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1.
Artigo em Inglês | MEDLINE | ID: mdl-38946103

RESUMO

In this research, a novel MgSiO3 fiber membrane (MSFM) loaded with indocyanine green (ICG) and doxorubicin (DOX) was prepared. Because of MgSiO3's unique lamellar structure composed of a silicon-oxygen tetrahedron, magnesium ion (Mg2+) moves easily and can be further replaced with other cations. Therefore, because of the positively charged functional group of ICG, MSFM has a rather high drug loading for ICG. In addition, there is electrostatic attraction between DOX (a cationic drug) and ICG (an anionic drug). Hence, after loading ICG, more DOX can be adsorbed into MSFM because of electrostatic interaction. The ICG endows the MSFM outstanding photothermal therapy (PTT) performance, and DOX as a chemotherapeutic drug can restrain tumor growth. On the one hand, H+ exchanged with the positively charged DOX based on the MgSiO3 special lamellar structure. On the other hand, the thermal effect could break the electrostatic interaction between ICG and DOX. Based on the above two points, both tumor acidic microenvironment and photothermal effect can trigger DOX release. What's more, in vitro and in vivo antiosteosarcoma therapy evaluations displayed a superior synergetic PTT-chemotherapy anticancer treatment and excellent biocompatibility of DOX&ICG-MSFM. Finally, the MSFM was proven to greatly promote cell proliferation, differentiation, and bone regeneration performance in vitro and in vivo. Therefore, MSFM provides a creative perspective in the design of multifunctional scaffolds and shows promising applications in controlled drug delivery, antitumor performance, and osteogenesis.

2.
Langmuir ; 40(20): 10804-10813, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38723143

RESUMO

Efficiently regulating the rebound behavior of droplets post-impact is crucial for various fields, mainly including the development of self-cleaning applications, the design of surface functional materials, and the advancement of industrial techniques. By performing molecular dynamics simulations, we investigated the impact and jumping behavior of droplets on heterogeneous substrates with different wetting regions. We found that, during the impacting evolution process, the retracted droplets would move toward regions with stronger wettability due to the unbalanced force caused by the wettability difference, revealing the directional migration ability. The values of the wettability difference strongly affect the degree of oblique rebound and contact time when droplets can jump off the substrate. We then designed the surfaces with a wettability gradient and found that the oblique rebound angle could be well controlled and the contact time further reduced. Our findings may provide valuable insight into the relationship between the wettability gradient and the behavior of liquid droplets on surfaces, with broad implications for various fields such as surface engineering, materials science, microfluidics, etc.

3.
ACS Omega ; 8(8): 7602-7606, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36872959

RESUMO

The presented study evaluated the effect of cosubstitution of larger and smaller divalent cations on the thermally induced crystallization of amorphous calcium phosphate (ACP). The predesigned combinations of larger (Sr2+ and Ba2+) and smaller (Mg2+, Cu2+, and Co2+) divalent cations were carried out and their effects on the thermodynamic equilibrium between α/ß-tricalcium phosphate (TCP) were outlined. The coexistence of larger and smaller divalent cations shielded the formation of α-TCP and shifted the thermodynamic equilibrium toward the ß-TCP, which implied that the smaller cations dominated the crystalline phase. However, the retarded crystallization induced by the larger cations still remained and allowed ACP to maintain its amorphous nature partly or completely until a higher temperature.

