RESUMEN
The risk of the use of toxic chemicals for unlawful acts has been a matter of concern for different governments and multilateral agencies. The Organisation for the Prohibition of Chemical Weapons (OPCW), which oversees the implementation of the Chemical Weapons Convention (CWC), considering recent events employing chemical warfare agents as means of assassination, has recently included in the CWC "Annex on Chemicals" some organophosphorus compounds that are regarded as acting in a similar fashion to the classical G- and V-series of nerve agents, inhibiting the pivotal enzyme acetylcholinesterase. Therefore, knowledge of the activity of the pyridinium oximes, the sole class of clinically available acetylcholinesterase reactivators to date, is plainly justified. In this paper, continuing our research efforts in medicinal chemistry on this class of toxic chemicals, we synthesized an A-230 nerve agent surrogate and applied a modified Ellman's assay to evaluate its ability to inhibit our enzymatic model, acetylcholinesterase from Electrophorus eel, and if the clinically available antidotes are able to rescue the enzyme activity for the purpose of relating the findings to the previously disclosed in silico data for the authentic nerve agent and other studies with similar A-series surrogates. Our experimental data indicates that pralidoxime is the most efficient compound for reactivating acetylcholinesterase inhibited by A-230 surrogate, which is the opposite of the in silico data previously disclosed.
Asunto(s)
Acetilcolinesterasa , Sustancias para la Guerra Química , Inhibidores de la Colinesterasa , Reactivadores de la Colinesterasa , Agentes Nerviosos , Oximas , Compuestos de Piridinio , Oximas/farmacología , Acetilcolinesterasa/metabolismo , Reactivadores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/toxicidad , Compuestos de Piridinio/farmacología , Sustancias para la Guerra Química/toxicidad , Agentes Nerviosos/toxicidad , Compuestos de Pralidoxima/farmacología , Compuestos Organotiofosforados/toxicidad , Animales , Antídotos/farmacologíaRESUMEN
Pesticides has transformed the agricultural industry, primarily by enhancing productivity. However, the indiscriminate use of such compounds can adversely affect human health and disrupt ecosystem balance. Limited knowledge exists regarding the removal of these compounds from water, particularly for organophosphate pesticides when employing conventional treatment technologies. Therefore, this study aimed to assess the removal of acephate (ACE) and methamidophos (MET) - considered priority pesticides in Brazil - from waters with high and low turbidity during the clarification process carried out with aluminum sulfate (AS) and ferric chloride (FC), either alone or combined with powdered activated carbon (PAC) adsorption. All water samples were submitted to solid phase extraction (SPE C18 cartridges) prior to acephate and methamidophos analysis by HPLC MS/MS. The clarification process with either AS or FC coagulant did not efficiently remove acephate or methamidophos and maximum average removal (27 %) was observed with waters of high turbidity when using ferric chloride as coagulant. Addition of mineral PAC was also ineffective for removing both pesticides. However, the use of vegetable PAC (10 mg/L) resulted in better removal percentages, up to 80%, but only for methamidophos. The limited removal rates were attributed to the high hydrophilicity of acephate and methamidophos, along with their neutral charge at coagulation pH. These factors hinder the interaction of such organophosphorus pesticides with the flocs formed during coagulation as well as with PAC surface.
