875 research outputs found
Atlas versus range maps: robustness of chorological relationships to distribution data types in European mammals
Aim Chorological relationships describe the patterns of distributional overlap
among species. In addition to revealing biogeographical structure, the resulting
clusters of species with similar geographical distributions can serve as natural
units in conservation planning. Here, we assess the extent to which temporal,
methodological and taxonomical differences in the source of species’ distribution
data can affect the relationships that are found
Eye drop Self-medication: Comparative Questionnaire-based study of two Latin American cities.
A broad spectrum of ocular symptoms are treated by self-medication with commercial eye-drops. This behavior threatens individuals' visual health. In Latin America, evidence is poor.
Objective: To detect, characterize and compare patterns of ophthalmic self-medication between Córdoba (Argentina) and Barranquilla (Colombia).Design: Analytic, cross-sectional and comparative population-based study. Setting: Two private tertiary care ophthalmology centers from Córdoba, Argentina, and Barranquilla, Colombia.Participants: Patients 18 years of age or older who consulted for the first time in this two institutions duringAugust-November 2009, were included. A number of 570 patients were enrrolled.Methods: Data collected through a semi-structured questionnaire. Main outcome measure: To determine thefrequency of self-medication with eyedrops on a specific population of two cities in Latin America.Results: Comparable rates of ocular self-medication were found (25.6% and 25.7% for Cordoba and Barranquilla, respectively). The percentage of men and women who self-medicated was not significantly different between both samples. The major source of eye drops recommendation in the Argentineans patients was the pharmacist (31%); while the social source was predominant in Colombian individuals (53%). In Cordoba, the most frequently used product was a non-steroidal anti-inflammatory drop in combination with a vasoconstrictive agent (32%); while in Barranquilla, antibiotic eye drops were preferred (33%). Self-medication was higher between the ages of 31 and 50 years old in Argentinean citizens (28%) and between 18 to 31 years old in the Colombiancommunity (39%). This habit was found mostly in patients who completed university studies in Cordoba (33%); in Barranquilla, individuals with lower educational level practice more this behavior (36%).Conclusion: In both populations, patients commonly treat ocular conditions by self-medicating. Currently, anincreasing number of eye drops are obtainable without prescription and a high percentage of self-medicated patients in both samples ignore the possible side effects of the used medication.Fil: Marquez, Gabriel. Fundación VER; ArgentinaFil: Hildegard Piñeros-Heilbron. Fundación Oftalmológica del Caribe; ColombiaFil: Sanchez, Victoria M.. Fundación VER; ArgentinaFil: Torres, Victor Eduardo Roque. Fundación VER; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Estudios sobre Cultura y Sociedad. Universidad Nacional de Córdoba. Centro de Investigaciones y Estudios sobre Cultura y Sociedad; ArgentinaFil: Gramajo, Ana L.. Fundación VER; ArgentinaFil: Juarez, Claudio P.. Fundación VER; Argentina. Fundación Oftalmológica del Caribe; ColombiaFil: Peña, Fernando. Fundación Oftalmológica del Caribe; ColombiaFil: Luna, José D.. Fundación VER; Argentin
Brotes de ébola y la presencia de murciélagos en áreas humanizadas: un análisis biogeográfico
Recientemente se ha demostrado que existe una relación positiva entre la deforestación en África y la aparición de brotes de Ébola en humanos. Sin embargo, los mecanismos que median en esta relación aún son desconocidos. Se ha sugerido la facilitación del acceso del ser humano a la selva, y por tanto su mayor contacto con la fauna autóctona; y el favorecimiento ambiental de la fauna capaz de transmitir el virus, incluidos los murciélagos de la fruta (familia Pteropodidae). Nuestro objetivo ha sido tratar de comprobar el posible papel de los murciélagos de la fruta en la transmisión del Ébola en zonas recientemente deforestadas, mediante un enfoque hipotético-deductivo basado en la biogeografía de estas especies.
