Study of the Nature and Location of Silver in Ag-Exchanged Mordenite Catalysts. Characterization by Spectroscopic Techniques

 Catalysts based on Na-mordenite (symbolized as M) exchanged with 5, 10, and 15 wt % of Ag were characterized by X-ray photoelectron spectroscopy (XPS), extended X-ray absorption fine line structure (EXAFS), X-ray absorption near edge spectroscopy (XANES) and UV-vis diffuse reflectance spectroscopy (DRS) to investigate the effect of different treatments on the chemical state and surface concentration of the silver species. The AgxM catalysts were analyzed in oxidizing (O2) or reducing (H2/Ar) atmospheres and also after being used in the selective catalytic reduction of NOx or in successive cycles of toluene adsorption/desorption. In calcined samples, EXAFS profiles showed two types of AgO spheres of coordination, one due to a dispersed phase of silver oxide and the other due to Ag+ ions in interaction with the oxygen of the zeolite framework. The UV-vis DRS spectra showed the coexistence of isolated Ag+, Agn(delta)+ (n < 10) cationic clusters and AgxO particles. In addition, through the modified Auger parameter (alpha), calculated from XPS measurements, it was possible to identify Ag+ ions at exchange sites (alpha = 722 eV) and AgxO ( alpha = 725 eV) highly dispersed on the surface. Both species constitute stable active centers for the selective catalytic reduction of NOx under severe reaction conditions. However, during the adsorption-desorption of toluene, the reduction of silver oxides produces Ag(0) due to thermal hydrocarbon decomposition.   Fil: Aspromonte, Soledad Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina. Universidad Nacional del Litoral; ArgentinaFil: Mizrahi, Martin Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Schneeberger, Florencia A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; ArgentinaFil: Ramallo Lopez, Jose Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Boix, Alicia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina. Universidad Nacional del Litoral; Argentin

Study X-ray photoelectron spectroscopy determination of interactions between gold nanoparticles and epidermal growth factor for potential use in biomedicine

Nowadays, biomedical applications of gold nanoparticles coupled with Epidermal Growth Factor have attracted huge attention because of its theranostic activity, which could be useful for diagnosis and treatment of neurodegenerative diseases. Therefore, there is a great interest to know the nature of the intermolecular interactions between the gold nanoparticles and epidermal growth factor (EGF). A two-step synthesis was performed. In the first step, gold nanoparticles were synthesized by chemical reduction of tetrachloroauric acid using sodium citrate as reducing and capping agent. Secondly, gold nanoparticles were coupled with EGF. The obtained nanoparticles were characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and zeta-potential before and after being coupled with the EGF. Gold nanoparticles with an average diameter of 8.09 nm were obtained. After coupled with EGF, the particle average diameter increased to 9.14 nm. X-ray photoelectron spectroscopy showed an electrostatic interaction between gold nanoparticles and EGF. Zeta potential corroborated these results. Thus, it was possible for the first time to identify the interactions between these two chemical species. Since gold nanoparticles may act as carriers of EGF, these results illustrate the great potential for the use of this bionanocomposite in neurodegenerative disease treatment.UAEME

Primer registro de la plaga exótica Sitona discoideus Gyllenhal 1834 (Coleoptera: Curculionidae) en Argentina