Asunto(s)
Compuestos Organotiofosforados , Fosforamidas , Contaminantes Químicos del Agua , Purificación del Agua , Compuestos Organotiofosforados/química , Contaminantes Químicos del Agua/análisis , Adsorción , Purificación del Agua/métodos , Compuestos Férricos/química , Brasil , Compuestos de Alumbre/química , Extracción en Fase Sólida/métodos , Plaguicidas , ClorurosRESUMEN
Environmental contamination by pesticides is a recurrent problem, and a way to minimize its impacts and provide the reduction of contaminants already in the environment is a challenge. In this context, porous materials such as metal-organic frameworks (MOFs) have gained prominence. MOFs can carry the pesticide when physically or chemically interacting with its pore sites, enabling pesticide capture. However, evaluating the best MOF to maximize the process is an important step that can be performed under computer simulation. This work used grand canonical Monte Carlo simulations to assess the interaction between glyphosate, atrazine, acephate, and dichlorodiphenyltrichloroethane pesticides with the structures of IRMOF-1, IRMOF-8, IRMOF-10, and IRMOF-16. These MOFs present several organic unit types, which generate different pore volumes with similar chemical environment. For glyphosate, atrazine, and acephate, a direct relationship was shown between the pore volume and the amount of captured pesticide, which is a direct contribution from the strong interaction between the pesticides. Higher pore volumes maximize glyphosate, atrazine, and acephate capture. Otherwise, for dichlorodiphenyltrichloroethane, the larger the pore volume, the smaller the amount of pesticide is loaded. The interaction between all pesticides and IRMOFs is mainly governed by van der Waals contribution, being more pronounced for glyphosate, atrazine, and acephate molecules.
Asunto(s)
Atrazina , Estructuras Metalorgánicas , Plaguicidas , Simulación por Computador , Electrónica , Estructuras Metalorgánicas/química , Compuestos Organotiofosforados , FosforamidasRESUMEN
The presence and use of carbamate and organophosphate pesticides with agricultural and urban purposes in Colombia has been justified for pest control. However, these substances pose a national problem because of their toxic nature, which is associated with accidental poisoning or even with homicides or suicides related to acute fatal poisoning. This study aims to develop and to validate an analytical methodology for the determination of the aldicarb, carbofuran and methamidophos pesticides in blood through liquid chromatography--tandem mass spectrometry (LC-MS-MS). To this end, the method for extracting pesticides from the blood was developed, the conditions of LC were defined, the instrumental system MS-MS was optimized and the bioanalytical methodology was validated. This methodology proved to be selective, precise, accurate and linear in the concentration range from 0.10 to 5.0 µg/mL, with a limit of detection of 0.020 µg/mL for aldicarb and carbofuran and 0.050 µg/mL for methamidophos, recovery between 90% and 102%, and stability at room temperature and in the autosampler between 80% and 120%. The analytical methodology was applied to 34 forensic cases. Carbofuran was found at a concentration ranging from 0.020 to >5.0 µg/mL, aldicarb was found at a concentration ranging from 0.10 to 2.5 µg/mL and methamidophos was found at a concentration >5.0 µg/mL. In 62% of the cases, the pesticides under study were used to commit suicide. Necropsy findings of pesticide poisoning are non-specific. Therefore, toxicological blood analysis provides significant information at the forensic level, and the analytical method validated represents a sensitive, fast and reliable analysis with little solvent consumption of a small sample amount, so it is suitable for routine application in fatal pesticide poisonings.
Asunto(s)
Carbofurano , Suicidio , Aldicarb , Cromatografía Liquida , Humanos , Compuestos Organotiofosforados , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en TándemRESUMEN
AIMS: Investigate the involvement of Hydrogen sulfide (H2S) in inflammatory parameters and intestinal morphology caused by cholera toxin (CT) in mice. MAIN METHODS: Mice were subjected to the procedure of inducing diarrhea by CT in the isolated intestinal loop model. The intestinal loops were inoculated with H2S donor molecules (NaHS and GYY 4137) or saline and CT. To study the role of EP2 and EP4 prostaglandin E2 (PGE2) receptors in the H2S antisecretory effect, PAG (DL-propargylglycine - inhibitor of cystathionine-γ-lyase (CSE)), PF-04418948 (EP2 antagonist) and ONO-AE3-208 (EP4 antagonist) were used. The intestinal loops were evaluated for intestinal secretion, relation of the depth of villi and intestinal crypts, and real-time PCR for the mRNA of the CXCL2, IL-6, NOS-2, IL-17, NF-κB1, NF-κBIA, SLC6A4 and IFN-γ genes. KEY FINDINGS: H2S restored the villus/crypt depth ratio caused by CT. NaHS and GYY 4137 increased the expression of NF-κB1 and for the NF-κBIA gene, only GYY 4137 increased the expression of this gene. The increased expression of NF-κB inhibitors, NF-κB1 and NF-κBIA by H2S indicates a possible decrease in NF-κB activity. The pretreatment with PAG reversed the protective effect of PF-04418948 and ONO-AE3-208, indicating that H2S probably decreases PGE2 because in the presence of antagonists of this pathway, PAG promotes intestinal secretion. SIGNIFICANCE: Our results point to a protective activity of H2S against CT for promoting a protection of villus and crypt intestine morphology and also that its mechanism occurs at least in part due to decreasing the activity of NF-κB and PGE2.
