236 research outputs found

    Valence and inner electronic excitation, ionization, and fragmentation of perfluoropropionic acid

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    The photoexcitation, photoionization, and photofragmentation of gaseous CF3CF2C(O)OH were studied by means of synchrotron radiation in the valence and inner energy regions. Photofragmentation events were detected from 11.7 eV through formation of COH+, C2F4+, and the parent species M+. Because the vertical ionization potential has been reported at 11.94 eV, the starting energy used in this study, 11.7 eV, falls just inside of the tail of the ionization band in the photoelectron spectra. Information from the total ion yield spectra around the C 1s, O 1s, and F 1s ionization potentials allows the energies at which different resonance transitions take place in the molecule to be determined. These transitions have been assigned by comparison with the results of the analysis of similar compounds. In the inner energy region, both kinetic energy release (KER) values and the slope and shape of double coincidence islands obtained from photoelectron–photoion–photoion coincidence (PEPIPICO) spectra allow different photofragmentation mechanisms to be elucidated.Centro de Química Inorgánic

    Smoking Patterns and Receipt of Cessation Services Among Pregnant Women in Argentina and Uruguay

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    Introduction: The 5A’s (Ask, Advise, Assess, Assist, and Arrange) strategy, a best-practice approach for cessation counseling, has been widely implemented in high-income countries for pregnant women; however, no studies have evaluated implementation in middle-income countries. The study objectives were to assess smoking patterns and receipt of 5A’s among pregnant women in Buenos Aires, Argentina and Montevideo, Uruguay. Methods: Data were collected through administered questionnaires to women at delivery hospitalizations during October 2011–May 2012. Eligible women attended one of 12 maternity hospitals or 21 associated prenatal care clinics. The questionnaire included demographic data, tobacco use/cessation behaviors, and receipt of the 5A’s. Self-reported cessation was verified with saliva cotinine. Results: Overall, of 3400 pregnant women, 32.8% smoked at the beginning of pregnancy; 11.9% quit upon learning they were pregnant or later during pregnancy, and 20.9% smoked throughout pregnancy. Smoking prevalence varied by country with 16.1% and 26.7% who smoked throughout pregnancy in Argentina and Uruguay, respectively. Among pregnant smokers in Argentina, 23.8% reported that a provider asked them about smoking at more than one prenatal care visit; 18.5% were advised to quit; 5.3% were assessed for readiness to quit, 4.7% were provided assistance, and 0.7% reported follow-up was arranged. In Uruguay, those percentages were 36.3%, 27.9%, 5.4%, 5.6%, and 0.2%, respectively. Conclusions: Approximately, one in six pregnant women smoked throughout pregnancy in Buenos Aires and one in four in Montevideo. However, a low percentage of smokers received any cessation assistance in both countries. Healthcare providers are not fully implementing the recommended 5A’s intervention to help pregnant women quit smoking.Fil: Berrueta, Amanda Mabel. Instituto de Efectividad ClĂ­nica y Sanitaria; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Morello, Paola. Instituto de Efectividad ClĂ­nica y Sanitaria; ArgentinaFil: AlemĂĄn, Alicia. Unidad de InvestigaciĂłn ClĂ­nica y EpidemiolĂłgica Montevideo; UruguayFil: Tong, Van T.. Centers for Disease Control and Prevention; Estados UnidosFil: Johnson, Carolyn. Tulane School of Public Health and Tropical Medicine; Estados UnidosFil: Dietz, Patricia M.. Centers for Disease Control and Prevention; Estados UnidosFil: Farr, Sherry L.. Centers for Disease Control and Prevention; Estados UnidosFil: Mazzoni, Agustina. Instituto de Efectividad ClĂ­nica y Sanitaria; ArgentinaFil: Colomar, Mercedes. Unidad de InvestigaciĂłn ClĂ­nica y EpidemiolĂłgica Montevideo; UruguayFil: Ciganda, Alvaro. Unidad de InvestigaciĂłn ClĂ­nica y EpidemiolĂłgica Montevideo; UruguayFil: Llambi, Laura. Unidad de InvestigaciĂłn ClĂ­nica y EpidemiolĂłgica Montevideo; UruguayFil: BecĂș, Ana. Instituto de Efectividad ClĂ­nica y Sanitaria; ArgentinaFil: Gibbons, Luz. Instituto de Efectividad ClĂ­nica y Sanitaria; ArgentinaFil: Smith, Ruben A.. Centers for Disease Control and Prevention; Estados UnidosFil: Buekens, Pierre. Tulane School of Public Health and Tropical Medicine; Estados UnidosFil: Belizan, Jose. Instituto de Efectividad ClĂ­nica y Sanitaria; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Althabe, Fernando. Instituto de Efectividad ClĂ­nica y Sanitaria; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentin

    A Liposomal Formulation to Exploit the Bioactive Potential of an Extract from Graciano Grape Pomace

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    Antioxidant compounds with health benefits can be found in food processing residues, such as grape pomace. In this study, antioxidants were identified and quantified in an extract obtained from Graciano red grape pomace via a green process. The antioxidant activity of the extract was assessed by the DPPH and FRAP tests, and the phenolic content by the Folin–Ciocalteu test. Furthermore, nanotechnologies were employed to produce a safe and effective formulation that would exploit the antioxidant potential of the extract for skin applications. Anthocyanins, flavan-3-ols and flavanols were the main constituents of the grape pomace extract. Phospholipid vesicles, namely liposomes, were prepared and characterized. Cryo-TEM images showed that the extract-loaded liposomes were predominantly spherical/elongated, small, unilamellar vesicles. Light scattering results revealed that the liposomes were small (~100 nm), homogeneously dispersed, and stable during storage. The non-toxicity of the liposomal formulation was demonstrated in vitro in skin cells, suggesting its possible safe use. These findings indicate that an extract with antioxidant properties can be obtained from food processing residues, and a liposomal formulation can be developed to exploit its bioactive value, resulting in a promising healthy product

    High prevalence of secondary resistance mutations in Venezuelan HIV-1 isolates.

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    The genetic variability was studied in HIV-1 from Venezuelan patients with and without treatment, in order to evaluate the presence of polymorphisms and drug resistance mutations. Proviral DNA from peripheral blood mononuclear cells or viral RNA from plasma was extracted from the blood of 30 patients. Two regions from the polymerase gene, protease (Pr) and reverse transcriptase (RT) and one genomic fragment from the envelope (Env) gene were amplified and sequenced. All HIV-1 samples analyzed were classified as subtype B, without evidence of recombination. Although no primary protease mutations were detected, a high frequency of secondary mutations (86%, 19/22), associated to restoration of viral replicative fitness, was observed in strains circulating both in treated and non-treated patients. Resistance mutations to nucleoside RT inhibitors (NRTI) and non-nucleoside RT inhibitors (NNRTI) were detected in 35% (6/17) and 12% (2/17) of the viruses circulating in treated patients, respectively. Resistance mutations were also present in the virus infecting one antiretroviral naive individual (7.7%), suggesting that local screening for resistant mutation in naive patient might be important to minimize therapy failure. Future studies are warranted to assess the role of secondary mutation in the success of viral infection

    Anticorpos muscarĂ­nicos e resposta da frequĂȘncia cardĂ­aca ao exercĂ­cio dinĂąmico e a manobra de Valsalva na doença de Chagas crĂŽnica

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    We have studied the cardiac chronotropic responses to the Valsalva maneuver and to dynamic exercise of twenty chronic chagasic patients with normal left ventricular function and no segmental wall abnormalities by two-dimensional echocardiogram. The absolute increase in heart rate of the patients (Δ = 21.5 ± 10 bpm, M±SD) during the maneuver was significantly diminished when compared to controls (Δ = 31.30 ± 70, M±SD, p = 0.03). The minimum heart rate (58.24 ± 8.90 vs. 62.80 ± 10, p = 0.68) and the absolute decrease in heart rate at the end of the maneuver (Δ = 38.30 ± 13 vs. Δ = 31.47 ± 17, p = 0.10) were not different from controls. The initial heart rate acceleration during dynamic exercise (Δ = 12 ± 7.55 vs. Δ = 19 ± 7.27, M±SD, p = 0.01) was also diminished, but the heart rate recovery during the first ten seconds was more prominent in the sero-positive patients (Median: 14, Interquartile range: (9.75-17.50 vs. 5(0-8.75, p = 0.001). The serum levels of muscarinic cardiac auto-antibodies were significantly higher in the chagasic patients (Median: 34.58, Interquartile Range: 17-46.5, Optical Density) than in controls (Median: 0, Interquartile Range: 0-22.25, p = 0.001) and correlated significantly and directly (r = 0.68, p = 0.002) with early heart rate recovery during dynamic exercise. The results of this investigation indirectly suggest that, the cardiac muscarinic auto-antibodies may have positive agonist effects on parasympathetic heart rate control of chagasic patients.Foram estudadas as respostas cronotrĂłpicas cardĂ­acas Ă  manobra de Valsalva e ao exercĂ­cio dinĂąmico de vinte pacientes chagĂĄsicos com função ventricular esquerda normal e sem alteraçÔes da contractilidade segmentar por ecocardiografia bidimensional. O aumento absoluto da frequĂȘncia cardĂ­aca dos pacientes (Δ = 21,5 ± 10 bpm, M ± DP) durante a manobra de Valsalva foi significativamente menor quando se comparava ao grupo controle (Δ = 31,30 ± 70, p = 0,03). A frequĂȘncia cardĂ­aca mĂ­nima (58,24 ± 8,90 vs 62,80 ± 10, p = 0,68) e a diminuição da frequĂȘncia cardĂ­aca absoluta no final da manobra (Δ = 38,30 ± 13 vs Δ = 31,47 ± 17, p = 0,10) nĂŁo foram diferentes em comparação com o grupo controle. A aceleração inicial da frequĂȘncia cardĂ­aca durante o exercĂ­cio dinĂąmico (Δ = 12 ± 7,55 vs Δ = 19 ± 7,27, p = 0,01) tambĂ©m foi menor, mas a recuperação da frequĂȘncia cardĂ­aca, durante os primeiros dez segundos, foi maior no grupo sero-positivos [mediana:14 (intervalo interquartil: 9,75-17,50) vs 5 (0 - 8,75), p = 0,001]. Os nĂ­veis sĂ©ricos de auto-anticorpos muscarĂ­nicos cardĂ­acos foram significativamente maiores nos pacientes chagĂĄsicos do que no grupo controle [(mediana: 34,58 densidade Ăłptica (intervalo interquartil 17 - 46,5) vs (mediana: 0, intervalo interquartil 0 - 22,25) p = 0,001] e a correlação Ă© significativa e direta (r = 0,68, p = 0,002) com o inĂ­cio da recuperação da frequĂȘncia cardĂ­aca durante o exercĂ­cio dinĂąmico. Os resultados desta investigação sugerem que indiretamente, os auto-anticorpos muscarĂ­nicos cardĂ­acos, podem ter ação agonista positiva sobre o controle parassimpĂĄtico da frequĂȘncia cardĂ­aca dos pacientes chagĂĄsicos

    Ionic fragmentation mechanisms of 2,2,2-trifluoroethanol following excitation with synchrotron radiation

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    Gaseous 2,2,2-trifluoroethanol (TFE) is excited with synchrotron radiation between 10 and 1000 eV and the ejected electrons and positive ions are detected in coincidence. In the valence-electron energy region, the most abundant species is CH2OH+. Other fragments, including ions produced by atomic rearrangements, are also detected; the most abundant are COH+, CFH2 + and CF2H2 +. The energies of electronic transitions from C 1s, O 1s and F 1s orbitals to vacant molecular orbitals are determined. A site-specific C 1s excitation is observed. The photofragmentation mechanisms after the excitation of core-shell electrons are inferred from analysis of the shape and slope of the coincidence between two charged fragments in the bi-dimensional coincidence spectra. The spectra are dominated by islands that correspond to the coincidence of H+ with several charged fragments. One of the most important channels leads to the formation of CH2OH+ and CF3 + in a concerted mechanism.Fil: Bava, Yanina Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgånica ; ArgentinaFil: Berrueta Martinez, Yanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgånica ; ArgentinaFil: Moreno Betancourt, Angelica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgånica ; ArgentinaFil: Erben, Mauricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgånica ; ArgentinaFil: Cavasso Filho, Reinaldo L.. Universidade Federal Do Abc; BrasilFil: Della Védova, Carlos Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgånica ; ArgentinaFil: Romano, Rosana Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgånica ; Argentin

    1H–NMR fingerprinting and supervised pattern recognition to evaluate the stability of virgin olive oil during storage

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    Metabolomic fingerprinting of virgin olive oil (VOO) by 1H NMR spectroscopy was used to study its stability during storage simulating normal shelf life conditions during its commercialization. A representative set of VOOs covering the full range of possible chemical compositions were exposed to light (500 lux for 12 h/day) at 25 °C for 12 months or stored in the dark at 25 °C, 30 °C and 35 °C for 24 months. Multivariate data analysis of the 1H NMR spectra of the oil samples provided classification models to evaluate VOO freshness and to verify the light exposure of the VOO during storage, as well as regression models to determine VOO storage time and tentatively the best before date of a fresh VOO. These predictive models disclosed the chemical compounds responsible for the compositional changes in VOO due to hydrolytic and oxidative degradation taking place during its storage, and confirmed that light and increasing temperature enhance these processes. The presence of characteristic resonances of hydroperoxides (primary oxidation products) and the decrease of 1H signals assigned to phenolic compounds, mainly secoiridoid derivatives, and other minor compounds such as fatty acids, squalene and native (E)-2-hexenal present in fresh VOO revealed its oxidative degradation. Further, the emergence of low intensity 1H signals of saturated aldehydes meant that the secondary oxidation process has started at a low rate and yield. Moreover, the decrease of the 1H signals of triacylglycerides and sn-1,2-diacylglycerides, and the increase of sn-1,3-diacylglycerides indicated that hydrolytic degradation of VOO and diacylglyceride isomerisation was occurring. 1H NMR fingerprint of VOO together with pattern recognition techniques afford relevant information to assess the quality of VOOs taking into consideration legal, sensory and health-promoting aspects.This work was supported by the European Commission within the Horizon 2020 Programme [grant agreement No. 635690, 2014–2020], and developed in the framework of the project OLEUM “Advanced solutions for assuring authenticity and quality of olive oil at global scale”. The information contained in this article reflects the authors’views; the European Commission is not liable for any use of the information contained herein

    Morphogenesis of the sexual phase of the epiphytic ferns Microgramma mortoniana and Pleopeltis macrocarpa (Polypodiaceae) Punta Lara Natural Reserve, Buenos Aires, Argentina

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    Sexual morphogenesis phase of the epiphytic ferns Microgramma mortoniana and Pleopeltis macrocarpa (Polypodiaceae) from Punta Lara Natural Reserve, Buenos Aires, Argentina. The Punta LaraNatural Reserve is located on the riverside of the La Plata River in the province of Buenos Aires, Argentina. Itis the Southernmost relict in the world of subtropical riparian forest. The epiphytic ferns studied in this workbelong to the Polypodiaceae family: Microgramma mortoniana and Pleopeltis macrocarpa. Plant communitiesare subject to high levels of anthropization and introduction of exotic species. The goals of this work areto provide information on the morphogenesis of epiphytic gametophytes and to extend knowledge of their lifecycles, contributing to their conservation. Sowing was carried out in Dyer medium. In both species the sporesare monolete, ellipsoidal, yellowish and with verrucate sculpture. The equatorial diameter is 60-61 ÎŒm, the polardiameter is 39-42 ÎŒm. The germination is the Vittaria type; in M. mortoniana occurs at 20 days, while in P.macrocarpa occurs at six days. The filaments are uniseriate of 3-6 cells in length. The gametophyte development is Drynaria type. The cordated form is given after 40 days. In M. mortoniana, buds originated after 40 days. In P. macrocarpa, after 120 days, clathrate trichomes scale-like appear mainly on the margins of the gametophyte. The gametangia are typical of leptosporangiate ferns. The sporophyte of M. mortoniana emerged after 120 days and that of P. macrocarpa arose after 500 days, its blades are simple, spatulate and unicellular and multicellular branching hairs were observed. The germination pattern, gametophyte development, the presence of a lipid globule in the prothalic cell and the formation of unicellular capitated hairs are relevant characters that could be considered for systematic group. The delay in the formation of sporophytes through sexual reproduction, allows us to infer that the success of their establishment in situ would be given by the vegetative reproduction through creeping rhizomes and buds of gametophytesFil: Gorrer, Daniel Alejandro. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. CĂĄtedra de MorfologĂ­a Vegetal; ArgentinaFil: Berrueta, Pedro Cayetano. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. CĂĄtedra de MorfologĂ­a Vegetal; ArgentinaFil: Ramos Giacosa, Juan Pablo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. CĂĄtedra de MorfologĂ­a Vegetal; ArgentinaFil: Giudice, G. E.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. CĂĄtedra de MorfologĂ­a Vegetal; ArgentinaFil: Luna, M. L.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. CĂĄtedra de MorfologĂ­a Vegetal; Argentin

