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1.
Sci Total Environ ; 933: 173162, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38735311

RESUMEN

Traditional rice-fish symbiosis systems efficiently use soil and water resources but the adverse effects of prolonged flooding on the stability of rice growth can be mitigated. The feasibility and efficacy of injecting micro-nano bubbles (MNBs) in rice-crayfish co-cultures was investigated in a 22-hectare field experiment conducted over five months. This injection significantly enhanced the growth of both rice and crayfish, and increased total nitrogen and phosphorus levels in the soil, thereby augmenting fertility. Analysis of dissolved oxygen (DO), water temperature and gene expression (rice and crayfish) clarified that micro-nano bubbles (MNBs) foster an optimal environment for rice root respiration, whereas rice establishes an optimal temperature for crayfish, thereby enhancing their activity and growth. Comparative analyses of gene expression profiles and metabolic pathway enrichment revealed that the injection of MNBs diversifies soil microbial communities and intensifies biological processes, such as plant hormone signal transduction. This was in marked contrast to the situation in our controls, rice monoculture (R) and micro-nano bubbles rice monoculture (MNB-R). The combination of rice-fish symbiosis with MNBs led to a 26.8 % increase in rice production and to an estimated 35 % improvement in economic efficiency. Overall, this research introduces an innovative and environmentally sustainable method to boost rice yields, thereby enhancing food security and providing additional income for farmers.


Asunto(s)
Astacoidea , Oryza , Animales , Astacoidea/fisiología , Técnicas de Cocultivo , Agricultura/métodos , Fósforo , Simbiosis , Nitrógeno , Suelo/química
2.
Water Res ; 253: 121316, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38377926

RESUMEN

Non-thermal plasma emerges as a promising technology for per- and polyfluoroalkyl substances (PFAS) decomposition due to its notable efficacy and environmentally friendly characteristics. In this study, we demonstrated the efficacy of a falling film dielectric barrier discharge (DBD) system for the removal of 10 PFAS, including perfluoroalkyl carboxylic acids (PFCAs), perfluoroalkyl sulfonic acids (PFSAs) and hexafluoropropylene oxide (HFPO) oligomer acids. Results showed that compounds with fluoroalkyl chain length>4 were effectively decomposed within 100 min, with long-chain PFAS demonstrating more pronounced removal performance than their short-chain analogues. The superior removal but low defluorination observed in HFPO oligomer acids could be ascribed to their ether-based structural features. The integration of experimental results with density functional theory (DFT) calculations revealed that the synergistic effects of various reactive species are pivotal to their efficient decomposition, with electrons, OH•, and NO2• playing essential roles. In contrast, the degradation of PFSAs was more dependent on electron attack than that of PFCAs and HFPO oligomer acids. Significantly, the most crucial degradation pathway for HFPO oligomer acids was the cleavage of ether CO, whether through radical or electron attack. Furthermore, the demonstrated effective removal in various water matrices showed the potential of the plasma system for removing PFAS in complex aquatic environments. This study provided mechanistic insights into PFAS degradation behavior in plasma processes, and it underscored the vital influence of molecular structures on degradability, thereby contributing to the further development and regulation of plasma-based technologies for treating PFAS in water.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Agua , Fluorocarburos/análisis , Contaminantes Químicos del Agua/análisis , Ácidos Carboxílicos , Ácidos Sulfónicos , Éteres
3.
Environ Sci Pollut Res Int ; 30(36): 86478-86483, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37432574

RESUMEN

After the departure of industrial facilities, reuse of the land in developed cities in China is problematic, due to the land contamination issues. The rapid remediation of sites with complex contamination is crucial and urgently needed. Herein, the case of on-site remediation of arsenic (As) in soil, as well as benzo(a)pyrene, total petroleum hydrocarbons, and As in groundwater was reported. For contaminated soil, the oxidant and deactivator (consisting of 20% sodium persulfate, 40% ferrous sulfate (FeSO4), and 40% portland cement) were applied to oxidize and immobilize As. As a result, the total amount and lixivium concentration of As were constrained under 20 mg/kg and 0.01 mg/L, respectively. Meanwhile, for contaminated groundwater, As and organic contaminants were treated by FeSO4/ozone and FeSO4/hydrogen peroxide with mass ratios of 1:5 and 1:8, respectively. The continuous monitoring of contaminants in 22 monitoring wells shown that all contaminants in groundwater were treated to meet the standards. In addition, the risk of secondary pollution and operation cost was effectively reduced by proper disposal and resourceful utilization. The findings indicated that the method of oxidation and precipitation/stabilization is technically, environmentally, and economically feasible for the remediation of contaminated sites with similar complex pollutants.


