Volatiles from Subtropical Convolvulaceae That Interfere with Bacterial Cell-to-Cell Communication as Potential Antipathogenic Drugs

Increasing chronic bacterial infections create an urgent need for new antimicrobial agents or strategies for their control. Targetingvirulence is one of the alternative approaches to find new medicines to treat persistent infections due to bacteria with biofilmphenotypewhich are more resistant to antibiotics than their planktonic counterparts having an extreme capacity for evading the host defences. A bioguided study of sixteen extracts from flowers and leaves of four subtropical Convolvulaceae species provided evidence of the occurrence of antipathogenic natural products active against Gram positive and negative bacteria.Particularly, volatile metabolites from Merremia dissecta creeper, a food and medicinal plant, were able to interfere with the Pseudomonas aeruginosa quorum sensing system by a strong decrease of N-acyl homoserine lactone (AHL) biosynthesis (63?75%), which attenuated the virulence factor expression like biofilm (55%) and elastase activity (up to 27%), key factors thatenable the colonization and dissemination of the infection in the host. Control of the P. aeruginosa biofilm and the QS process by phytochemicals, such as (+) spathulenol, isolated from a bioactive extract of M. dissecta leaves would be a good strategy for the development of new and effective antipathogenic drugs.Fil: Luciardi, María Constanza. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Pérez Hernández, María Victoria. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Muruaga, Nora. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Cartagena, Elena. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentin

Evolution and emergence of plant viruses

[EN] Viruses are common agents of plant infectious diseases. During last decades, worldwide agriculture production has been compromised by a series of epidemics caused by new viruses that spilled over from reservoir species or by new variants of classic viruses that show new pathogenic and epidemiological properties. Virus emergence has been generally associated with ecological change or with intensive agronomical practices. However, the complete picture is much more complex since the viral populations constantly evolve and adapt to their new hosts and vectors. This chapter puts emergence of plant viruses into the framework of evolutionary ecology, genetics, and epidemiology. We will stress that viral emergence begins with the stochastic transmission of preexisting genetic variants from the reservoir to the new host, whose fate depends on their fitness on each hosts, followed by adaptation to new hosts or vectors, and finalizes with an efficient epidemiological spread.We acknowledge the financial support from the Spanish Dirección General de Investigación Científica y Técnica grants BFU2012-30805 (S. F. E.) and AGL2008-02458 (F. G. A.)Elena Fito, SF.; Fraile, A.; García-Arena, F. (2014). Evolution and emergence of plant viruses. Advances in Virus Research. (88):161-191. https://doi.org/10.1016/B978-0-12-800098-4.00003-9S1611918

Histological changes of Berberis mikuna pollen grains in relation to viability and germinability

Berberis mikuna is a spontaneous shrub grown in the Tucuman-Bolivian subtropical jungle area and its fruits were highly prized as food by diaguitas and calchaquies who were local populations. Fruits are rich in phenolic compounds which would be responsible for the beneficial properties for health. Pollen preservation in gene banks should be implemented as standard procedures since pollen is a useful source of diverse alleles within a gene pool. Therefore, the aim of this work was to study the histological and ultrastructural changes of pollen grains after 45 days of conservation at different temperatures. Berberis mikuna pollen grain germination and viability decreased significantly after 45 days of its collection. Germination and viability decreased with increasing storage temperature, although the viability in T45 Ref and T45 Fr was similar. Ultrastructure studies revealed differences in the fibrillar structure of the intine, as well as the decrease in starch reserve in pollen grains stored at 5 °C andat room temperature.Fil: Radice, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Moron. Facultad de Agronomia y Ciencias Agroalimentarias. Laboratorio de Investigaciones En Fisiología Vegetal; ArgentinaFil: Galati, Beatriz Gloria. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Botánica General; ArgentinaFil: Zarlavsky, Gabriela Elena. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Botánica General; ArgentinaFil: Arena, Miriam Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Moron. Facultad de Agronomia y Ciencias Agroalimentarias. Laboratorio de Investigaciones En Fisiología Vegetal; Argentin

Lemon oils attenuate the pathogenicity of pseudomonas aeruginosa by quorum sensing inhibition