El gorgojo de la raíz de la alfalfa, Sitona discoideus Gyllenhal 1834 (Curculionidae: Entiminae), es reportado por primera vez en la Argentina. Este gorgojo es nativo del sur de Europa y noreste de África, y fue introducido accidentalmente en Australia, Nueva Zelanda, Estados Unidos y Chile. En Argentina fue colectado en el Alto valle de Río Negro, asociado con plantas de alfalfa (Medicago sativa L.).The alfalfa root weevil Sitona discoideus Gyllenhal 1834 (Curculionidae:Entiminae) is herein reported for the first time for Argentina. This weevil is native to southern Europe and northern Africa and was accidentally introduced in Australia, New Zealand, the United States of America, and Chile. In Argentina, it was collected in the Upper valley of Río Negro, associated with alfalfa plants (Medicago sativa L.).Fil: del Rio, Maria Guadalupe. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Lanteri, Analia Alicia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Gittins López, Cecilia Gabriela. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Instituto de Investigación y Desarrollo Tecnológico para la Agricultura Familiar Región Patagonia; ArgentinaFil: Rivero, Victoria Ileana. Universidad Nacional del Comahue. Facultad de Ciencias Agrarias; ArgentinaFil: González, Diego A.. Universidad Nacional del Comahue. Facultad de Ciencias Agrarias; ArgentinaFil: Lopez Armengol, Maria Fernanda. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Instituto de Investigación y Desarrollo Tecnológico para la Agricultura Familiar Región Patagonia; Argentina. Universidad Nacional del Comahue. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Confluencia; Argentin

Clonal micropropagation and ex-situ conservation of Rhyncholaelia digbyana (Lindley) Schltr

Objective: To obtain protocols for clonal micropropagation, crop planning, and in vitro conservation of Rhycholaelia digbyana (Lindley) Schltr. Methodology: The effects of the Kundson C basal medium and benzylaminopurine concentration were evaluated for clonal micropropagation. The treatment with the greatest number of shoots formed per apex was selected for crop planning. Experiments were conducted to determine the effect of basal medium Murashige and Skoog concentration at 2.2 gL-1 and 4.4 gL-1; sorbitol, mannitol, and sucrose at 1, 2, and 3% on slow growth. Results: The best treatment for clonal micropropagation and crop planning was identified as 21.60 gL-1 Knudson C with 8.80 µM benzylaminopurine. This treatment resulted in uniform-sized shoots produced. The multiplication process can yield 10,240 seedlings in 12 months. Slow growth was achieved using Murashige and Skoog basal media at 2.2 gL-1 with 1% mannitol. Implications: More experiments must be conducted to determine the best shoot induction conditions and improve resource efficiency. Conclusions: These findings represent the first report on micropropagation and ex-situ conservation to preserve germplasm for this species as an important resource for the floriculture industry. &nbsp;Objective: To obtain protocols for clonal micropropagation, crop planning, and in vitro conservation of Rhycholaelia digbyana (Lindley) Schltr. Methodology: The effects of the Kundson C basal medium and benzylaminopurine concentration were evaluated for clonal micropropagation. The treatment with the greatest number of shoots formed per apex was selected for crop planning. Experiments were conducted to determine the effect of basal medium Murashige and Skoog concentration at 2.2 gL-1 and 4.4 gL-1; sorbitol, mannitol, and sucrose at 1, 2, and 3% on slow growth. Results: The best treatment for clonal micropropagation and crop planning was identified as 21.60 gL-1 Knudson C with 8.80 µM benzylaminopurine. This treatment resulted in uniform-sized shoots produced. The multiplication process can yield 10,240 seedlings in 12 months. Slow growth was achieved using Murashige and Skoog basal media at 2.2 gL-1 with 1% mannitol. Implications: More experiments must be conducted to determine the best shoot induction conditions and improve resource efficiency. Conclusions: These findings represent the first report on micropropagation and ex-situ conservation to preserve germplasm for this species as an important resource for the floriculture industry

The Extrusion Process as an Alternative for Improving the Biological Potential of Sorghum Bran: Phenolic Compounds and Antiradical and Anti-Inflammatory Capacity