Asunto(s)
Arsénico , Restauración y Remediación Ambiental , Agua Subterránea , Contaminantes del Suelo , Contaminantes Químicos del Agua , Suelo , Hidrocarburos , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis
4.
Artículo en Inglés | MEDLINE | ID: mdl-37048013

RESUMEN

In the 1990s, the Institute of Electrical and Electronics Engineers (IEEE) restricted its risk assessment for human exposure to radiofrequency radiation (RFR) in seven ways: (1) Inappropriate focus on heat, ignoring sub-thermal effects. (2) Reliance on exposure experiments performed over very short times. (3) Overlooking time/amplitude characteristics of RFR signals. (4) Ignoring carcinogenicity, hypersensitivity, and other health conditions connected with RFR. (5) Measuring cellphone Specific Absorption Rates (SAR) at arbitrary distances from the head. (6) Averaging SAR doses at volumetric/mass scales irrelevant to health. (7) Using unrealistic simulations for cell phone SAR estimations. Low-cost software and hardware modifications are proposed here for cellular phone RFR exposure mitigation: (1) inhibiting RFR emissions in contact with the body, (2) use of antenna patterns reducing the Percent of Power absorbed in the Head (PPHead) and body and increasing the Percent of Power Radiated for communications (PPR), and (3) automated protocol-based reductions of the number of RFR emissions, their duration, or integrated dose. These inexpensive measures do not fundamentally alter cell phone functions or communications quality. A health threat is scientifically documented at many levels and acknowledged by industries. Yet mitigation of RFR exposures to users does not appear as a priority with most cell phone manufacturers.


Asunto(s)
Teléfono Celular , Exposición a la Radiación , Humanos , Ondas de Radio/efectos adversos , Comunicación
5.
Environ Sci Technol ; 55(23): 16067-16077, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34751567

RESUMEN

Efficient destruction of perfluoroalkyl compounds in contaminated waters remains a challenge because of highly stable C-F bonds. In this study, mineralization of perfluorooctanoic acid (PFOA) with high concentration (∼30 mg/L) was realized in a needle-plate pulsed discharge reactor integrated with a water jet (NPDW) to which microbubbles (MBs) with different carrier gases (air, N2, and Ar) were introduced to enhance interfacial reactions. MBs effectively enrich dispersed PFOA from a bulk solution to a liquid surface to allow enhancing contact with reactive species and also expanding the plasma discharge area and channels. The PFOA removal efficiency in air and Ar discharge reached 81.5 and 95.3% in 2 h, respectively, with a defluorination ratio of no less than 50%. Energy requirements (EE/O) ranged from 216.49 to 331.95 kWh/m3. Aside from fluoride, PFOA was degraded to a range of short-chain perfluoroalkyl acids and, to a minor extent, at least 20 other fluorinated transformation products. PFOA degradation mechanisms were proposed, including decarboxylation, hydroxylation, hydrogenation reduction, and defluorination reactions. Real water matrices (groundwater, tap water, wastewater effluent, and surface water) showed moderate impact on treatment outcomes, demonstrating the robustness of the treatment process. The study demonstrated an environmentally friendly nonthermal plasma technology for effective PFOA degradation.


