Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
World J Gastrointest Surg ; 16(6): 1883-1893, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38983339

RESUMO

BACKGROUND: Gastric cancer is a common malignant tumor of the digestive system worldwide, and its early diagnosis is crucial to improve the survival rate of patients. Indocyanine green fluorescence imaging (ICG-FI), as a new imaging technology, has shown potential application prospects in oncology surgery. The meta-analysis to study the application value of ICG-FI in the diagnosis of gastric cancer sentinel lymph node biopsy is helpful to comprehensively evaluate the clinical effect of this technology and provide more reliable guidance for clinical practice. AIM: To assess the diagnostic efficacy of optical imaging in conjunction with indocyanine green (ICG)-guided sentinel lymph node (SLN) biopsy for gastric cancer. METHODS: Electronic databases such as PubMed, Embase, Medline, Web of Science, and the Cochrane Library were searched for prospective diagnostic tests of optical imaging combined with ICG-guided SLN biopsy. Stata 12.0 software was used for analysis by combining the "bivariable mixed effect model" with the "midas" command. The true positive value, false positive value, false negative value, true negative value, and other information from the included literature were extracted. A literature quality assessment map was drawn to describe the overall quality of the included literature. A forest plot was used for heterogeneity analysis, and P < 0.01 was considered to indicate statistical significance. A funnel plot was used to assess publication bias, and P < 0.1 was considered to indicate statistical significance. The summary receiver operating characteristic (SROC) curve was used to calculate the area under the curve (AUC) to determine the diagnostic accuracy. If there was interstudy heterogeneity (I 2 > 50%), meta-regression analysis and subgroup analysis were performed. RESULTS: Optical imaging involves two methods: Near-infrared (NIR) imaging and fluorescence imaging. A combination of optical imaging and ICG-guided SLN biopsy was useful for diagnosis. The positive likelihood ratio was 30.39 (95%CI: 0.92-1.00), the sensitivity was 0.95 (95%CI: 0.82-0.99), and the specificity was 1.00 (95%CI: 0.92-1.00). The negative likelihood ratio was 0.05 (95%CI: 0.01-0.20), the diagnostic odds ratio was 225.54 (95%CI: 88.81-572.77), and the SROC AUC was 1.00 (95%CI: The crucial values were sensitivity = 0.95 (95%CI: 0.82-0.99) and specificity = 1.00 (95%CI: 0.92-1.00). The Deeks method revealed that the "diagnostic odds ratio" funnel plot of SLN biopsy for gastric cancer was significantly asymmetrical (P = 0.01), suggesting significant publication bias. Further meta-subgroup analysis revealed that, compared with fluorescence imaging, NIR imaging had greater sensitivity (0.98 vs 0.73). Compared with optical imaging immediately after ICG injection, optical imaging after 20 minutes obtained greater sensitivity (0.98 vs 0.70). Compared with that of patients with an average SLN detection number < 4, the sensitivity of patients with a SLN detection number ≥ 4 was greater (0.96 vs 0.68). Compared with hematoxylin-eosin (HE) staining, immunohistochemical (+ HE) staining showed greater sensitivity (0.99 vs 0.84). Compared with subserous injection of ICG, submucosal injection achieved greater sensitivity (0.98 vs 0.40). Compared with 5 g/L ICG, 0.5 and 0.05 g/L ICG had greater sensitivity (0.98 vs 0.83), and cT1 stage had greater sensitivity (0.96 vs 0.72) than cT2 to cT3 clinical stage. Compared with that of patients ≤ 26, the sensitivity of patients > 26 was greater (0.96 vs 0.65). Compared with the literature published before 2010, the sensitivity of the literature published after 2010 was greater (0.97 vs 0.81), and the differences were statistically significant (all P < 0.05). CONCLUSION: For the diagnosis of stomach cancer, optical imaging in conjunction with ICG-guided SLN biopsy is a therapeutically viable approach, especially for early gastric cancer. The concentration of ICG used in the SLN biopsy of gastric cancer may be too high. Moreover, NIR imaging is better than fluorescence imaging and may obtain higher sensitivity.

