas restaurant goers about a preferential shopping system / Análise da percepção dos frequentadores dos restaurantes universitários da Universidade Federal de Pelotas sobre um sistema de compras preferenciais

ABSTRACT: The purpose of this article was to investigate the perception of the students of the school restaurants of the Federal University of Pelotas (UFPel) on a system of preferential purchases. This is done through public calls that give preference to production coming from the family agriculture of Pelotas and region. A semi-structured questionnaire (survey) was applied focusing on the level of knowledge and information of respondents on what is family farming, on the aforementioned system and their respective social developments. It was verified that there are differences of perception according to the area of knowledge of the respondents. Meanwhile, there is great convergence regarding the importance of this system for the regional economy.

RESUMO: O propósito do artigo é investigar a percepção dos frequentadores dos restaurantes universitários da Universidade Federal de Pelotas sobre um sistema de compras preferenciais. Este se dá através de chamadas públicas que dão primazia à produção oriunda da agricultura familiar de Pelotas e região. Foi aplicado um questionário semiestruturado (pesquisa tipo survey) centrado no nível de conhecimento e informação dos respondentes sobre o que é agricultura familiar, sobre o aludido sistema e seus respectivos desdobramentos sociais. Constatou-se que há diferenças de percepção segundo a área do conhecimento dos respondentes. Entretanto, há grande convergência no que tange à importância deste sistema para a economia regional e para o desenvolvimento dos territórios.

Agroecologia e políticas públicas: reflexões sobre um cenário em constantes disputas / Agroecology and public policies: reflections on a scenario in constants disputes / Agroecología y políticas públicas: reflexiones sobre un escenario en constantes disputas / Agroécologie et politiques publiques: réflexions sur un scénario en conflits constants

No atual contexto da agricultura a agroecologia vem se apresentando como uma importante alternativa ao modelo hegemônico do agronegócio. Uma das possibilidades de ampliação dessa perspectiva na agricultura brasileira vem sendo a implementação de políticas públicas com abertura para o enfoque agroecológico. No entanto, essa implementação ocorre em um cenário de inúmeras disputas e contradições. Nosso objetivo nesse artigo é discutir a inserção do enfoque agroecológico nas políticas públicas, tendo por foco o Programa de Aquisição de Alimentos (PAA) e o Programa Nacional de Alimentação Escolar (PNAE), refletindo acerca das potencialidades e limitações da inserção da agroecologia nesses programas no modo como vem sendo realizada. Como expressão dos avanços e fragilidades que aí se fazem presentes, apresentamos o relato de agricultores agroecologistas do Estado do Paraná sobre suas experiências de trabalho e o acesso a esses programas através de uma associação. Verificamos que as disputas no contexto da agricultura brasileira reverberam na maneira como vem ocorrendo a inserção da agroecologia nas políticas públicas. Frente a esse cenário, compreendemos ser imprescindível para a consolidação de políticas públicas de base agroecológica a organização e mobilização dos movimentos sociais e sua incidência em todo o processo de construção dessas políticas.

In the current agricultural context, the agroecology has been presenting itself as an important alternative to the hegemonic model of agribusiness. One of agroecology expansion opportunities in Brazilian agriculture has been the public policies implementation with opening for the agroecological approach. However this implementation happens in a full of disputes and contradictions scenario. Our aim in this paper is introduce a discussion about this, having as focus the Food Acquisition Program (PAA) and the National Program for School Food Supply (PNAE), thinking about potentialities and limits of agroecology insertion in these programs in the way how it has been done. As an expression of these advances and fragilities we introduce the report of an agroecologist about the peasant families access to these programs through an agroecologists farmers association in state of Paraná, Brazil. We founded that the disputes in the Brazilian agriculture context reverberate in the way as the agroecology inclusion in public policies is happening. Faced with this scenario, we understand to be essential for the consolidation of agroecological public policies, the organization and mobilization of social movements and their impact throughout the construction process of these policies.