Asunto(s)
Diarrea/inducido químicamente , Diarrea/metabolismo , Dinoprostona/metabolismo , Sulfuro de Hidrógeno/farmacología , Mucosa Intestinal/patología , FN-kappa B/metabolismo , Animales , Toxina del Cólera , Femenino , Perfilación de la Expresión Génica , Masculino , Ratones , Morfolinas/farmacología , Compuestos Organotiofosforados/farmacología , Subtipo EP2 de Receptores de Prostaglandina E/metabolismo , Subtipo EP4 de Receptores de Prostaglandina E/metabolismoRESUMEN
Acute toxicity of organophosphate (OPs) pesticides is a public health problem. The adverse effects are associated with the inhibition and aging of nervous system B-esterases such as acetyl cholinesterase (AChE) and neuropathic target esterase (NTE). Treatment based on A-esterases such as mammal serum paraoxonase-1 has been suggested. This ex vivo study shows the Cu2+-dependent hydrolysis of trichloronate (TCN), a racemic organophosphonothioate insecticide, in human and domestic mammal serum (dog, goat, pig, sheep and cow). Ca2+-dependent (2.5 mM) or EDTA-resistant (5 mM) activity (1-6%) was not significant (p>0.05) in all samples, except goat serum and its albumin, which showed higher levels of TCN hydrolysis (38-58%) than other mammals with 100 and 300 µM copper sulfate at physiological conditions for 60 min. Goat serum albumin (GSA) showed significant (pË0.05) stereoselective hydrolysis (+)-TCN Ë (-)-TCN (45% versus 33%). This suggests that GSA is the protein responsible for Cu2+-dependent TCNase activity in goat serum. This is the first report on Cu2+-dependent A-esterase activity in mammalian tissues. This goat serum cuproprotein could be considered as an alternative in future biotechnological applications including enantiomeric synthesis, bioremediation and antidotal treatment of organophosphonothioate pesticide poisoning.
Asunto(s)
Insecticidas/química , Compuestos Organotiofosforados/química , Hidrolasas Diéster Fosfóricas/química , Albúmina Sérica/química , Animales , Cobre/química , Euterios , Hidrólisis , Hidrolasas Diéster Fosfóricas/sangre , Estereoisomerismo , PavosRESUMEN
The determination of necrophagous fly specie's development time is considered an accurate method for estimating postmortem interval (PMI). However, pesticides and other chemicals can alter the flies' life cycle, inducing errors in PMI estimation. Thus, this work aimed to evaluate the effect of different doses of Terbufos (Organophosphates) on the temporal dispersion pattern and development of immature dipterans associated with decaying rat carcasses. For this, 150 g female Wistar rats received, via gavage, 200 µl of Terbufos (5 or 10 mg/kg) or distilled water (control) and, after 30 min of administration, the animals were euthanized and distributed in suspended traps to decompose under environmental conditions. The dispersing immatures were collected daily, and their development time was monitored until the emergence of adult flies. After data analysis, it was observed that Terbufos altered 1) the temporal pattern of larval dispersion; 2) the composition and structure of the colonizing assemblage (emerged adults); 3) species' development time, accelerating or delaying their cycle, depending on the dose used; and 4) the califorids and sarcophagids emergence rate, increasing the mortality of pupae from intoxicated carcasses. Thus, this work demonstrates experimentally that Terbufos directly influences the development of flies with forensic potential and discusses the implications for PMI estimation, which can assist in future investigative processes with suspected poisoning by this organophosphate.