2.
ACS Sens ; 9(6): 3423-3432, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38803215

RESUMO

Precise three-dimensional (3D) bioprinting designs enable the fabrication of unique structures for 3D-cell culture models. There is still an absence of real-time detection tools to effectively track in situ 3D-cell performance, hindering a comprehensive understanding of disease progression and drug efficacy assessment. While numerous bioinks have been developed, few are equipped with internal sensors capable of accurate detection. This study addresses these challenges by constructing a 3D-bioprinted hepar-on-a-chip embedded with graphene quantum dot-capped gold nanoparticle-based plasmonic sensors, featuring strong surface-enhanced Raman scattering (SERS) enhancement, biostability, and signal consistency. Such an integrated hepar-on-a-chip demonstrates excellent capability in the secretion of liver function-related proteins and the expression of drug metabolism and transport-related genes. Furthermore, the on-site detection of cell-secreted biomarker glutathione transferase α (GST-α) was successfully achieved using the plasmonic probe, with a dynamic linear detection range of 20-500 ng/mL, showcasing high anti-interference and specificity for GST-α. Ultimately, this integrated hepar-on-a-chip system offers a high-quality platform for monitoring liver injury.


Assuntos
Ouro , Grafite , Pontos Quânticos , Grafite/química , Humanos , Ouro/química , Pontos Quânticos/química , Nanopartículas Metálicas/química , Bioimpressão/métodos , Dispositivos Lab-On-A-Chip , Impressão Tridimensional , Análise Espectral Raman/métodos , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação
4.
Appl Opt ; 63(6): 1546-1552, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38437367

RESUMO

Underwater wireless optical communication (UWOC) has attracted considerable interest owing to its capability of high data rates and low latency. As a crucial component of UWOC, the transmission characteristics of an underwater channel directly impact the system's performance metrics. However, the existing channel models cannot exactly capture the underwater channel states, thus degrading the observability of channel states. This paper proposes a hybrid-field channel model containing both far-field and near-field path components, in which the signal-dependent shot noise (SDSN) is incorporated as well to accurately describe the underwater channel behavior. Then an improved orthogonal matching pursuit (I-OMP) algorithm that estimates the far-field and near-field path components independently with different transform matrices is developed to obtain the underwater channel state. The performance analyses show that I-OMP can improve the estimation accuracy of underwater channels by iteratively minimizing the mean square error (MSE) and utilizing two different transform matrices, demonstrating the advantage of the proposed I-OMP over the existing methods.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 312: 124051, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38368820

RESUMO

We developed a highly efficient, ultra-sensitive, and selective dual detection sensor for hypochlorite (ClO-) and sulfite (SO32-) ions based on surface-enhanced Raman scattering (SERS) spectroscopy. 3,3',5,5'-Tetramethylbenzidine (TMB) is oxidized by ClO- under acidic conditions to diazotized oxTMB that, when electrostatically adsorbed onto Au nanoparticles (NPs), produces a strong Raman signal at 1605 cm-1. Meanwhile, oxTMB is reduced to TMB by SO32-, which significantly reduces the Raman signal. The linear detection range of the proposed sensor is 10-10 to 10-6 M with a detection limit of 59 pM for ClO- and 10-9 to 10-5 M with a detection limit of 5.4 nM for SO32-. In addition, the sensor was successfully applied to detect ClO- and SO32- in water samples.

6.
Sci Total Environ ; 914: 170027, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218498

RESUMO

We report a surface magnetic solid-phase extraction-surface-enhanced Raman scattering (SMSPE-SERS) method based on silver-nanoparticle-coated Fe3O4/chitosan (Fe3O4/CS@Ag) microspheres as the substrate, and this method integrates all steps from sample pretreatment to detection. Fe3O4/CS was synthesized by a one-step solvothermal method in which chitosan (CS) was used as a surface modifier and adsorbent. Fe3O4/CS@Ag microspheres exhibit both adsorption ability and SERS activity. Therefore, we used the SMSPE-SERS method to detect pesticide residues on fruit peel. The procedures of capturing, separating and enriching pesticides, as well as detection, are all integrated. In addition, the SERS substrate allows label-free detection of thiram pesticide in both fruit peel and apple juice. Owing to the uniform distribution of Ag NPs and the adsorption ability of CS, the thiram-detection sensitivity was sufficiently high to detect the lowest concentration of 1.2 ng/cm2, which was significantly lower than the maximum thiram residue limit (7 µg/cm2) in fruits. The method was comparable to high-performance liquid chromatography with recovery ranging from 86.60 to 109.69 %.

