2,223 research outputs found

    The costs of preventing and treating chagas disease in Colombia

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    Background: The objective of this study is to report the costs of Chagas disease in Colombia, in terms of vector disease control programmes and the costs of providing care to chronic Chagas disease patients with cardiomyopathy. Methods: Data were collected from Colombia in 2004. A retrospective review of costs for vector control programmes carried out in rural areas included 3,084 houses surveyed for infestation with triatomine bugs and 3,305 houses sprayed with insecticide. A total of 63 patient records from 3 different hospitals were selected for a retrospective review of resource use. Consensus methodology with local experts was used to estimate care seeking behaviour and to complement observed data on utilisation. Findings: The mean cost per house per entomological survey was 4.4(inUS4.4 (in US of 2004), whereas the mean cost of spraying a house with insecticide was 27.Themaincostdriverofsprayingwasthepriceoftheinsecticide,whichvariedgreatly.TreatmentofachronicChagasdiseasepatientcostsbetween27. The main cost driver of spraying was the price of the insecticide, which varied greatly. Treatment of a chronic Chagas disease patient costs between 46.4 and 7,981peryearinColombia,dependingonseverityandthelevelofcareused.Combiningcostandutilisationestimatestheexpectedcostoftreatmentperpatientyearis7,981 per year in Colombia, depending on severity and the level of care used. Combining cost and utilisation estimates the expected cost of treatment per patient-year is 1,028, whereas lifetime costs averaged $11,619 per patient. Chronic Chagas disease patients have limited access to healthcare, with an estimated 22% of patients never seeking care. Conclusion: Chagas disease is a preventable condition that affects mostly poor populations living in rural areas. The mean costs of surveying houses for infestation and spraying infested houses were low in comparison to other studies and in line with treatment costs. Care seeking behaviour and the type of insurance affiliation seem to play a role in the facilities and type of care that patients use, thus raising concerns about equitable access to care. Preventing Chagas disease in Colombia would be cost-effective and could contribute to prevent inequalities in health and healthcare.Wellcome Trus

    Spectroscopy of 28^{28}Na: shell evolution toward the drip line

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    Excited states in 28^{28}Na have been studied using the β\beta-decay of implanted 28^{28}Ne ions at GANIL/LISE as well as the in-beam γ\gamma-ray spectroscopy at the NSCL/S800 facility. New states of positive (Jπ^{\pi}=3,4+^+) and negative (Jπ^{\pi}=1-5^-) parity are proposed. The former arise from the coupling between 0d_5/2\_{5/2} protons and a 0d_3/2\_{3/2} neutron, while the latter are due to couplings with 1p_3/2\_{3/2} or 0f_7/2\_{7/2} neutrons. While the relative energies between the Jπ^{\pi}=1-4+^+ states are well reproduced with the USDA interaction in the N=17 isotones, a progressive shift in the ground state binding energy (by about 500 keV) is observed between 26^{26}F and 30^{30}Al. This points to a possible change in the proton-neutron 0d_5/2\_{5/2}-0d_3/2\_{3/2} effective interaction when moving from stability to the drip line. The presence of Jπ^{\pi}=1-4^- negative parity states around 1.5 MeV as well as of a candidate for a Jπ^{\pi}=5^- state around 2.5 MeV give further support to the collapse of the N=20 gap and to the inversion between the 0f_7/2\_{7/2} and 1p_3/2\_{3/2} levels below Z=12. These features are discussed in the framework of Shell Model and EDF calculations, leading to predicted negative parity states in the low energy spectra of the 26^{26}F and 25^{25}O nuclei.Comment: Exp\'erience GANIL/LISE et NSCL/S80

    Enhancement of nematic order and global phase diagram of a lattice model for coupled nematic systems

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    We use an infinite-range Maier-Saupe model, with two sets of local quadrupolar variables and restricted orientations, to investigate the global phase diagram of a coupled system of two nematic subsystems. The free energy and the equations of state are exactly calculated by standard techniques of statistical mechanics. The nematic-isotropic transition temperature of system A increases with both the interaction energy among mesogens of system B, and the two-subsystem coupling JJ. This enhancement of the nematic phase is manifested in a global phase diagram in terms of the interaction parameters and the temperature TT. We make some comments on the connections of these results with experimental findings for a system of diluted ferroelectric nanoparticles embedded in a nematic liquid-crystalline environment.Comment: 11 pages, 3 figures, to appear in Volume 42 of the Brazilian Journal of Physic

