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1.
Phys Chem Chem Phys ; 26(13): 10310-10322, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38498351

RESUMEN

Pyocyanin is an important virulence factor in the resistance of Pseudomonas aeruginosa to antibiotics. Pyocyanin is a planar three ring aromatic molecule that occurs as zwitterionic (PYO) or protonated species (PYOH+). Our earlier studies have shown that montmorillonite, through adsorption and transformation, can inactivate both PYO and PYOH+ in the interlayer space. The objective of this study was to elucidate the interaction mechanisms between montmorillonite and the adsorbed pyocyanin and to characterize the structure of the pyocyanin-montmorillonite complex via molecular dynamics (MD) simulations. The MD simulations were performed for the complexes of hydrated Na-montmorillonite (HM) with (i) neutral pyocyanin (HMP) and (ii) protonated pyocyanin (HMPH); and dehydrated Na-montmorillonite (DM) with (iii) neutral pyocyanin (DMP) and (iv) protonated pyocyanin (DMPH). The simulations indicated that in dry conditions, both PYO and PYOH+ were well-ordered in the midplane of the interlayer of montmorillonite, with the three aromatic rings almost parallel to the basal surface and sandwiched in-between basal surface-adsorbed Na+ planes. In humid conditions, the pyocyanin and Na+ were solvated in the interlayer space and the pyocyanin was less ordered compared to dehydrated models. Ion-dipole interaction (Na-O) was the dominant interaction for the dehydrated complexes DMPH and DMP but the interaction was stronger in the latter. The Na-O ion-dipole interaction remained the dominant interaction in hydrated HMP while in HMPH, water outcompeted PYOH+ for Na+ resulting in water-Na interaction being the dominant interaction. These results revealed the arrangement of the two species of pyocyanin in the interlayer spaces of montmorillonite and the mechanism of interaction between the pyocyanin and montmorillonite.

2.
Cancer Lett ; 579: 216465, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-38084702

RESUMEN

Lung cancer is a highly heterogeneous malignancy, and despite the rapid development of chemotherapy and radiotherapy, acquired drug resistance and tumor progression still occur. Thus, it is urgent to identify novel therapeutic targets. Our research aims to screen novel biomarkers associated with the prognosis of lung carcinoma patients and explore the potential regulatory mechanisms. We obtained RNA sequencing (RNA-seq) data of lung cancer patients from public databases. Clinical signature analysis, weighted gene coexpression network analysis (WGCNA) and the random forest algorithm showed that C1q/tumor necrosis factor-related protein-6 (CTRP6) is a core gene related to lung cancer prognosis, and it was determined to promote tumor proliferation and metastasis both in vivo and in vitro. Mechanistically, silencing CTRP6 was determined to promote xCT/GPX4-involved ferroptosis through functional assays related to lipid peroxidation, Fe2+ concentration and mitochondrial ultrastructure. By performing interactive proteomics analyses in lung tumor cells, we identified the interaction between CTRP6 and suppressor of cytokine signaling 2 (SOCS2) leading to SOCS2 ubiquitination degradation, subsequently enhancing the downstream xCT/GPX4 signaling pathway. Moreover, significant correlations between CTRP6-mediated SOCS2 and ferroptosis were revealed in mouse models and clinical specimens of lung cancer. As inducing ferroptosis has been gradually regarded as an alternative strategy to treat tumors, targeting CTRP6-mediated ferroptosis could be a potential strategy for lung cancer therapy.


Asunto(s)
Ferroptosis , Neoplasias Pulmonares , Animales , Humanos , Ratones , Adipoquinas/metabolismo , Ferroptosis/genética , Pulmón/metabolismo , Neoplasias Pulmonares/genética , Pronóstico , Transducción de Señal , Proteínas Supresoras de la Señalización de Citocinas/metabolismo
3.
Front Oncol ; 13: 1238332, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37849806

