21 results on '"Maldonado-Vega M"'
Search Results
2. Why are we a Sensitive Population to COVID-19?
- Author
-
Maldonado Vega M and Farias Serratos F
- Subjects
education.field_of_study ,Coronavirus disease 2019 (COVID-19) ,Geography, Planning and Development ,Population ,Management, Monitoring, Policy and Law ,Biology ,education ,Demography - Published
- 2020
3. Lead: intestinal absorption and bone mobilization during lactation
- Author
-
Maldonado-Vega, M., primary, Cerbón-Solorzano, J., additional, Albores-Medina, A., additional, Hernández-Luna, C., additional, and Calderón-Salinas, JV, additional
- Published
- 1996
- Full Text
- View/download PDF
4. Evolution of lead toxicity in a population of children
- Author
-
Calderón-Salinas, JV, primary, Hernandez-Luna, C., additional, Valdez-Anaya, B., additional, Maldonado-Vega, M., additional, and Lopez-Miranda, A., additional
- Published
- 1996
- Full Text
- View/download PDF
5. The effects of dietary calcium during lactation on lead in bone mobilization: implications for toxicology.
- Author
-
Maldonado Vega, M, Cerbón Solórzano, J, and Calderón Salinas, JV
- Subjects
- *
DIETARY calcium , *LACTATION , *LEAD in the body , *BONES - Abstract
Under a normal 1.0% calcium (Ca) concentration in the diet during and after chronic lead (Pb) intoxication, there was a significant increment in the concentration of Pb in the blood, kidney, liver and brain during lactation, parallel to a decrement of Pb in the bone. The increment of Pb in the brain was accompanied by an enhanced lipid oxidation (increase in conjugated dienes). During lactation, on the first 14 days, when dietary Ca was reduced to 0.05%, bone Ca concentration was decreased by 15%, bone resorption measured as acid phosphatase activity in plasma increased three times and Pb bone concentration dropped by 30%. Under a 0.05% Ca in the diet in the nonlactating rats, Ca in the bone decreases also, but there were neither increments in bone resorption nor Pb efflux from the bone. These results suggested that Pb efflux in the bone was related to bone resorption during lactation. Interestingly, when dietary Ca was enhanced to 2.5% in lactating rats, Ca concentration in the bone increased by 21%, but resorption did not decrease and Pb bone concentration decreased by 28%, enhancing toxicity. In the control Pb-exposed nonlactating rats under a 2.5% Ca in the diet, Ca concentration in the bone was increased (18%), and Pb concentration in the bone was unaltered. Since Ca metabolism changes drastically in humans during pregnancy and lactation, and it is likely that bone Pb is mobilized and transferred to the more available compartments of the maternal circulation, the increment in daily intake of Ca during lactation could enhance Pb efflux from the bone. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
6. Response surface applied to the treatment of wastewater with the coupling of DSA and photocatalysis | Superficie de respuesta aplicada al tratamiento de aguas residuales acoplando DSA y fotocatálisis
- Author
-
Eloy Isarain Chavez, Ramírez-Martínez, S., Maldonado-Vega, M., Lambert, J., Peralta-Hernández, J. M., and Morales-Ortiz, U.
7. Characterization and recovery of hexavalent chromium salts from a hazardous waste site | Caracterización y recuperación de sales de cromo hexavalente de un pasivo ambiental
- Author
-
Rangel Cordova, A. A., Eloy Isarain Chavez, and Maldonado Vega, M.
8. Bioaerosols and evaluation of air quality in two hospital centers located in Leon, Guanajuato, Mexico,Bioaerosoles y evaluación de la calidad del aire en dos centros hospitalarios ubicados en León, Guanajuato, México
- Author
-
Maldonado-Vega, M., Peña-Cabriales, J. J., Sergio de los Santos Villalobos, Castellanos-Arévalo, A. P., Camarena-Pozos, D., Arévalo-Rivas, B., Valdés-Santiago, L., Hernández-Valadez, L. J., and Peña, D. L. G.
