69 research outputs found
Toxicological hazard induced by sucralose to environmentally relevant concentrations in common carp (Cyprinus carpio)
Esta investigación se realizó con la intención de identificar el daño ecotoxicológico que producen en la biota acuática algunos productos edulcorantes aparentemente inocuos al ambiente. En este estudio se identificó el potencial inducido de estrés oxidativo sobre la Cyprinus carpio, una especie de interés comercial. Las carpas fueron expuestas a dos diferentes concentraciones de importancia ambiental. Los resultados mostraron un incremento en los biomarcadores de daño oxidativo especialmente en la actividad de enzimas antioxidantes en las branquias y músculo, evidenciando el impacto ambiental de estos agentes sobre especies acuáticas.Sucralose (SUC) is an artificial sweetener that is now widely used in North American and Europe; it has been detected in a wide variety of aquatic environments. It is considered safe for human consumption but its effects in the ecosystem have not yet been studied in depth, since limited ecotoxicological data are available in the peer-reviewed literature. This study aimed to evaluate potential SUC-induced toxicological hazard in the blood, brain, gill, liver and muscle of Cyprinus carpio using oxidative stress biomarkers. Carps were exposed to two different environmentally relevant concentrations (0.05 and 155μgL-1) for different exposure times (12, 24, 48, 72 and 96h). The following biomarkers were evaluated: lipid peroxidation (LPX), hydroperoxide content (HPC) and protein carbonyl content (PCC), as well as the activity of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT). SUC was determined by high pressure liquid chromatography tandem mass spectrometry techniques (HPLC)-MS/MS. Results show a statically significant increase in LPX, HPC, PCC (P<0.05) especially in gill, brain and muscle, as well as significant changes in the activity of antioxidant enzymes in gill and muscle. Furthermore, the biomarkers employed in this study are useful in the assessment of the environmental impact of this agent on aquatic species
Knowledge, Attitudes, Risk Perceptions, and Practices of Spanish Adolescents Toward the COVID-19 Pandemic: Validation and Results of the Spanish Version of the Questionnaire
Background: Adolescence is a period with physical, psychological, biological, intellectual, and social changes in which there is usually little perception of risk. COVID-19 has generated constant situations of change and uncertainty worldwide. During the pandemic, the acquisition of preventive behaviors has been relevant. Various studies carried out with adults associate risk perception and the implementation of preventive behaviors with knowledge about the COVID-19 and with age, but there are not many studies with adolescents. Therefore, the objective is to validate, in Spanish, the questionnaire of the knowledge, attitudes, risk perceptions, and practices of adolescents toward the pandemic, and analyze it according to sociodemographic characteristics.Method: This study was a descriptive cross-sectional study, which included adolescents between the ages of 12-18 (n = 354). First, a translation and a back-translation of the questionnaire were performed. The questionnaire was presented in several high schools chosen by convenience sampling and following a non-probabilistic snowball sampling. Reliability and validity analyses were then carried out and the relationships between the different sociodemographic variables (gender, place of residence, level of education, if the person was in a sentimental relationship, and financial aid) were analyzed.Results: The reliability of the questionnaire is acceptable (ordinal alpha = 77%). Knowledge was higher in women, and in those with a higher level of education; and were lower in those who lived in smaller towns, as well as in those who had a member of their family receiving financial aid. In terms of attitudes and risk perceptions, younger adolescents had higher scores, and those who had a member of their family receiving financial aid, lower.Conclusion: The questionnaire is a reliable tool in the Spanish adolescent population. Knowledge was influenced by gender, place of residence, level of education, and financial aid. Attitudes and risk perceptions were influenced by age and financial aid. For practices, no predictors were found. In general, adolescents scored lower on knowledge about COVID-19, but they scored higher on COVID-19 safety practices
Actividad inhibitoria sobre a-glucosidasa y a-amilasa de extractos acuosos de algunas especias utilizados en la cocina mexicana