Asunto(s)
Fluorocarburos , Agua Subterránea , Contaminantes Químicos del Agua , Caprilatos , Microburbujas
6.
Sci Total Environ ; 790: 147990, 2021 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34380243

RESUMEN

The plasticizer di(2-ethylhexyl) phthalate (DEHP) and its hydrolysate mono(2-ethylhexyl) phthalate (MEHP) are major toxicants from plastics, but their association with hormone-dependent cancers has been controversial. We treated the human ovarian cancer cell lines SKOV3 and A2780 with low concentrations of DEHP/MEHP, and found that although no significant effect on cell proliferation was observed, ovarian cancer cell migration, invasion, and epithelial-mesenchymal transition (EMT) were promoted by submicromolar MEHP but not DEHP. Next, ovarian cancer patient data from The Cancer Genome Atlas (TCGA) were obtained and subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) supported enrichment and Kaplan-Meier survival analyses, which identified PI3K/Akt pathway as a pivotal signaling pathway in ovarian cancer. We found that 500 nM MEHP treatment significantly increased PIK3CA expression, which could be reversed by the knockdown of peroxisome proliferator-activated receptor alpha (PPARα). Silencing PIK3CA significantly suppressed the MEHP-induced migration, invasion and EMT. In addition, we validated that MEHP treatment promoted phosphorylation of Akt and degradation of IκB-α, thereby activating NF-κB and enhancing NF-κB nuclear translocation. In nude mice, MEHP exposure significantly promoted the metastasis of ovarian cancer xenografts, which could be suppressed by the treatment of PPARα inhibitor GW6471. Our findings showed that low-dose MEHP promoted ovarian cancer progression through activating PI3K/Akt/NF-κB pathway, in a PPARα-dependent manner.


Asunto(s)
Dietilhexil Ftalato , Neoplasias Ováricas , Animales , Línea Celular Tumoral , Dietilhexil Ftalato/análogos & derivados , Dietilhexil Ftalato/toxicidad , Femenino , Humanos , Ratones , Ratones Desnudos , FN-kappa B , Neoplasias Ováricas/inducido químicamente , PPAR alfa/genética , Fosfatidilinositol 3-Quinasas , Ácidos Ftálicos , Proteínas Proto-Oncogénicas c-akt
7.
Sci Total Environ ; 787: 147536, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-33992942

RESUMEN

The applications of photocatalytic pollutant degradation have remained limited due to the low efficiency of solar energy utilization. In this study, a photothermal catalyst consisting of reduced graphene oxide @ black TiO2 (RGO@BT) nanofluid with effective full-spectrum (from ultraviolet to infrared light) absorption was synthesized by a typical two-step method of high temperature calcination and hydrothermal method. Moreover, the photothermal catalytic performance of the RGO@BT nanofluid on tetracycline was verified. Compared with individual processes (i.e, photocatalysis and thermocatalysis), the photothermal catalytic process significantly enhanced tetracycline degradation under simulated global standard spectrum sunlight (AM 1.5G, 1000 W m-2). The maximum photothermal conversion efficiency reached 91.8%, which resulted in 94.7% tetracycline degradation (40 mg L-1) after 120 min of treatment with 200 mg L-1 RGO@BT nanofluid. Holes, OH, and O2- were found to be the main active species during the photothermal catalytic process. Moreover, heat was spontaneously converted from light energy without the use of any external energy source. The elevated system temperature facilitated the tetracycline degradation based on the Arrhenius behavior. These findings provide insights into the improvement of photocatalytic efficiency in organic contaminant degradation via solar energy-efficient photothermal conversion materials.


Asunto(s)
Grafito , Catálisis , Humanos , Luz , Titanio
8.
Cell Mol Immunol ; 18(5): 1278-1289, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32523112

RESUMEN

Ticagrelor is the first reversibly binding oral P2Y12 receptor antagonist to inhibit platelet activation and has been approved by the Food and Drug Administration for the treatment of coronary artery disease. At present, the other pharmacological functions of ticagrelor remain poorly understood. The NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome plays a critical role in the innate immune system, but its excessive activation also contributes to the pathogenesis of complex diseases. In this study, we systematically examined the effects of ticagrelor on the NLRP3 inflammasome and found that ticagrelor inhibits NLRP3 inflammasome activation in macrophages independent of its classic inhibitory effect on the P2Y12 signaling pathway. Further mechanistic studies demonstrate that ticagrelor attenuates the oligomerization of apoptosis-associated speck-like protein containing a CARD (ASC) by blocking chloride efflux, an effect achieved through the degradation of chloride intracellular channel proteins (CLICs) and blockade of the translocation of CLICs to the plasma membrane. Moreover, experiments on lipopolysaccharide-induced sepsis and alum-induced peritonitis in mice confirmed that ticagrelor mitigates the severity of systemic inflammation independent of P2Y12 receptor antagonism. Importantly, oral administration of ticagrelor rapidly and strongly inhibited NLRP3 inflammasome activation in peripheral blood mononuclear cells from patients with acute coronary syndrome. Overall, our study reveals a novel pharmacological function of ticagrelor in addition to its classic antiplatelet properties, which suggests that ticagrelor may serve as a potential therapeutic agent for use in NLRP3-associated diseases.


