Evaluación biológica de un proceso avanzado de oxidación para la remoción de contaminantes de un efluente hospitalario

Tesis de doctoradoEl incremento de sustancias químicas usadas por el hombre, ha traído consigo severos daños a los ecosistemas. Existe una variedad de compuestos presentes en el medio ambiente, sin embargo, destacan los contaminantes emergentes. Estos, son compuestos de los cuales se sabe relativamente poco o nada acerca de su presencia e impacto en los distintos compartimentos ambientales, razón por la cual aún no han sido regulados, además, la disponibilidad de métodos para su análisis es nula o limitada. Otra característica de estas sustancias, es que debido a su elevada producción y consumo, son introducidos constantemente en el medio ambiente, asimismo, no necesitan ser persistentes para ocasionar efectos negativos en los organismos que estén en contacto con ellos, por lo anterior, su estudio es una línea prioritaria de investigación. Los fármacos pueden ingresar al medio ambiente por las descargas industriales (industria farmacéutica) y municipales (efluentes de hospitales y casas), sin embargo, generalmente estos efluentes no reciben tratamientos correctos para la remoción de estos compuestos, ya que las plantas tratadoras de aguas residuales, no poseen las características necesarias para su remoción, incluso, en algunos casos, se pueden generar metabolitos más tóxicos que los compuestos originales. Los efluentes hospitalarios han despertado especial interés debido a su composición, la cual incluye productos farmacéuticos, desinfectantes, detergentes y metales Debido a que los métodos tradicionales de tratamiento de aguas residuales, no son suficientemente eficientes para la remoción de contaminantes emergentes, han surgido nuevas tecnologías conocidas como “procesos avanzados de oxidación” (AOP´s por sus siglas en inglés), éstos logran la mineralización de la materia orgánica y han demostrado su eficacia mediante parámetros físico-químicos, sin embargo, debido a que generan gran cantidad de radicales libres, pueden resultar dañinos para los seres vivos, por lo que es necesario comprobar la eficiencia biológica de estos tratamientos. Los procesos fotocatalíticos de TiO2 con la adición de Sn, pueden ser una alternativa para el tratamiento de efluentes hospitalarios, pues han demostrado ser útiles para la degradación de contaminantes pero existe muy poca información sobre sus efectos en organismos vivos. El propósito del presente proyecto fue evaluar la eficiencia biológica de un proceso avanzado de oxidación, siendo este, un tratamiento vía procesos fotocatalítico empleando TiO2 adicionado con Sn para la remoción de contaminantes del efluente hospitalario de la unidad de medicina familiar del IMSS No. 222. Lo anterior se logró mediante la comparación de los resultados de toxicidad aguda y sub-letal antes y después del tratamiento antes mencionado empleado como bioindicador al anfípodo Hyalella azteca. La toxicidad aguda se determinó mediante el valor de concentración letal 50 (CL50) y la toxicidad sub-crónica será mediante la evaluación de la batería de estrés oxidativo (Lipoperoxidación, contenido de proteínas carboniladas, hidroperóxidos y las enzimas antioxidantes superóxido dismutasa y catalasa).Consejo Nacional de Ciencia y Tecnologí

Acrylamide acute neurotoxicity in adult zebrafish

Un articulo indexadoAcute exposure to acrylamide (ACR), a type-2 alkene, may lead to a ataxia, skeletal muscles weakness and numbness of the extremities in human and laboratory animals. In the present manuscript, ACR acute neurotoxicity has been characterized in adult zebrafish, a vertebrate model increasingly used in human neuropharmacology and toxicology research. At behavioral level, ACR-treated animals exhibited “depression-like” phenotype comorbid with anxiety behavior. At transcriptional level, ACR induced down-regulation of regeneration-associated genes and up-regulation of oligodendrocytes and reactive astrocytes markers, altering also the expression of genes involved in the presynaptic vesicle cycling. ACR induced also significant changes in zebrafish brain proteome and formed adducts with selected cysteine residues of specific proteins, some of them essential for the presynaptic function. Finally, the metabolomics analysis shows a depletion in the monoamine neurotransmitters, consistent with the comorbid depression and anxiety disorder, in the brain of the exposed fish.Conacy

DNA damage and cytotoxicity induced on common carp by pollutants in water from an urban reservoir. Madín reservoir, a case study