Approximately 80% of sorghum phenolic compounds are linked to arabinoxylans by ester bonds, which are capable of resisting the digestion process in the upper gastrointestinal tract, compromising their bioaccessibility and biological potential. The aim of this study was to evaluate the effect of the extrusion process on the content of phenolic compounds in sorghum bran and its impact on phenolic compounds and antiradical and anti-inflammatory capacity. Results revealed that the extrusion process increased total phenol content in sorghum bran compared to nonextruded sorghum, particularly for extrusion at 180°C with 20% moisture content (2.0222±0.0157 versus 3.0729±0.0187 mg GAE/g +52%), which positively affected antiradical capacity measured by the DPPH and TEAC assays. The percentage of inhibition of nitric oxide (NO) production by RAW cells due to the presence of extruded sorghum bran extract was significantly higher than that of nonextruded sorghum bran extract (90.2±1.9% versus 76.2±1.3%). The results suggest that extruded sorghum bran could be used as a functional ingredient and provide advantages to consumers by reducing diseases related to oxidative stress and inflammation

Inventory of some families of Hemiptera, Coleoptera (Curculionidae) and Hymenoptera associated with horticultural production of the Alto Valle de Río Negro and Neuquén provinces (Argentina)

The knowledge of the entomological fauna in productive systems is important for the agroecological management since beneficial insects are a key resource for pest management in horticultural systems. Scientific information on the biodiversity present in a given area is essential as well as the ecological function and/or feeding habits of the insects. In Alto Valle de Río Negro and Neuquén, horticultural production systems can be described as highly dependent on chemical inputs for pest management and fertilization. The aim of this study is to carry out an inventory of the biodiversity of some families of Hemiptera, Coleoptera (Curculionidae) and Hymenoptera present in peri-urban and rural farms located in Neuquén and Río Negro, respectively. Insects were collected through pitfall and sweeping net on tomato and pepper crops and the surrounding non-cultivated areas. Idiosystatus Berg (Auchenorrhyncha) was cited for the first time from Argentina. Species cited for the first time from Neuquén: Hemiptera: Auchenorrhyncha: Acanalonia chloris (Berg), Syncharina punctatissima (Signoret), Amplicephalus dubius Linnavuori, Exitianus obscurinervis (Stål), Agalliana ensigera Oman and Bergallia signata (Stål); Hemiptera: Heteroptera: Harmostes (Harmostes) prolixus Stål and Atrachelus (Atrachelus) cinereus (Fabricius); Coleoptera: Curculionidae: Hypurus bertrandi (Perris), Naupactus leucoloma Boheman, Otiorhynchus rugosostriatus (Goeze) and Sitona discoideus Gyllenhal and Hymenoptera: Xylocopa (Neoxylocopa) augusti Lepeletier and Pseudagapostemon (Neagapostemon) singularis Jörgensen. Species cited for the first time from Río Negro: Hemiptera: Auchenorrhyncha: Amplicephalus dubius Linnavuori, Amplicephalus marginellanus Linnavuori, Circulifer tenellus (Baker) and Xerophloea viridis (Fabricius); Hemiptera: Heteroptera: Tupiocoris cucurbitaceus (Spinola), Atrachelus (Atrachelus) cinereus (Fabricius), Dichelops furcatus (Fabricius) and Harmostes (Harmostes) prolixus Stål; Coleptera: Curculionidae: Naupactus xanthographus (Germar) and Hymenoptera: Diadasia pereyrae (Holmberg) and Dialictus autranellus (Vachal).El conocimiento de la fauna entomológica presente en los sistemas productivos es importante para el manejo agroecológico ya que los insectos beneficiosos son un recurso clave para el manejo de plagas en los sistemas hortícolas. Es esencial contar con información científica sobre la biodiversidad presente en un área determinada y la función ecológica y/o los hábitos alimenticios de los insectos. En el Alto Valle de Río Negro y Neuquén, los sistemas de producción hortícola pueden describirse como altamente dependientes de los insumos químicos para el manejo de plagas y fertilización. El objetivo de este estudio es realizar un inventario de la biodiversidad de algunas familias de Hemiptera, Coleoptera (Curculionidae) e Hymenoptera presentes en las chacras periurbanas y rurales ubicadas en Neuquén y Río Negro, respectivamente. Los insectos fueron recolectados a través de trampas de caída y red entomológica en cultivos de tomate y pimiento, y áreas circundantes no cultivadas. Idiosystatus Berg (Auchenorrhyncha) fue citado por primera vez en Argentina. Especies citadas por primera vez en Neuquén: Hemiptera: Auchenorrhyncha: Acanalonia chloris (Berg), Syncharina punctatissima (Signoret), Amplicephalus dubius Linnavuori, Exitianus obscurinervis (Stål), Agalliana ensigera Oman y Bergallia signata (Stål); Hemiptera: Heteroptera: Harmostes (Harmostes) prolixus Stål y Atrachelus (Atrachelus) cinereus (Fabricius); Coleoptera: (Curculionidae): Hypurus bertrandi (Perris), Naupactus leucoloma Boheman, Otiorhynchus rugosostriatus (Goeze) y Sitona discoideus Gyllenhal e Hymenoptera: Xylocopa (Neoxylocopa) augusti Lepeletier and Pseudagapostemon (Neagapostemon) singularis Jörgensen. Especies citadas por primera vez en Río Negro: Hemiptera: Auchenorrhyncha: Amplicephalus dubius Linnavuori, Amplicephalus marginellanus Linnavuori, Circulifer tenellus (Baker) y Xerophloea viridis (Fabricius); Hemiptera: Heteroptera: Tupiocoris cucurbitaceus (Spinola), Atrachelus (Atrachelus) cinereus (Fabricius), Dichelops furcatus (Fabricius) y Harmostes (Harmostes) prolixus Stål; Coleoptera: Curculionidae: Naupactus xanthographus (Germar) e Hymenoptera: Diadasia pereyrae (Holmberg) y Dialictus autranellus (Vachal).Área Investigación y Desarrollo Tecn. Agricultura Familiar - Región PatagoniaFil: Alvarez, Leopoldo Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Bernardis, Adela M. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud; ArgentinaFil: Defea, Bárbara Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Dellapé, Pablo Matías. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil. Del Río, Maria Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Gittins Lopez, Cecilia Gabriela. Instituto Nacional Tecnología Agropecuaria (INTA). Área Investigación y Desarrollo Tecn. Agricultura Familiar - Región Patagonia; ArgentinaFil: Lanteri, Analía A. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: López Armengol, María Fernanda. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud; Argentina. Instituto Nacional Tecnología Agropecuaria (INTA). Área Investigación y Desarrollo Tecn. Agricultura Familiar - Región Patagonia; ArgentinaFil: Marino de Remes Lenicov, Ana María. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Minghetti, Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Paradell, Susana Liria. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC PBA); ArgentinaFil: Rizzo, Maria Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Telemedicine Enables Broader Access to Movement Disorders Curricula for Medical Students