Asunto(s)
Calliphoridae/efectos de los fármacos , Entomología Forense , Insecticidas/toxicidad , Muscidae/efectos de los fármacos , Compuestos Organotiofosforados/toxicidad , Sarcofágidos/efectos de los fármacos , Animales , Cadáver , Calliphoridae/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Femenino , Muscidae/crecimiento & desarrollo , Ratas , Ratas Wistar , Sarcofágidos/crecimiento & desarrolloRESUMEN
A monitoring study was carried out in three agriculturally influenced microcatchments in Costa Rica during 2012-2014, for pesticides and water quality parameters. A total of 42 pesticides were analyzed, detecting the following in water samples: two herbicides (oxyfluorfen, diuron), four insecticides (carbofuran, chlorpyrifos, oxamyl, ethion), and two fungicides (thiabendazole, carbendazim); while in sediment samples only the insecticides, chlorpyrifos and cypermethrin were found. Water quality was also assessed by the Canadian Council of Ministers of the Environment Water Quality Index and the National Sanitation Water Quality Index, the first one classified most of the sampling point as marginal and poor quality while the second one classified most of them as good quality, the most affected parameters were nitrate, phosphorous, suspended solids and organic matter content. The results suggest that the water quality in the microcatchments seems to be affected by the nearby agricultural and urban activities in the region.
Asunto(s)
Monitoreo del Ambiente , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Agricultura , Canadá , Carbamatos , Cloropirifos , Diurona , Herbicidas/análisis , Insecticidas/análisis , Compuestos Organotiofosforados , Ríos , Estados Unidos , Calidad del AguaRESUMEN
Methamidophos (MET) is a pesticide that has toxic properties, including effects on fertility. This study aimed to assess the joint action of treatment time and exposure to methamidophos on the male reproductive system. MET was orally administered to adult male Swiss mice at a dose of 0.004 mg.kg-1 for 15 and 50 consecutive days. The following parameters were evaluated: weight of reproductive organs, spermatogenesis, sperm and Sertoli cell count, daily sperm production and sperm transit time. Short-term exposure to methamidophos induced a decrease in epididymal weight. The frequency of stages V-VI of spermatogenesis increased and the frequency of stage IX decreased. In the epididymis, sperm transit time (caput/corpus) was reduced and the relative sperm number (cauda) increased. Long-term exposure induced an increase in the frequencies of stages I-IV and V-VI and decreased the stages VII-VIII and IX. The number of Sertoli cells with evident nucleoli was reduced in both exposures. These results confirm the reproductive toxicity of MET.
Asunto(s)
Insecticidas/administración & dosificación , Compuestos Organotiofosforados/administración & dosificación , Espermatogénesis/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Animales , Epidídimo/efectos de los fármacos , Masculino , Ratones , Tamaño de los Órganos/efectos de los fármacos , Reproducción/efectos de los fármacos , Células de Sertoli/efectos de los fármacos , Recuento de Espermatozoides , Testículo/efectos de los fármacosRESUMEN
In the present work, we performed a complementary quantum mechanical (QM) study to describe the mechanism by which deprotonated pralidoxime (2-PAM) could reactivate human (Homo sapiens sapiens) acetylcholinesterase (HssAChE) inhibited by the nerve agent VX. Such a reaction is proposed to occur in subsequent addition-elimination steps, starting with a nucleophile bimolecular substitution (SN2) mechanism through the formation of a trigonal bipyramidal transition state (TS). A near attack conformation (NAC), obtained in a former study using molecular mechanics (MM) calculations, was taken as a starting point for this project, where we described the possible formation of the TS. Together, this combined QM/MM study on AChE reactivation shows the feasibility of the reactivation occurring via attack of the deprotonated form of 2-PAM against the Ser203-VX adduct of HssAChE.