RESUMEN

Background: Although many CTC isolation and detection methods can provide information on cancer cell counts, downstream gene and protein analysis remain incomplete. Therefore, it is crucial to develop a technology that can provide comprehensive information on both the number and profile of CTC. Methods: In this study, we developed a novel microfluidics-based CTC separation and enrichment platform that provided detailed information about CTC. Results: This platform exhibits exceptional functionality, achieving high rates of CTC recovery (87.1%) and purification (∼4 log depletion of WBCs), as well as accurate detection (95.10%), providing intact and viable CTCs for downstream analysis. This platform enables successful separation and enrichment of CTCs from a 4 mL whole-blood sample within 15 minutes. Additionally, CTC subtypes, selected protein expression levels on the CTC surface, and target mutations in selected genes can be directly analyzed for clinical utility using immunofluorescence and real-time polymerase chain reaction, and the detected PD-L1 expression in CTCs is consistent with immunohistochemical assay results. Conclusion: The microfluidic-based CTC enrichment platform and downstream molecular analysis together provide a possible alternative to tissue biopsy for precision cancer management, especially for patients whose tissue biopsies are unavailable.

4.
Front Oncol ; 12: 1028467, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36479066

RESUMEN

Background: With its growing popularity and potential outcome, preoperative three-dimensional reconstruction of chest computed tomography (CT) has been widely used in video-assisted thoracic surgery (VATS) segmentectomy for treating non-small cell lung cancer (NSCLC). This study aimed to summarize the experience of anatomical variation analysis of left upper pulmonary blood vessels and bronchi based on the three-dimensional reconstruction of chest CT. Materials and methods: A total of 103 patients with early-stage NSCLC were chosen to undergo VATS segmentectomy based on preoperative three-dimensional reconstruction of chest CT in our institute from September 2019 to July 2022. Data such as clinical characteristics and variations in blood vessels and bronchi were reviewed in this study. Results: The branches of the left lingular pulmonary artery may mutate into the LS1 + 2 + 3. A1 + 2 has four subtypes. The distribution of variation is relatively balanced, and the most common variation is type I (35/103, 33.9%). Most lingular arteries originate from the oblique cleft side of the lingular bronchus (79/103,76.7%). Most V(1 + 2)c* are small developments (70/103, 68.0%). The venous return of the proper segment mainly depends on V(1 + 2)b + c. The variation in the left upper lobe bronchus is complex. The most common variant is the bifurcation type (type A to G, 92/103, 89.3%) and bifurcation type A (62/103, 60.2%). The posterior apical segment artery of the left upper lobe is not accompanied by its bronchus. Conclusions: The variation types of blood vessels and bronchus in the upper lobe of the left lung are complex. Preoperative CT-based three-dimensional reconstruction of pulmonary arteries, veins, and bronchi is of great significance. It can help understand the variations, accurately locate lesions before the surgery, and effectively plan surgeries.

5.
Biomed Res Int ; 2022: 6175053, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35620225

RESUMEN

The vital regulation of abnormally expressed lncRNAs in human cancers has been identified. This study is aimed at illustrating the role of LINC01426 in influencing malignant behaviors of lung adenocarcinoma (LUAD) and the possible mechanism. Differential expressions of LINC01426 in a downloaded profile containing LUAD and normal tissues were analyzed using Gene Expression Profiling Interactive Analysis (GEPIA) database and were reconfirmed in clinical samples collected in our hospital. In addition, LINC01426 level in lung carcinoma cell lines was detected by quantitative real-time polymerase chain reaction (qRT-PCR) as well. The relationship between LINC01426 expression and the age, tumor node metastasis (TNM) staging, lymphatic metastasis, tumor differentiation, and overall survival of LUAD was analyzed. After intervening LINC01426 level in H1299 and PC9 cells, proliferative and metastatic changes were assessed by functional experiments. LINC01426 was upregulated in LUAD tissues and cell lines. Its level was closely linked to TNM staging, lymphatic metastasis, tumor differentiation, and overall survival of LUAD. Knockdown of LINC01426 suppressed proliferative and metastatic abilities in H1299 and PC9 cells. LINC01246 is upregulated in LUAD samples and predicts a poor prognosis. It drives malignant process of LUAD via stimulating proliferative and metastatic abilities.