4.
Front Psychiatry ; 13: 976159, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276313

RESUMO

Background: Research is increasingly identifying an overlap between psychosis and immunological dysregulation. Certain autoantibodies are being identified in a small but probably relevant subgroup of patients with psychosis. The term "autoimmune psychosis" (AIP) and its corresponding red-flag signs present the opportunity for a new field in psychiatry to promote diagnostic workup and immunomodulating therapy in individual cases. Objectives: The present protocol aims to determine the seroprevalence of autoantibodies in first-episode psychosis (FEPs) using AIP red flag signs, and to explore the frequency of autoantibody subtypes and potential mediating confounders. Methods/design: This is a hospital-based case-control study. All participants will be consecutively selected from the main tertiary psychiatric hospital in Shenzhen City, China. Individuals admitted to the psychiatric ward and diagnosed with FEPs will be enrolled. Based on recent consensus, participants with red flags of AIPs will be defined as cases, while the remainder will be matched as controls. Seropositive antibodies will be detected and verified in cerebrospinal fluid (CSF) samples based on the fixed cell-based assay (CBA) method. The propensity score-adjusted odds ratios will be determined to investigate the key mediating confounders regarding autoantibody subtypes and red flag subsets. Discussion: The results of this study will facilitate the early identification of AIPs in FEP patients using the red flag sign and help identify key mediators that improve the accuracy of diagnostic algorithms. It will have clinical significance to focus on serum antibodies that have been verified in CSF samples, due to its consistency with clinical practices in current psychiatry.

5.
Materials (Basel) ; 15(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35629690

RESUMO

Silica is one of the most widely used ceramics due to its excellent chemical stability and dielectric property. However, its destructive brittle nature inhabits it from wider application as a functional ceramic. An improvement in toughness is a challenging topic for silica ceramic, as well as other ceramics. In the paper, silica ceramic with different types of boron nitride powders and alumina platelets was fabricated by hot-pressing. Introduction of the additives had great influence on the composites' mechanical properties and microstructure. The silica matrix composite containing micro-sized boron nitride powders possessed the best mechanical properties, including the bending strength (134.5 MPa) and the fracture toughness (1.85 Mpa·m1/2). Meanwhile, the introduction of alumina platelets combined with boron nitride nanosheets achieved an effective enhancement of fracture toughness while maintaining the bending strength. Compared with the monolithic silica, the composite with simultaneous addition of alumina platelets and boron nitride nanosheets had a fracture toughness of 2.23 Mpa·m1/2, increased by approximately 27% (1.75 Mpa·m1/2). The crack deflection and platelet pullout were contributing to enhancement of the fracture toughness. The improved mechanical properties, combined with the intrinsic excellent dielectric and chemical properties, make the silica matrix composites promising wave transparent and thermal protection materials.

6.
Materials (Basel) ; 15(8)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35454649

RESUMO

Alumina is one of the most commonly used and researched structural ceramic because of its excellent properties. However, its intrinsic brittleness is the fatal drawback, which hinders it from wider applications. How to improve its fracture toughness as well as the bending strength is always challenging for material researchers. In this paper, alumina matrix composites were fabricated by hot-pressing, in which some additives, including zirconia, alumina platelets, and MXene, were incorporated. The influence of the introduced additives on their microstructure and mechanical properties was investigated. Compare with the monolithic alumina, both bending strength and fracture toughness of all samples were improved greatly. Incorporation of zirconia was beneficial to the mechanical properties due to the phase-transformation strengthening and toughening mechanism. While alumina platelets resulted in high fracture toughness because of the self-toughening of elongated grains. The synergistic effect of alumina platelets and MXene enormously improved the fracture toughness from 2.9 ± 0.3 MPa·m1/2 for monolithic alumina to 7.5 ± 0.4 MPa·m1/2 for the composite, which was increased by 159%. This work will provide useful references for the fabrication of high-strength and high-toughness alumina ceramics by introducing additives properly.

7.
J Biomater Appl ; 36(9): 1712-1719, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35108128

RESUMO

Biphasic calcium phosphate (BCP) is an important research field based on calcium phosphate biomaterials. In this paper, a new synthesis method of CDHA/α-TCP BCP was studied. By controlling the addition amount of citric acid, the relative contents of CDHA and α-TCP in the BCP were controlled. BCP bone cement was prepared with different proportions of BCP as raw materials. The BCP bone cement was characterized by XRD and SEM, and evaluated by measuring setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that the increase of CDHA content can lead to the reduction of the setting time of bone cement and delay the degradation rate of BCP bone cement.