La diabetes es una de las principales causasde morbilidad y mortalidad en el mundo.Muchos estudios están dirigidos haciala búsqueda de componentes dietariosque sean benéficos para su tratamiento yprevención. El objetivo del presente estudiofue examinar el efecto antioxidante einhibitorio de a-glucosidasa y a-amilasa deextractos acuosos de canela(Cinnamomumzeylanicum),comino(Cuminum cyminum),orégano(Origanum vulgare),pimienta negra(Pipar nigrum)yclavo(Eugenia caryophyllus),que son especias utilizadas comúnmente enla cocina mexicana. Se prepararon extractosacuosos (50 °C durante 3 h) y se determinóel contenido de compuestos fenólicos totales,actividad antioxidante y potencial inhibitorioin vitro de a-glucosidasa y a-amilasa. Elcontenido de compuestos fenólicos totalesvarió de 3.12 a 104.4 mg/g de muestra. Todos losextractos mostraron actividad antioxidanteque fue expresada como porcentaje deinhibición del radical DPPH- (30 % a 80 %)y capacidad inhibitoria de a-glucosidasa de22 % a 70 %. La inhibición de la actividada-amilasa se encontró de O % a 50 %. Losextractos acuosos de canela presentaronmayor capacidad inhibitoria contra la acciónde la a-glucosidasa y actividad contra el radicalDPPH-, los extractos acuosos de oréganomostraron menor inhibición de la actividad a-glucosidasa y no presentaron inhibicióncontra la actividad a-amilasa. La efectividadinhibitoria de las enzimas y el contenido decompuestos fenólicos totales no presentócorrelación. Sin embargo, se encontró unacorrelación entre la actividad antioxidantey el contenido de compuestos fenólicostotales (r2= 0.94, P < 0.05). La inhibiciónde a-glucosidasa y a-amilasa es una delas formas terapéuticas para retardar ladigestión y absorción de los carbohidratosy en consecuencia, la reducción de glucosapostprandial en sangre. El uso de especiasculinarias consumidas en los platillosmexicanos podría representar un usopotencial durante los estados tempranos dehiperglicemia
Status of the ANAIS Dark Matter Project at the Canfranc Underground Laboratory
The ANAIS experiment aims at the confirmation of the DAMA/LIBRA signal. A
detailed analysis of two NaI(Tl) crystals of 12.5 kg each grown by Alpha
Spectra will be shown: effective threshold at 1 keVee is at reach thanks to
outstanding light collection and robust PMT noise filtering protocols and the
measured background is well understood down to 3 keVee, having quantified K, U
and Th content and cosmogenic activation in the crystals. A new detector was
installed in Canfranc in March 2015 together with the two previous modules and
preliminary characterization results will be presented. Finally, the status and
expected sensitivity of the full experiment with 112 kg will be reviewed.Comment: Contributed to the 11th Patras Workshop on Axions, WIMPs and WISPs,
Zaragoza, June 22 to 26, 201
Relationship between genotoxicity and oxidative stress induced by mercury on common carp (Cyprinus carpio) tissues
Artículo científicoMercury is one of the most toxic metals in aquatic systems since it is able to induce neurobehavioral disorders as well as renal and gastrointestinal tract damage. The common carp Cyprinus carpio is an important species from both an ecological and economic viewpoint as it is consumed in many countries, the top producers being Mexico, China, India and Japan. The present study aimed to evaluate the relation between Hg-induced oxidative stress and genotoxicity in diverse tissues of C. carpio. Specimens were exposed to 0.01 mg Hg/L (the maximum per- missible limit for aquatic life protection), and lipid peroxidation, protein carbonyl content and the activity of antioxidant enzymes were evaluated at 96 h. Micronuclei frequency and DNA damage by comet assay were determined at 12, 24, 48, 72 and 96 h. Hg induced oxidative stress and genotoxicity on exposed fish, since inhibition of antioxidant enzymes activity and increases in lipid peroxidation, DNA damage and micronuclei frequency occurred. Blood, gill and liver were more susceptible to oxidative stress, while blood were more sensitive to genotoxicity. In conclusion, Hg at concentrations equal to the maximum permissible limit for aquatic life protection induced oxidative stress and genotoxicity on C. carpio, and these two effects prove to be corre- lated.Consejo Nacional de Ciencia y Tecnología (CONACyT, Project 181541) as well as the Secretaría de Investigación y Posgrado of the Instituto Politécnico Nacional, Mexico (SIP-IPN, Projects 20160871 and 20170931)
Analysis of backgrounds for the ANAIS-112 dark matter experiment
The ANAIS (Annual modulation with NaI(Tl) Scintillators) experiment aims at
the confirmation or refutation of theDAMA/LIBRA positive annual modulation
signal in the low energy detection rate, using the same target and technique,
at the Canfranc Underground Laboratory (LSC) in Spain. ANAIS-112, consisting of
nine 12.5 kg NaI(Tl) modules produced by Alpha Spectra Inc. in a 3x3matrix
configuration, is taking data smoothly in "dark matter search" mode since
August, 2017, after a commissioning phase and operation of the first detectors
during the last years in various setups. A large effort has been carried out
withinANAIS to characterize the background of sodium iodide detectors, before
unblinding the data and performing the first annual modulation analysis. Here,
the background models developed for all the nine ANAIS-112 detectors are
presented. Measured spectra from threshold to high energy in different
conditions are well described by the models based on quantified activities
independently estimated following several approaches. In the region from 1 to 6
keVee the measured, efficiency corrected background level is 3.58+-0.02 keV-1
kg-1 day-1; NaI crystal bulk contamination is the dominant background source
being 210Pb, 40K, 22Na and 3H contributions the most relevant ones. This
background level, added to the achieved 1 keVee analysis threshold (thanks to
the outstanding light collection and robust filtering procedures developed),
allow ANAIS-112 to be sensitive to the modulation amplitude measured by
DAMA/LIBRA, and able to explore at three sigma level in 5 years the WIMP
parameter region singled out by this experiment.Comment: Final version for publicatio
Background model of NaI(Tl) detectors for the ANAIS Dark Matter Project
A thorough understanding of the background sources is mandatory in any
experiment searching for rare events. The ANAIS (Annual Modulation with NaI(Tl)
Scintillators) experiment aims at the confirmation of the DAMA/LIBRA signal at
the Canfranc Underground Laboratory (LSC). Two NaI(Tl) crystals of 12.5 kg each
produced by Alpha Spectra have been taking data since December 2012. The
complete background model of these detectors and more precisely in the region
of interest will be described. Preliminary background analysis of a new 12.5 kg
crystal received at Canfranc in March 2015 will be presented too. Finally, the
power of anticoincidence rejection in the region of interest has been analyzed
in a 4x 5 12.5 kg detector matrix.Comment: Contributed to the 11th Patras Workshop on Axions, WIMPs and WISPs,
Zaragoza, June 22 to 26, 201
Production and relevance of cosmogenic radionuclides in NaI(Tl) crystals
The cosmogenic production of long-lived radioactive isotopes in materials is
an hazard for experiments demanding ultra-low background conditions. Although
NaI(Tl) scintillators have been used in this context for a long time, very few
activation data were available. We present results from two 12.5 kg NaI(Tl)
detectors, developed within the ANAIS project and installed at the Canfranc
Underground Laboratory. The prompt data taking starting made possible a
reliable quantification of production of some I, Te and Na isotopes with
half-lives larger than ten days. Initial activities underground were measured
and then production rates at sea level were estimated following the history of
detectors; a comparison of these rates with calculations using typical cosmic
neutron flux at sea level and a selected description of excitation functions
was also carried out. After including the contribution from the identified
cosmogenic products in the detector background model, we found that the
presence of 3H in the crystal bulk would help to fit much better our background
model and experimental data. We have analyzed the cosmogenic production of 3H
in NaI, and although precise quantification has not been attempted, we can
conclude that it could imply a very relevant contribution to the total
background below 15 keV in NaI detectors.Comment: Proceedings of the Low Radioactivity Techniques 2015 workshop, March
2015, Seattle (US
Nutritional and bioactive characteristics of Ayocote bean (Phaseolus coccienus L): an underutilized legume harvasted in Mexico
Artículo en revista indizadaNutritional composition, content of phenolic compounds and antioxidant properties of the four Mexican varieties of Ayocote beans (Phaseolus coccineus L.) were studied. Ayocote beans were found to be a promising source of proteins, carbohydrates, fibre and minerals. Sucrose (55.6–62.2 g/kg) and stachyose (24–24.4 g/kg) were considered as the major sugar and oligosaccharide, respectively. Glutamic acid was the most abundant amino acid (32.2 to 35.8 g/kg), while cysteine was present at the lowest concentration (2.3–2.4 g/100 kg). Purple variety contains the highest amount of total phenolic compounds (2075.9 mg GAE/kg), total flavonoids (1612.9 mg QE/kg) and total anthocyanins (1193.2 mg CGE/kg). This variety also exhibited the most effective antioxidant activities, which were evaluated by DPPH (17,040 μmol TE/kg) and ORAC (51,620 μmol TE/kg). The results obtained reveal a high potential for wider use of Ayocote bean as a remarkable source of bioactive compounds and health-promoting food
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