9. Adaptive changes in redox response and decreased platelet aggregation in lead-exposed workers.
- Author
-
Hernández-García S, Flores-García M, Maldonado-Vega M, Hernández G, Meneses-Melo F, López-Vanegas NC, and Calderón-Salinas JV
- Subjects
- Humans, Blood Platelets, Reactive Oxygen Species metabolism, Oxidation-Reduction, Adenosine Diphosphate metabolism, Platelet Aggregation, Lead toxicity
- Abstract
Chronic lead exposure can generate pro-oxidative and pro-inflammatory conditions in the blood, related to high platelet activation and aggregation, altering cell functions. We studied ADP-stimulated aggregation and the oxidant/antioxidant system of platelets from chronically lead-exposed workers and non-exposed workers. Platelet aggregation was low in lead-exposed workers (62 vs. 97%), who had normal platelet counts and showed no clinical manifestations of hemostatic failure. ADP-activated platelets from lead-exposed workers failed to increase superoxide release (3.3 vs. 6.6 µmol/g protein), had low NADPH concentration (60 vs. 92 nmol/mg protein), high concentration of hydrogen peroxide (224 vs. 129 nmol/mg protein) and high plasma PGE
2 concentration (287 vs. 79 pg/mL). Altogether, those conditions, on the one hand, could account for the low platelet aggregation and, on the other, indicate an adaptive mechanism for the oxidative status of platelets and anti-aggregating molecules to prevent thrombotic problems in the pro-oxidant and pro-inflammatory environment of chronic lead exposure., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
10. Epidemiology of Breast Cancer in Mexican Women with Obesity as a Risk Factor.
- Author
-
Cejudo-Arteaga S, Guerrero-Ramos MÁ, Kuri-Exome R, Martínez-Cordero E, Farias-Serratos F, and Maldonado-Vega M
- Subjects
- Adult, Carcinoembryonic Antigen, Female, Hormones therapeutic use, Humans, Inflammation complications, Lipids therapeutic use, Middle Aged, Neoplasm Recurrence, Local, Obesity complications, Obesity epidemiology, Overweight epidemiology, Retrospective Studies, Risk Factors, Breast Neoplasms drug therapy, Breast Neoplasms epidemiology, Breast Neoplasms etiology
- Abstract
Purpose. Adipose tissue in overweight and obesity shows metabolic imbalance in the function of adipocytes and macrophages, this leads to altered regulation of hunger, lipid storage, and chronic inflammation possibly related to the development of breast cancer. Methods. The study was retrospective of 653 breast cancer patients treated at a tertiary care hospital. Histopathology, hormone receptors, grade, clinical stage, clinical biometry analysis, CEA and CA 15-3 antigens were analyzed. The analyses were performed at diagnosis and at the end of oncological treatments. Results. Mexican women studied and treated for breast cancer have an BMI of 29 from diagnosis and at the end of their cancer treatments. The average age was 52 ± 12 years, 54% in women older than 55 years. Cancer recurrence occurs in any molecular type; however, the common factor was overweight and obesity with 73% vs. 21% in normal weight patients. The most frequent tumor tissue in the population was positive hormone receptors of the luminal type (65%), HER2 (15%), and NT (15%). The analyses of macrophages/lymphocytes (M/L), CEA, and CA 15-3 antigens evaluated in women >55 and <55 years, with and without recurrence are elevated at the end of oncological treatments. Conclusions. The analysis of Mexican women with breast cancer showed a predominance of overweight and obesity at diagnosis and at the end of treatment. A relationship between obesity and cancer recurrence with a low response to treatment due to elevation in Ag CEA and CA 15-3 is suggested. The L/M ratio could be an indicator of inflammation related to adipose tissue since diagnosis.