Las actividades humanas podrían haber contribuido significativamente a definir las áreas de distribución de 15 especies de murciélagos de la fruta. Esta contribución es más significativa aún cuando el área de estudio se restringe a África central y occidental, contexto biogeográfico favorable a la presencia del virus del Ébola en la naturaleza. La influencia humana se intensifica en el caso de tres especies en particular: Eidolon helvum, Epomops franqueti e Hypsignatus monstrosus, cuyo vínculo con el Ébola está demostrado a través de pruebas serológicas y biomoleculares. Además, nuestro análisis proporciona evidencias de que las zonas donde la actividad humana favorece la presencia de 7 especies de murciélagos de la fruta están significativamente solapadas con la localización de brotes de Ébola cuya relación con eventos de deforestación se ha sugerido con anterioridad. Entre éstas especies hay 5 cuya relación con el Ébola está confirmada en laboratorio: las tres antes citadas, más Micropteropus pusillus y Rousettus aegyptiacus. Esto sugiere la existencia de un vínculo positivo entre la pérdida de bosque y la presencia de murciélagos de la fruta con capacidad de transmitir la enfermedad, en zonas donde infecciones de Ébola en seres humanos han tenido lugar.UKAID y USAID a través de CIFOR Bushmeat Research Initiative; proyecto CGL2016-76747-R del Ministerio de Economía, Industria y Competividad y Fondos FEDER. // Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
Covalently Cross-Linked Nanoparticles Based on Ferulated Arabinoxylans Recovered from a Distiller’s Dried Grains Byproduct
The purpose of this investigation was to extract ferulated arabinoxylans (AX) from
dried distillers’ grains with solubles (DDGS) plus to investigate their capability to form covalently
cross-linked nanoparticles. AX registered 7.3 µg of ferulic acid/mg polysaccharide and molecular
weight and intrinsic viscosity of 661 kDa and 149 mL/g, correspondingly. Fourier transform infrared
spectroscopy (FTIR) was used to confirm the identity of this polysaccharide. AX formed laccase
induced covalent gels at 1% (w/v), which registered an elastic modulus of 224 Pa and a content
of FA dimers of 1.5 µg/mg polysaccharide. Scanning electron microscopy pictures of AX gels
exhibited a microstructure resembling a rough honeycomb. AX formed covalently cross-linked
nanoparticles (NAX) by coaxial electrospray. The average hydrodynamic diameter of NAX determined
by dynamic light scattering was 328 nm. NAX presented a spherical and regular shape by transmission
electron microscopy analysis. NAX may be an attractive material for pharmaceutical and biomedical
applications and an option in sustainable DDGS use
A decade of theory as reflected in Psychological Science (2009–2019)
The dominant belief is that science progresses by testing theories and moving towards theoretical consensus. While it’s implicitly assumed that psychology operates in this manner, critical discussions claim that the field suffers from a lack of cumulative theory. To examine this paradox, we analysed research published in Psychological Science from 2009–2019 (N = 2,225). We found mention of 359 theories in-text, most were referred to only once. Only 53.66% of all manuscripts included the word theory, and only 15.33% explicitly claimed to test predictions derived from theories. We interpret this to suggest that the majority of research published in this flagship journal is not driven by theory, nor can it be contributing to cumulative theory building. These data provide insight into the kinds of research psychologists are conducting and raises questions about the role of theory in the psychological sciences
Integral Field Spectroscopy of Blue Compact Dwarf Galaxies
We present results on integral-field optical spectroscopy of five luminous
Blue Compact Dwarf galaxies. The data were obtained using the fiber system
INTEGRAL attached at the William Herschel telescope. The galaxies Mrk 370, Mrk
35, Mrk 297, Mrk 314 and III Zw 102 were observed. The central 33"x29" regions
of the galaxies were mapped with a spatial resolution of 2"/spaxel, except for
Mrk 314, in which we observed the central 16"x12" region with a resolution of
0.9"/spaxel$. We use high-resolution optical images to isolate the star-forming
knots in the objects; line ratios, electron densities and oxygen abundances in
each of these regions are computed. We build continuum and emission-line
intensity maps as well as maps of the most relevant line ratios: [OIII]5007\Hb,
[NII]6584\Ha, and Ha\Hb, which allow us to obtain spatial information on the
ionization structure and mechanisms. We also derive the gas velocity field from
the Ha and [OIII]5007 emission lines.