    Towards a higher photostability of ZnO photo-electrocatalysts in the degradation of organics by using MMO substrates

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    In this work, it is proposed a novel strategy to increase the photostability of the ZnO photoelectrocatalyst under prolonged light irradiation, without the addition or deposition of metals and/or semiconductor oxides during their synthesis. This strategy is based on the use of a mixed metal oxide (MMO-Ru0.3Ti0.7O2) coating as the substrate for the electrodeposition of ZnO. To assess it, the electrodeposition of ZnO films on Ti and Ti/MMO substrates and the photoelectrocatalytic activity of these materials for the degradation of the herbicide clopyralid were studied. The results showed that the substrate directly influenced the photo-stability of the ZnO film. Under the incidence of UV light and polarization, the novel Ti/MMO/ZnO electrode showed greater photocurrent stability as compared to Ti/ZnO, which is a very important outcome because the behavior of these electrodes was similar when compared in terms of the degradation of clopyralid. Single electrolysis was not able to degrade efficiently clopyralid at the different potentials studied. However, the irradiation of UV light on the polarized surface of the Ti/ZnO and Ti/MMO/ZnO electrodes increased markedly the degradation rate of clopyralid. A synergistic effect was observed between light and electrode polarization, since the rate of degradation of clopyralid was twice as high in photoelectrocatalysis (PhEC) than in photocatalysis (PhC) and different intermediates were formed. From these results, mechanisms of degradation of clopyralid for the PhC and PhEC systems with the Ti/ZnO and Ti/MMO/ZnO electrodes were presented. Therefore, the Ti/MMO/ZnO electrode could be a cheap and simple alternative to be applied in the efficient photodegradation of organic pollutants, presenting the great advantage of having a facile synthesis and high capacity to work at relatively low potentials.En este trabajo se propone una estrategia novedosa para incrementar la fotoestabilidad del fotoelectrocatalizador de ZnO bajo irradiación de luz prolongada, sin la adición o deposición de metales y / o óxidos semiconductores durante su síntesis. Esta estrategia se basa en el uso de un óxido de metal mixto (MMO-Ru 0.3 Ti 0.7 O 2) revestimiento como sustrato para la electrodeposición de ZnO. Para evaluarlo se estudió la electrodeposición de películas de ZnO sobre sustratos de Ti y Ti / MMO y la actividad fotoelectrocatalítica de estos materiales para la degradación del herbicida clopyralid. Los resultados mostraron que el sustrato influyó directamente en la fotoestabilidad de la película de ZnO. Bajo la incidencia de la luz ultravioleta y la polarización, el nuevo electrodo de Ti / MMO / ZnO mostró una mayor estabilidad de fotocorriente en comparación con Ti / ZnO, lo cual es un resultado muy importante porque el comportamiento de estos electrodos fue similar en términos de degradación de clopyralid. La electrólisis simple no fue capaz de degradar eficazmente la clopiralida a los diferentes potenciales estudiados. Sin embargo, la irradiación de luz ultravioleta sobre la superficie polarizada de los electrodos de Ti / ZnO y Ti / MMO / ZnO aumentó notablemente la tasa de degradación del clopiralida. Se observó un efecto sinérgico entre la luz y la polarización del electrodo, ya que la tasa de degradación de clopiralida fue dos veces mayor en fotoelectrocatálisis (PhEC) que en fotocatálisis (PhC) y se formaron diferentes intermedios. A partir de estos resultados, se presentaron los mecanismos de degradación de clopiralida para los sistemas PhC y PhEC con los electrodos Ti / ZnO y Ti / MMO / ZnO. Por tanto, el electrodo Ti / MMO / ZnO podría ser una alternativa barata y sencilla para ser aplicada en la fotodegradación eficiente de contaminantes orgánicos, presentando la gran ventaja de tener una síntesis fácil y alta capacidad para trabajar a potenciales relativamente bajos. Se observó un efecto sinérgico entre la luz y la polarización del electrodo, ya que la tasa de degradación de clopiralida fue dos veces mayor en fotoelectrocatálisis (PhEC) que en fotocatálisis (PhC) y se formaron diferentes intermedios. A partir de estos resultados, se presentaron los mecanismos de degradación de clopiralida para los sistemas PhC y PhEC con los electrodos Ti / ZnO y Ti / MMO / ZnO. Por tanto, el electrodo Ti / MMO / ZnO podría ser una alternativa barata y sencilla para ser aplicada en la fotodegradación eficiente de contaminantes orgánicos, presentando la gran ventaja de tener una síntesis fácil y alta capacidad para trabajar a potenciales relativamente bajos. Se observó un efecto sinérgico entre la luz y la polarización del electrodo, ya que la tasa de degradación de clopiralida fue dos veces mayor en fotoelectrocatálisis (PhEC) que en fotocatálisis (PhC) y se formaron diferentes intermedios. A partir de estos resultados, se presentaron los mecanismos de degradación de clopiralida para los sistemas PhC y PhEC con los electrodos Ti / ZnO y Ti / MMO / ZnO. Por tanto, el electrodo Ti / MMO / ZnO podría ser una alternativa barata y sencilla para ser aplicada en la fotodegradación eficiente de contaminantes orgánicos, presentando la gran ventaja de tener una síntesis fácil y alta capacidad para trabajar a potenciales relativamente bajos. dado que la tasa de degradación de clopiralida fue dos veces más alta en fotoelectrocatálisis (PhEC) que en fotocatálisis (PhC) y se formaron diferentes intermedios. A partir de estos resultados, se presentaron los mecanismos de degradación de clopiralida para los sistemas PhC y PhEC con los electrodos Ti / ZnO y Ti / MMO / ZnO. Por tanto, el electrodo Ti / MMO / ZnO podría ser una alternativa barata y sencilla para ser aplicada en la fotodegradación eficiente de contaminantes orgánicos, presentando la gran ventaja de tener una síntesis fácil y alta capacidad para trabajar a potenciales relativamente bajos. dado que la tasa de degradación de clopiralida fue dos veces más alta en fotoelectrocatálisis (PhEC) que en fotocatálisis (PhC) y se formaron diferentes intermedios. A partir de estos resultados, se presentaron los mecanismos de degradación de clopiralida para los sistemas PhC y PhEC con los electrodos Ti / ZnO y Ti / MMO / ZnO. Por tanto, el electrodo Ti / MMO / ZnO podría ser una alternativa barata y sencilla para ser aplicada en la fotodegradación eficiente de contaminantes orgánicos, presentando la gran ventaja de tener una síntesis fácil y alta capacidad para trabajar a potenciales relativamente bajos

    Low frequency of TERT promoter mutations in gastrointestinal stromal tumors (GISTs).

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    Somatic mutations in the promoter region of telomerase reverse transcriptase (TERT) gene, mainly at positions c. − 124 and c. − 146 bp, are frequent in several human cancers; yet its presence in gastrointestinal stromal tumor (GIST) has not been reported to date. Herein, we searched for the presence and clinicopathological association of TERT promoter mutations in genomic DNA from 130 bona fide GISTs. We found TERT promoter mutations in 3.8% (5/130) of GISTs. The c. − 124C4T mutation was the most common event, present in 2.3% (3/130), and the c. − 146C4T mutation in 1.5% (2/130) of GISTs. No significant association was observed between TERT promoter mutation and patient’s clinicopathological features. The present study establishes the low frequency (4%) of TERT promoter mutations in GISTs. Further studies are required to confirm our findings and to elucidate the hypothetical biological and clinical impact of TERT promoter mutation in GIST pathogenesis.This project was partially supported by Barretos Cancer Hospital internal research funds (PAIP) and CNPq Universal Grant (476192/2013-7) to RMR. NCC is a recipient of an FAPESP Doctoral Fellowship (2013/25787-3). Further funding from the project ‘Microenvironment, metabolism and cancer’ that was partially supported by Programa Operacional Regional do Norte (ON.2—O Novo Norte) under the Quadro de Referência Estratégico Nacional (QREN) and the Fundo Europeu de Desenvolvimento Regional (FEDER). IPATIMUP is an Associate Laboratory of the Portuguese Ministry of Science, Technology and Higher Education that is partially supported by the FCT

    Different approaches for dealing with rare variants in family-based genetic studies: application of a Genetic Analysis Workshop 17 problem

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    Rare variants are becoming the new candidates in the search for genetic variants that predispose individuals to a phenotype of interest. Their low prevalence in a population requires the development of dedicated detection and analytical methods. A family-based approach could greatly enhance their detection and interpretation because rare variants are nearly family specific. In this report, we test several distinct approaches for analyzing the information provided by rare and common variants and how they can be effectively used to pinpoint putative candidate genes for follow-up studies. The analyses were performed on the mini-exome data set provided by Genetic Analysis Workshop 17. Eight approaches were tested, four using the trait’s heritability estimates and four using QTDT models. These methods had their sensitivity, specificity, and positive and negative predictive values compared in light of the simulation parameters. Our results highlight important limitations of current methods to deal with rare and common variants, all methods presented a reduced specificity and, consequently, prone to false positive associations. Methods analyzing common variants information showed an enhanced sensibility when compared to rare variants methods. Furthermore, our limited knowledge of the use of biological databases for gene annotations, possibly for use as covariates in regression models, imposes a barrier to further research

    Blood volume measurement with indocyanine green pulse spectrophotometry: dose and site of dye administration

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    (1) To determine the optimal administration site and dose of indocyanine green (ICG) for blood volume measurement using pulse spectrophotometry, (2) to assess the variation in repeated blood volume measurements for patients after subarachnoid hemorrhage and (3) to evaluate the safety and efficacy of this technique in patients who were treated for an intracranial aneurysm. Four repeated measurements of blood volume (BV) were performed in random order of bolus dose (10 mg or 25 mg ICG) and venous administration site (peripheral or central) in eight patients admitted for treatment of an intracranial aneurysm. Another five patients with subarachnoid hemorrhage underwent three repeated BV measurements with 25 mg ICG at the same administration site to assess the coefficient of variation. The mean +/- SD in BV was 4.38 +/- 0.88 l (n = 25) and 4.69 +/- 1.11 l (n = 26) for 10 mg and 25 mg ICG, respectively. The mean +/- SD in BV was 4.59 +/- 1.15 l (n = 26) and 4.48 +/- 0.86 l (n = 25) for central and peripheral administration, respectively. No significant difference was found. The coefficient of variance of BV measurement with 25 mg of ICG was 7.5% (95% CI: 3-12%). There is no significant difference between intravenous administration of either 10 or 25 mg ICG, and this can be injected through either a peripheral or central venous catheter. The 7.5% coefficient of variation in BV measurements determines the detectable differences using ICG pulse spectrophotometr

    Gastrointestinal complaints in runners are not due to small intestinal bacterial overgrowth

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    <p>Abstract</p> <p>Background</p> <p>Gastrointestinal complaints are common among long distance runners. We hypothesised that small intestinal bacterial overgrowth (SIBO) is present in long distance runners frequently afflicted with gastrointestinal complaints.</p> <p>Findings</p> <p>Seven long distance runners (5 female, mean age 29.1 years) with gastrointestinal complaints during and immediately after exercise without known gastrointestinal diseases performed Glucose hydrogen breath tests for detection of SIBO one week after a lactose hydrogen breath test checking for lactose intolerance. The most frequent symptoms were diarrhea (5/7, 71%) and flatulence (6/7, 86%). The study was conducted at a laboratory.</p> <p>In none of the subjects a pathological hydrogen production was observed after the intake of glucose. Only in one athlete a pathological hydrogen production was measured after the intake of lactose suggesting lactose intolerance.</p> <p>Conclusions</p> <p>Gastrointestinal disorders in the examined long distance runners were not associated with small intestinal bacterial overgrowth.</p
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