Asunto(s)
Inflamasomas/metabolismo , Inflamación/metabolismo , Inflamación/prevención & control , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Receptores Purinérgicos P2Y12/metabolismo , Transducción de Señal , Ticagrelor/farmacología , Síndrome Coronario Agudo/inmunología , Síndrome Coronario Agudo/patología , Animales , Proteínas Adaptadoras de Señalización CARD/metabolismo , Cloruros/metabolismo , Modelos Animales de Enfermedad , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Modelos Biológicos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Multimerización de Proteína
9.
J Hazard Mater ; 403: 124087, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33265066

RESUMEN

Persulfate (PS) activated by dielectric barrier discharge (DBD) integrated with microbubbles (MBs) was designed to decompose atrazine (ATZ) from aqueous solutions. The degradation efficiency reached 89% at a discharge power of 85W, a PS concentration of 1mM, and a air flow rate of 30mL/min after 75min treatment. Heat caused by DBD favoured ATZ removal. Besides, the effect of PS dosage, discharge power and initial pH values on ATZ removal was evaluated. The calculated energy yield revealed that it was economical and promising to treat 1L of ATZ-wastewaters. The existence of SO42-, Cl-, CO32- and HCO3- lead to negative effects, while positive effect was observed when the presence of MBs and humic acid. The identification results of radicals and degradation intermediates suggested that multiple synergistic effects (such as heat, eaq- and H•) activated PS, and 1O2/reactive nitrogen species, •OH and SO4-• with contributions of 18%, 26%, and 29%, were main species attacking ATZ. ATZ degradation pathways including olefination, alkylic-oxidation, dealkylation, and dechlorination were proposed. An environment-friendly and a novel method for enhancing the PS-activation and ATZ-decomposition was provided, which fully utilised the electric-chemical conversion of DBD and high mass transfer efficiency of MBs.

10.
Redox Biol ; 38: 101776, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33161305

RESUMEN

Phthalate ester plasticizers are used to improve the plasticity and strength of plastics. One of the most widely used and studied, di-2-ethylhexyl phthalate (DEHP), has been labeled as an endocrine disruptor. The major and toxic metabolic derivative of DEHP, mono-2-ethylhexyl phthalate (MEHP), is capable of interfering with mitochondrial function, but its mechanism of action on mitophagy remains elusive. Here, we report that MEHP exacerbates cytotoxicity by amplifying the PINK1-Parkin-mediated mitophagy pathway. First, MEHP exacerbated mitochondrial damage induced by low-dose CCCP via increased reactive oxygen species (ROS) production, decreased mitochondrial membrane potential (MMP), and enhanced fragmentation in mitochondria. Second, co-exposure to MEHP and CCCP ("MEHP-CCCP") induced robust mitophagy. Mechanistically, MEHP-CCCP stabilized PINK1, increased the level of phosphorylated ubiquitin (pSer 65-Ub), and led to Parkin mitochondrial translocation and activation. Third, MEHP-CCCP synergistically caused more cell death, while inhibition of mitophagy, either through chemical or gene silencing, reduced cell death. Finally and importantly, co-treatment with N-acetyl cysteine (NAC) completely counteracted the effects of MEHP-CCCP, suggesting that mitochondrial ROS played a vital role in this process. Our results link mitophagy and MEHP cytotoxicity, providing an insight into the potential roles of endocrine disrupting chemicals (EDCs) in human diseases such as Parkinson's disease.