- Published
- 2022
- Full Text
- View/download PDF
11. Role of Ape1 in Impaired DNA Repair Capacity in Battery Recycling Plant Workers Exposed to Lead.
- Author
-
Hernández-Franco P, Maldonado-Vega M, Calderón-Salinas JV, Rojas E, and Valverde M
- Subjects
- DNA Repair, Humans, Lead toxicity, Porphobilinogen Synthase, Recycling, Lead Poisoning, Occupational Exposure adverse effects, Occupational Exposure analysis
- Abstract
Exposure to lead in environmental and occupational settings continues to be a serious public health problem. At environmentally relevant doses, two mechanisms may underlie lead exposition-induced genotoxicity, disruption of the redox balance and an interference with DNA repair systems. The aim of the study was to evaluate the ability of lead exposition to induce impaired function of Ape1 and its impact on DNA repair capacity of workers chronically exposed to lead in a battery recycling plant. Our study included 53 participants, 37 lead exposed workers and 16 non-lead exposed workers. Lead intoxication was characterized by high blood lead concentration, high lipid peroxidation and low activity of delta-aminolevulinic acid dehydratase (δ-ALAD). Relevantly, we found a loss of DNA repair capacity related with down-regulation of a set of specific DNA repair genes, showing specifically, for the first time, the role of Ape1 down regulation at transcriptional and protein levels in workers exposed to lead. Additionally, using a functional assay we found an impaired function of Ape1 that correlates with high blood lead concentration and lipid peroxidation. Taken together, these data suggest that occupational exposure to lead could decrease DNA repair capacity, inhibiting the function of Ape1, as well other repair genes through the regulation of the ZF-transcription factor, promoting the genomic instability.
- Published
- 2022
- Full Text
- View/download PDF
12. Leukocyte apoptosis, TNF-α concentration and oxidative damage in lead-exposed workers.
- Author
-
López-Vanegas NC, Hernández G, Maldonado-Vega M, and Calderón-Salinas JV
- Subjects
- Adult, Case-Control Studies, Erythrocytes pathology, Female, Humans, Immunity drug effects, Lead blood, Lipid Peroxidation, Male, Middle Aged, Oxidative Stress, Porphobilinogen Synthase blood, Apoptosis drug effects, Lead Poisoning pathology, Leukocytes pathology, Occupational Exposure, Tumor Necrosis Factor-alpha blood
- Abstract
Lead intoxication can generate pro-inflammatory conditions that have been proposed to be associated with cell injuries and oxidative stress. The pro-inflammatory state can participate in the pathophysiology of this toxicity to generate immune response dysfunctions, which could condition the presence of clinical manifestations and susceptibility to infections already described in lead-exposed patients. In the present work, we study workers of a battery recycler factory (n = 24) who are chronically exposed to lead and compared them with non-lead exposed workers (n = 17). Lead-exposed workers had high lead concentrations in blood (med 69.8 vs. 1.7 μg/dL), low δ-ALAD activity (med 149 vs. 1100 nmol PBG/h/mL), high lipid peroxidation (med 0.86 vs. 0.69 nmol/mL) and high erythrocytes apoptosis (med 0.81 vs. 0.50% PS externalization) in relation to non-lead exposed workers. Also, lead-exposed workers had a high incidence of signs and symptoms related to lead intoxication and a higher frequency of infections. The higher leukocyte apoptosis (med 18.3 vs. 8.2% PS externalization) and lower basal TNF-α concentration (med 0.38 vs. 0.94 pg/mL) in lead-exposed workers imply an immune response dysfunction; however, there was no difference in the TNF-α concentration when leukocytes were stimulated with lipopolysaccharide in whole blood (med 44 vs. 70 pg/mL), suggesting that lead-exposed workers might develop adaptation mechanisms to reduce basal TNF-α release through downregulation processes proposed for this cytokine., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
13. Hepatocellular Carcinoma of Fibrolamellar Type in an Adolescent: Case Report and Literature Review.
- Author
-
Santiago-Reynoso J, Zamaripa-Martínez KS, Dorantes-Loya JM, Gaytán-Fernández GJ, Apolinar-Jiménez E, Paz-Gómez F, Farias-Serratos F, and Maldonado-Vega M
- Abstract
We present a female patient, 13 years old, with diagnosis of hepatocellular carcinoma of fibrolamellar type, which was rapidly evolving. The fibrolamellar hepatocellular carcinoma invaded more than 80% of the hepatic parenchyma without surgical possibility or liver transplantation. Measures applied corresponded to chemotherapy of 1 cycle of cisplatin 40 mg/s/5 days + vincristine 1.5 mg/m
2 /day, 5-fluorouracil, doxorubicin, and dexrazoxane. The case presented aggressive evolution of hepatocellular carcinoma, which led to acute liver failure, with hyperammonemia, sepsis, pulmonary focus plus septic shock, grade III-IV encephalopathy, portal hypertension, and ascites with intra-abdominal hypertension. Death occurred due to multiple organ failure, which involved respiratory failure type KDIGO 1 and 2, acute liver failure, severe pneumonia, pericardial effusion, AKIN 2 acute kidney injury, carcinoma, and pulmonary metastasis. This type of ailment is infrequent in children and adolescents, and the first symptoms are crucial to achieve treatment possibilities., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2019 by S. Karger AG, Basel.)- Published
- 2019
- Full Text
- View/download PDF
14. Participation of phospholipase-A 2 and sphingomyelinase in the molecular pathways to eryptosis induced by oxidative stress in lead-exposed workers.