Assuntos
Cimentos Ósseos , Durapatita , Cálcio , Fosfatos de Cálcio , Hidroxiapatitas
8.
Oncol Rep ; 46(3)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34328200

RESUMO

Tumor microenvironment (TME) can serve as the 'soil' for the growth and survival of tumor cells and function synergically with tumor cells to mediate tumor progression and therapeutic resistance. Reactive oxygen species (ROS) is somewhat of a double­edged sword for tumors. Accumulating evidence has reported that regulating ROS levels can serve an anti­tumor role in the TME, including the promotion of cancer cell apoptosis, inhibition of angiogenesis, preventing immune escape, manipulating tumor metabolic reorganization and improving drug resistance. In the present review, the potential role of ROS in anti­tumor therapy was summarized, including the possibility of directly or indirectly targeting the TME.


Assuntos
Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral , Humanos
9.
J Appl Biomater Funct Mater ; 19: 2280800021996999, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33653180

RESUMO

Strontium has been widely used in bone repair materials due to its roles in promoting osteoclast apoptosis and enhancing osteoblast proliferation. In this work, synthesis and the effects of Sr2+ doping α-tricalcium phosphate at low-temperature was studied. The setting time and the mechanical properties of α-tricalcium phosphate were controlled by varying the content of Sr2+. The synthesized compounds were evaluated by XRD, SEM, XPS, setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that Sr2+ can improve the compressive strength and cell activity of calcium phosphate bone cement.


Assuntos
Dopagem Esportivo , Cimentos Ósseos , Fosfatos de Cálcio , Força Compressiva , Teste de Materiais , Estrôncio , Temperatura
10.
Asia Pac Psychiatry ; 13(2): e12446, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33327044

RESUMO

INTRODUCTION: The objective of this study was to explore the gender differences of community-dwelling patients with schizophrenia in terms of socio-demographics, clinical characteristic and quality of life (QOL). METHODS: A total of 433 community-dwelling patients with schizophrenia were recruited in Shenzhen city, China. Data were obtained from a face-to-face interview with standard research questionnaire. The QOL and insight were assessed using the WHOQOL-BREF and the Chinese version of the insight and treatment attitude questionnaire, respectively. RESULTS: This cross-sectional study included 206 male and 227 female patients. Male patients were more likely to be educated, employed, smoking cigarettes and drinking alcohol, and have an early age of illness onset. In contrast, female patients were more likely to be married/cohabitating and have drug side effects. There was no significant difference between genders across all QOL domain. Multiple regression analyzes showed that mental symptoms were negatively associated with all QOL domains, whereas frequency of exercise in the past year was positively associated with all QOL domains. Higher education levels, household per capita annual income in past year (≥100 000 RMB), employment status, IATQ score, drug side effects, marital status, and number of hospitalization were also significantly associated with specific QOL domains. DISCUSSION: There was significant gender difference in socio-demographics and clinical characteristics among community schizophrenia patients in Shenzhen city. Gender-specific intervention measures are needed to improve the functioning and QOL in patients with schizophrenia.


Assuntos
Qualidade de Vida , Esquizofrenia , Estudos Transversais , Feminino , Humanos , Masculino , Esquizofrenia/epidemiologia , Fatores Sexuais , Inquéritos e Questionários
11.
J Recept Signal Transduct Res ; 41(6): 593-603, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33108937

RESUMO

C-X-C motif chemokine ligand 14 (CXCL14) has antitumor effect. Kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway is activated in various tumors. The relationship between CXCL14 and Akt/mTOR pathway in hepatocellular carcinoma (HCC) remained elusive. Therefore, this paper aimed to examine their interaction in HCC. First, CXCL14 expression was determined to be low-expressed in HCC tissues and cells (SNU-423, SNU-182, SNU-387, PLC/PRF/5, HuH7, and HCCLM3). Then, CXCL14 was overexpressed in HuH7 cells and inhibited in HCCLM3 cells to help investigate the function of CXCL14 on cell viability, growth and apoptosis. Akt activator (SC79) and inhibitor (AZD5363) were used to examine the involvement of Akt pathway in hepatocellular carcinoma. Overexpressed CXCL14 suppressed cell viability and growth, but promoted the apoptosis by upregulated Bax and cleaved(C) caspase-3, donwregulated Bcl-2 and the inhibition of Akt and mTOR phosphorylation. Meanwhile, knockdown of CXCL14 imposed an opposite effect to overexpressed CXCL14. SC79 partially mitigated the functions of overexpressed CXCL14, while AZD5363 mitigated the functions of CXCL14 knockdown. To conclude, CXCL14 inhibited growth but promoted apoptosis of HCC cells via suppressing Akt/mTOR pathway, thus, CXCL14 might be a potential target for HCC treatment in clinical practice.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Quimiocinas CXC/metabolismo , Regulação Neoplásica da Expressão Gênica , Fosfatidilinositol 3-Quinases/química , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Quimiocinas CXC/genética , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Células Tumorais Cultivadas
12.
J Nanosci Nanotechnol ; 20(10): 6441-6449, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32384996

