Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
20 result(s) for "Ethylenethiourea - metabolism"
Sort by:
Assessment of Mancozeb Exposure, Absorbed Dose, and Oxidative Damage in Greenhouse Farmers
Mancozeb (MNZ) is a fungicide commonly employed in many countries worldwide. This study assesses MNZ absorption dynamics in 19 greenhouse farmers, specifically following dermal exposure, aiming to verify the efficacy of both preventive actions and protective equipment. For data collection, a multi-assessment approach was used, which included a survey to record study population features. MNZ exposure was assessed through the indirect measurement of ethylene thiourea (ETU), widely employed as an MNZ biomarker. The ETU concentration was measured with the patch method, detecting environmental ETU trapped in filter paper pads, applied both on skin and working clothes, during the 8 h work shift. Urine and serum end-of-shift samples were also collected to measure ETU concentrations and well-known oxidative stress biomarkers, respectively, namely reactive oxygen metabolites (ROMs), advanced oxidation protein products (AOPPs), and biological antioxidant potential (BAP). It was observed that levels of ETU absorbed and ETU excreted were positively correlated. Additionally, working clothes effectively protected workers from MNZ exposure. Moreover, following stratification of the samples based on the specific working duty (i.e., preparation and spreading of MNZ and manipulation of MNZ-treated seedlings), it was found that the spreading group had higher ETU-related risk, despite lower chronic exposure levels. AOPP and ROM serum levels were higher in MNZ-exposed subjects compared with non-exposed controls, whereas BAP levels were significantly lower. Such results support an increase in the oxidative stress upon 8 h MNZ exposure at work. In particular, AOPP levels demonstrated a potential predictive role, as suggested by the contingency analysis results. Overall, this study, although conducted in a small group, confirms that ETU detection in pads, as well as in urine, might enable assessment of the risk associated with MNZ exposure in greenhouse workers. Additionally, the measurement of circulating oxidative stress biomarkers might help to stratify exposed workers based on their sensitivity to MNZ. Pivotally, the combination of both ETU measurement and biological monitoring might represent a novel valuable combined approach for risk assessment in farmhouse workers exposed to pesticides. In the future, these observations will help to implement effective preventive strategies in the workplace for workers at higher risk, including greenhouse farmers who are exposed to pesticides daily, as well as to clarify the occupational exposure levels to ETU.
Isolation and Characterization of Antagonistic Bacillus Strains Capable to Degrade Ethylenethiourea
In this study, more than 150 bacteria showing antagonistic properties against bacterial and fungal pathogens of the tomato plant were isolated and characterized. The most efficient agents against these phytopathogenic microorganisms belong to the genus Bacillus: the best biocontrol isolates were representatives of Bacillus subtilis, B. mojavensis and B. amyloliquefaciens species. They intensively produced fengycin or/and surfactin depsipeptide antibiotics and also proved to be excellent protease secretors. It was proved, that the selected strains were able to use ethylenethiourea (ETU) as sole nitrogen source. These antagonistic and ETU-degrading Bacillus strains can be applied as biocontrol and also as bioremediation agents.
Method for determination of acephate, methamidophos, omethoate, dimethoate, ethylenethiourea and propylenethiourea in human urine using high-performance liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometry
Because of increasing concern about widespread use of insecticides and fungicides, we have developed a highly sensitive analytical method to quantify urine-specific urinary biomarkers of the organophosphorus pesticides acephate, methamidophos, omethoate, dimethoate, and two metabolites from the fungicides alkylenebis-(dithiocarbamate) family: ethylenethiourea and propylenethiourea. The general sample preparation included lyophilization of the urine samples followed by extraction with dichloromethane. The analytical separation was performed by high-performance liquid chromatography (HPLC), and detection by a triple quadrupole mass spectrometer with and atmospheric pressure chemical ionization source in positive ion mode using multiple reaction monitoring and tandem mass spectrometry (MS/MS) analysis. Two different Thermo-Finnigan (San Jose, CA, USA) triple quadrupole mass spectrometers, a TSQ 7000 and a TSQ Quantum Ultra, were used in these analyses; results are presented comparing the method specifications of these two instruments. Isotopically labeled internal standards were used for three of the analytes. The use of labeled internal standards in combination with HPLC-MS/MS provided a high degree of selectivity and precision. Repeated analysis of urine samples spiked with high, medium and low concentration of the analytes gave relative standard deviations of less than 18%. For all compounds the extraction efficiency ranged between 52% and 63%, relative recoveries were about 100%, and the limits of detection were in the range of 0.001–0.282 ng/ml.
Ethylenebisdithiocarbamates and ethylenethiourea: possible human health hazards
Humans are exposed to ethylenebisdithiocarbamates (EBDCs) from environmental sources. Exposure to EBDCs is chronic for workers in a variety of industries, where EBDCs are used for their properties as slimicides, vulcanization accelerators, antioxidants, and scavengers in waste-water treatment. EBDCs, and particularly the EBDC metabolite ethylenethiourea, have clearly defined, important toxic effects in various animal species, and there is reason to suspect they are carcinogenic in humans. In the absence of definitive information regarding human risk, further studies need to be done. In the interim, regular surveillance of workers with high levels of exposure to EBDCs, with specific attention to markers of thyroid and hepatic pathology, should be considered.
Degradation of ethylenethiourea (ETU) in oxic and anoxic sandy aquifers
Ethylenethiourea is an important degradation product of ethylenebisdithiocarbamate fungicides, which are widely used in different kinds of crops. The ethylenebisdithiocarbamate group includes maneb, zineb and mancozeb. The ethylenebisdithiocarbamates are not highly toxic and degrade rapidly in the presence of moisture and oxygen, forming different compounds. One of these is the polar ethylenethiourea, which is relatively stable. Thus, this compound appears to be a potential contaminant for groundwater. Batch experiments were carried out under biotic as well as abiotic conditions to study the degradation dependence of concentration. temperature and organic matter. The decomposition of ethylenethiourea under abiotic conditions was found to be less than 5% of the degradation under biotic conditions. Further, ethylenethiourea showed to be stable over a period of 150 days at 20 degrees C in tap water as well as in batch with soil sterilized with NaN3. The degradation of ethylenethiourea depends on the concentration in the water implying first order reaction kinetics. The microbial degradation of ethylenethiourea is highly temperature dependent with aerobic Q10 between 2.9 and 4.2, and an anaerobic between 2.1 and 2.5. A minor increase in degradation rates was observed by application of nitrate and manure to the batches. The experiments show extremely complete degradation of ethylenethiourea in the presence of microbial nitrate reduction with pyrite which occurs in deeper parts of the aquifers.
Environmental and biological monitoring of exposure to ethylenebisdithiocarbamate fungicides and ethylenethiourea
Exposure of workers to ethylenebisdithiocarbamates (EBDCs; maneb or mancozeb) in 29 potato farms was evaluated during the control of potato late blight. Concentrations of EBDCs and ethylenethiourea (ETU), an impurity and degradation product in EBDC formulations, in ambient air were evaluated during pesticide application. Biological monitoring of exposure to EBDCs was carried out by measuring the concentrations of ETU, a metabolite of EBDCs, in urine for 22 days after the end of the exposure. The estimated inhaled doses of ETU and EBDCs during the average four hour application period were 0.07 and 1.8 micrograms/kg, respectively. Only 1-10% of ETU on the clothes reached the skin. The creatinine corrected concentrations of ETU in urine were 0.1-2.5 micrograms/mmol creatinine 24 hours after exposure ended. The estimated half life for eliminating ETU through the kidneys was close to 100 hours. These results indicate that the measurement of ETU in urine is suitable for biological monitoring of exposure to EBDCs.
Ethylenethiourea in Air and in Urine as an Indicator of Exposure to Ethylenebisdithiocarbamate Fungicides
Ethylenethiourea (ETU) is a ubiquitous impurity of the ethylenebisdithiocarbamate (EBDC) fungicides widely used in agriculture and forestry. In the present study, ETU was used as a measure of the exposure to EBDC on potato farms and in pine nurseries during the application of EBDC fungicides and the weeding of the sprayed vegetation. Biological and hygienic monitoring was carried out through the analysis of ETU in the breathing zone and the urine of exposed workers. Even if the concentrations of ETU in the ambient air of pine nurseries exceeded those of potato farms, the concentrations of ETU in the urine of potato farmers exceeded those of pine nursery workers. This result may have been due better protective equipment in the pine nurseries. The excretion rate was 6—10 ng/h during the first 60 h after the cessation of exposure, and it diminished thereafter to 0.2 ng/h over a 22-d observation period.
Rack1‐mediated ferroptosis affects hindgut development in rats with anorectal malformations: Spatial transcriptome insights
Anorectal malformation (ARM), a common congenital anomaly of the digestive tract, is a result of insufficient elongation of the urorectal septum. The cytoplasmic protein Receptor of Activated C‐Kinase 1 (Rack1) is involved in embryonic neural development; however, its role in embryonic digestive tract development and ARM formation is unexplored. Our study explored the hindgut development and cell death mechanisms in ARM‐affected rats using spatial transcriptome analysis. We induced ARM in rats by administering ethylenethiourea via gavage on gestational day (GD) 10. On GDs 14–16, embryos from both normal and ARM groups underwent spatial transcriptome sequencing, which identified key genes and signalling pathways. Rack1 exhibited significant interactions among differentially expressed genes on GDs 15 and 16. Reduced Rack1 expression in the ARM‐affected hindgut, verified by Rack1 silencing in intestinal epithelial cells, led to increased P38 phosphorylation and activation of the MAPK signalling pathway. The suppression of this pathway downregulated Nqo1 and Gpx4 expression, resulting in elevated intracellular levels of ferrous ions, reactive oxygen species (ROS) and lipid peroxides. Downregulation of Gpx4 expression in the ARM hindgut, coupled with Rack1 co‐localisation and consistent mitochondrial morphology, indicated ferroptosis. In summary, Rack1, acting as a hub gene, modulates ferrous ions, lipid peroxides, and ROS via the P38‐MAPK/Nqo1/Gpx4 axis. This modulation induces ferroptosis in intestinal epithelial cells, potentially influencing hindgut development during ARM onset. Spatial transcriptome sequencing of normal and anorectal malformation (ARM) rat embryos revealed that Rack1, as a hub gene, was decreased in the ARM hindgut on GD15 and GD16, and increased intracellular ferrous ions, reactive oxygen species, and lipid peroxides through the P38/Nqo1/Gpx4 axis, inducing ferroptosis in intestinal epithelial cells, which may affect the hindgut development in rat with ARM.
Microarray analysis of miRNAs during hindgut development in rat embryos with ethylenethiourea-induced anorectal malformations
Anorectal malformations (ARMs) are one of the most common congenital malformations of the digestive tract; however, the pathogenesis of this disease remains to be fully elucidated. MicroRNAs (miRNAs) are important in gastrointestinal development and may be involved in the pathogenesis of ARMs. The present study aimed to profile miRNAs and examine their potential functions in rats with ethylenethiourea (ETU)-induced ARMs. Pregnant Wistar rats (n=36) were divided randomly into ETU-treated and control groups. The rats in the ETU-treated group were gavage-fed 1% ETU (125 mg/kg) on gestational day 10 (GD10), whereas the control group rats received a corresponding dose of saline. Embryos were harvested by cesarean section on GD14, GD15 and GD16. Hindgut tissue was isolated from the fetuses for RNA extraction and microarray analysis, followed by bioinformatics analysis and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) validation. Overall, 38 miRNAs were differentially expressed (all upregulated) on GD14, 49 (32 upregulated and 17 downregulated) on GD15, and 42 (all upregulated) on GD16 in the ARM group compared with the normal group. The top 18 miRNAs with |log2(fold change)| >4.25 were selected for further bioinformatics analysis. Among these miRNAs, five were differentially expressed at two time-points and were involved in ARM-associated signaling pathways. The RT-qPCR analysis revealed that three miRNA (miR), miR-125b-2-3p, miR-92a-2-5p and miR-99a-5p, were significantly differentially expressed in rats with ARMs compared with the normal group. In conclusion, the results suggested that the differential expression of miR-125b-2-3p, miR-92a-2-5p and miR-99a-5p during key time-points of anorectal formation in rats may have functions in the pathogenesis of ARM.
Abnormal expression of TBX4 during anorectal development in rat embryos with ethylenethiourea-induced anorectal malformations
Background To assess the expression of T-box transcription factor 4 (TBX4) during the anorectal development in normal and ethylenethiourea (ETU)-induced anorectal malformations (ARM) rat embryos. Methods Anorectal malformations was induced by ETU on the 10th gestational day (E10) in rat embryos. Spatio-temporal expression of TBX4 was evaluated in normal (n = 490) and ETU-induced ARM rat embryos (n = 455) from E13 to E16 by immunohistochemical staining, Western blot analysis and real-time RT-PCR. Results In the normal embryos, immunohistochemical staining revealed that TBX4 expression was detected in the epithelium of hindgut and urorectal septum (URS) on E13. TBX4-immunopositive cells were increased significantly in the epithelium of hindgut and URS, the future anal orifice part of cloacal membrane on E14. On E15, abundant stained cells were observed in the rectum, URS and dorsal cloacal membrane and the expression of positive cells reached its peak. On E16, only sporadic positive cells were distributed in the epithelium of the distal rectum. In the ARM embryos, the hindgut/rectum, URS and dorsal cloacal membrane were faint for TBX4 immunohistochemical staining. In the normal group, TBX4 protein and mRNA expression showed time-dependent changes in the hindgut/rectum from E13 to E16 on Western blot and real-time RT-PCR. On E13 and E15, the expression level of TBX4 mRNA in the ARM group was significantly lower than that in the normal group ( P  < 0.05). On E15, the expression level of TBX4 protein in the ARM group was significantly lower than that in the normal group ( P  < 0.05). Conclusions The expression of TBX4 was downregulated in ETU-induced ARM embryos, which may play important roles in the pathogenesis of anorectal development.