- Author
-
Hernández G, Villanueva-Ibarra CA, Maldonado-Vega M, López-Vanegas NC, Ruiz-Cascante CE, and Calderón-Salinas JV
- Subjects
- Adult, Biomarkers blood, Case-Control Studies, Environmental Pollutants blood, Erythrocytes enzymology, Erythrocytes pathology, Humans, Lead blood, Lead Poisoning blood, Lead Poisoning enzymology, Lead Poisoning pathology, Lipid Peroxidation drug effects, Middle Aged, Porphobilinogen Synthase blood, Risk Assessment, Signal Transduction, Young Adult, Environmental Pollutants adverse effects, Eryptosis drug effects, Erythrocytes drug effects, Lead adverse effects, Lead Poisoning etiology, Occupational Exposure adverse effects, Oxidative Stress drug effects, Phospholipases A2 blood, Sphingomyelin Phosphodiesterase blood
- Abstract
The increment of eryptosis in lead-exposed workers has been associated with oxidative stress, having as the main mediator [Ca
2+ ]i . However, other molecules could participate as signals, such as PLA2 and SMase, which have been proposed to increase PGE2 and ceramides, both involved in the increment of PS externalization due to osmotic stress. To study the role of these enzymes in lead intoxication, we studied 30 lead exposed workers and 27 non-lead exposed individuals. We found, compared to non-exposed subjects, lead intoxication characterized by high blood lead concentration (median = 39.1 μg/dL), and low δ-ALAD activity (median = 348 nmol of porphobilinogen/h/mL); oxidative stress with high lipid peroxidation (median = 1.31 nmol of malondialdehyde/mL) and low TAC (median = 370 mM Trolox equivalents); a higher enzymatic activity of PLA2 (median = 518 AFU/mg) and SMase (median = 706 AFU/mg) and higher eryptosis (median = 0.92% PS externalization). Correlation and conditional probability analyses permit to associate oxidative stress and eryptosis with high PLA2 activity. However, high SMase activity was only associated with PLA2 activity. The role of these enzymes in the signal path to eryptosis induced by oxidative stress in lead-exposed workers is discussed., (Copyright © 2019 Elsevier Inc. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
15. Induced accumulation of Au, Ag and Cu in Brassica napus grown in a mine tailings with the inoculation of Aspergillus niger and the application of two chemical compounds.
- Author
-
González-Valdez E, Alarcón A, Ferrera-Cerrato R, Vega-Carrillo HR, Maldonado-Vega M, Salas-Luévano MÁ, and Argumedo-Delira R
- Subjects
- Aspergillus niger physiology, Brassica napus drug effects, Brassica napus microbiology, Plant Leaves metabolism, Plant Roots metabolism, Thiocyanates pharmacology, Thiosulfates pharmacology, Brassica napus metabolism, Copper metabolism, Gold metabolism, Mining, Silver metabolism
- Abstract
This study evaluated the ability of Brassica napus for extracting gold (Au), silver (Ag) and copper (Cu) from a mine tailings, with the inoculation of two Aspergillus niger strains, and the application of ammonium thiocyanate (NH
4 SCN) or ammonium thiosulfate [(NH4 )2 S2 O3 ]. After seven weeks of growth inoculated or non-inoculated plants were applied with 1 or 2 g kg-1 of either NH4 SCN or (NH4 )2 S2 O3 , respectively. Eight days after the application of the chemical compounds, plants were harvested for determining the total dry biomass, and the content of Au, Ag, and Cu in plant organs. Application of (NH4 )2 S2 O3 or NH4 SCN resulted in enhanced Au-accumulation in stems (447% and 507%, respectively), while either (NH4 )2 S2 O3 +Aspergillus, or NH4 SCN increased the Au-accumulation