Asunto(s)
Mitocondrias , Mitofagia , Proteínas Quinasas , Ubiquitina-Proteína Ligasas , Dietilhexil Ftalato/análogos & derivados , Humanos , Ácidos Ftálicos , Proteínas Quinasas/genética , Especies Reactivas de Oxígeno , Ubiquitina-Proteína Ligasas/genética
11.
Toxicol Lett ; 323: 35-40, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31991167

RESUMEN

This article identifies adverse effects of non-ionizing non-visible radiation (hereafter called wireless radiation) reported in the premier biomedical literature. It emphasizes that most of the laboratory experiments conducted to date are not designed to identify the more severe adverse effects reflective of the real-life operating environment in which wireless radiation systems operate. Many experiments do not include pulsing and modulation of the carrier signal. The vast majority do not account for synergistic adverse effects of other toxic stimuli (such as chemical and biological) acting in concert with the wireless radiation. This article also presents evidence that the nascent 5G mobile networking technology will affect not only the skin and eyes, as commonly believed, but will have adverse systemic effects as well.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Tecnología Inalámbrica , Consenso , Humanos
12.
J Hazard Mater ; 387: 121688, 2020 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-31776082

RESUMEN

Perfluorooctanoic acid (PFOA) from contaminated soil accumulates in higher organisms, and causes health risks to humans. In this research, 71 % of the PFOA was degraded, of which 51 % was decomposed into short chain by-products, 19 % mineralized, and 1 % volatilized with 30 kV of voltage, 50 Hz of discharge frequency, 1 % of soil moisture, 300 ppm of PFOA concentration and 6.3 of soil pH using pulsed positive discharge plasma. From a series of experiments, electrons were identified as the dominant active means of PFOA degradation. The decomposition by-products were analyzed by LC-MS. The results indicated that PFOA was decomposed into small by-products including perfluoroheptanoic acid (PFHpA), perfluorohexanoic acid (PFHxA), perfluoropentanoic acid (PFPeA), perfluorobutyric acid (PFBA), pentafluoropropionic acid (PFPrA) and trifluoroacetic acid (TFA). Moreover, in plasma treated soil, the concentration of ammonia nitrogen increased from less than 10 ppm-462 ppm, and the average dry weight of lettuce was 1.6 mg higher than that in natural soil. Additionally, Planctomycetes and Nitrospirae increased after treatment, indicating that plasma technology promotes the process of nitrogen cycle. Thus, PFOA polluted soil could be remediated using this pulse corona plasma technology, and simultaneously improve the fertility of soil without chemical injections.

13.
J Agric Food Chem ; 67(39): 10813-10822, 2019 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31490069

RESUMEN

Traditional seed pretreatment methods cause secondary pollution for the application of various chemicals. This study investigated the effect of dielectric barrier discharge (DBD) cold plasma on seedling growth. Effects of plasma-activated tap water (PATW) and plasma-activated seeds (PAS) were compared for germination rates, seedling height, dry weight, and chlorophyll content. Results show that compared with controls these growth parameters were all increased by more than 50%. The yields and contributions of hydrogen peroxide, nitrate, nitrite, and ammonium were quantified. Hydrogen peroxide and nitrate have an important role in seedling growth. By etching, the seed epidermis free radicals can reduce the apparent contact angle and increase the water absorption of the seeds. In addition to the low cost of PATW and PAS compared with commercial fertilizers, DBD does not involve any chemical addition. Thus, both PATW and PAS can be an alternative for improvement of agricultural production.


Asunto(s)
Producción de Cultivos/métodos , Pisum sativum/efectos de los fármacos , Gases em Plasma/farmacología , Semillas/crecimiento & desarrollo , Compuestos de Amonio/metabolismo , Clorofila/metabolismo , Producción de Cultivos/instrumentación , Germinación/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Nitratos/metabolismo , Pisum sativum/química , Pisum sativum/crecimiento & desarrollo , Pisum sativum/metabolismo , Gases em Plasma/química , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Semillas/química , Semillas/efectos de los fármacos , Semillas/metabolismo , Agua/química
14.
Sci Total Environ ; 661: 266-275, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30677674