RESUMO

As an Mn+1AXn phase ternary layered carbide, Ti3SiC2 possesses the advantages of both excellent stability and high electrical conductivity, which are considered to be promising electrode materials for supercapacitors. Ti3SiC2/Carbon nanofiber composites with one-dimensional nanostructures were successfully synthesized via electrospinning. Systematic electrochemical tests showed that the Ti3SiC2/Carbon composite possesses a large specific capacitance of 133.1 F/g at the current density of 1 A/g, high rate capability of 113.7% capacitance retention from 1 to 10 A/g, and low resistance of 1.07 Ω. After assembling the asymmetrical supercapacitor, Ti3SiC2/Carbon provides the energy density of 7.02 Wh/kg at the power density of 140 W/kg. In addition, Ti3SiC2/Carbon composite is highly stable, with 74.6% capacity retention after 4000 cycles. Ti3SiC2/Carbon's superior electrochemical properties are ascribed to the 1D nanowire structure and the high specific surface area. Ti3SiC2/Carbon is a prospective electrode material for future supercapacitors.

13.
BMC Cancer ; 19(1): 1063, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703647

RESUMO

BACKGROUND: Prostate cancer is one of the most common cancers in the world. The results of treatment after hypofractionated radiotherapy only have been reported from several small randomized clinical trials. Therefore, we conducted a meta-analysis to compare clinical outcomes of hypofractionated radiotherapy versus conventional radiotherapy in the treatment of intermediate- to high-risk localized prostate cancer. METHODS: Relevant studies were identified through searching related databases till August 2018. Hazard ratio (HR) or risk ratio (RR) with its corresponding 95% confidence interval (CI) was used as pooled statistics for all analyses. RESULTS: The meta-analysis results showed that overall survival (HR = 1.12, 95% CI: 0.93-1.35, p = 0.219) and prostate cancer-specific survival (HR = 1.29, 95% CI: 0.42-3.95, p = 0.661) were similar in two groups. The pooled data showed that biochemical failure was RR = 0.90, 95% CI: 0.76-1.07, p = 0.248. The incidence of acute adverse gastrointestinal events (grade ≥ 2) was higher in the hypofractionated radiotherapy (RR = 1.70, 95% CI: 1.12-2.56, p = 0.012); conversely, for late grade ≥ 2 gastrointestinal adverse events, a significant increase in the conventional radiotherapy was found (RR = 0.75, 95% CI: 0.61-0.91, p = 0.003). Acute (RR = 1.01, 95% CI: 0.89-1.15, p = 0.894) and late (RR = 0.98, 95% CI: 0.86-1.10, p = 0.692) genitourinary adverse events (grade ≥ 2) were similar for both treatment groups. CONCLUSION: Results suggest that the efficacy and risk for adverse events are comparable for hypofractionated radiotherapy and conventional radiotherapy in the treatment of intermediate- to high-risk localized prostate cancer.


Assuntos
Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Hipofracionamento da Dose de Radiação , Ensaios Clínicos Controlados Aleatórios como Assunto , Trato Gastrointestinal/efeitos da radiação , Humanos , Masculino , Neoplasias da Próstata/etnologia , Lesões por Radiação/etiologia , Taxa de Sobrevida , Resultado do Tratamento , Sistema Urogenital/efeitos da radiação , População Branca
14.
J Mater Sci Mater Med ; 30(3): 37, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30840152

RESUMO

In this work, the setting process of reduced graphene (RGO)/carbon nanotubes (CNTs) reinforced calcium phosphate cement (CPC) were conducted in a microwave environment. The introduction of microwave can increase the reaction temperature, speed up the vibration of water molecules and eliminate bubbles from the interface between RGO, CNTs and the substrate. Comparing with CPC without microwave treatment, the final setting time of composites after microwave treatment are almost a half, the flexural strength and the compressive strength are increased by 19.86% and 21.68% respectively, which are 17.38 MPa and 104.52 MPa. Meanwhile, the CPC composites remain the excellent bioactivity.


Assuntos
Cimentos Ósseos/química , Fosfatos de Cálcio/química , Grafite/química , Nanotubos de Carbono/química , Osso e Ossos/patologia , Força Compressiva , Humanos , Inflamação , Teste de Materiais , Microscopia Eletrônica de Varredura , Micro-Ondas , Pressão , Estresse Mecânico , Temperatura
15.
J Inflamm (Lond) ; 15: 14, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30038551

RESUMO

BACKGROUND: Articular cartilage diseases are considered a major health problem, and tissue engineering using human mesenchymal stem cells (MSCs) have been shown as a promising solution for cartilage tissue repair. Hesperidin is a flavonoid extract from citrus fruits with anti-inflammatory properties. We aimed to investigate the effect of hesperidin on MSCs for cartilage tissue repair. MSCs were treated by hesperidin, and colony formation and proliferation assays were performed to evaluate self-renewal ability of MSCs. Alcian blue staining and Sox9 expression were measured to evaluate chondrogenesis of MSCs. Secretion of pro-inflammatory cytokines IFN-γ, IL-2, IL-4 and IL-10, and expression of nuclear factor kappa B (NF-κB) subunit p65 were also assessed. RESULTS: Hesperidin improved self-renewal ability and chondrogenesis of MSCs, inhibited secretion of pro-inflammatory cytokines IFN-γ, IL-2, IL-4 and IL-10, and suppressed the expression of p65. Overexpression of p65 was able to reverse the hesperidin inhibited secretions of pro-inflammatory cytokines, and abolish the enhancing effect of hesperidin on chondrogenesis of MSCs. CONCLUSION: Hesperidin could serve as a therapeutic agent to effectively enhance chondrogenesis of human MSCs by inhibiting inflammation to facilitate cartilage tissue repair.

16.
Cell Prolif ; 49(5): 636-43, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27554041

RESUMO

OBJECTIVES: Emerging studies have demonstrated that microRNAs (miRNAs) play crucial roles in carcinogenesis of many developing human tumours. However, the functions and mechanisms of miR-297 in lung cancer have, up to now, been largely undefined. MATERIALS AND METHODS: Here, miR-297 expression was measured in lung adenocarcinoma tissues and cell lines, using qRT-PCR. Lung adenocarcinoma cell line was treated with an miR-297 mimic. MTT and colony analysis were performed to detect cell proliferation and colony formation. The direct target gene of miR-297 was assessed by qRT-PCR, Western blotting and luciferase assays. RESULTS: We demonstrated that miR-297 expression was upregulated in lung adenocarcinomas compared to adjacent normal tissues. Expression of miR-297 was also upregulated in tested lung adenocarcinoma cell lines. Ectopic expression of miR-297 enhanced lung adenocarcinoma cell proliferation and colony formation. Furthermore, overexpression of miR-297 promoted cell migration and invasion. In addition, we identified Glypican-5 (GPC5) as a direct target gene of miR-297 in lung adenocarcinoma cells. Expression of GPC5 was downregulated in both lung adenocarcinoma tissues and cell lines. Moreover, expression of GPC5 was inversely associated with expression of miR-297 in lung adenocarcinoma tissues. CONCLUSIONS: These results suggest that miR-297 acted as an oncogenic miRNA, partly by targeting GPC5, adenocarcinoma of the lung.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , Glipicanas/genética , Neoplasias Pulmonares/genética , Pulmão/patologia , MicroRNAs/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/patologia , Oncogenes , Regulação para Cima
17.
PLoS One ; 9(4): e91895, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24705393