in roots (198.5% and 404%, respectively) when compared to the control. Treatments with (NH4 )2 S2 O3 or (NH4 )2 S2 O3 +Aspergillus significantly increased (P ≤ 0.001) the accumulation of Ag in leaves (677% and 1376%, respectively), while NH4 SCN + Aspergillus, and (NH4 )2 S2 O3 enhanced the accumulation in stems (7153% and 6717.5%). The Ag-accumulation in roots was stimulated by NH4 SCN+ Aspergillus, and (NH4 )2 S2 O3 + Aspergillus (132.5% and 178%, respectively), when compared to the control. The combination of NH4 SCN+Aspergillus significantly enhanced the Cu-accumulation in leaves (228%); whereas NH4 SCN+ Aspergillus, or (NH4 )2 S2 O3 + Aspergillus resulted in greater accumulation of Cu in stems (1233.5% and 1580%, respectively) than the control. Results suggest that either NH4 SCN or (NH4 )2 S2 O3 (with or without Aspergillus) improved the accumulation of Au and Ag by B. napus. Accumulation of Au and Ag in plant organs overpassed the hyperaccumulation criterion (> 1 mg kg-1 of plant biomass); whereas Cu-accumulation in stems and roots also overpassed such criterion (> 1000 mg kg-1 ) by applying either NH4 SCN or (NH4 )2 S2 O3 + A. niger., (Copyright © 2018 Elsevier Inc. All rights reserved.)- Published
- 2018
- Full Text
- View/download PDF
16. Evaluation of microbial load in oropharyngeal mucosa from tannery workers.
- Author
-
Castellanos-Arévalo DC, Castellanos-Arévalo AP, Camarena-Pozos DA, Colli-Mull JG, and Maldonado-Vega M
- Abstract
Background: Animal skin provides an ideal medium for the propagation of microorganisms and it is used like raw material in the tannery and footware industry. The aim of this study was to evaluate and identify the microbial load in oropharyngeal mucosa of tannery employees., Methods: The health risk was estimated based on the identification of microorganisms found in the oropharyngeal mucosa samples. The study was conducted in a tanners group and a control group. Samples were taken from oropharyngeal mucosa and inoculated on plates with selective medium. In the samples, bacteria were identified by 16S ribosomal DNA analysis and the yeasts through a presumptive method. In addition, the sensitivity of these microorganisms to antibiotics/antifungals was evaluated., Results: The identified bacteria belonged to the families Enterobacteriaceae, Pseudomonadaceae, Neisseriaceae, Alcaligenaceae, Moraxellaceae, and Xanthomonadaceae, of which some species are considered as pathogenic or opportunistic microorganisms; these bacteria were not present in the control group. Forty-two percent of bacteria identified in the tanners group are correlated with respiratory diseases. Yeasts were also identified, including the following species: Candida glabrata, Candida tropicalis, Candida albicans, and Candida krusei. Regarding the sensitivity test of bacteria identified in the tanners group, 90% showed sensitivity to piperacillin/tazobactam, 87% showed sensitivity to ticarcillin/clavulanic acid, 74% showed sensitivity to ampicillin/sulbactam, and 58% showed sensitivity to amoxicillin/clavulanic acid., Conclusion: Several of the bacteria and yeast identified in the oropharyngeal mucosa of tanners have been correlated with infections in humans and have already been reported as airborne microorganisms in this working environment, representing a health risk for workers.
- Published
- 2015
- Full Text
- View/download PDF
17. Enhanced Pb Absorption by Hordeum vulgare L. and Helianthus annuus L. Plants Inoculated with an Arbuscular Mycorrhizal Fungi Consortium.