En el contexto actual de la agricultura, la agroecología viene presentándose como una alternativa importante frente el modelo hegemónico de la agroindustria. Una de las oportunidades de expansión de agroecología en la agricultura brasileña ha sido la implementación de políticas públicas que se pueden apoyar un enfoque agroecológico. Sin embargo, esta implementación se lleva a cabo en un entorno de numerosos conflictos y contradicciones. Nuestro objetivo en este artículo es discutir la inserción del enfoque agroecológico en las políticas públicas, con el foco en el Programa de Adquisición de Alimentos (PAA) y el Programa Nacional de Alimentación Escolar (PNAE), lo que refleja las potencialidades y limitaciones de la inserción de la agroecología en estos programas en el camino que se ha llevado a cabo. Como expresión de los avances y debilidades que allí se hacen presentes, discutiremos la historia de agricultores agroecologistas del Estado de Paraná sobre el acceso a estos programas a través de una asociación. Se encontró que las diferencias en el contexto de la agricultura brasileña repercuten en la forma como se ha hecho la inclusión de la agroecología en las políticas públicas. Ante este escenario, entendemos que es esencial para la consolidación de la base de la política pública agroecológica, la organización y la movilización de los movimientos sociales y su impacto en todo el proceso de construcción de estas políticas.

Dans le contexte actuel de l'agriculture, l'agroécologie s'est présentée comme une alternative importante au modèle hégémonique de l'agro-industrie. L'une des possibilités d'élargir cette perspective dans l'agriculture brésilienne a été la mise en œuvre de politiques publiques ouvertes pour l'approche agroécologique. Cependant, cette mise en œuvre se produit dans un scénario de nombreux conflits et contradictions. Notre objectif dans cet article est de discuter de l'insertion de l'approche agroécologique dans les politiques publiques, en mettant l'accent sur le programme d'acquisition des aliments (AAP) et le Programme national d'alimentation scolaire (PNAE), une réflexion sur les potentialités et les limites de l'insertion de l'agroécologie dans ces programmes de la manière qu'il a été réalisée. Comme l'expression des avancées et des fragilités qui y son présentes, nous présentons un rapport des agricultrices agroécologistes dans l'État de Paraná sur leur expérience de travail et l'accès à ces programmes grâce à une combinaison. Nous avons constaté que les conflits dans le contexte de l'agriculture brésilienne réverberent dans la façon que l'agroécologie s'inclut dans les politiques publiques. Face à ce scénario, nous comprenons être essentiel pour la consolidation de la politique publique agroécologique l'organisation et la mobilisation des mouvements sociaux et leur impact tout au long du processus de construction de ces politiques.

Tandem expression and activity determination of antibacterial peptide Spinosan-C from Paa spinosa / 生物工程学报

Antibacterial peptide can be easily degraded by protease and has the lethal effect on the host Escherichia coli. In order to solve these problems and further improve the expression ability of the Escherichia coli system, the antimicrobial peptide Spinosan-C of Paa spinosa was studied. First, the codon of Spinosan-C was optimized according to E. coli codon usage frequency. Then, the 8 multimeric Spinosan-C gene (8×Spinosan-C) was synthesized and cloned into prokaryotic expression vector pET-28a. The fusion antimicrobial peptide 8×Spinosan-C was further highly expressed in Escherichia coli strain Rosetta. The recombinant 8×Spinosan-C protein was then purified and cleaved specially by formic acid to generate the Spinosan-C monomer. Antibacterial test in vitro suggested that the cleaved Spinosan-C monomer had antibacterial bioactivity against the test bacteria. This study provides a technical reference for the largescale preparation of frog antimicrobial peptides.

Effect of peracetic acid on biofilms formed by Listeria monocytogenes strains isolated from a Brazilian cheese processing plant

ABSTRACT This study aimed to investigate the effect of peracetic acid (PAA, 0.5%) on adherent cells of three strains of Listeria monocytogenes strains belonging to serotypes 4b and 1/2b that had been previously isolated from the environment of a Brazilian cheese plant. The assays were conducted using polystyrene microplates and stainless steel coupons and the adhered cells were treated with PAA for 60, 120 and 180 s. On stainless steel, biofilms were partially inactivated by PAA after 60 s and almost 100% of the cells were damaged within 180 s using epifluorescence microscopy with LIVE/DEAD® staining. On polystyrene microplates, PAA decreased (P<0.05) biofilm biomass produced by the three L. monocytogenes isolates at 60 s, when compared with controls (no PAA treatment). However, PAA did not completely eliminate L. monocytogenes cells on polystyrene microplates (decreasing 1.8-2.5 log cycles after treatment with PAA for 180 s). The correct concentration and contact time of PAA is critical for eliminating biofilms formed by L. monocytogenes on stainless steel surfaces, although further studies are needed for defining efficient PAA treatments to remove adherent cells of this pathogen on plastic polymers

Prevalence of the paa gene (porcine attaching and effacing associated) in porcine enteropathogenic Escherichia coli (PEPEC) associated with postweaning diarrhea in south Brazil

Paa (porcine attaching and effacing associated) may be an important virulence factor E. coli of piglets with diarrhea. This study showed for the first time in Brazil the prevalence of the paa gene (22%) in E. coli strains isolated from piglets and these isolates also harboured genes for other adhesins and toxins LT II, STa and STb.

Avaliação da distribuição de reativos para diagnóstico in vitro destinados às ações de vigilância e controle de agravos / Evaluation of the distribution of in vitro diagnostic reagents for the surveillance and control of diseases

Neste trabalho apresentamos um panorama do armazenamento de reativos para diagnóstico in vitro distribuídos pelo Ministério da Saúde aos Laboratórios Centrais de Saúde Pública – LACEN, e da Central Nacional de Distribuição de Insumos Estratégicos – CENADI. Foi realizada avaliação normativa considerando-se os componentes de estrutura e processo, destacando-se a importância da adoção das Boas Práticas de Armazenamento - BPA, no aprimoramento dos processos de trabalho. Foram avaliados quinze LACEN nas cinco regiões brasileiras. Foram verificados itens de BPA adotados em cada unidade avaliada. Foi evidenciado que os setores de armazenamento das unidades laboratoriais e do nível central carecem de maiores investimentos em capacitação e, em alguns casos, em estrutura física. O planejamento das aquisições também foi abordado e mostrou-se insatisfatório, conforme evidenciado pelo indicador de desabastecimento. Acreditamos que os desafios e pontos positivos destacados neste estudo possam contribuir para a melhoria dos processos de planejamento, aquisição e armazenamento de reativos para diagnóstico in vitro no âmbito do MS.

EFFECT OF RSV M_(2-1) GENE EXPRESSION ON THE GROWTH OF HUMAN LUNG ADENOCARCINOMA PAa IN VIVO AND VITRO / 解放军医学杂志

To explore the the effect of RSV M 2-1 gene expression on the growth of human lung adenocarcinoma PAa cell line, the recombinant RSV M 2-1 gene eukaryotic plasmid PXJ 41/ M 2-1 was transfected to the human lung adenocarcinoma PAa cell line. Expression of the M 2-1 gene was examined by RT PCR and Western blot. The growth of the human lung adenocarcinoma PAa cell was observed by MTT curve, flow cytometry, the capacity of inherence, colony forming units and inoculation of nude mouse. The results showed that ①The desired fragments of M 2-1 gene were digested by restriction enzyme and RT PCR, respectively. ②The bands of M 2-1 gene protein were found by Western blot. ③ The ratio of transfected PAa cells in S phase of cell cycle was decreased, but increased in G 2 /M phase. Colony forming efficiency and units of the transfected PAa cell were increased, but the capacity of its inherence was decreased. ④Tumorogensising time of the transfected PAa cell in nude mouse was delayed, but its growing speed was increased. The tumor tissue transformed to some extent from adenocarcinoma to squamous carcinoma was found in the nude mouse. It is suggested that the M 2-1 gene may promote the growth of PAa cells, which may implicate some relationship between RSV and lung cancer.