Asunto(s)
Acetilcolinesterasa/efectos de los fármacos , Compuestos Organotiofosforados/farmacología , Compuestos de Pralidoxima/farmacología , Acetilcolinesterasa/química , Dominio Catalítico , Humanos , Conformación Molecular , Simulación de Dinámica Molecular , Compuestos de Pralidoxima/química , Protones , Teoría Cuántica , Serina/químicaRESUMEN
AIMS: The present study aims to determine the phototoxic and haemolytic activity of organophosphorus. The use of alternative in vitro assays with human erythrocytes is suggested to predict the polluting effect of these products on health. METHODOLOGY: Human erythrocytes from Toluca Blood Bank were used. Sodium dodecyl sulfate was employed as a positive control. Additionally, the haemolysis percentage of three organophosphate (Acetate, Chlorpyrifos, Malathion, Methamidophos, Methyl Parathion) induced photo haemolysis formulated with surfactants on a concentration of 2 x 109 erythrocytes were evaluated. Finally, the products were classified as irritant or phototoxic. RESULTS: Results showed that the HC50 red blood cells were similar for each organophosphate (Malathion and Methamidophos) indicating very irritant action with ratio classification (L/D) of 0.041 and 0.053, respectively. On the other hand, Chlorpyrifos was classified as an irritant with L/D= 0.14. On the other hand, the HC50 obtained photo hemolysis assays irradiated red blood cells was similar for each organophosphate (Acetate, Chlorpyrifos, Malathion, Methamidophos, Methyl Parathion) indicating no phototoxic action. CONCLUSION: As a conclusion, it can be said that the parameters of haemolysis and denaturation of proteins are good indicators to classify organophosphorus formulated with surfactants as irritating or phototoxic.
Asunto(s)
Eritrocitos/metabolismo , Hemólisis/efectos de los fármacos , Hemólisis/efectos de la radiación , Compuestos Organofosforados/química , Fotoquimioterapia/métodos , Tensoactivos/química , Cloropirifos/química , Humanos , Técnicas In Vitro , Malatión/química , Intoxicación por Organofosfatos , Compuestos Organotiofosforados/química , Desnaturalización Proteica/efectos de los fármacosRESUMEN
Acephate is an organophosphate insecticide that disrupts the endocrine system and impairs the male reproductive system. Thus, the aim of the present study was to evaluate whether exposure to acephate during maternal gestation and lactation histologically damages the testes of male Wistar rats in adulthood. For this study, adult Wistar rats were divided into the following groups: ACE-mother, (2.5 mg/kg/bw, gestational day (GD) 7 to postnatal day (PND) 21) and oil-mother (corn oil (control), GD 7 to PND 21). The male offspring (PND 90) were euthanized, and the prostates and testes were collected and weighed. The testes were utilized for histopathological analyses and to determine the sperm count. A spermatogenesis kinetic analysis revealed an increased number of seminiferous tubules in stages I-VI in the ACE-mother group. Additionally, we observed a decrease in the epithelium and the diameters of the evaluated seminiferous tubules and in the number of Sertoli cells in the group exposed to acephate. The sperm count analysis showed no difference between the groups. We conclude that maternal exposure to the pesticide acephate did not affect testicular function, but led to the impairment of testicular development and morphology of the tissue in adulthood.