RESUMEN

Gasoline contaminated soil poses an environmental and human health problem, which may be partially solved by the emerging non-thermal plasma technology. In this study a pulse corona discharge (PCD) reactor was employed to degrade gasoline in soil and simultaneously to fix nitrogen in soil. The gasoline removal rates were influenced by input power, electrode gap, gas flow rate, initial gasoline concentration, soil pH, and soil moisture. This technology produced no secondary pollution. Ozone, NOx, and hydroxyl radicals, generated directly on the soil surface, were identified as the primary agents responsible for gasoline degradation. The role of the major active agents was determined by ventilating different gases during the corona discharges. In addition, the concentration of nitrate and wettability of soil was increased after the treatment. Safety and fertility of treated soil were investigated by planting lettuce. Thus, soil pollution was remediated using this non-thermal plasma treatment, while simultaneously improving soil nitrogen content and physical characteristics. This process potentially enhances soil fertility and revegetation, since this environmentally-friendly method does not involve other chemicals injections.

15.
Toxicol Res (Camb) ; 8(6): 833-841, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32055391

RESUMEN

Prometryn is a slightly to moderately toxic herbicide belonging to the triazine family of herbicides, which are widely used in agriculture to control the growth of various weeds. Although many studies have shown that triazine herbicides have carcinogenic potential in humans, the cytotoxic effects of prometryn on human cells, and the mechanisms underlying these effects, are not yet fully understood. The lung is one of the most important organs where there is accumulation of environmental pollutants. The aim of this study was to determine the cytotoxic effects of prometryn on normal lung cells using the human bronchial epithelial cell line BEAS-2B. We found that treatment with high concentrations of prometryn arrested BEAS-2B cell growth in the S phase, while at low concentrations the cell cycle was not affected. Furthermore, we observed changes in the expression levels of cyclin-dependent kinase 2 (CDK2) and cyclin A that were consistent with the induction of cell cycle arrest in BEAS-2B cells exposed to prometryn. We also observed the increased formation of intracellular reactive oxygen species (ROS) in BEAS-2B cells, suggesting that this cell line is sensitive to prometryn. Finally, prometryn induced DNA double-strand breaks in BEAS-2B cells. In conclusion, prometryn affected key molecules involved in cell cycle regulation, induced oxidative stress, and induced DNA damage in BEAS-2B cells, which may shed light on the mechanism by which prometryn promotes lung cancer development.

16.
Toxicol Lett ; 280: 232-237, 2017 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-28851584

RESUMEN

Inorganic lead is one of the most common causes of environmental metal poisonings, and its adverse effects on multiple body systems are of great concern. The brain, along with the kidneys, are critically susceptible to lead toxicity for their hosting of high affinity lead binding proteins, and very sensitive physiology. Prolonged low-lead exposure frequently remains unrecognized, causes subtle changes in these organ systems, and manifests later at an irreversible stage. With the repeated documentation of "no safe blood lead level", the pernicious effects of lead at any measurable concentration need to be emphasized. In this review, we surveyed articles on chronic low-level lead exposures with a blood lead concentrations <10µg/dL and the development of neurobehavioral or renal disorders. The negative impacts of lead on both nervous and renal systems were obvious at a blood lead concentration of 2µg/dL, with the absence of any detectable threshold. The deleterious effect of lead on two different organ systems at such low concentrations drew our attention to the various extracellular and intracellular events that might be affected by minimal concentration of body lead, especially blood lead. Is there a true common ground between low-level lead toxicity in both the nervous system and the kidney?


Asunto(s)
Intoxicación por Plomo/prevención & control , Plomo/toxicidad , Animales , Contaminación de Alimentos , Humanos , Plomo/administración & dosificación , Concentración Máxima Admisible
17.
PLoS One ; 10(5): e0127451, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25996772

RESUMEN

BACKGROUND: Little is known regarding the effects of environmental exposure of chemicals on androgenic system in the general population. We studied 5,107 subjects included in the National Health and Nutrition Examination Survey (2011-2012). METHODS: Urinary, serum, and blood levels of 15 subclasses comprising 110 individual chemicals were analyzed for their association with serum testosterone levels. The subjects were divided into high and low testosterone groups according to the median testosterone concentration (374.51 ng/dL). Odds ratios (ORs) of individual chemicals in association with testosterone were estimated using logistic regression after adjusting for age, ethnicity, cotinine, body mass index, creatinine, alcohol, and the poverty income ratio. RESULTS: Adjusted ORs for the highest versus lowest quartiles of exposure were 2.12 (95% CI: 1.07, 4.21; Ptrend = 0.044), 1.84 (95% CI: 1.02, 3.34; Ptrend = 0.018) for the association between urinary mandelic acid, and strontium quartiles with low testosterone concentrations in adult men, respectively. However, no association was observed for the remaining chemicals with testosterone. CONCLUSIONS: The National Health and Nutrition Examination Survey data suggest that elevations in urinary mandelic acid, and strontium levels are negatively related to low serum testosterone levels in adult men.