Asunto(s)
Adenocarcinoma , Biomarcadores de Tumor , ARN Largo no Codificante , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Perfilación de la Expresión Génica , Humanos , Pulmón/metabolismo , Metástasis Linfática , Pronóstico , ARN Largo no Codificante/genética
6.
Anticancer Drugs ; 33(4): 406-412, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35266890

RESUMEN

EGFR exon 20 insertion mutation is a rare mutation subtype of EGFR mutations, with no approved treatment in China so far. The clinical treatments of advanced EGFR exon 20 insertion mutations in non-small cell lung cancer (NSCLC) are mainly based on EGFR-TKI, chemotherapy, ICI, and other therapies. However, the efficacy is not satisfactory. Aumolertinib is the third-generation EGFR-TKI independently developed in China, which has shown excellent efficacy and safety in phase 2 and 3 clinical trials. This study aimed to share a case of applying aumolertinib as the core combined with other treatments for a patient with multiple metastases in NSCLC with an uncommon site of EGFR exon 20 insertion mutations. The comprehensive treatment benefited the patient in terms of 10 months of progression-free survival and a significant improvement in quality of life. We discussed whether we could further explore the potential of aumolertinib in treating EGFR exon 20 insertion mutations through this case report.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Acrilamidas , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Receptores ErbB/genética , Exones , Humanos , Indoles , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Mutagénesis Insercional , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas , Calidad de Vida
7.
Sci Total Environ ; 807(Pt 3): 151050, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-34678369

RESUMEN

Iron (Fe) oxyhydroxides provide many functions in soils, mainly owing to their large surface area and high surface charge density. The reactivity of Fe oxyhydroxides is function of their mineralogical characteristics (e.g., crystallinity degree and crystal size). Detailed studies of these features are essential for predicting the stability and reactivity of these minerals within soil and sediments. The present study aimed to evaluate geochemical changes in Fe-rich tailings after the world's largest mining disaster in SE Brazil (in 2015) and to predict the potential environmental implications for the estuary. The mineralogical characteristics of the tailings were studied at three different times (2015, 2107, and 2019) to assess how an active redox environment affects Fe oxyhydroxides and to estimate the time frame within which significant changes occur. The study findings indicate a large decrease in the Fe oxyhydroxides crystallinity, which were initially composed (93%) of highly crystalline Fe oxyhydroxides (i.e., goethite and hematite) and 6.7% of poorly crystalline Fe oxyhydroxides (i.e., lepidocrocite and ferrihydrite). Within 4 years the mineralogical features of Fe oxyhydroxides had shifted, and in 2019 poorly crystalline Fe oxyhydroxides represented 47% of the Fe forms. Scanning electron microscope micrographs and the mean crystal size evidenced a decrease in particle size from 109 nm to 49 nm for goethite in the d111 direction. The changes in mean crystal size increased the reactivity of Fe oxyhydroxides, resulting in a greater number of interactions with cationic and anionic species. The decreased crystallinity and increased reactivity led to the compounds being more susceptible to reductive dissolution. Overall, the findings show that the decrease in crystallinity along with higher susceptibility to reductive dissolution of Fe oxyhydroxides can affect the fate of environmentally detrimental elements (e.g., phosphorus and trace metals) thereby increasing the concentration of these pollutants in estuarine soils and waters.


Asunto(s)
Hierro , Microscopía , Brasil , Oxidación-Reducción
8.
J Transl Med ; 19(1): 361, 2021 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-34419075