We find that all the five galaxies are in the high end of the metallicity
range of Blue Compact Dwarf galaxies, with oxygen abundances varying from
Z\sun~0.3 to Z\sun~1.5. The objects show HII-like ionization in the whole field
of view, except the outer regions of IIIZw102 whose large [NII]6584/Ha values
suggest the presence of shocks. The five galaxies display inhomogeneous
extinction patterns, and three of them have high Ha/Hb ratios, indicative of a
large dust content; all galaxies display complex, irregular velocity fields in
their inner regions.Comment: 26 pages, 14 figures, 5 tables. Accepted for publication in the Ap
Reduced levels of intracellular calcium releasing in spermatozoa from asthenozoospermic patients
<p>Abstract</p> <p>Background</p> <p>Asthenozoospermia is one of the most common findings present in infertile males characterized by reduced or absent sperm motility, but its aetiology remains unknown in most cases. In addition, calcium is one of the most important ions regulating sperm motility. In this study we have investigated the progesterone-evoked intracellular calcium signal in ejaculated spermatozoa from men with normospermia or asthenozoospermia.</p> <p>Methods</p> <p>Human ejaculates were obtained from healthy volunteers and asthenospermic men by masturbation after 4–5 days of abstinence. For determination of cytosolic free calcium concentration, spermatozoa were loaded with the fluorescent ratiometric calcium indicator Fura-2.</p> <p>Results</p> <p>Treatment of spermatozoa from normospermic men with 20 micromolar progesterone plus 1 micromolar thapsigargin in a calcium free medium induced a typical transient increase in cytosolic free calcium concentration due to calcium release from internal stores. Similar results were obtained when spermatozoa were stimulated with progesterone alone. Subsequent addition of calcium to the external medium evoked a sustained elevation in cytosolic free calcium concentration indicative of capacitative calcium entry. However, when progesterone plus thapsigargin were administered to spermatozoa from patients with asthenozoospermia, calcium signal and subsequent calcium entry was much smaller compared to normospermic patients. As expected, pretreatment of normospermic spermatozoa with both the anti-progesterone receptor c262 antibody and with progesterone receptor antagonist RU-38486 decreased the calcium release induced by progesterone. Treatment of spermatozoa with cytochalasin D or jasplakinolide decreased the calcium entry evoked by depletion of internal calcium stores in normospermic patients, whereas these treatments proved to be ineffective at modifying the calcium entry in patients with asthenozoospermia.</p> <p>Conclusion</p> <p>Our results suggest that spermatozoa from asthenozoospermic patients present a reduced responsiveness to progesterone.</p
EGF functionalized polymer-coated gold nanoparticles promote EGF photostability and EGFR internalization for photothermal therapy
The application of functionalized nanocarriers on photothermal therapy for cancer ablation has wide interest. The success of this application depends on the therapeutic efficiency and biocompatibility of the system, but also on the stability and biorecognition of the conjugated protein. This study aims at investigating the hypothesis that EGF functionalized polymer -coated gold nanoparticles promote EGF photostability and EGFR internalization, making these conjugated particles suitable for photothermal therapy. The conjugated gold nanoparticles (100-200 nm) showed a plasmon absorption band located within the near infrared range (650-900 nm), optimal for photothermal therapy applications. The effects of temperature, of polymer-coated gold nanoparticles and of UVB light (295nm) on the fluorescence properties of EGF have been investigated with steady-state and time-resolved fluorescence spectroscopy. The fluorescence properties of EGF, including the formation of Trp and Tyr photoproducts, is modulated by temperature and by the intensity of the excitation light. The presence of polymeric-coated gold nanoparticles reduced or even avoided the formation of Trp and Tyr photoproducts when EGF is exposed to UVB light, protecting this way the structure and function of EGF. Cytotoxicity studies of conjugated nanoparticles carried out in normal-like human keratinocytes showed small, concentration dependent decreases in cell viability (0-25%). Moreover, conjugated nanoparticles could activate and induce the internalization of overexpressed Epidermal Growth Factor Receptor in human lung carcinoma cells. In conclusion, the gold nanoparticles conjugated with Epidermal Growth Factor and coated with biopolymers developed in this work, show a potential application for near infrared photothermal therapy, which may efficiently destroy solid tumours, reducing the damage of the healthy tissue.Support was provided by: Fundacao para a Ciencia e Tecnologia (FCT) for the financial support under the project reference PTDC/BBB-BMC/0611/2012 [https://www.fct.pt/apoios/projectos)]. The work at CBMA was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI) [https://www.fct.pt/apoios/projectos]; European Commission through the project H2020-644242-SAPHELY (https://saphely.eu/project.php) and the project H2020-634013-2-PHOCNOSIS [http://cordis.europa.eu/project/rcn/193268_en.html].The authors would like to thank Fundacao para a Ciencia e Tecnologia (FCT) for the financial support under the project reference PTDC/BBB-BMC/0611/2012. The work at CBMA was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI). The authors acknowledge the funding from the European Commission through the project H2020-644242-SAPHELY and the project H2020-634013-2-PHOCNOSIS. Finally, the authors would also like to thank the master student Joao Lopes from Universidade Lusofona (Portugal) for the help with in vitro cytotoxic assays. Isabel Correia acknowledges FCT for Investigator FCT contract.info:eu-repo/semantics/publishedVersio
Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials.
Funder: laura and john arnold foundationBACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care
- …