RESUMO

BACKGROUND: The aim of this study was to test the ability of the Chinese version of the Mood Disorder Questionnaire (MDQ) to identify Bipolar Disorders (BD) in patients diagnosed with Major Depressive Disorder (MDD) or Unipolar Disorder (UD) in the clinical setting. METHODS: 1,487 being treated for MDD or UD at 12 mental health centers across China, completed the MDQ and subsequently examined by the Mini International Neuropsychiatric Interview (MINI). Receiver Operating Characteristic(ROC) curves were used to determine the ability of the MDQ to differentiate between BD (BD, BD-I and BD-II) and MDD or UD and patients with BD-I from patients with BD-II. RESULTS: Of the 1,487 patients, 309 (20.8%) satisfied the DSM-IV criteria for BD: 118 (7.9%) for BD-I and 191 (12.8%) for BD-II. When only part one of the MDQ was used, the best cutoff was 7 between BD and UD (sensitivity 0.66, specificity 0.88, positive predictive value 0.59, negative predictive value 0.91), 6 between BD-II and UD, and 10 between BD-I and BD-II. If all three parts of the MDQ were used, the MDQ could not distinguish between BD and UD at a cutoff of 7 (or 6), and the sensitivity was only 0.22 (or 0.24). CONCLUSION: The Chinese version of the MDQ had good psychometric features in screening bipolar disorders from depressive patients with mood disorders when part two and part three of the MDQ were ignored.


Assuntos
Transtorno Bipolar/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Transtornos do Humor/diagnóstico , Psicometria/métodos , Inquéritos e Questionários , Adulto , Transtorno Bipolar/epidemiologia , China/epidemiologia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/epidemiologia , Feminino , Humanos , Masculino , Transtornos do Humor/complicações , Transtornos do Humor/epidemiologia , Escalas de Graduação Psiquiátrica , Sensibilidade e Especificidade
18.
Mar Pollut Bull ; 76(1-2): 420-6, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24060473

RESUMO

Selected heavy metals (Cr, Cu, Ni, Pb and Zn) in surface sediments from the coastal Shandong Peninsula (Yellow Sea) have been determined to evaluate the spatial distribution and potential ecological risk. Results showed that heavy metal concentrations in the sediments generally met the criteria of China Marine Sediment Quality. However, both the enrichment factor (EF) and geoaccumulation index (Igeo) values suggested the elevation of Pb concentration in the region. Based on the effect-range classification (TEL-PEL SQGs), Cr, Cu and Ni were likely to pose environment risks. Spatial distribution of ecotoxicological index (mean-PEL-quotient) suggested that most of the surface sediments have a 21% probability of being toxic. Similar results were also obtained by pollution load index (PLI). The spatial distribution pattern of heavy metal in surface sediments is a basis for undertaking appropriate action to protect marine sediment quality.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , China , Poluição Química da Água/estatística & dados numéricos
19.
Environ Sci Pollut Res Int ; 20(6): 4099-110, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23224582

RESUMO

The concentrations of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) and organic carbon in surface sediments, collected from the southern Bohai Bay, were determined to assess the potential contamination and determine the environmental risks associated with heavy metals. Results showed that heavy metal concentrations in the sediments generally met the China Marine Sediment Quality criteria. Both the ecotoxicological index and the potential ecological risk index suggest that the combined ecological risk of the six studied metals may be low, with the highest ecotoxicological potential zones located in the offshore area. The methods of enrichment factor and geoaccumulation index suggested that elevated concentrations of Cd, Cr, and Ni are presented in the region. Multivariate analysis also indicated that the lithogenic factor dominates the distribution of most part of the considered metals in the study area, whereas Cd and Cr are clearly influenced by anthropogenic inputs. The results of this study are likely to be a useful tool to authorities in charge of sustainable marine management.


Assuntos
Baías/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , China , Análise por Conglomerados , Ecotoxicologia , Guias como Assunto , Análise Multivariada , Análise de Componente Principal , Medição de Risco
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