    Stepwise strategy based on 1H-NMR fingerprinting in combination with chemometrics to determine the content of vegetable oils in olive oil mixtures

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    1H NMR fingerprinting of edible oils and a set of multivariate classification and regression models organised in a decision tree is proposed as a stepwise strategy to assure the authenticity and traceability of olive oils and their declared blends with other vegetable oils (VOs). Oils of the ‘virgin olive oil’ and ‘olive oil’ categories and their mixtures with the most common VOs, i.e. sunflower, high oleic sunflower, hazelnut, avocado, soybean, corn, refined palm olein and desterolized high oleic sunflower oils, were studied. Partial least squares (PLS) discriminant analysis provided stable and robust binary classification models to identify the olive oil type and the VO in the blend. PLS regression afforded models with excellent precisions and acceptable accuracies to determine the percentage of VO in the mixture. The satisfactory performance of this approach, tested with blind samples, confirm its potential to support regulations and control bodies

    Use of antenatal corticosteroids at health facilities and communities in low-and-middle income countries.

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    BACKGROUND: Antenatal corticosteroids (ACS) for women at high risk of preterm birth is an effective intervention to reduce neonatal mortality among preterm babies delivered in hospital settings, but has not been widely used in low-middle resource settings. We sought to assess the rates of ACS use at all levels of health care in low and middle income countries (LMIC). METHODS: We assessed rates of ACS in 7 sites in 6 LMIC participating in the Eunice Kennedy Shriver National Institute of Child Health and Human Development\u27s Global Network for Women and Children\u27s Health Research Antenatal Corticosteroids Trial (ACT), a cluster-randomized trial to assess the feasibility, effectiveness, and safety of a multifaceted intervention designed to increase the use of ACS. We conducted this analysis using data from the control clusters, which did not receive any components of the intervention and intended to follow usual care. We included women who delivered an infant with a birth weight \u3c5th percentile, a proxy for preterm birth, and were enrolled in the Maternal Newborn Health (MNH) Registry between October 2011 and March 2014 in all clusters. A survey of the site investigators regarding existing policies on ACS in health facilities and for health workers in the community was part of pre-trial activities. RESULTS: Overall, of 51,523 women delivered in control clusters across all sites, the percentage of \u3c5th percentile babies ranged from 3.5 % in Kenya to 10.7 % in Pakistan. There was variation among the sites in the use of ACS at all hospitals and among those hospitals having cesarean section and neonatal care capabilities (bag and mask and oxygen or mechanical ventilation). Rates of ACS use for \u3c5th percentile babies in all hospitals ranged from 3.8 % in the Kenya sites to 44.5 % in the Argentina site, and in hospitals with cesarean section and neonatal care capabilities from 0 % in Zambia to 43.5 % in Argentina. ACS were rarely used in clinic or home deliveries at any site. Guidelines for ACS use at all levels of the health system were available for most of the sites. CONCLUSION: Our study reports an overall low utilization of ACS among mothers of \u3c5th percentile infants in hospital and clinic deliveries in LMIC
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