Background: The impact of tele-education for movement disorders on medical students is unknown. The present study had three objectives. First, to create a tele-education program for medical students in regions with limited access to movement disorders curricula. Second, to analyze the feasibility, satisfaction, and improvement of medical knowledge. Third, to assess the main reasons of medical students for attending this course. Methods: In 2016, a program was piloted in a low-middle income (Cameroon) and a middle-high income (Argentina) country. Medical students were offered a free movement disorder tele-education program (four medical schools in Argentina, and 1 medical school in Cameroon). Six real-time videoconferences covering hyperkinetic and hypokinetic movement disorders were included. Evaluations included attendance, pre- and post-medical knowledge, and satisfaction questionnaires. Results: The study included 151 undergraduate medical students (79.4% from Argentina, 20.6% from Cameroon). Feasibility was acceptable with 100% and 85.7% of the videoconferences completed in Argentina and Cameroon, respectively. Attendance was higher in Argentina compared to Cameroon (75% vs. 33.1%). According to student reports, the topics and innovative educational environment were the main reasons for attendance. Both groups ranked satisfaction as moderate to high, and medical knowledge improved similarly in both countries. Discussion: Tele-education can improve movement disorders knowledge in medical schools in high-middle and low-middle income countries lacking access to other educational opportunities

Epidemiology of giardiasis and assemblages A and B and effects on diarrhea and growth trajectories during the first 8 years of life: Analysis of a birth cohort in a rural district in tropical Ecuador.

BACKGROUND: There are limited longitudinal data on the acquisition of Giardia lamblia infections in childhood using molecular assays to detect and type assemblages, and measure effects of infections on diarrhea risk and childhood growth. METHODS: We analysed stool samples from a surveillance sample within a birth cohort in a rural district in tropical Ecuador. The cohort was followed to 8 years of age for the presence of G. lamblia in stools by quantitative PCR and A and B assemblages by Taqman assay or Sanger sequencing. We explored risk factors associated with infection using generalized estimating equations applied to longitudinal binary outcomes, and longitudinal panel data analysis to estimate effects of infection on diarrhea and growth trajectories. RESULTS: 2,812 stool samples collected between 1 month and 8 years of age from 498 children were analyzed and showed high rates of infection: 79.7% were infected at least once with peak prevalence (53.9%) at 5 years. Assemblage B was accounted for 56.8% of genotyped infections. Risk factors for infection included male sex (P = 0.001), daycare attendance (P<0.001), having a household latrine (P = 0.04), childhood (P<0.001) and maternal soil-transmitted helminth (P = 0.029) infections, and exposures to donkeys (age interaction P = 0.034). G. lamblia was associated with increased risk of diarrhea (per episode, RR 1.03, 95% CI 1.01-1.06, P = 0.011) during the first 3 years of life and a transient impairment of weight (age interaction P = 0.017) and height-for-age (age interaction P = 0.025) trajectories between 1 and 4 years of age. There was no increased risk of either assemblage being associated with outcomes. CONCLUSION: Our data show a relatively high edemicity of G. lamblia transmission during childhood in coastal Ecuador, and evidence that infection is associated with a transiently increased risk of diarrhea during the first 3 years of life and impairment of weight and height between 1 and 4 years

Correction: Lack of Mucosal Immune Reconstitution during Prolonged Treatment of Acute and Early HIV-1 Infection

BACKGROUND: During acute and early HIV-1 infection (AEI), up to 60% of CD4(+) T cells in the lamina propria of the lower gastrointestinal (GI) tract are lost as early as 2–4 wk after infection. Reconstitution in the peripheral blood during therapy with highly active antiretroviral therapy (HAART) is well established. However, the extent of immune reconstitution in the GI tract is unknown. METHODS AND FINDINGS: Fifty-four AEI patients and 18 uninfected control participants underwent colonic biopsy. Forty of the 54 AEI patients were followed after initiation of antiretroviral therapy (18 were studied longitudinally with sequential biopsies over a 3-y period after beginning HAART, and 22 were studied cross sectionally after 1–7 y of uninterrupted therapy). Lymphocyte subsets, markers of immune activation and memory in the peripheral blood and GI tract were determined by flow cytometry and immunohistochemistry. In situ hybridization was performed in order to identify persistent HIV-1 RNA expression. Of the patients studied, 70% maintained, on average, a 50%–60% depletion of lamina propria lymphocytes despite 1–7 y of HAART. Lymphocytes expressing CCR5 and both CCR5 and CXCR4 were persistently and preferentially depleted. Levels of immune activation in the memory cell population, CD45RO(+) HLA-DR(+), returned to levels seen in the uninfected control participants in the peripheral blood, but were elevated in the GI tract of patients with persistent CD4(+) T cell depletion despite therapy. Rare HIV-1 RNA–expressing cells were detected by in situ hybridization. CONCLUSIONS: Apparently suppressive treatment with HAART during acute and early infection does not lead to complete immune reconstitution in the GI mucosa in the majority of patients studied, despite immune reconstitution in the peripheral blood. Though the mechanism remains obscure, the data suggest that there is either viral or immune-mediated accelerated T cell destruction or, possibly, alterations in T cell homing to the GI tract. Although clinically silent over the short term, the long-term consequences of the persistence of this lesion may emerge as the HIV-1–infected population survives longer owing to the benefits of HAART