Asunto(s)
Insecticidas/toxicidad , Compuestos Organotiofosforados/toxicidad , Fosforamidas/toxicidad , Testículo/crecimiento & desarrollo , Animales , Femenino , Cinética , Lactancia , Masculino , Exposición Materna , Tamaño de los Órganos , Embarazo , Ratas , Ratas Wistar , Testículo/efectos de los fármacos , Pruebas de ToxicidadRESUMEN
A rapid analysis of acephate, chlorpyrifos, and cyazofamid in tomato peels during pre-harvest intervals using paper spray ionization mass spectrometry (PSI-MS) has been demonstrated. LODs of 0.01 ppm and LOQs of 0.03 ppm were achieved. Relative standard deviations were below 9%, and recoveries close to 100%. For pesticides monitoring, samples were separated into stored and field groups. Stored group contained fruits that were harvested and stored at low temperature during the pre-harvest interval, and the field group contained fruits that were on the agricultural field over the pre-harvest interval. The decrease in pesticide amounts was lower for the stored samples. At the end of the pre-harvest intervals, acephate, chlorpyrifos, and cyazofamid were determined at 0.86, 0.96, and 0.23 ppm in the stored group, and at 0.26, 0.37, and 0.09 ppm in the field group, respectively. This work demonstrates the utility of PSI-MS for performing rapid quality control of fruit harvesting.
Asunto(s)
Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Plaguicidas/análisis , Solanum lycopersicum/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Almacenamiento de Alimentos , Frutas/química , Imidazoles/análisis , Compuestos Organotiofosforados/análisis , Fosforamidas , Sulfonamidas/análisisRESUMEN
Intensive use of chemical acaricides for the control of cattle ticks (Rhipicephalus microplus) has led to the development of multiple acaricide resistance in Colombia. The present study aimed to characterize, using toxicological bioassays and molecular biology techniques, the resistance profile of a tick strain isolated from the Arauca state, Northeast Colombia. Commercial acaricides were used in adult immersion tests to determine its in vitro efficacies. Deltamethrin showed very low activity (4-7.3%), a mixture of cypermethrin and chlorpyrifos had intermediate efficacy (64-75.2%), and ethion presented the highest activity (88.5-100%). A colony (Arauquita strain) was established and larval immersion tests confirmed high resistance level to deltamethrin (241-fold) and susceptibility to ivermectin. A quantitative polymerase chain reaction-high resolution melt technique was used to identify single nucleotide polymorphisms (SNPs) in the para-sodium channel gene. All of the genotyped individuals were mutant, presenting one (n = 7), two (n = 7) or three (n = 9) SNPs previously associated with pyrethroid resistance. Sequencing revealed a novel mutation (F712L), that was found for the first time in R. microplus ticks from South America. This is the first description of mutations associated with pyrethroid resistance in R. microplus from Colombia. The acaricide resistance pattern found in the Arauquita strain is similar to other parts of Colombia.
Asunto(s)
Acaricidas/farmacología , Resistencia a Medicamentos/genética , Nitrilos/farmacología , Piretrinas/farmacología , Rhipicephalus/efectos de los fármacos , Animales , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/metabolismo , Cloropirifos/farmacología , Colombia , Femenino , Larva/efectos de los fármacos , Larva/genética , Larva/crecimiento & desarrollo , Compuestos Organotiofosforados/farmacología , Rhipicephalus/genética , Rhipicephalus/crecimiento & desarrollo , Canales de Sodio/genética , Canales de Sodio/metabolismoRESUMEN
This study explored the potential association between chronic exposure to pesticide mixtures including paraquat and respiratory outcomes among Colombian farmers. Sociodemographic and occupational data, respiratory symptoms and spirometric data were collected. Paraquat in spot urine samples were quantified with solid-phase extraction high-performance liquid chromatography. Multiple Poisson regressions with robust variance were used to determine factors associated with respiratory outcomes. Profiles of pesticide mixtures used were identified among 217 farmworkers, but profenofos and methamidophos-based mixtures were more frequent. Chronic paraquat exposure was slightly associated with self-reported asthma (PR: 1.06; 95% CI 1.00 to 1.13). Different pesticide mixtures were associated with flu, thoracic pain, allergic rhinitis, and obstructive pattern in spirometry. Although acute exposure to paraquat is low among Colombian farmers participating in the study, associations between respiratory outcomes and chronic pesticide mixtures exposure including profenofos, methamidophos or glyphosate require further specific studies.
Asunto(s)
Agricultores , Exposición Profesional/efectos adversos , Paraquat/efectos adversos , Plaguicidas/efectos adversos , Enfermedades Respiratorias/epidemiología , Adolescente , Adulto , Anciano , Dolor en el Pecho/epidemiología , Colombia/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Organotiofosfatos/efectos adversos , Compuestos Organotiofosforados/efectos adversos , Paraquat/orina , Rinitis Alérgica , EspirometríaRESUMEN
During this research, chemometric approaches were applied for optimization of the low-temperature partitioning extraction (LTPE) for the simultaneous analysis of the pesticides: acephate, difenoconazole, fenamidone, fluazifop, fluazinam, methamidophos, and thiamethoxam from surface water samples and determination by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry. It was used the 23 full factorial and the Doehlert experimental designs. The extraction technique was optimized by evaluating the effects of the three variables: sample pH, ionic strength (addition of Na2HPO4), and organic solvent volume. Considering the interest to find an optimal condition for all analytes simultaneously, the best extraction parameters found were as follows: pH = 5.33, concentration of Na2HPO4 = 0.0088 mol L-1 and organic phase volume = 4.5 mL. The optimized methodology showed LOD and LOQ levels from 0.33 to 8.13 ng L-1 and from 1.09 to 26.84 ng L-1, respectively. The recovery values ranged from 38.37 and 99.83% and the RSD values varied from 2.33 to 18.92%. The method was applied to surface water analysis sampled in areas with intensive agricultural practices in Ouro Branco City, Minas Gerais, Brazil. The difenoconazole was detected in concentrations between 12.53 and 94.76 ng L-1.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Agua/análisis , Agricultura , Brasil , Compuestos Organotiofosforados , Plaguicidas/química , Fosforamidas , Proyectos de Investigación , TemperaturaRESUMEN
Hydrogen sulfide (H2S) is a vasorelaxant gas with therapeutic potential in several diseases. However, effects of H2S donors in hypertensive pregnancy complicated by feto-placental growth restriction are unclear. Therefore, we aimed to examine and compare the effects of fast-releasing H2S donor (sodium hydrosulfide-NaHS) and slow-releasing H2S donor (GYY4137) in hypertension-in-pregnancy. Pregnant rats were distributed into four groups: normal pregnancy (Norm-Preg), hypertensive pregnancy (HTN-Preg), hypertensive pregnancy + NaHS (HTN-Preg + NaHS), and hypertensive pregnancy + GYY4137 (HTN-Preg + GYY). Systolic blood pressure, plasma H2S levels, fetal and placental weights, number of viable fetuses, litter size, and endothelium-dependent vasodilation were examined. Also, oxidative stress was assessed in placenta. We found that GYY4137 attenuated hypertension on gestational days 16 and 18, while NaHS presented antihypertensive effect only on gestational day 18. GYY4137, but not NaHS, increased plasma H2S levels. Greater fetal and placental weights were found with GYY4137 than NaHS treatment. Also, HTN-Preg + NaHS presented further reductions in placental weights when compared to HTN-Preg group. Number of viable fetuses and litter size presented no significant changes. GYY4137 reduced placental oxidative stress caused by hypertension, while greater increases in oxidative stress were found in HTN-Preg + NaHS than HTN-Preg group. Hypertensive pregnancy caused impaired endothelium-dependent vasodilation, while GYY4137 and NaHS treatments blunted endothelial dysfunction. Endothelium-dependent vasodilation was completely blocked by the nitric oxide synthase inhibitor. We conclude that slow-releasing H2S donor GYY4137 is advantageous compared with fast-releasing H2S-donor NaHS to attenuate hypertension-in-pregnancy and to protect against feto-placental growth restriction and oxidative stress.
Asunto(s)
Antihipertensivos/uso terapéutico , Retardo del Crecimiento Fetal/tratamiento farmacológico , Sulfuro de Hidrógeno , Hipertensión/tratamiento farmacológico , Morfolinas/uso terapéutico , Compuestos Organotiofosforados/uso terapéutico , Sulfuros/uso terapéutico , Animales , Antihipertensivos/metabolismo , Antihipertensivos/farmacología , Aorta Torácica/efectos de los fármacos , Aorta Torácica/fisiología , Femenino , Retardo del Crecimiento Fetal/metabolismo , Retardo del Crecimiento Fetal/fisiopatología , Feto/efectos de los fármacos , Sulfuro de Hidrógeno/sangre , Hipertensión/sangre , Hipertensión/metabolismo , Hipertensión/fisiopatología , Tamaño de la Camada/efectos de los fármacos , Malondialdehído/metabolismo , Morfolinas/farmacología , Compuestos Organotiofosforados/farmacología , Placenta/efectos de los fármacos , Embarazo , Ratas Wistar , Sulfuros/farmacologíaRESUMEN
OBJECTIVE: The aim of this study was to determine both the protective effect of rose water (RW) against DNA damage in the tissues of rats exposed to chlorpyrifos-ethyl (CPE) and RW's effect on the oxidant and antioxidant levels in the blood serum and brain tissues of those same rats. METHODS: In this experimental study, 32 mature male wistar albino rats were divided into 4 groups: group I, control; group II, CPE; group III, RW; and group IV, CPE+RW. The parameters of DNA tail intensity and DNA tail moment were analysed in blood samples by comet assay. Glutathione S-transferase (GST), catalase (CAT), and malondialdehyde (MDA) levels in brain tissues were examined. In blood serum, the levels of melatonin (MT) from 3-nitrotyrosine (3-NT) were determined. RESULTS: In the CPE+RW group, the MDA and 3-NT levels in the brain tissues were significantly reduced (p<0.001), while the MT, GST, and CAT levels were significantly higher (p<0.001) compared to those of the CPE group. When the control and RW groups were compared, the CAT, GST, and MT levels were significantly higher (p<0.001) in the RW group, while the MDA and 3-NT levels were significantly lower (p<0.001). CONCLUSION: In rats, RW had positive effects on oxidant damage created by CPE. Both the DNA tail intensity and DNA tail moment in the CPE group were significantly higher (P<0.001) compared to those measures for the control group.
Asunto(s)
Daño del ADN/efectos de los fármacos , Extractos Vegetales/farmacología , Rosa , Agua/farmacología , Animales , Antioxidantes , Cloropirifos , Masculino , Compuestos Organotiofosforados/administración & dosificación , Oxidantes , Ratas , Ratas Wistar , Soluciones/farmacologíaRESUMEN
Biomarkers are frequently used in ecotoxicology as they allow to study toxicant effects happening at low concentrations of exposure. However, most sublethal studies only evaluate cellular biomarkers which lack evident ecological relevance. We used a multibiomarker approach to estimate the toxic effects of ethoprophos, an organophosphate insecticide commonly used in banana plantations, on the tropical fish Astyanax aeneus (Characidae). We measured biomarkers at sub-individual (cellular) and individual (metabolism, behavior) levels and examined relationships among these responses. A sublethal exposure to ethoprophos caused a significant (54%) reduction of brain Cholinesterase (ChE) activity, reflecting the pesticide's high neurotoxicity. However, other biomarkers like oxidative stress, biotransformation reactions, and resting metabolic rate were not affected. Exposure to ethoprophos modified antipredator behaviors such as escape response and detection avoidance (light/dark preference): exposed fish escaped slower from a simulated attack and preferred brighter areas in a novel tank. The relationship between ChE activity and reaction time suggests that pesticide-induced ChE inhibition reduces escape ability in fish. Our results provide evidence that impacts of organophosphate pesticides on fish ecological fitness can occur even with short exposures at very low concentrations.