RESUMEN

Angiogenesis is the process of capillary sprouting from pre-existing vessels and it plays a critical role in the carcinogenic process of lung adenocarcinoma (LUAD). However, the association of angiogenesis regulators with the prognosis and progression of LUAD needs to be further elucidated. In this study, we adopted differential expression analysis, Cox proportional hazards (PH) regression analysis and experimental validation to identify angiogenesis regulators correlated with a poor prognosis, immune infiltration and cancer progression in LUAD. These results showed that the diagnostic and prognostic models based on COL5A2 and EPHB2 served as independent biomarkers with superior predictive ability. The patients in the high-risk group exhibited a worse prognosis in the TCGA cohort (P < 0.001, HR = 1.72, 95% CI 1.28-2.30), GSE310210 cohort (P = 0.005, HR = 2.87, 95% CI 1.46-5.61), and GSE31019 cohort (P = 0.01, HR = 2.14, 95% CI 1.19-3.86) than patients in the low-risk group. The high prognostic risk patients had a higher TMB (P < 0.001); higher fractions of M0 macrophages, neutrophils, NK cells resting, and T cells CD4 memory activated (P < 0.05); and higher expression of immune checkpoints PD-1, PDL-1, PDL-2, and B7H3 (P < 0.001). Patients in the high-risk group were more sensitive to chemotherapeutic drugs and molecular targeted drugs such as cisplatin, doxorubicin, gefitinib, and bosutinib (P < 0.0001). In addition, inhibition of COL5A2 and EPHB2 effectively suppressed the proliferation and migration of LUAD cells. The current study identified angiogenesis regulators as potential biomarkers and therapeutic targets for LUAD and may help to further optimize cancer therapy.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Adenocarcinoma del Pulmón/genética , Biomarcadores de Tumor , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Pronóstico
9.
Materials (Basel) ; 13(19)2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-33003621

RESUMEN

Mycotoxins in feed and food are highly toxic and pose a serious danger even at very low concentrations. The use of bentonites in animal diet can reduce toxin bioavailability. However, some mycotoxins like fumonisin B1 (FB1) form anionic species which excludes the use of negatively charged clays. Layered double hydroxides (LDH) with anion-exchange properties, in theory, can be perfect candidates to adsorb FB1. However, fundamental research on the use of LDH for mycotoxins removal is scarce and incomplete. Thus, the presented study was designed to explore such a possibility. The LDH materials with differing chemistry and layer charge were synthesized by co-precipitation both from metal nitrates and chlorides and were then tested for FB1 removal. XRD, FTIR, XPS, and chemical analysis were used for the LDH characterization and to obtain insight into the removal mechanisms. A higher adsorption capacity was observed for the Mg/Al LDH samples (~0.08-0.15 mol/kg) in comparison to the Mg/Fe LDH samples (~0.05-0.09 mol/kg) with no difference in removal efficiency between Cl and NO3 intercalated LDH. The adsorption capacity increased along with lower layer charge of Mg/Al and was attributed to the lower content of bonded carbonates and the increase of non-polar sites which led to matching between the adsorption domains of LDH with FB1. The FTIR analysis confirmed the negative effect of carbonates which hampered the adsorption at pH 7 and led to the highest adsorption at pH 5 (FB1 content ~15.8 ± 0.75 wt.%). The fast surface adsorption (1-2 min) was dominant and XRD analysis of the basal spacing indicated that no FB1 intercalation occurred in the LDH. The XPS confirmed a strong interaction of FB1 with Mg sites of LDH at pH 5 where the interaction with FB1 carboxylate moieties COO- was confirmed. The research confirmed a high affinity and selectivity of LDH structures towards anionic forms of FB1 mycotoxin.

10.
Toxins (Basel) ; 12(1)2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-31906445

RESUMEN

Carcinogenic aflatoxins can be inactivated by smectites (e.g., montmorillonite) through adsorption and degradation. Proteins in gastric fluids can reduce smectite's adsorption capacity for aflatoxins. The objective of this study was to evaluate the efficiency of smectites modified with organic nutrients in restricting the influence of proteins on aflatoxin adsorption. Arginine, histidine, choline, lysine, and vitamin B1 were selected to occupy part of the interlayer space of montmorillonite to achieve a smectite structure more selective for aflatoxin adsorption, but not for the large protein molecules. The unmodified montmorillonite had a maximum adsorption capacity of 0.2 mol/kg in the presence of pepsin. The vitamin B1-montmorillonite showed significant improvements in the aflatoxin affinity constant from 0.065 to 0.201 µ M - 1 and the aflatoxin adsorption to 0.56 mol/kg. Choline-montmorillonite and histidine-montmorillonite showed a moderate increase in AfB1 adsorption. Arginine-montmorillonite and lysine-montmorillonite showed a slight increase in the adsorption capacity, but did not improve the affinity constant. The XRD results indicated that pepsin could still access the interlayer of nutrient-montmorillonite complexes. The intercalation of organic nutrients into the interlayer space of montmorillonite improved the AfB1 adsorption by restricting the adsorption of pepsin.


Asunto(s)
Aflatoxinas/química , Pepsina A/química , Silicatos/química , Adsorción , Aflatoxina B1 , Bentonita
11.
Surg Laparosc Endosc Percutan Tech ; 30(2): 173-179, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31764861

RESUMEN

BACKGROUND: With its growing popularity and potential outcome, complete uniportal thoracoscopic (CUT) surgery has been used in the treatment of thoracic diseases. This study aimed to summarize a personal experience of CUT anatomic lung resection with systematic mediastinal lymphadenectomy (CUT-ALR-SML) for non-small cell lung cancer (NSCLC) and to evaluate the feasibility and safety of CUT-ALR-SML in our institute. MATERIALS AND METHODS: A total of 326 patients with NSCLC were chosen to undergo CUT-ALR-SML in our institute from August 2013 to July 2018. Data such as clinicopathologic characteristics and perioperative outcomes were reviewed in this article. RESULTS: For the 326 cases of ALR, the specific procedures and the corresponding number of cases were as follows: segmentectomy, 90; lobectomy, 218; sleeve lobectomy, 9; ipsilateral lobe combined with segment resected synchronously (i-L+S), 6; and pneumonectomy, 3. A total of 31 cases required conversion to open surgery, and 4 cases were converted to multiportal thoracoscopic surgery. All patients underwent SML. The average mediastinal lymph node stations and mediastinal lymph nodes dissected under CUT-ALR-SML were 3.3±1.4 and 9.6±8.4, respectively. Approximately 99.7% of the patients acquired free resection margins. A total of 42 (12.9%) patients suffered from postoperative complications, and 1 patient died of pneumonia during the perioperative period. CONCLUSIONS: Complete uniportal ALR, particularly for segmentectomy and lobectomy is safe and feasible with low complication rates and excellent free resection margin rates. SML during complete uniportal thoracoscopic surgery adequately assesses the N2 lymph node. However, further studies need to be conducted to evaluate the role of CUT-ALR-SML in the treatment of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/cirugía , Escisión del Ganglio Linfático/efectos adversos , Neumonectomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Toracoscopía/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios de Factibilidad , Femenino , Humanos , Neoplasias Pulmonares/patología , Escisión del Ganglio Linfático/métodos , Masculino , Persona de Mediana Edad , Neumonectomía/métodos , Estudios Retrospectivos , Toracoscopía/métodos
12.
Sci Rep ; 9(1): 13049, 2019 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-31506467

RESUMEN

Acidithiobacillus ferrooxidans, a chemolithoautotrophic bacterium, is well known for its mineral oxidizing properties. The current study combines experimental and whole genome sequencing approaches to investigate an iron oxidizing, extreme acidophilic bacterium, A. ferrooxidans isolate (IO-2C) from an acid seep area near Carlos, TX, USA. Strain IO-2C was capable of oxidizing iron i.e. iron sulphate and iron ammonium sulphate yielding shwertmannite and jarosite minerals. Further, the bacterium's genome was sequenced, assembled and annotated to study its general features, structure and functions. To determine genetic heterogeneity, it was compared with the genomes of other published A. ferrooxidans strains. Pan-genome analysis displayed low gene conservation and significant genetic diversity in A. ferrooxidans species comprising of 6926 protein coding sequences with 23.04% (1596) core genes, 46.13% (3195) unique and 30.82% (2135) accessory genes. Variant analysis showed >75,000 variants, 287 of them with a predicted high impact, in A. ferrooxidans IO-2C genome compared to the reference strain, resulting in abandonment of some important functional key genes. The genome contains numerous functional genes for iron and sulphur metabolism, nitrogen fixation, secondary metabolites, degradation of aromatic compounds, and multidrug and heavy metal resistance. This study demonstrated the bio-oxidation of iron by newly isolated A. ferrooxidans IO-2C under acidic conditions, which was further supported by genomic analysis. Genomic analysis of this strain provided valuable information about the complement of genes responsible for the utilization of iron and tolerance of other metals.


Asunto(s)
Acidithiobacillus/genética , Variación Genética , Genoma Bacteriano , Genómica , Microbiología Ambiental , Genómica/métodos , Hierro/metabolismo , Oxidación-Reducción , Filogenia , Análisis de Secuencia , Secuenciación Completa del Genoma
13.
J Environ Sci (China) ; 80: 267-276, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30952344

RESUMEN

Metal ions and fiber are common compounds in the livestock and poultry manure, which will affect the fate of organic compounds in aqueous environment. However, limited research has addressed the effect of coexisting metal ions and fiber on the biodegradation of sulfonamide antibiotics. Accordingly, a compositing study was performed to assess the effect of metal ions (Fe3+ and Cu2+) on the biodegradation of sulfadimethoxine sodium salt (SDM) in the presence of fiber. The enhanced adsorption of SDM onto fiber in the presence of metal ions can be attributed to the π+-π electron donor acceptor (EDA) interaction. The microbial (Phanerochaete chrysosprium) could easily attach onto fiber forming attached microbial, and the degradation rates of SDM of immobilized bacteria in the presence of Fe3+ were 100%, which were significantly higher than those of free bacteria (45%). This study indicates that Fe3+ and fiber could enhance the biodegradation of SDM. Fiber acts as adsorbent, carrier, and substrate which enhanced the removal of SDM.


Asunto(s)
Biodegradación Ambiental , Sulfonamidas/química , Contaminantes Químicos del Agua/química , Adsorción , Antibacterianos , Bacterias , Iones/química , Cinética , Estiércol , Metales/química , Sulfonamidas/análisis , Contaminantes Químicos del Agua/análisis
14.
Sci Total Environ ; 647: 99-109, 2019 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-30077859

RESUMEN

The long-term effect of using treated wastewater is not clearly defined: some researchers argue that it is better than freshwater for the soil health; others disapprove, claiming that irrigation with unconventional water resources causes soil degradation. This study assesses the impact of irrigation with non-traditional water on the chemical and mineralogical properties of a calcareous clayey soil from West Texas. The exponential rise in population and the realities of climate change contribute to the global increase in freshwater scarcity: non-conventional water sources, such as treated wastewater (TWW) and brackish groundwater (BGW), offer potentially attractive alternative water resources for irrigated agriculture. For this research, the differences between TWW and BGW were addressed by collecting and analyzing water samples for salt and nutrient content. Soil samples from three horizons (Ap, A, and B) were obtained from three different fields: Rainfed (RF), BGW irrigated, and TWW irrigated. Soil was analyzed for texture, salinity, sodicity, and carbon content. Clay mineralogy of the three different fields was analyzed using the B-horizons. The outcomes from the analysis showed that the BGW from the Lipan aquifer has higher salinity and is harder compared to TWW. Although the exchangeable sodium percentage (ESP), sodium adsorption ratio (SAR), and electroconductivity (EC) increased marginally compared to the control soil (RF), the soils were in good health, all the values of interest (SAR < 13, ESP < 15, pH < 8.5, and EC < 4) were low, indicating no sodicity or salinity problems. Smectite, illite, and kaolinite were identified in the three B-horizon samples using bulk X-ray diffraction (XRD). Overall, no major changes were observed in the soil. Thus, TWW and BGW are viable replacements for freshwater irrigation in arid and semi-arid regions.

15.
Chem Res Toxicol ; 30(9): 1694-1701, 2017 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-28768106

RESUMEN

Previously, a calcium montmorillonite clay (NovaSil) included in the diet of animals has been shown to bind aflatoxin B1 (AfB1) and reduce the symptoms of aflatoxicosis. To investigate and improve the capacity and efficacy of clay-based materials as aflatoxin sorbents, we developed and tested calcium and sodium montmorillonite clays amended with nutrients including l-carnitine and choline. Also, we determined the sorption of AfB1 by isothermal analysis and tested the ability of these amended sorbents to protect adult hydra from AfB1 toxicity. The results showed that exchanging montmorillonite clays with l-carnitine and choline inhibited swelling of the clays and increased the sorption capacity and efficacy of clay surfaces for AfB1. Results from dehydroxylated and heat-collapsed clays suggested that AfB1 was primarily adsorbed in the clay interlayer, as predicted from thermodynamic calculations and computational modeling. The hydra bioassay further indicated that the modified clays can significantly protect adult hydra from AfB1 with as low as 0.005% clay inclusion. This enterosorbent therapy may also be applied to screen hazardous chemicals such as pesticides and PAHs based on similar sorption mechanisms. Taken together, enterosorbent therapy could be delivered in nutritional supplements, foods that are vulnerable to aflatoxin contamination, flavored liquids and animal feeds during emergencies and outbreaks of acute aflatoxicosis, and as a screening model for hazardous environmental chemicals.


Asunto(s)
Aflatoxina B1/química , Silicatos de Aluminio/química , Sustancias Peligrosas/química , Adsorción , Animales , Bentonita/química , Carnitina/química , Colina/química , Arcilla , Dieta , Contaminación de Alimentos/análisis , Modelos Moleculares , Termodinámica
16.
Int J Biol Macromol ; 92: 1191-1196, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27498417

RESUMEN

Chitosan-montmorillonite composites can provide hydrophobicity and amino groups to enhance the performances of montmorillonite in wastewater treatment. In this paper, low molar mass chitosan (LC) and medium molar mass chitosan (MC) were selected to intercalate a sodium montmorillonite (Mt). The adsorption isotherm of LC and MC on the Mt and the pH dependency were measured. Thermo X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the chitosan-Mt composites. Results showed that with hydrochloric acid as the solvent of chitosans, increasing pH from 3 to 5.5 enhanced the adsorption of both LC and MC on the Mt, and when the equilibrium concentration of chitosans approached 300mg/L at pH 5.5, the amount of adsorbed chitosan reached the highest level of 0.203mg/mg for LC and 0.190mg/mg for MC, respectively. When the Mt was saturated with the chitosan, the amino groups on the chitosan were bonded with the Mt through electrostatic interaction and there was monolayer of the chitosan in the interlayer space of Mt, which were confirmed by FTIR spectra and XRD patterns, respectively.


Asunto(s)
Bentonita/química , Quitosano/química , Adsorción , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Electricidad Estática , Termodinámica , Purificación del Agua
17.
J Hazard Mater ; 317: 237-245, 2016 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-27285595

RESUMEN

Arsenic immobilization in acid mine drainage (AMD) is required prior to its discharge to safeguard aquatic organisms. Zero-valent aluminum (ZVAl) such as aluminum beverage cans (AlBC) was used to induce the oxidation of As(III) to As(V) and enhance the subsequent As removal from an artificially prepared AMD. While indiscernible As(III) oxidation was found in aerated ZVAl systems, the addition of 0.10-0.55mM Fe(II) or Fe(III) into the AMD significantly promoted the As(V) production. Reactions between Fe(II) and H2O2, which was produced through an oxidative reaction of ZVAl with dissolved oxygen, generated OH radicals. Such OH radicals subsequently induced the As(III) oxidation. Over the course of the Fenton like reaction, ZVAl not only directly generated the H2O2, but indirectly enhanced the OH radical production by replenishing Fe(II). Arsenite oxidation in the aerated ZVAl/Fe and AlBC/Fe systems followed zero- and first-order kinetics. Differences in the kinetic reactions of ZVAl and AlBC with respect to As(III) oxidation were attributed to higher productive efficiency of the oxidant in the AlBC systems. After the completion of As(III) oxidation, As(V) could be removed simultaneously with Al(III) and Fe(III) by increasing solution's pH to 6 to produce Al/Fe hydroxides as As(V) scavengers or to form Al/Fe/As co-precipitates.