7.
Front Chem ; 11: 1286290, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38260045

RESUMO

Traditional combat sports equipment usually uses synthetic materials, such as polyurethane and synthetic leather. Although these materials have a certain degree of strength and durability, they have poor flexibility and antibacterial properties, making it difficult to provide stable support and protection for athletes. In order to enhance the antibacterial properties and flexibility of sports equipment and reduce the risk of injuries to athletes, this article conducts in-depth research on the development of combat sports equipment using conjugated polymers. This article first selects polypropylene (PP) as the base material for sports equipment for combat athletes, and uses the gas phase polymerization method to prepare the material; then uses chitosan as an antimicrobial agent and uses the oxidative degradation method to prepare it; after that, this article coats the chitosan antibacterial agent on the prepared PP material, and uses a combination of dipping and calendering for antibacterial treatment; finally, this article uses the spunbond melt-blown composite method to fill and combine the top equipment of combat athletes to achieve the structural design of sports equipment. In order to verify the effectiveness of the equipment, this article conducted equipment performance testing and sports injury simulation. The results showed that the average diameter of the antibacterial zone of this sports equipment reached more than 1 mm, and in the injury risk test, the risk of athletes' joint and muscle injuries was reduced by 16.9% and 20.5% respectively. Research shows that developing combat sports equipment based on conjugated polymers can help reduce the risk of injury to athletes and improve the safety of combat sports.

8.
Sci Total Environ ; 830: 154598, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35307417

RESUMO

Hexavalent chromium (Cr(VI)) pollution in the water system has seriously endangered human health and the environment. Herein, we propose a rapid, simple and sensitive surface-enhanced resonance Raman scattering (SERRS) sensor with the bifunctional negatively charged gold nanoparticles ((-)AuNPs) which employ as not only the oxidoreductase-like nanozyme but also the substrate to determine Cr(VI). (-)AuNPs effectively promoted the conversion of 3,3',5,5'-tetramethylbenzidine (TMB) into the blue product of 3,3',5,5'-tetramethylbenzidine diamine (oxTMB) in the presence of Cr(VI) and generated a strong SERRS signal at 1611 cm-1. According to this principle, the Raman intensity difference at 1611 cm-1 exhibited a satisfactory linear relationship with the logarithm of the Cr(VI) concentration from 10-5 to 10-9 M with a low limit of detection (LOD) of 0.4 nM. In addition, the possible SERRS enhancement mechanism, selectivity and reproducibility were also investigated. What's more, the SERRS platform was successfully applied in the complicated water samples, which was anticipated to become a promising analytical method for monitoring of Cr(VI) in the environment.


Assuntos
Ouro , Nanopartículas Metálicas , Cromo , Humanos , Reprodutibilidade dos Testes , Análise Espectral Raman/métodos , Água
9.
J Hazard Mater ; 424(Pt A): 127303, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34601405

RESUMO

The development of convenient assays for the determination of hydrazine (N2H4) has drawn significant attention due to the high toxicity of this substance. Herein, we developed a concise, rapid and ultrasensitive surface-enhanced Raman scattering (SERS) sensor for N2H4 detection based on alpha-cyclodextrin-silver nanoparticles (α-CD-AgNPs) modified by 4-mercaptobenzaldehyde (4-MBA). The 4-MBA molecules can specifically capture the N2H4 molecules and undergo a Schiff base reaction. As a result, this induces the aggregation of nanoparticles and generates a new characteristic peak at 1529 cm-1 that is attributed to CN and CC vibrations. Compared with noble metal nanoparticles, 4-MBA not only formed AgS bonds but could also be fixed in the cavity of cyclodextrin to produce a more stable and stronger SERS signal. The SERS intensity at 1529 cm-1 and the logarithm of the concentration of N2H4 presented a good linear relationship from 10-9 to 10-7 M with an unprecedented limit of detection (LOD) of 38 pM. The proposed SERS sensor exhibited satisfactory selectivity and reproducibility and was applied to detect N2H4 in real and complex water samples. We expect this assay to be a promising alternative tool for the on-site detection of N2H4.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Hidrazinas , Reprodutibilidade dos Testes , Bases de Schiff , Prata
10.
Materials (Basel) ; 14(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34640144