- Author
-
Arias MS, Peña-Cabriales JJ, Alarcón A, and Maldonado Vega M
- Subjects
- Agricultural Inoculants growth & development, Agricultural Inoculants metabolism, Biodegradation, Environmental, Environmental Restoration and Remediation instrumentation, Glomeromycota metabolism, Helianthus chemistry, Helianthus microbiology, Hordeum chemistry, Hordeum microbiology, Lead analysis, Mycorrhizae metabolism, Environmental Restoration and Remediation methods, Glomeromycota growth & development, Helianthus metabolism, Hordeum metabolism, Lead metabolism, Mycorrhizae growth & development
- Abstract
The effect of an arbuscular mycorrhizal fungi (AMF) consortium conformed by (Glomus intraradices, Glomus albidum, Glomus diaphanum, and Glomus claroideum) on plant growth and absorption of Pb, Fe, Na, Ca, and (32)P in barley (Hordeum vulgare L.) and sunflower (Helianthus annuus L.) plants was evaluated. AMF-plants and controls were grown in a substrate amended with powdered Pb slag at proportions of 0, 10, 20, and 30% v/v equivalent to total Pb contents of 117; 5,337; 13,659, and 19,913 mg Pb kg(-1) substrate, respectively. Mycorrhizal root colonization values were 70, 94, 98, and 90%, for barley and 91, 97, 95, and 97%, for sunflower. AMF inoculum had positive repercussions on plant development of both crops. Mycorrhizal barley absorbed more Pb (40.4 mg Pb kg(-1)) shoot dry weight than non-colonized controls (26.5 mg Pb kg(-1)) when treated with a high Pb slag dosage. This increase was higher in roots than shoots (650.0 and 511.5 mg Pb kg(-1) root dry weight, respectively). A similar pattern was found in sunflower. Plants with AMF absorbed equal or lower amounts of Fe, Na and Ca than controls. H. vulgare absorbed more total P (1.0%) than H. annuus (0.9%). The arbuscular mycorrizal consortium enhanced Pb extraction by plants.
- Published
- 2015
- Full Text
- View/download PDF
18. Eryptosis in lead-exposed workers.
- Author
-
Aguilar-Dorado IC, Hernández G, Quintanar-Escorza MA, Maldonado-Vega M, Rosas-Flores M, and Calderón-Salinas JV
- Subjects
- Adenosine Triphosphate blood, Adult, Biomarkers blood, Calcium blood, Calpain blood, Case-Control Studies, Erythrocytes, Abnormal metabolism, Erythrocytes, Abnormal pathology, Glutathione blood, Humans, Lead Poisoning blood, Lead Poisoning diagnosis, Male, Middle Aged, Occupational Diseases blood, Occupational Diseases diagnosis, Occupational Health, Oxidative Stress drug effects, Phosphatidylserines blood, Porphobilinogen Synthase blood, Recycling, Risk Assessment, Risk Factors, Thiobarbituric Acid Reactive Substances analysis, Young Adult, Electric Power Supplies adverse effects, Erythrocytes, Abnormal drug effects, Lead adverse effects, Lead Poisoning etiology, Occupational Diseases chemically induced, Occupational Exposure adverse effects
- Abstract
Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8μg/dl) and non-exposed workers (4.2μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca(2+)]i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (<0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca(2+)], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
19. Effect of vitamin E and C supplementation on oxidative damage and total antioxidant capacity in lead-exposed workers.
- Author
-
Rendón-Ramírez AL, Maldonado-Vega M, Quintanar-Escorza MA, Hernández G, Arévalo-Rivas BI, Zentella-Dehesa A, and Calderón-Salinas JV
- Subjects
- Adult, Air Pollutants, Occupational blood, Antioxidants pharmacokinetics, Ascorbic Acid blood, Ascorbic Acid pharmacokinetics, Catalase blood, Dietary Supplements, Glutathione Peroxidase blood, Glutathione Reductase blood, Humans, Lead blood, Lipid Peroxidation drug effects, Male, Occupational Exposure adverse effects, Occupational Exposure analysis, Oxidative Stress drug effects, Porphobilinogen Synthase blood, Superoxide Dismutase blood, Vitamin E blood, Vitamin E pharmacokinetics, Air Pollutants, Occupational toxicity, Antioxidants pharmacology, Ascorbic Acid pharmacology, Lead toxicity, Vitamin E pharmacology
- Abstract
The molecular response of the antioxidant system and the effects of antioxidant supplementation against oxidative insult in lead-exposed workers has not been sufficiently studied. In this work, antioxidants (vitamin E 400 IU+vitamin C 1g/daily) were supplemented for one year to 15 workers exposed to lead (73 μg of lead/dl of blood) and the results were compared with those on 19 non-lead exposed workers (6.7 μg of lead/dl). Lead intoxication was accompanied by a high oxidative damage and an increment in the erythrocyte antioxidant response due to increased activity of catalase and superoxide dismutase. Antioxidant supplementations decreased significantly the oxidative damage as well as the total antioxidant capacity induced by lead intoxication with reduction of the antioxidant enzyme activities. We conclude that antioxidant supplementation is effective in reducing oxidative damage and induces modifications in the physiopathological status of the antioxidant response in lead-exposed workers., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
20. Isolation and characterization of hexavalent chromium-reducing rhizospheric bacteria from a wetland.
- Author
-
Mauricio Gutiérrez A, Peña Cabriales JJ, and Maldonado Vega M
- Subjects
- Adaptation, Physiological drug effects, Bacteria genetics, Bacteria growth & development, Biodegradation, Environmental drug effects, Chromium toxicity, Culture Media pharmacology, Hydrogen-Ion Concentration drug effects, Industrial Waste analysis, Oxidation-Reduction drug effects, Phylogeny, Plant Roots drug effects, Plant Roots metabolism, Salinity, Sodium Chloride pharmacology, Waste Disposal, Fluid, Bacteria isolation & purification, Bacteria metabolism, Chromium isolation & purification, Chromium metabolism, Cyperaceae microbiology, Plant Roots microbiology, Wetlands
- Abstract
Scirpus americanus Pers. occurs naturally in "San Germán," a pond that serves as a receptor of industrial wastewater in Guanajuato, México. This plant accumulates metals mainly in the root: concentrations (mg/kg) of Cr, As, Cd and Se were 970, 49, 41, and 85 respectively. Analysis of rhizosphere samples indicated bacterial population of 10(8) cfu g(-1) in media with 0.2 mM Cr(VI) and 10 mM sodium gluconate. Thirteen isolates were obtained and phylogenetic analyses (16S rRNA) indicated they corresponded to genera of Agrobacterium, Arthrobacter, Microbacterium, Curtobacterium, Rhodococcus, Xanthomonas and Pseudomonas. Cr(VI) reduction was evaluated using the diphenyl carbazide method. The isolates accomplished 5-40% (20 microM) of reduction in assays of resting cell and tolerated 0.5-5.0 mM Cr(VI). Eight strains used nitrate and thirteen used iron and chromium as electron acceptors to grow under anaerobic conditions. Cr(VI) reduction by five strains occurred at pH values (7-9) and NaCl concentrations (0.5-1.0 M) in basal medium. A mixed culture of strains (S17 and S28) reached a chromium removal of 100% at 0.2 mM Cr(VI) initial concentration. Aerobically, this consortium was capable of 93.8% Cr(VI) reduction of 81 microg L(-1) Cr(VI) of the industrial effluent, indicating their possible use in environmental cleanup.
- Published
- 2010
- Full Text
- View/download PDF
21. Identification and characterization of sulfur-oxidizing bacteria in an artificial wetland that treats wastewater from a tannery.
- Author
-
Pacheco Aguilar JR, Peña Cabriales JJ, and Maldonado Vega M
- Subjects
- Bacteria genetics, Bacteria metabolism, Biodegradation, Environmental, Industrial Waste, Oxidation-Reduction, Phylogeny, Water Pollutants, Chemical metabolism, Bacteria classification, Soil Microbiology, Sulfur metabolism, Tanning, Waste Disposal, Fluid methods, Wetlands
- Abstract
Wastewater from tanneries contains high concentrations of organic matter, chromium, nitrogen, and sulfur compounds. In this study, an artificial wetland is is used as the tertiary treatment in a tannery in León Gto., México. It consists of three subplots with an area of about 450 m2. Two subplots were planted with Typha sp. and the third with Scirpus americanus. Geochemical analyses along the flowpath of the wetland show that contaminants were effectively attenuated. The most probable number technique was used to determine rhizospheric microbial populations involved in the sulfur cycle and suggested that there were 104-10(6) cells g(-1) sediment of sulfate-reducing bacteria and 10(2)-10(5) of sulfur-oxidizing bacteria (SOB). Representatives of SOB were isolated on media containing thiosulfate. Phylogenetic analysis of 16S rRNA of SOB isolates shows that they belong to the genera Acinetobacter, Alcaligenes, Ochrobactrum, and Pseudomonas. Most of the isolates are organotrophic and can oxidize reduced sulfur compounds such as elemental sulfur or thiosulfate, accumulating thiosulfate, or tetrathionate during growth. All isolates can use reduced-sulfur compounds as their sole sulfur source and some can use nitrate as an electron acceptor to grow anaerobically. Our results illustrate the relevance of SOB in the functioning of the wetland constructed for tannery wastewater remediation.
- Published
- 2008
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.