Artículo científicoMadín Reservoir provides a substantial amount of drinking water to two municipalities close to Mexico City metropolitan area. However, it receives untreated wastewater discharges from domestic sources in the towns of Nuevo Madín and others, as well as diverse pollutants which are hauled by the Río Tlal- nepantla from its upper reaches, so that the xenobiotics in the reservoir are highly diverse in terms of type and quantity. Previous studies showed that MR is contaminated with xenobiotics such as Al, Hg and Fe, as well as NSAIDs, at concentrations exceeding the limits established for aquatic life protection. These pollutants have been shown to induce oxidative stress on Cyprinus carpio and may therefore also damage the genetic material of exposed organisms, eliciting cytotoxicity as well. The present study aimed to determine the genotoxicity and cytotoxicity induced on blood, liver and gill of C. carpio by the pollutants present in MR water. Specimens were exposed to water from five sampling sites and the following biomarkers were evaluated: DNA damage by comet assay, frequency of micronuclei, apoptosis by TUNEL assay and caspase-3 activity. Significant increases relative to the control group (P < 0.05) were found with all biomarkers in all tissues evaluated, with the level of damage differing between sampling sites. In conclusion, pollutants present in MR water are genotoxic and cytotoxic to C. carpio, and this sentinel species, coupled with the biomarkers evaluated herein, is a reliable tool for assessing the health risk to wildlife posed by exposure to pollutants in freshwater bodies.Consejo Nacional de Ciencia y Tecnología (CONACyT-Mexico, Proj- ect 181541), and the Secretaría de Investigacio n y Posgrado, Insti- tuto Polite cnico Nacional (SIP-IPN, proyecto 20160871)

Photo-Fenton Treatment of a Pharmaceutical Industrial Ef!uent Under Safe pH Conditions

This chapter aims to present the effect of treating a pharmaceutical industrial effluent by photo-Fenton catalyzed with a Fe-pillared bentonite. XRD proved the pillaring process successful, and by N2 physisorption, it was established that the specific surface area of bentonite (34 m2 /g) increased to 277 m2 /g and pore volume increased from 0.058 to 0.106 cm3 /g. Active Fe species were identified by Mössbauer spectroscopy. The effect of reaction variables such as catalyst loading, pH, H2O2 concentration, and initial concentration of total organic carbon (TOC) is also presented. It was concluded that to reach near 100% mineralization, an acidic pH (2.7) should be observed. A high mineralization under these conditions, how- ever, does not directly correlate with a low toxicity. Actually, the oxidative stress biomarkers only decreased when pH was not modified (pH 1⁄4 8) albeit the attained mineralization was only 51%. It is worth noticing that the use of pillared clays allows carrying out photo-Fenton treatment under pH conditions other than acidic. The synthesized catalyst exhibited magnetism and this can be used for an easier recovery

Reduction of the Oxidative Stress Status Using Steviol Glycosides in a Fish Model (Cyprinus carpio)

Artículo científicoSteviol glycosides are sweetening compounds from the Stevia rebaudiana Bertoni plant. This product is considered safe for human consumption and was approved as a food additive by the Food and Drugs Administration (FDA) and European Food Safety Authority (EFSA). Its effects on the ecosystem have not been studied in depth; therefore, it is necessary to carry out ecotoxicological studies in organisms such as Cyprinus carpio. The present study aimed to evaluate the antioxidant activity by SGs on diverse tissues in C. carpio using oxidative stress (OS) biomarkers. To test the antioxidant activity, carps were exposed to four systems: (1) SGs free 444 control,(2)CCl 0.5mL/kg,(3)SGs1g/L,and(4)CCl 0.5mL/kg+SGs1g/Lat96h.Thefollowingbiomarkerswereanalyzed: lipoperoxidation (LPX), hydroperoxide content (HPC), and protein carbonyl content (PCC), as well as antioxidant activity of superoxide dismutase (SOD) and catalase (CAT). It was found that both (3 and 4) systems’ exposure decreases LPX, CHP, PCC, SOD,andCATwithrespecttotheCCl system.TheresultsofthisstudydemonstratethattheconcentrationsofSGsusedarenot capable of generating oxidative stress and, on the contrary, would appear to induce an antioxidant effect

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Las Ciénegas del Lerma, importancia de este cuerpo de agua y los efectos de la contaminación

Las ciénegas del río Lerma son el hogar de una gran variedad de especies animales y vegetales de gran importancia para el equilibrio ecológico; sin embargo, la contaminación ha provocado la muerte de muchas de ellas. Este artículo pretende con concientizar sobre la necesidad de recuperar esta área natural, incluso calificada como protegida

Development of a vibrational startle response assay for screening environmental pollutants and drugs impairing predator avoidance.