RESUMO

The purpose of this study was to develop a flexible substrate methylcellulose-decorated silver nanoparticles (MC/Ag NPs) film and explore its application in fruits and vegetables by surface enhanced Raman spectroscopy (SERS) technology for rapid detection of pesticides. The performance of the MC/Ag NPs film substrate was characterized by Nile blue A (NBA), and the detection limit was as low as 10-8 M. The substrate also exhibited satisfactory Raman signal strength after two months of storage. The impressive sensitivity and stability were due to the excellent homogeneity of the silver nanoparticles that were grown in situ in the methylcellulose matrix, which generated "hot spots" between the silver nanoparticles without a large amount of aggregation, and resulted in the ultra-high sensitivity and excellent stability of the MC/Ag NPs film substrate. The MC/Ag NPs film substrate was used to detect thiram pesticides on tomato and cucumber peels, and the minimum detectable level of thiram was 2.4 ng/cm2, which was much lower than the maximum residue level. These results indicate that the MC/Ag NPs film is sensitive to rapid detection of multiple pesticides in food.

11.
Materials (Basel) ; 14(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672047

RESUMO

Noble metal-semiconductor nanocomposites have received extensive attention in Surface Enhanced Raman Scattering (SERS) due to their unique properties. In this paper, the Ag-ZnO nanocomposites are prepared by hydrothermal growth and simple chemical reduction immersion. The synthesized nanocomposite material simultaneously integrates the individual enhancement effects of the two materials in the SERS, such as the electromagnetic enhancement of silver nanoparticles and the chemical enhancement of ZnO semiconductor materials. Using this substrate, Rhodamine 6G molecules with a concentration as low as 10-8 M can be detected, and the coupling reaction of PATP can be effectively promoted. The nanocomposite materials prepared by selecting appropriate semiconductor materials and metal materials combined, could be potentially applied, as SERS substrates, in certain catalytic reactions.

12.
Int J Biol Sci ; 16(14): 2704-2711, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33110390

RESUMO

Statins, known as HMG-CoA reductase (HMGCR) inhibitors, have primarily been utilized for metabolic and angiographic medical applications because of their cholesterol-lowering effects. Similar to other drugs, statins may also induce a series of potential side effects. Statins inhibit the HMGCR (rate-limiting enzyme) activity in early stages of mevalonate pathway and then indirectly affect a number of intermediate products, including non-sterol isoprenoids (coenzyme Q10, dolichol etc.), which can result in impaired functions of body organs. Recently, scores of studies have uncovered additional functional mechanisms of statins in other diseases, such as diabetes mellitus, nervous system diseases, coronary heart disease, inflammation and cancers. This review aims to summarize the positive and adverse mechanisms of statin therapy. Statin care should be taken in the treatment of many diseases including cancers. Since the underlying mechanisms are not fully elucidated, future studies should spend more time and efforts on basic research to explore the mechanisms of statins.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Doença das Coronárias/tratamento farmacológico , Diabetes Mellitus/induzido quimicamente , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , Doenças do Sistema Nervoso/tratamento farmacológico
13.
Clin Transl Med ; 10(1): 57-73, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32508020