The chemical composition of three Citrus limon oils: lemon essential oil (LEO), lemon terpenes (LT) and lemon essence (LE), and their influence in the virulence factors production and motility (swarming and swimming) of two Pseudomonas aeruginosa strains (ATCC 27853 and a multidrug-resistant HT5) were investigated. The main compound, limonene, was also tested in biological assays. Eighty-four compounds, accounting for a relative peak area of 99.23%, 98.58% and 99.64%, were identified by GC/MS. Limonene (59–60%), γ-terpinene (10–11%) and β-pinene (7–15%) were the main compounds. All lemon oils inhibited specific biofilm production and bacterial metabolic activities into biofilm in a dose-dependent manner (20–65%, in the range of 0.1–4 mg mL−1) of both strains. Besides, all samples inhibited about 50% of the elastase activity at 0.1 mg mL−1. Pyocyanin biosynthesis decreases until 64% (0.1–4 mg mL−1) for both strains. Swarming motility of P. aeruginosa ATCC 27853 was completely inhibited by 2 mg mL−1 of lemon oils. Furthermore, a decrease (29–55%, 0.1–4 mg mL−1) in the synthesis of Quorum sensing (QS) signals was observed. The oils showed higher biological activities than limonene. Hence, their ability to control the biofilm of P. aeruginosa and reduce the production of virulence factors regulated by QS makes lemon oils good candidates to be applied as preservatives in the food processing industry.Fil: Luciardi, María Constanza. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Blázquez, María Amparo. Universidad de Valencia; EspañaFil: Alberto, Maria Rosa. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Cartagena, Elena. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin

Volatile Terpenoids from Water Pepper (Polygonum punctatum) Against Pseudomonas aeruginosa and Staphylococcus aureus Virulence Strategies

Polygonum punctatum Elliot (water pepper) is a pungent herb ancestrally employed as a disinfectant in traditional medicine by Toba Indians of the north-eastern region of Argentina and also commonly used as spice in Japanese cuisine. GC-MS of whole diethyl ether extract (EE) from aerial parts allowed to identify 14 volatile terpenoids such as sesquiterpenes: α-bisabolol (3.4 %), polygodial and isotadeonal (34.0%); various methylated phenol like α- tocopherol or vitamin E (3.6 %), and phytosterols: stigmasterol (2.1%) and β-sitosterol (29.9 %). Thus, water pepper is a promising source of drimane sesquiterpenes and phytoestrogens with important bioactivities. Following a taste- guided fractionation by CC and HPLC, drimane-type sesquiterpenes, polygodial (1) and its stereoisomer isotadeonal (2) were isolated as main compounds from the EE. The antipathogenic effects on the bacterial growth, biofilm formation, and elastase activity of both pure compounds and EE were evaluated against two Staphylococcus aureus and two Pseudomonas aeruginosa strains at 10 and 100 µg/mL. The highest effects were observed for the non pungent drimane isotadeonal (2) which was able to reduce about 75 % the bacterial growth of all tested microorganisms and to inhibit Gram-positive biofilm formation (85 % mean) at 100 µg/mL. In addition, elastase activity of P. aeruginosa, another virulence strategy, was attenuated more than 50 % at 100 µg/mL by 2. These results provide evidence that support the antimicrobial use of P. punctatum against P. aeruginosa and S. aureus, as well as, demonstrating that isotadeonal (2), despite it has been suggested to lack biological properties, is a bioactive compound able to control biofilm formation and bacterial growth of both human pathogens.Fil: Gilabert Valero, José Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Cartagena, Elena. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Escobar, Gabriela. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

Wine-making wastes as biofilm inhibitors of Staphylococcus aureus

Staphylococcus aureus es un patógeno conocido que forma biopelículas en una amplia variedad de entornos y representa un riesgo severo de contaminación de los alimentos. El presente estudio se centró en la determinación de las capacidades antibiofilm de extractos de orujo procedentes de diferentes varietales de diferentes polaridades, procedentes de Cafayate, Argentina, frente a dos cepas de S. aureus. Se utilizaron orujos de tres varietales regionales (Bonarda, Tannat y Malbec) para inhibir la formación de biofilm (BF) o tratar una biopelícula formada. Se realizaron extracciones con solventes de polaridad creciente (cloroformo, acetato de etilo y etanol) y se enfrentaron 10 y 100 μg/mL de extractos a las cepas de S. aureus ATCC 6538 y LVP63. Los extractos acetato de etilo y etanólicos de orujo del varietal Tannat fueron los más efectivos para disminuir la formación de BF en S. aureus sin afectar al crecimiento planctónico. Respecto a los efectos sobre la biopelícula preformada, los extractos de los varietales Malbec y Tannat disminuyeron la actividad metabólica hasta un 70 % y los extractos polares de Tannat y la mezcla de orujos disgregaron hasta un 65 % el BF preformado por ambas cepas S. aureus. Por lo tanto, la reutilización de estos desechos agroindustriales se plantea como una alternativa natural para combatir bacterias patógenas en la industria alimentaria, disminuyendo el impacto de estos residuos agroindustriales en el ambiente y convirtiendo a estos desechos en un bioproducto, económicamente, rentable.Staphylococcus aureus is a well-known pathogen living as biofilm in a wide variety of environments and represents a severe risk of food contamination. The present study focused on the antibiofilm capacity of pomace extracts of different polarities and different varietals against two strains of S. aureus. Wine pomace of three varietals (Bonarda, Tannat, and Malbec) from Cafa-yate, Argentine, at two concentrations (10 and 100 μg/mL) was used to inhibit biofilm formation(BF) and preformed biofilm of S. aureus ATCC 6538 and LVP63 strains. Extractions were ca-rried out with solvents of increasing polarity (chloroform, ethyl acetate, and ethanol). The ethyl acetate and ethanolic pomace extracts of the Tannat varietal were the most effective in reducing the BF formation in S. aureus without affecting planktonic growth. The extracts of Malbec and Tannat diminish the biofilm metabolic activity up to 70 %. Likewise, the polar Tannat extracts and the mixture pomace disrupt the preformed BF in both S. aureus strains.These residues can be used as a natural alternative source for the inhibition of pathogenic bacteria in the food industry and reduce the impact of these agro-industrial wastes on the environment.Ciencias Experimentale

Wine-making wastes as biofilm inhibitors of Staphylococcus aureus

Staphylococcus aureus es un patógeno conocido que forma biopelículas en una amplia variedadde entornos y representa un riesgo severo de contaminación de los alimentos. El presente estudiose centró en la determinación de las capacidades antibiofilm de extractos de orujo procedentesde diferentes varietales de diferentes polaridades, procedentes de Cafayate, Argentina, frentea dos cepas de S. aureus. Se utilizaron orujos de tres varietales regionales (Bonarda, Tannat yMalbec) para inhibir la formación de biofilm (BF) o tratar una biopelícula formada. Se realizaron extracciones con solventes de polaridad creciente (cloroformo, acetato de etilo y etanol)y se enfrentaron 10 y 100 μg/mL de extractos a las cepas de S. aureus ATCC 6538 y LVP63.Los extractos acetato de etilo y etanólicos de orujo del varietal Tannat fueron los más efectivospara disminuir la formación de BF en S. aureus sin afectar al crecimiento planctónico. Respectoa los efectos sobre la biopelícula preformada, los extractos de los varietales Malbec y Tannatdisminuyeron la actividad metabólica hasta un 70 % y los extractos polares de Tannat y la mezcla de orujos disgregaron hasta un 65 % el BF preformado por ambas cepas S. aureus. Por lotanto, la reutilización de estos desechos agroindustriales se plantea como una alternativa naturalpara combatir bacterias patógenas en la industria alimentaria, disminuyendo el impacto de estosresiduos agroindustriales en el ambiente y convirtiendo a estos desechos en un bioproducto,económicamente, rentable.Staphylococcus aureus is a well-known pathogen living as biofilm in a wide variety of envi-ronments and represents a severe risk of food contamination. The present study focused on the antibiofilm capacity of pomace extracts of different polarities and different varietals against two strains of S. aureus. Wine pomace of three varietals (Bonarda, Tannat, and Malbec) from Cafa-yate, Argentine, at two concentrations (10 and 100 μg/mL) was used to inhibit biofilm formation (BF) and preformed biofilm of S. aureus ATCC 6538 and LVP63 strains. Extractions were ca-rried out with solvents of increasing polarity (chloroform, ethyl acetate, and ethanol). The ethyl acetate and ethanolic pomace extracts of the Tannat varietal were the most effective in reducing the BF formation in S. aureus without affecting planktonic growth. The extracts of Malbec and Tannat diminish the biofilm metabolic activity up to 70 %. Likewise, the polar Tannat extracts and the mixture pomace disrupt the preformed BF in both S. aureus strains.These residues can be used as a natural alternative source for the inhibition of pathogenic bacte-ria in the food industry and reduce the impact of these agro-industrial wastes on the environment.Fil: Viola, Carolina Maria. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; ArgentinaFil: Cartagena, Elena. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin

Insecticidal activities of diketopiperazines of Nomuraea rileyi entomopathogenic fungus

Entomopathogenic fungi are fungal organisms extensively used in various parts of the world as biopesticides against insect pests that cause important economic damage. Various secondary metabolites produced by these fungi have many potential biological activities. The present study was undertaken to evaluate the insecticidal activity of extracts and pure compounds from Nomuraea rileyi (Farlow) Samson entomopathogenic fungi against Spodoptera frugiperda Smith (Lepidoptera), Ceratitis capitata Wiedemann (Diptera) and Tribolium castaneum Herbst (Coleoptera), three insect pests that generate serious economic losses in the northwest of Argentina. Diketopiperazines were extracted from the culture free supernatant of the media with ethyl acetate. Antifeedant properties were detected in all extracts under dietary choice conditions (300 ug/ g of diet). The maximum antifeedant activity was noted in cycles (Pro-Val) (86.02) and cycle (Pro-Phe) (73.47), while the rest of the extracts and metabolites exhibited varying degrees of moderate or less toxic effects. The maximum oviposition deterrence against C. capitata (55.86%) was recorded with cycle (Pro-Phe) at a 50 µm/cm2 dose. Culture medium extracts supplemented with insect remains and all pure compounds showed repellent action against T. castaneum. The main repellency was observed in phenylacetic acid and cycle (Pro-Val) with RI values of 42 and 41% respectively. The present study would suggest the possible utilization of entomopathogenic fungal metabolites as an effective agent for controlling insect pests that cause important economic losses

Combined Endoscopic Stent-In-Stent Placement by Lumen-Apposing Metal Stents Through Self-Expanding Metal Stents for Simultaneous Malignant Biliary and Duodenal Obstruction

The palliation of simultaneous biliary and duodenal obstruction in patients with advanced pancreatic cancer is a clinically and technically challenging scenario. Endoscopic procedures are a valid alternative to surgical or percutaneous transhepatic biliary drainage. The availability of self-expanding metal stents (SEMSs) and lumen-apposing metal stents (LAMS) have expanded therapeutic options. We describe a case in which biliary and duodenal obstructions were treated successfully with the combined use of SEMS and LAMS devices. Endoscopic ultrasound-guided biliary drainage with the use of new LAMS and a duodenal SEMS can be a valid option in expert hands as a palliative and minimally invasive treatment for gastric outlet and biliary obstruction

Causas de re internaciones de pacientes oncológicos pediátricos

El cáncer infantil constituye un grupo heterogéneo de enfermedades con etiología, tratamiento y pronóstico diferente. El diagnóstico de cáncer puede adquirir un significado especial, en muchas ocasiones es el enfrentamiento con una muerte inminente. De hecho, el cáncer sigue siendo la segunda causa de muerte en la infancia, en los países en desarrollo, después de los accidentes. El diagnóstico y tratamiento rápido y adecuado intentan no sólo curar al paciente, sino que las secuelas físicas y psicológicas sean las mínimas posibles. La responsabilidad en la detección precoz de estas enfermedades reside en el pediatra de cabecera y los individuos cercanos al enfermo; sin embargo, su supervivencia y su calidad de vida dependen, en la gran mayoría de casos, del manejo adecuado y cuidadoso por parte de un conjunto complejo de especialistas, coordinados por el oncólogo. El cuidado de un niño debe orientarse hacia la atención integral del paciente y a la familia, es por ello que los profesionales deben tener los conocimientos sobre el manejo durante el diagnóstico y tratamiento, que acompañen y que pueda adelantarse ante posibles riesgos que pueden llevarlo a una reinternación. Múltiples son las causas que pueden incidir en la reinternación de los niños con patologías crónicas como el cáncer, las cuales estén relacionadas a la propia enfermedad, a su entorno social y cultural. Este trabajo de investigación tiene como objetivo determinar cuáles son las causas de re internaciones en pacientes pediátricos con cáncer del SIP 5, en el periodo abril, mayo, junio y julio del año 2018 en el Hospital Humberto Notti. La investigación es de naturaleza cuantitativa, descriptiva, de corte transversal, de fuente primaria y de campo.Fil: Arena, Natalia Irene.Fil: Aguirre, María Elena.Fil: Trujillo, Mariela Noemí