Articulo indexadoThe present paper describes the vibrational startle response assay (VSRA), a new robust, simple and automated in vivo medium- to high-throughput procedure for assessment of the escape response and its habituation in zebrafish larvae. Such behaviors enable fish larvae to escape from predator strikes in aquatic ecosystems. The assay is based on measuring the distance moved by each larva during the startle response evoked by repetitive vibrational stimuli. The iterative reduction observed in the response to a series of tapping stimulus in VSRA met the main criteria of habituation. Subsequently, the analysis of concordance using a battery of neuroactive compounds modulating different neurotransmitter systems demonstrated that the results of VSRA are highly predictive of the effects on other vertebrates. Finally, as a proof of concept, VSRA was used to test two relevant environmental pollutants at different concentrations. The results demonstrated that VSRA is suitable for concentration-response analysis of environmental pollutants, opening the possibility to determine the potency and the associated hazard of impaired escape response for the different compounds. Therefore, we suggest that VSRA could be a valuable tool for screening of chemical compounds capable of compromising predator avoidance behavior.Conacy

Development of a vibrational startle response assay for screening environmental pollutants and drugs impairing predator avoidance

The present paper describes the vibrational startle response assay (VSRA), a new robust, simple and automated in vivo medium- to high-throughput procedure for assessment of the escape response and its habituation in zebrafish larvae. Such behaviors enable fish larvae to escape from predator strikes in aquatic ecosystems. The assay is based on measuring the distance moved by each larva during the startle response evoked by repetitive vibrational stimuli. The iterative reduction observed in the response to a series of tapping stimulus in VSRA met the main criteria of habituation. Subsequently, the analysis of concordance using a battery of neuroactive compounds modulating different neurotransmitter systems demonstrated that the results of VSRA are highly predictive of the effects on other vertebrates. Finally, as a proof of concept, VSRA was used to test two relevant environmental pollutants at different concentrations. The results demonstrated that VSRA is suitable for concentration-response analysis of environmental pollutants, opening the possibility to determine the potency and the associated hazard of impaired escape response for the different compounds. Therefore, we suggest that VSRA could be a valuable tool for screening of chemical compounds capable of compromising predator avoidance behavior. © 2018 Elsevier B.V.This work was supported by the Spanish Government ( CTM2017-83242-R ) and by the NATO SfP project MD.SFPP 984777 . M.F acknowledges financial support from the Beatriu de Pinós programme (grant No: 2016 BP 00233 ) provided by the Secretariat of Universities and Research department of the Ministry for Business and Knowledge, Catalonia Government. K.A.N.L was supported by the grant 291212 from the Mixed Fund programme for mobility (CONACYT-2017). J.B acknowledges financial support from Bouygues Foundation 's bursary, in the frame of the Erasmus Traineeship ( FTOULOUS03 ).Peer reviewe

Reduction of the Oxidative Stress Status Using Steviol Glycosides in a Fish Model (Cyprinus carpio)

Artículo científicoSteviol glycosides are sweetening compounds from the Stevia rebaudiana Bertoni plant. This product is considered safe for human consumption and was approved as a food additive by the Food and Drugs Administration (FDA) and European Food Safety Authority (EFSA). Its effects on the ecosystem have not been studied in depth; therefore, it is necessary to carry out ecotoxicological studies in organisms such as Cyprinus carpio. The present study aimed to evaluate the antioxidant activity by SGs on diverse tissues in C. carpio using oxidative stress (OS) biomarkers. To test the antioxidant activity, carps were exposed to four systems: (1) SGs free 444 control,(2)CCl 0.5mL/kg,(3)SGs1g/L,and(4)CCl 0.5mL/kg+SGs1g/Lat96h.Thefollowingbiomarkerswereanalyzed: lipoperoxidation (LPX), hydroperoxide content (HPC), and protein carbonyl content (PCC), as well as antioxidant activity of superoxide dismutase (SOD) and catalase (CAT). It was found that both (3 and 4) systems’ exposure decreases LPX, CHP, PCC, SOD,andCATwithrespecttotheCCl system.TheresultsofthisstudydemonstratethattheconcentrationsofSGsusedarenot capable of generating oxidative stress and, on the contrary, would appear to induce an antioxidant effect