RESUMO

BACKGROUND: Breast cancer is the leading cause of death among women. Cisplatin is an effective drug for breast cancer, but resistance often develops during long term chemotherapy. While the mechanism of chemotherapy resistance is still not fully understood. METHODS: Survival analyses of ATP7A and ATP7B were used to evaluate their effects on the development of Breast invasive carcinoma (BRCA). Immunostaining, flow cytometry, and IC50 assay were utilized to examine the effects of ATP7A-siRNA combined with cisplatin on apoptosis in breast cancer cells. Q-PCR, western blotting, and dual-luciferase assay were employed to confirm ATP7A is a novel target gene of miR-148a-3p. RESULTS: In this current study, we identified knocking-down ATP7A could enhance cytotoxicity treatment of cisplatin in breast cancer cells. We also demonstrated miR-148a-3p overexpression in BRCA cells increased the sensitivity to cisplatin, and subsequently enhanced DNA damage and apoptosis. Moreover, we found ATP7A is a novel target gene of miR-148a-3p. In brief, our results showed miR-148a could accelerate chemotherapy induced-apoptosis in breast cancer cells by inhibiting ATP7A expression. CONCLUSIONS: Our results highlight that inhibition of ATP7A is a potential strategy for targeting breast cancer resistant to cisplatin, and we provided an interesting method to compare the involvement of various genes in the assessment of cisplatin resistance.

14.
Onco Targets Ther ; 13: 1613-1624, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32110057

RESUMO

BACKGROUND: Circular RNAs (circRNAs) play important regulatory roles in cancer development. However, the mechanisms by which circRNAs regulate gene expression in gastric cancer (GC) remain unclear. METHODS: Human GC samples and their matched normal adjacent tissues were obtained from 30 patients to assess the expression of circHIPK3 and its relationship with GC proliferation and migration. A series of in vitro and in vivo functional experiments were carried out to elucidate the role of circHIPK3 in GC proliferation and migration, and its underlying molecular mechanisms. RESULTS: Using a circRNA microarray we found a circRNA termed circHIPK3 that performed a significant regulatory role in GC. circHIPK3 was further confirmed to be upregulated in all GC tissues and cells tested. Furthermore, circHIPK3 levels were associated with Tumor & Lymph Node & Metastasis(TNM) stage (P = 0.032). The area under the receiver operating characteristic curve (ROC) was 0.743 (95% confidence interval 0.615-0.872; P = 0.001). CCK-8, colony formation, Transwell and EdU assays were performed to evaluate the effects of circHIPK3 on cell proliferation and migration in GC. Moreover, circHIPK3 was identified as a sponge of miR-107, and as such it regulated brain-derived neurotrophic factor (BDNF), which plays a pivotal role in the development of GC. CONCLUSION: circHIPK3 represents a novel potential biomarker and therapeutic target of GC.

15.
Nanoscale Adv ; 2(8): 3460-3466, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36134259

RESUMO

Semiconductor materials are favoured in the field of photocatalysis due to their unique optoelectronic properties. When a semiconductor is excited by external energy, electrons will transition through the band gap, providing electrons or holes for the reaction. This is similar to the chemical enhancement mode of a catalytic reaction initiated by the rough noble metal on the surface excited by plasmon resonance. In this study, different types of semiconductor silicon loaded with silver nanoparticles were used as SERS substrates. SERS detection of p-aminothiophenol (PATP) and p-nitrothiophenol (PNTP) probe molecules was performed using typical surface plasmon-driven coupling reactions, and the mechanism of optical drive charge transfer in semiconductor-metal-molecular systems was investigated. Scanning electron microscopy and plasmon luminescence spectroscopy were used to characterize the silver deposited on the substrate surface. Mapping technology and electrochemistry were used to characterize the photocatalytic reaction of the probe molecules. This study proposed a mechanism for the coupling reaction of "hot electrons" and "hot holes" on the surface of plasmon-driven molecules and provides a method for preparing a stable SERS substrate.