18.
Food Chem ; 173: 629-39, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25466069

RESUMEN

Three commercially available vibrational spectroscopic techniques, including Raman, Fourier transform near infrared reflectance (FT-NIR), and Fourier transform infrared (FTIR) were evaluated to help users determine the spectroscopic method best suitable for aflatoxin analysis in maize (Zea mays L.) grain based on their relative efficiency and predictive ability. Spectral differences of Raman and FTIR spectra were more marked and pronounced among aflatoxin contamination groups than those of FT-NIR spectra. From the observations and findings in our current and previous studies, Raman and FTIR spectroscopic methods are superior to FT-NIR method in terms of predictive power and model performance for aflatoxin analysis and they are equally effective and accurate in predicting aflatoxin concentration in maize. The present study is considered as the first attempt to assess how spectroscopic techniques with different physical processes can influence and improve accuracy and reliability for rapid screening of aflatoxin contaminated maize samples.


Asunto(s)
Aflatoxinas/análisis , Zea mays/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectroscopía Infrarroja Corta/métodos , Espectrometría Raman/métodos , Vibración
19.
Front Microbiol ; 5: 102, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24672518

RESUMEN

The identification of aflatoxins as human carcinogens has stimulated extensive research efforts, which continue to the present, to assess potential health hazards resulting from contamination of the human food supply and to minimize exposure. The use of biomarkers that are mechanistically supported by toxicological studies will be important tools for identifying stages in the progression of development of the health effects of environmental agents. miRNAs are small non-coding mRNAs that regulate post-transcriptional gene expression. Also, they are molecular markers of cellular responses to various chemical agents. Growing evidence has demonstrated that environmental chemicals can induce changes in miRNA expression. miRNAs are good biomarkers because they are well defined, chemically uniform, restricted to a manageable number of species, and stable in cells and in the circulation. miRNAs have been used as serological markers of HCC and other tumors. The expression patterns of different miRNAs can distinguish among HCC-hepatitis viruses related, HCC cirrhosis-derivate, and HCC unrelated to either of them. The main objective of this review is to find unreported miRNAs in HCC related to other causes, so that they can be used as specific molecular biomarkers in populations exposed to aflatoxins and as early markers of exposure, damage/presence of HCC. Until today specific miRNAs as markers for aflatoxins-exposure and their reliability are currently lacking. Based on their elucidated mechanisms of action, potential miRNAs that could serve as possible markers of HCC by exposure to aflatoxins are miR-27a, miR-27b, miR-122, miR-148, miR-155, miR-192, miR-214, miR-221, miR-429, and miR-500. Future validation for all of these miRNAs will be needed to assess their prognostic significance and confirm their relationship with the induction of HCC due to aflatoxin exposure.

20.
J Environ Sci (China) ; 24(5): 919-25, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22893971

RESUMEN

Lead (Pb) chemical fixation is an important environmental aspect for human health. Phosphate rocks (PRs) were utilized as an adsorbent to remove Pb from aqueous solution. Raw PRs and oxalic acid-activated PRs (APRs) were used to investigate the effect of chemical modification on the Pb-binding capacity in the pH range 2.0-5.0. The Pb adsorption rate of all treatments above pH 3.0 reached 90%. The Pb binding on PRs and APRs was pH-independent, except at pH 2.0 in activated treatments. The X-ray diffraction analysis confirmed that the raw PRs formed cerussite after reacting with the Pb solution, whereas the APRs formed pyromorphite. The Fourier Transform Infrared spectroscopy analysis indicated that carbonate (CO3(2-)) in raw PRs and phosphate (PO4(3)) groups in APRs played an important role in the Pb-binding process. After adsorption, anomalous block-shaped particles were observed by scanning electron microscopy with energy dispersive spectroscopy. The X-ray photoelectron spectroscopy data further indicated that both chemical and physical reactions occurred during the adsorption process according to the binding energy. Because of lower solubility of pyromorphite compared to cerussite, the APRs are more effective in immobilizing Pb than that of PRs.


Asunto(s)
Sedimentos Geológicos/química , Plomo/aislamiento & purificación , Ácido Oxálico/química , Fosfatos/química , Adsorción , China , Concentración de Iones de Hidrógeno , Iones , Microscopía Electrónica de Rastreo , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
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