Asunto(s)
Ácidos Mandélicos/orina , Vigilancia en Salud Pública , Estroncio/orina , Testosterona/sangre , Adulto , Anciano , Exposición a Riesgos Ambientales , Contaminantes Ambientales , Etnicidad , Historia del Siglo XXI , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Oportunidad Relativa , Factores de Riesgo , Estados Unidos/epidemiología
18.
Electromagn Biol Med ; 33(4): 264-75, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23915261

RESUMEN

BACKGROUND: Biological effects of extra-low-frequency (ELF) magnetic fields (MFs) have lacked a credible mechanism of interaction between MFs and living material. OBJECTIVES: To examine the effect of ELF-MFs on cancer cells. METHODS: Five cancer cell lines were exposed to ELF-MFs within the range of 0.025-5 µT, and the cells were examined for karyotype changes after 6 d. RESULTS: All cancer cells lines lost chromosomes from MF exposure, with a mostly flat dose-response. Constant MF exposures for three weeks allow a rising return to the baseline, unperturbed karyotypes. From this point, small MF increases or decreases are again capable of inducing karyotype contractions (KCs). Our data suggest that the KCs are caused by MF interference with mitochondria's adenosine triphosphate synthase (ATPS), compensated by the action of adenosine monophosphate-activated protein kinase (AMPK). The effects of MFs are similar to those of the ATPS inhibitor, oligomycin. They are amplified by metformin, an AMPK stimulator, and attenuated by resistin, an AMPK inhibitor. Over environmental MFs, KCs of various cancer cell lines show exceptionally wide and flat dose-responses, except for those of erythroleukemia cells, which display a progressive rise from 0.025 to 0.4 µT. CONCLUSIONS: The biological effects of MFs are connected to an alteration in the structure of water that impedes the flux of protons in ATPS channels. These results may be environmentally important, in view of the central roles played in human physiology by ATPS and AMPK, particularly in their links to diabetes, cancer and longevity.


Asunto(s)
Campos Magnéticos , Neoplasias/metabolismo , Adenosina Trifosfato/metabolismo , Línea Celular Tumoral , Proliferación Celular , Cromosomas Humanos/genética , Cromosomas Humanos/metabolismo , Humanos , Neoplasias/genética , Neoplasias/patología , Oligomicinas/metabolismo , Proteínas Quinasas/metabolismo
19.
Tumour Biol ; 33(1): 195-205, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22090169

RESUMEN

The metabolism of cultured cancer cells is stimulated by 21% oxygen and generous nutrition, while real tumors grow in oxygen and nutrient-restricted environments. The effect of these contrasted conditions was studied in five hyperploid (54-69) cancer cell lines. When grown under anoxia and in the presence of antioxidant metabolic restrictors, the cell lines quickly reverted to almost normal chromosome numbers (47-49). The stepped withdrawal of oxygen over K562 showed progressive increases in proliferation rate and the acquisition of a stable, stem phenotype. In genetic studies, hyperploid cancer cells adjusted their chromosome numbers up or down to match their micro-environment through rapid mechanisms of endo-reduplication or chromosome loss. These fast reactions may explain the surprising adaptability of tumor cells to oncologic interventions. Furthermore, karyotype contraction may provide a basis for the previously observed carcinogenic influence of the administration of some antioxidants in human populations.


Asunto(s)
Inestabilidad Cromosómica , Cariotipo , Neoplasias/genética , Neoplasias/patología , Oxígeno/metabolismo , Técnicas de Cultivo de Célula , Hipoxia de la Célula , Línea Celular Tumoral , Proliferación Celular , Humanos , Cariotipificación , Neoplasias/metabolismo
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