Pesquisa | SciELO

The aim of the current study was the valorization of hesperidin, the dominant flavonoid in citrus processing waste, by microwave-assisted synthesis of hesperidin-Mg complex, improving its antioxidant activity and insecticidal potential. Here we show, for the first time, that microwave-assisted synthesis of [Mg(hesp)2(phen)]OAc (1) (hesp: hesperidin, phen: phenanthroline) improve the reaction rate and yield. The nuclear magnetic resonance (NMR) experiments proved to be powerful tools for the identification of three isomers in metal complexes. Moreover, we explore the insecticidal potential of 1 and [Mg(phen)2(Isov)]OAc (2) (Isov : isovanillic acid) complexes against three insects. Complex 1 killed 80% of adults whitefly at 0.14 μmol L-1, and 2 76% at 0.36 μmol L-1. There was a total mortality of Spodoptera frugiperda with 2 at 0.39 μmol L-1, and 83% with 1 at 0.14 μmol L-1. Both have similar activity, and represent a novel group of insecticide for Bemisia tabaci and S. frugiperda; nevertheless, the benefits of both as Myzus persicae repellent require further evaluation.

https://doi.org/10.21577/0103-5053.20220050

Yersinia massiliensis (Enterobacteriales: Enterobacteriaceae) in the host Anaphes nitens (Hymenoptera: Mymaridae): first report of association with insects
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Ribeiro, M. F.

; Carvalho, V. R.

; Favoreto, A. L.

; De Marchi, B. R.

; Jordan, C.

; Zanuncio, J. C.

; Soares, M. A.

; Zanuncio, A. J. V.

; Wilcken, C. F.

Brazilian Journal of Biology

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2022, Volume 82 elocation e237098

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo As bactérias endossimbiontes podem afetar os parâmetros biológicos e reduzirem a eficácia de inimigos naturais no controle do inseto alvo. O objetivo deste trabalho foi identificar bactérias endossimbiontes em Anaphes nitens (Girault, 1928) (Hymenoptera: Mymaridae), o principal inimigo natural usado no manejo de Gonipterus platensis (Marelli, 1926) (Coleoptera: Curculionidae). O DNA genômico de seis populações de A. nitens foi extraído e as reações em cadeia da polimerase (PCR) realizadas com os primers para detectar bactérias endossimbiontes neste inseto. Os produtos de PCR foram amplificados, sequenciados e comparados com as sequências depositadas no GenBank para identificação das bactérias. Todas as populações de A. nitens tinham a bactéria Yersinia massiliensis (Enterobacteriales: Enterobacteriaceae). Esta bactéria foi originalmente descrita como de vida livre e está associada e compõe parte da microbiota de A. nitens. Este é o primeiro relato de Y. massiliensis em um hospedeiro.

Abstract Endosymbiont bacteria can affect biological parameters and reduce the effectiveness of natural enemies in controlling the target insect. The objective of this work was to identify endosymbiont bacteria in Anaphes nitens (Girault, 1928) (Hymenoptera: Mymaridae), the main natural enemy used to manage Gonipterus platensis (Marelli, 1926) (Coleoptera: Curculionidae). Genomic DNA from six A. nitens populations was extracted and polymerase chain reactions (PCR) were performed with the primers to detect endosymbiont bacteria in this insect. The PCR products were amplified, sequenced, and compared with sequences deposited in the GenBank for the bacteria identification. All A. nitens populations had the bacterium Yersinia massiliensis (Enterobacteriales: Enterobacteriaceae). This bacterium was originally described as free-living, and it is associated with and composes part of the A. nitens microbiota. This is the first report of Y. massiliensis in an insect host.

https://doi.org/10.1590/1519-6984.237098 187 downloads

COVID-19 in the Perioperative Period of Cardiovascular Surgery: the Brazilian Experience
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Gomes, Walter J.

; Rocco, Isadora

; Pimentel, Wallace S.

; Pinheiro, Aislan H. B.

; Souza, Paulo M. S.

; Costa, Luiz A. A.

; Teixeira, Marjory M. P.

; Ohashi, Leonardo P.

; Bublitz, Caroline

; Begot, Isis

; Moreira, Rita Simone L

; Hossne Jr, Nelson A.

; Vargas, Guilherme F.

; Branco, João Nelson R.

; Teles, Carlos A.

; Medeiros, Eduardo A. S.

; Sáfadi, Camila

; Rampinelli, Amândio

; Moratelli Neto, Leopoldo

; Rosado, Anderson Rosa

; Mesacasa, Franciele Kuhn

; Capriata, Ismael Escobar

; Segalote, Rodrigo Coelho

; Palmieri, Deborah Louize da Rocha Vianna

; Jardim, Amanda Cristina Mendes

; Vianna, Diego Sarty

; Coutinho, Joaquim Henrique de Souza Aguiar

; Jazbik, João Carlos

; Coutinho, Henrique Madureira da Rocha

; Kikuta, Gustavo

; Almeida, Zely Sant'Anna Marotti de

; Feguri, Gibran Roder

; Lima, Paulo Ruiz Lucio de

; Franco, Anna Carolina

; Borges, Danilo de Cerqueira

; Cruz, Felipe Ramos Honorato De La

; Croti, Ulisses Alexandre

; Borim, Bruna Cury

; Marchi, Carlos Henrique De

; Goraieb, Lilian

; Postigo, Karolyne Barroca Sanches

; Jucá, Fabiano Gonçalves

; Oliveira, Fátima Rosane de Almeida

; Souza, Rafael Bezerra de

; Zilli, Alexandre Cabral

; Mas, Raul Gaston Sanchez

; Bettiati Junior, Luiz Carlos

; Tranchesi, Ricardo

; Bertini Jr, Ayrton

; Franco, Leandro Vieira

; Fernandes, Priscila

; Oliveira, Fabiana

; Moraes Jr, Roberto

; Araújo, Thiago Cavalcanti Vila Nova de

; Braga, Otávio Penna

; Pedrosa Sobrinho, Antônio Cavalcanti

; Teixeira, Roberta Tavares Barreto

; Camboim, Irla Lavor Lucena

; Gomes, Eduardo Nascimento

; Reis, Pedro Horigushi

; Garcia, Luara Piovan

; Scorsioni, Nelson Henrique Goes

; Lago, Roberto

; Guizilini, Solange

Brazilian Journal of Cardiovascular Surgery

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Dez 2021, Volume 36 Nº 6 Páginas 725 - 735

Resumo: En | Texto: En | PDF: En

Abstract Introduction: We investigated the clinical course and outcomes of patients submitted to cardiovascular surgery in Brazil and who had developed symptoms/signs of coronavirus disease 2019 (COVID-19) in the perioperative period. Methods: A retrospective multicenter study including 104 patients who were allocated in three groups according to time of positive real time reverse transcriptase-polymerase chain reaction (RT-PCR) for the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2): group 1, patients who underwent cardiac surgery > 10 days after positive RT-PCR; group 2, patients with a positive RT-PCR within 10 days before or after surgery; group 3, patients who presented positive RT-PCR > 10 days after surgery. The primary outcome was mortality and secondary outcomes were postoperative complications, intensive care unit (ICU) length of stay, and postoperative days of hospitalization. Results: The three groups were similar with respect to age, the European System of Cardiac Operative Risk Evaluation score, and comorbidities, except hypertension. Postoperative complications and death were significantly higher in groups 2 and 3 than in group 1, and no significant difference between groups 2 and 3 was seen. Group 2 showed a high prevalence of surgery performed as an urgent procedure. Although no significant differences were observed in ICU length of stay, total postoperative hospitalization time was significantly higher in group 3 than in groups 1 and 2. Conclusion: COVID-19 affecting the postoperative period of patients who underwent cardiovascular surgery is associated with a higher rate of morbidity and mortality. Delaying procedures in RT-PCR-positive patients may help reduce risks of perioperative complications and death.

https://doi.org/10.21470/1678-9741-2021-0960

INSECTICIDAL AND FUNGICIDAL ACTIVITY OF A MAGNESIUM COMPOUND CONTAINING ISOVANILLIC ACID AGAINST LEAF-CUTTING ANT AND ITS SYMBIOTIC FUNGUS
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Silva, Eldevan S.

; Marchi, Rafael C.

; Matos, Carla Sthefane P.

; Silva, Maria Fátima G. F.

; Fernandes, João B.

; Bueno, Odair C.

; Carlos, Rose M.

Química Nova

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Mar 2021, Volume 44 Nº 3 Páginas 267 - 271

Resumo: En | Texto: En | PDF: En

Pesticides offer a simple, cost-effective solution to ensure food supplies for a growing world population. However, their environmental performance needs improvement if pesticides are to continue contributing importantly. This study explores the insecticidal potential of a magnesium (II) metal complex containing 1,10-phenanthroline and isovanillic acid (MgPhenIso) against leaf-cutting ant (Atta sexdens rubropilosa) and its symbiotic fungus (Leucoagaricus gongylophorus). The MgPhenIso complex is easy-to-prepare, stable in solid state and in aqueous solution, and resistant to sunlight irradiation. The insecticidal activity of MgPhenIso-containing bait against A. sexdens rubropilosa and L. gongylophorus showed a delayed action mode at 2 mg g-1 (100% kill, 6th day, S50=2b) and suppressed fungus development and growth. These results, together with earlier investigations on MgPhenIso regarding its absence of toxicity to Zebrafish and Wistar male rats, emphasize the potential of this complex as an environmentally friendly insecticide candidate.

https://doi.org/10.21577/0100-4042.20170693 101 downloads

Chemical characterization and antimicrobial activity of Campomanesia aurea against three strains of Listeria monocytogenes
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Pacheco, L. A.

; Ethur, E. M.

; Sheibel, T.

; Buhl, B.

; Weber, A. C.

; Kauffmann, C.

; Marchi, M. I.

; Freitas, E. M.

; Hoehne, L.

Brazilian Journal of Biology

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Fev 2021, Volume 81 Nº 1 Páginas 69 - 76

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo O óleo essencial (EO) das folhas de Campomanesia aurea foi analisado por CG-EM. O A planta foi coletada em abril (OEA) e outubro (OEO) em São Francisco de Assis/RS. Os óleos essenciais foram obtidos por hidrodestilação em aparelho Clevenger modificado. Os rendimentos foram de 4,44% em abril e 6,15% em outubro. Trinta e um compostos foram identificados no EOA, representando 96,87% do total, e vinte e oito compostos foram identificados no EOO, representando 99,46% do total. Para EOA, o principal monoterpeno identificado foi o p-cimeno (8,33%) e o principal sesquiterpeno identificado foi o α-candinol (10,72%), enquanto o EOO o maior monoterpeno identificado foi repetidamente Terpinolene (3,43%), enquanto o sesquiterpeno principal identificado foi α-cadinol (12,79%). A atividade antibacteriana do óleo essencial foi avaliada contra as três cepas de Listeria monocytogenes obtidas a partir da American Type Culture Collection (isolados ATCC 7644, 19114 and 13932). O óleo essencial apresentou uma CIM de 10 mg/mL contra as cepas ATCC 7644. e 19114, com efeito bacteriostático de 20 mg/mL e MIC de 20 mg/mL para ATCC 13932. Quanto à atividade antibiofilme, o EOO apresentou os melhores resultados com uma inibição de 90% no crescimento séssil com uma concentração aplicada de 4,0 mg/mL.

Abstract The essential oil (EO) composition of leaves of Campomanesia aurea was analyzed by GC-MS. The plant was collected in April (EOA) and October (EOO) in São Francisco de Assis/RS. The essential oils were obtained by hydrodistillation in a modified Clevenger apparatus. The yields were 4.44% in April, and 6.15%, in October. Thirty-one compounds were identified in EOA, accounting for 96.87% of the total, and twenty-eight compounds were identified in EOO, accounting for 99.46% of the total. For EOA, the major identified monoterpene was p-cymene (8.33%) and the major identified sesquiterpene was α-cadinol (10.72%), while regarding EOO the major identified monoterpene was repeatedly Terpinolene (3.43%), whereas the major identified sesquiterpene was α-cadinol (12.79%). The antibacterial activity of the essential oil was evaluated against the three Listeria monocytogenes from the American Type Culture Collection (strains ATCC 7644, 19114 and 13932). The essential oil showed a MIC of 10 mg/mL against the strains ATCC 7644 and 19114, with bacteriostatic effect of 20 mg/mL and a MIC of 20 mg/mL for ATCC 13932. Regarding the antibiofilm activity, o EOO showed the best results with an inhibition of 90% in the sessile growth with an applied concentration of 4.0 mg/mL.

https://doi.org/10.1590/1519-6984.219889 534 downloads

Association between SNP rs527616 in lncRNA AQP4-AS1 and susceptibility to breast cancer in a southern Brazilian population
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Marchi, Rafael D.

; Mathias, Carolina

; Reiter, Gabriel A. K.

; Lima, Rubens Silveira de

; Kuroda, Flávia

; Urban, Cícero de Andrade

; Souza, Ricardo. L. R. de

; Gradia, Daniela F.

; Ribeiro, Enilze M. S. F.

; Cavalli, Iglenir J.

; Oliveira, Jaqueline Carvalho de

Genetics and Molecular Biology

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2021, Volume 44 Nº 1 elocation e20200216

Resumo: En | Texto: En | PDF: En

Abstract Breast cancer (BC) is the leading cause of death by this disease in women worldwide. Among the factors involved in tumorigenesis, long non-coding RNAs (lncRNAs) and their differential expression have been associated. Differences in gene expression may be triggered by variations in DNA sequence, including single nucleotide polymorphisms (SNPs). In the present study, we analyzed the rs527616 (C>G), located in the lncRNA AQP4-AS1, using PCR-SSP in 306 BC patients and 312 controls, from a Brazilian population. In the BC group, the frequency found for CG heterozygotes was above the expected and the overdominant model is the best one to explain our results (OR: 1.70, IC 95%: 1.23-2.34, P<0.001). Furthermore, the SNP were associated with age at BC diagnosis and the risk genotype more frequent in the older age group. According to TCGA data, AQP4-AS1 is down-regulated in BC tissue, and the overexpression is associated with better prognoses, including Luminal A, HER2-, stage 1 of disease and smaller tumor. In conclusion, the CG genotype is associated with increased susceptibility in the southern Brazilian population. This SNP is mapped in the lncRNA AQP4-AS1, showing differential expression in BC samples. Based on these results, we emphasize the potential of the role of AQP4-AS1 in cancer.

https://doi.org/10.1590/1678-4685-gmb-2020-0216 788 downloads

On the effects of solar radiation pressure on the deviation of asteroids
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Marchi, L. O.

; Sanchez, D. M.

; Venditti, F. C. F.

; Prado, A. F. B A.

; Misra, A. K.

Revista mexicana de astronomía y astrofísica

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2021, Volume 57 Nº 2 Páginas 279 - 295

Resumo: En Es | Texto: En Es | PDF: En | PDF: Es

ABSTRACT In this work, we study the effects of solar radiation pressure (SRP) on the problem of changing the orbit of an asteroid to support planetary defense, scientific research, or exploitation of materials. This alternative considers a tethered reflective balloon (or a set of reflective balloons) attached to the asteroid, with a high area-tomass ratio, to use the SRP to deflect a potentially hazardous asteroid (PHA) or to approximate the target asteroid to Earth. The tether is assumed to be inextensible and massless, and the motion is described only in the orbital plane of the asteroid around the Sun. The model is then used to study the effects that the tether length, the reflectivity coefficient, and the area-to-mass ratio have on the deviation of the trajectory of the asteroid.

RESUMEN Estudiamos los efectos de la presión de la radiación solar (SRP) sobre el problema de la modificación de la órbita de un asteroide para propósitos de defensa planetaria, investigación científica o explotación de materiales. Consideramos un globo reflector (o un conjunto de ellos) sujeto con una correa al asteroide, con una relación área-masa grande, para utilizar la SRP para desviar a un asteroide potencialmente dañino (PHA), o para aproximar al asteroide a la Tierra. Suponemos que la correa es inextensible y de masa cero. El movimiento se describe sólo en el plano orbital del asteroide en torno al Sol. El modelo se usa para estudiar los efectos de la longitud de la correa, el coeficiente de reflectividad y el cociente área-masa sobre la desviación de la trayectoria del asteroide.

https://doi.org/10.22201/ia.01851101p.2021.57.02.03 121 downloads

Dynamics around an asteroid modeled as a mass tripole
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Santos, L. B. T.

; Marchi, L. O.

; Sousa-Silva, P. A.

; Sanchez, D. M.

; Aljbaae, S.

; Prado, A. F. B. A.

Revista mexicana de astronomía y astrofísica

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2020, Volume 56 Nº 2 Páginas 269 - 286

Resumo: En Es | Texto: En Es | PDF: En | PDF: Es

ABSTRACT The orbital dynamics of a spacecraft orbiting around irregular small celestial bodies is a challenging problem. Difficulties to model the gravity field of these bodies arise from the poor knowledge of the exact shape as observed from the Earth. In order to understand the complex dynamical environment in the vicinity of irregular asteroids, several studies have been conducted using simplified models. In this work, we investigate the qualitative dynamics in the vicinity of an asteroid with an arched shape using a tripole model based on the existence of three mass points linked to each other by rods with given lengths and negligible masses. We applied our results to some real systems, namely, asteroids 8567, 243 Ida and 433 Eros and also Phobos, one of the natural satellites of Mars.

RESUMEN La dinámica orbital de un satélite en torno a un cuerpo celeste irregular es un problema abierto. La dificultad de modelar el campo gravitatorio de esos cuerpos surge del pobre conocimiento que tenemos sobre sus formas, al observarlos desde la Tierra. Para entender el complejo entorno dinámico de los asteroides irregulares se han propuesto modelos simplistas. En este trabajo, investigamos cualitativamente la dinámica en el entorno de un asteroide en forma de arco, mediante un modelo de tripolo basado en tres puntos masa unidos por barras de longitudes determinadas y masas despreciables. Aplicamos nuestros resultados a algunos cuerpos reales, como el asteroide 8567, el 243 Ida, y el 433 Eros, así como a Phobos, uno de los satélites naturales de Marte.

https://doi.org/10.22201/ia.01851101p.2020.56.02.09 137 downloads

Determination of Antibiotics Residues in Milk Using a QuEChERS Method Using Full Factorial Design and Liquid Chromatography-Tandem Mass Spectrometry
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Grabsk, Andressa H. A.

; Souza, João Raul B. de

; Marchi, Francilaine E. De

; Prado, Rodolpho M. do

; Santos, Geraldo T. dos

; Porto, Carla

; Pilau, Eduardo J.

Journal of the Brazilian Chemical Society

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Jul 2019, Volume 30 Nº 7 Páginas 1498 - 1505

Resumo: En | Texto: En | PDF: En

This study evaluated different methods of extraction based on quick, easy, cheap, effective, rugged and safe (QuEChERS) method for analysis of the antibiotics ceftiofur, cloxacillin and enrofloxacin in milk using ultra-performance liquid chromatography-tandem mass spectrometry. The QuEChERS acetate method has been shown to be inefficient for extracting such antibiotics. The optimized QuEChERS method presented excellent recoveries, from 95 to 99%. A complete factorial design was used to evaluate the effects of variables of the clean-up step: anhydrous octadecylsilane (C18), primary secondary amine (PSA) and sodium acetate (NaAc). Linearity (R2) above 0.96 was achieved for all compounds. Accuracy and precision were assessed by recovery. Accuracy was 91-99%. Intraday precision with relative standard deviations (RSD) lower than 12.3% and interday precision lower than 12.4% were obtained. Limits of detection (LOD) and quantification (LOQ) were obtained between 1.4-6.8 and 1.5-8.7 µg L-1, respectively. The applicability was evaluated using 91 real milk samples.

https://doi.org/10.21577/0103-5053.20190046 1107 downloads

10.

Verbal instruction does not change myoelectric activity during seated row exercise in trained and untrained men
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Fujita, Rafael A.

; Marchi, Pedro U. De

; Silva, Nilson R. S.

; Gomes, Matheus M.

Motriz: Revista de Educação Física

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2019, Volume 25 Nº 4 elocation e10190100

Resumo: En | Texto: En | PDF: En

Abstract Aims: This study aimed to analyze the effect of verbal instruction on myoelectric activity (EMG) of the elbow flexors and shoulder extensors muscles during seated row exercise at 70%1RM, in trained and untrained individuals. Methods: The study sample comprised of seven males (21 ± 1.9 years) who had not practiced resistance training for at least one year (untrained group), and eight males (23 ± 2.6 years) who had regularly practice strength training for 2.4 ± 0.7 years (trained group). All individuals performed the seated row exercise with 70%1RM in conditions with and without verbal instruction. The EMG of the latissimus dorsi, teres major, posterior deltoid, triceps brachii long head and biceps brachii were measured. Results: There was no effect of verbal instruction on EMG at any muscle analyzed, for both groups. There was a difference between groups only for the teres major and triceps brachii (p < 0.05). Untrained individuals had greater myoelectric activity in teres major and triceps brachii long head muscles compared to the trained group during the exercise.

https://doi.org/10.1590/s1980-6574201900040100 922 downloads

11.

Possible effects of clustering structure in the competition between fast emission processes and compound nucleus decay
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Fabris, D.

; Gramegna, F.

; Cicerchia, M.

; Marchi, T.

; Barlini, S.

; Piantelli, S.

; Bini, M.

; Bruno, M.

; Casini, G.

; Cinausero, M.

; D’Agostino, M.

; Degerlier, M.

; Gelli, N.

; Mantovani, G.

; Morelli, L.

; Mabiala, J.

; Olmi, A.

; Pasquali, G.

; Poggi, G.

; Valdré, S.

; Vardaci, E.

; Fotina, O.V.

; Kravchuk, V.L.

; Colonna, M.

; Ono, A.

Nucleus

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Jun 2018, Nº 63 Páginas 19 - 24

Resumo: En Es | Texto: En Es | PDF: En | PDF: Es

Abstract The attention to nuclear clustering has been renewed due to the study of weakly bound nuclei at the drip lines. In particular, clustering structural properties in medium-mass systems have been studied by looking at the competition between the evaporation and pre-equilibrium particle emission in central collisions. Although for light nuclei at an excitation energy close to the particle separation value there are experimental evidence of such structure effects, this is still not the case for heavier systems since the determination of pre-formed clusters within nuclear matter is less obvious. Two systems, leading to the same 81Rb* compound nucleus, have been studied at the same beam velocity 16 AMeV: 16O + 65Cu and 19F + 62Ni. The experiment has been performed using the GARFIELD + RCo detection system installed at the Legnaro National Laboratories.Light charged particles energy distributions and multiplicities have been compared with different statistical and dynamical model calculations. From the first comparison between the two systems a difference in the fast α-decay channel has been evidenced, which can be related to the difference in the projectile structure. Recent data analysis results and comparisons with model calculations are presented in this contribution.

Resumen La atención a la agrupación nuclear se ha renovado debido al estudio de núcleos débilmente unidos en las líneas de goteo. En particular, se han estudiado las propiedades estructurales del agrupamiento en sistemas de masa media al observar la competencia entre la evaporación y la emisión de partículas de preequilibrio en colisiones centrales. Aunque para núcleos ligeros a una energía de excitación cercana al valor de separación de la partícula hay evidencia experimental de tales efectos de estructura, este no es el caso para sistemas más pesados ya que la determinación de agrupamientos preformados dentro de la materia nuclear es menos obvia. Se han estudiado dos sistemas, que conducen al mismo núcleo compuesto 81Rb *, a la misma velocidad de haz 16 AMeV: 16O + 65Cu y 19F + 62Ni. El experimento se ha realizado utilizando el sistema de detección GARFIELD + RCo instalado en los Laboratorios Nacionales Legnaro. Las distribuciones de energía y las multiplicidades de partículas de carga ligera se han comparado con diferentes cálculos de modelos estadísticos y dinámicos. Desde la primera comparación entre los dos sistemas, se ha evidenciado una diferencia en el canal de desintegración α rápida, que se puede relacionar con la diferencia en la estructura del proyectil. En esta contribución se presentan los resultados del análisis de datos recientes y las comparaciones con los cálculos del modelo.

12.

Easy Method for Removal of Cyanogens from Cassava Leaves with Retention of Vitamins and Omega-3 Fatty Acids
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Pereira, Iasmine G.

; Vagula, Julianna M.

; Marchi, Denis F.

; Barão, Carlos E.

; Almeida, Gleice R. S.

; Visentainer, Jesuí V.

; Maruyama, Swami A.

; Santos Júnior, Oscar O.

Journal of the Brazilian Chemical Society

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Jun 2016, Volume 27 Nº 7 Páginas 1290 - 1296

Resumo: En | Texto: En | PDF: En

Currently there is a crescent interest regarding the use of vegetable by-products for food fortification, in order to improve its nutritional quality. Cassava leaves are suitable as nutritional additives, however their cyanide content must be reduced to below 10 mg kg-1 of dry product. Thus, it was developed a method in drying laboratory oven which is able to reduce 99.85% of cyanide present in manioc leaves (from 35 mg kg-1 to 0.05 mg kg-1) while being 509% faster than the traditional method, and without substantial loss of omega-3 fatty acids and β-carotene.

https://doi.org/10.5935/0103-5053.20160027 5512 downloads

13.

Otimização e validação de uma metodologia analítica para determinação de 1-hidroxipireno em urina de cortadores de cana-de-açúcar
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Sakiara, K. A.

; Andrade, S. J. De

; Marchi, M. R. R.

; Vilegas, W.

; Bosso, R. M. V.

; Conforti-Froes, N. D. T.

Eclética Química

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- SciELO Analytics

2010, Volume 35 Nº 4 Páginas 113 - 119

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Este trabalho teve como objetivo otimizar e validar uma metodologia analítica para determinação de 1-hidróxipireno em urina de trabalhadores envolvidos na colheita da cana-de-açúcar. O método utilizado para determinação de 1-hidroxipireno em urina humana utilizado consiste na hidrólise enzimática, extração e clean-up por extração em fase sólida (SPE) e quantificação por cromatografia líquida de alta eficiência com detector de fluorescência (CLAE/Flu). Quatro tipos de cartuchos foram testados para verificação da porcentagem de recuperação. Urina de cortadores de cana-de-açúcar (não-fumantes e de ambos os sexos) foram coletadas no período da safra (n=39) e entressafra (n=34) da cana-de-açúcar. Os melhores resultados de recuperação foram atribuídos aos cartuchos C18. Os mesmos apresentaram recuperação entre 79% e 108%, com coeficiente de variação entre 5% e 10%. O limite de quantificação do método foi de 74 ng de 1-hidroxipireno por litro de urina. A metodologia otimizada e validada foi utilizada para determinação de amostras reais. Os resultados encontrados na urina dos trabalhadores no período da safra variaram de 0,026 a 2,3 μmol de 1-hidroxipireno por mol de creatinina. No período da entressafra os resultados variaram de 0,0023 a 0,38 μmol de 1-hidroxipireno por mol de creatinina. A metodologia validada mostrou-se adequada para determinação de 1-hidroxipireno em urina humana. Os dados obtidos permitem concluir que há forte correlação entre excreção de 1-hidroxipireno e os períodos de safra e entressafra da cana de açúcar.

This study aimed to optimize and validate an analytical methodology for determination of 1-hydroxypyrene in urine of workers involved in harvesting sugar cane. The method used for determining 1-hydroxypyrene in human urine is the enzymatic hydrolysis, extraction and clean-up by solid phase extraction (SPE) and quantified by high performance liquid chromatography with fluorescence detection (HPLC / Flu). Four types of cartridges were tested to verify the percentage of recovery. Urine of sugar-cane workers (non-smokers and of both sexes) were collected during the harvest (n = 39) and non-harvest season (n = 34) of cane sugar. The best recovery results were attributed to the C18 cartridges. They presented recovery between 79% and 108%, with a coefficient of variation between 5% and 10%. The limit of quantification was 74 ng of 1-hydroxypyrene per liter of urine. The optimized and validated methodology was used for determination of real samples. The results found in the urine of workers at harvest period ranged from 0.026 to 2.3 μmol of 1-hydroxypyrene per mol creatinine. During the non-harvesting season the results ranged from 0.0023 to 0.38 μmol of 1-hydroxypyrene per mol creatinine. The validated methodology proved suitable for determination of 1-hydroxypyrene in human urine. The data indicate that there is strong correlation between excretion of 1-hydroxypyrene and the periods during and between harvests of sugar cane.

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14.

Evaluation of methods for detection and identification of Mycobacterium species in patients suspected of having pulmonary tuberculosis
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Marchi, A. M.

; Juttel, I. D.

; Kawacubo, E. M.

; Dalmarco, E. M.

; Blatt, S. L.

; Cordova, C. M. M.

Brazilian Journal of Microbiology

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Dez 2008, Volume 39 Nº 4 Páginas 613 - 618

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

A tuberculose é um dos agravos prioritários para as políticas do Ministério da Saúde. No presente trabalho, o método de detecção de Mycobacterium tuberculosis pela Reação em Cadeia da Polimerase (PCR) em amostras de escarro foi padronizado e o diagnóstico laboratorial da tuberculose pulmonar foi avaliado, comparando-se as metodologias de baciloscopia, cultura e PCR. Foram analisadas 117 amostras de escarro de diferentes pacientes com suspeita de tuberculose pulmonar, com solicitação de baciloscopia. A baciloscopia foi realizada com a coloração de Ziehl-Neelsen e a cultura pela semeadura das amostras em meio de Lowenstein-Jensen, incubadas a 37ºC por oito semanas. Para realização da PCR, o DNA foi amplificado com um par de oligonucleotídeos específicos para o complexo M. tuberculosis, resultando em um produto de 123 pb do elemento de inserção IS6110. Das 117 amostras analisadas, três (2,56%) apresentaram baciloscopia positiva e PCR positiva para M. tuberculosis (concordância de 100%), e nove (7,69%) tiveram crescimento de Mycobacterium sp. na cultura (P= 0,1384). Das seis amostras que tiveram resultado positivo somente por cultura, uma foi identificada ainda como pertencente ao complexo M. tuberculosis por PCR-RFLP, e outra foi identificada como micobactéria não tuberculosa. A sensibilidade e a especificidade da baciloscopia e da PCR em relação à cultura foram 33,3% e 100%, respectivamente.

Tuberculosis control is a priority for the Ministry of Health policies in Brazil. In the present work, the detection of Mycobacterium tuberculosis by the Polymerase Chain Reaction (PCR) was standardized, and the laboratory diagnosis of pulmonary tuberculosis was evaluated comparing baciloscopy, culture and PCR tests. The study was carried out with 117 sputum samples from different patients suspected of having pulmonary tuberculosis, for whom physicians had ordered a baciloscopy test. Baciloscopy was performed using the Ziehl-Neelsen method, and culture was performed by incubation of treated samples in Lowenstein-Jensen's medium at 37ºC for eight weeks. For PCR, DNA was amplified with a specific pair of primers to the M. tuberculosis complex, with a resulting product of 123 bp from the insertion element IS6110. Three (2.56%) samples presented a positive baciloscopy result and a positive PCR result (100% agreement), and nine (7.69%) presented Mycobacterium sp. growth in culture (P= 0.1384). Among six samples with positive results in culture, one was identified by PCR-RFLP as belonging to the M. tuberculosis complex and one was identified as a non-tuberculosis mycobacteria. Sensitivity and specificity of PCR compared to culture were 33.3% and 100%, respectively.

2785 downloads Citado 6 vezes em SciELO

15.

Synthesis, screening for antiacetylcholinesterase activity and binding mode prediction of a new series of [3-(disubstituted-phosphate)-4,4,4-trifluoro-butyl]-carbamic acid ethyl esters
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Zanatta, Nilo

; Borchhardt, Deise M.

; Carpes, Adriana D.

; Marchi, Tiago M.

; Andricopulo, Adriano D.

; Salum, Lívia B.

; Schetinger, Maria R. C.

; Bonacorso, Helio G.

; Martins, Marcos A. P.

; Flores, Alex F. C.

Journal of the Brazilian Chemical Society

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2008, Volume 19 Nº 6 Páginas 1118 - 1124

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Uma nova série de nove 3-fosfato-(4,4,4-trifluor-butil)-carbamatos de etila (compostos fosfato-carbamato), foram obtidos através da reação de (4,4,4-trifluor-3-hidroxibut-1-il)-etil carbamatos com oxicloreto de fósforo seguido de adição de álcoois. Os produtos foram caracterizados por espectroscopia de RMN de ¹H, 13C, 31P e 19F, CG-EM e análise elementar. Todos os compostos sintetizados foram testados para a inibição da enzima acetilcolinesterase (AChE) usando o método de Ellman. Todos os compostos analisados contendo os grupos carbamato e fosfato em sua estrutura, mostraram inibição enzimática, sendo que o composto contendo o grupo dietóxi (2b) apresentou a maior atividade inibitória. Estudos de modelagem molecular foram realizados para obter informações detalhadas entre o sítio ativo da enzima acetilcolinesterase e os compostos candidatos a inibição, obtendo-se valiosas informações estruturais com relação à inibição de enzima acetilcolinesterase.

A series of nine new [3-(disubstituted-phosphate)-4,4,4-trifluoro-butyl]-carbamic acid ethyl esters (phosphate-carbamate compounds) was obtained through the reaction of (4,4,4-trifluoro-3-hydroxybut-1-yl)-carbamic acid ethyl esters with phosphorus oxychloride followed by the addition of alcohols. The products were characterized by ¹H, 13C, 31P, and 19F NMR spectroscopy, GC-MS, and elemental analysis. All the synthesized compounds were screened for acetylcholinesterase (AChE) inhibitory activity using the Ellman method. All compounds containing phosphate and carbamate pharmacophores in their structures showed enzyme inhibition, being the compound bearing the diethoxy phosphate group (2b) the most active compound. Molecular modeling studies were performed to investigate the detailed interactions between AChE active site and small-molecule inhibitor candidates, providing valuable structural insights into AChE inhibition.

1625 downloads

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