16.
Math Biosci Eng ; 16(6): 7375-7383, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31698617

RESUMO

The heparan sulfate proteoglycan agrin is known to accumulate in the context of hepatocellular carcinoma (HCC). Agrin is important for neoangiogenesis in HCC tissues, and is incorporated into newly formed vasculature, but exactly how agrin contributes to the pathology of HCC remains to be fully defined. We therefore examined the clinical relevance of agrin as it pertains to HCC progression and prognosis using tissue sections from a total of 313 HCC patients. We found that agrin expression was detectable in more HCC samples (25.4% vs. 77.1%; P < 0.05) compared to normal tissue controls. Agrin expression was notably linked to tumor size (P = 0.041) and metastasis (P = 0.034). The recurrence free survival rate of agrin-positive HCC patients was considerably lower than that of agrin-negative patients (P = 0.001). We further confirmed HCC survival to be independently correlated with tumor size, metastasis, microvascular invasion and edmondson Grade via a Cox regression analysis. Upregulation of Agrin may play a crucial role in HCC progression. Together our results suggest that Agrin has the potential to be used as a prognostic indicator in predicting HCC patient outcomes.


Assuntos
Agrina/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica , Prognóstico , Análise Serial de Tecidos
17.
J Hazard Mater ; 379: 120701, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31299630

RESUMO

The influence of elemental sulfur (S(0)) amendment on methylmercury (MeHg) accumulation in rice and the chemical form of Hg in the rhizosphere were investigated under waterlogged conditions in Hg-contaminated soil (the majority of the Hg (˜70%) in forms similar to HgS). Different levels of S(0) addition increased the MeHg accumulation in rice. After a sequential extraction analysis of the chemical forms of Hg in the rhizosphere, the results showed that S(0) addition increased the organic bound Hg and decreased the residual Hg in the soils. An Hg LIII XANES further showed that S(0) addition increased the proportion of Hg in the form of RS-Hg-SR and decreased the proportion of Hg in the form of HgS, indicating that S(0) input may reactivate the non-bioavailable Hg in the rhizosphere and improve the net Hg methylation. These findings suggest that the application of S fertilizers to Hg-contaminated paddy soils may increase the MeHg concentration in the edible parts of crops, which may lead to more potential health problems in humans depending on the crop type. However, our study also suggests that S(0) addition could be an effective measure for mobilizing the insoluble Hg and accelerating the phytoremediation process in Hg-contaminated paddy soils.


Assuntos
Bioacumulação , Fertilizantes , Compostos de Metilmercúrio/análise , Mineração , Oryza/metabolismo , Poluentes do Solo/análise , Enxofre/química , Biomassa , China , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Compostos de Metilmercúrio/metabolismo , Oryza/crescimento & desenvolvimento , Rizosfera , Solo/química , Poluentes do Solo/metabolismo
18.
Sci Total Environ ; 637-638: 971-979, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29763878

RESUMO

The influence of three Ca-containing amendments (dolomite, slaked lime, and limestone) on soil water soluble Pb (Pb-w) levels, Pb accumulation by two rice plants (TJ-8, japonica and II-3301, indica), and the factors affecting Pb-w were investigated. Pot experiment was performed under waterlogged conditions using Pb-contaminated soil collected from an agricultural field near a mine. It was found that the soil amendments significantly reduced Pb content in the rice plants in the order dolomite > slaked lime > limestone, irrespective of rice cultivar. The Pb content of brown rice with the added soil amendments was lower than that of the recommended limit (0.2 mg kg-1, GB2762-2017) except for cultivar II-3301 with slaked lime. There was a significant positive correlation between the Pb content of the roots, stems, leaves, and grains and the soil Pb-w levels. The amendments reduced soil Eh, Fe, and Mn concentrations in the pore water and increased soil pH. The total organic carbon (TOC) in the pore water significantly decreased for II-3301 but not for TJ-8 at the ripening stage after addition of the amendments. Among soil Eh, pH, TOC, Fe, and Mn in the pore water, Fe and Mn were the most influential in lowering soil Pb-w levels. The amendments inhibited the formation of iron plaques on the root surface and reduced Pb adsorption. The Pb content of the roots was positively correlated with that in iron plaque. These findings are significant as they imply that the application of Ca-containing amendments in Pb-contaminated paddy soils near mines is an effective approach for in situ immobilization of Pb and reduction in Pb levels in the edible parts of crops.


Assuntos
Chumbo/metabolismo , Oryza/fisiologia , Poluentes do Solo/metabolismo , Agricultura/métodos , Cálcio/metabolismo , Poluição Ambiental , Fertilizantes , Chumbo/análise , Solo , Poluentes do Solo/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA