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1.
J Virol ; 97(3): e0197722, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36815839

RESUMEN

African swine fever (ASF) is an acute and severe infectious disease caused by the ASF virus (ASFV). The mortality rate of ASF in pigs can reach 100%, causing huge economic losses to the pig industry. Here, we found that ASFV protein MGF505-7R inhibited the beta interferon (IFN-ß)-mediated Janus-activated kinase-signal transducer and activation of transcription (JAK-STAT) signaling. Our results demonstrate that MGF505-7R inhibited interferon-stimulated gene factor 3 (ISGF3)-mediated IFN-stimulated response element (ISRE) promoter activity. Importantly, we observed that MGF505-7R inhibits ISGF3 heterotrimer formation by interacting with interferon regulatory factor 9 (IRF9) and inhibits the nuclear translocation of ISGF3. Moreover, to demonstrate the role of MGF505-7R in IFN-I signal transduction during ASFV infection, we constructed and evaluated ASFV-ΔMGF505-7R recombinant viruses. ASFV-ΔMGF505-7R restored STAT2 and STAT1 phosphorylation, alleviated the inhibition of ISGF3 nuclear translocation, and showed increased susceptibility to IFN-ß, unlike the parental GZ201801 strain. In conclusion, our study shows that ASFV protein MGF505-7R plays a key role in evading IFN-I-mediated innate immunity, revealing a new mode of evasion for ASFV. IMPORTANCE ASF, caused by ASFV, is currently prevalent in Eurasia, with mortality rates reaching 100% in pigs. At present, there are no safe or effective vaccines against ASFV. In this study, we found that the ASFV protein MGF505-7R hinders IFN-ß signaling by interacting with IRF9 and inhibiting the formation of ISGF3 heterotrimers. Of note, we demonstrated that MGF505-7R plays a role in the immune evasion of ASFV in infected hosts and that recombinant viruses alleviated the effect on type I IFN (IFN-I) signaling and exhibited increased susceptibility to IFN-ß. This study provides a theoretical basis for developing vaccines against ASFV using strains with MGF505-7R gene deletions.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Interferón Tipo I , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón , Replicación Viral , Animales , Fiebre Porcina Africana/inmunología , Fiebre Porcina Africana/virología , Virus de la Fiebre Porcina Africana/genética , Virus de la Fiebre Porcina Africana/inmunología , Inmunidad Innata , Interferón Tipo I/inmunología , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/inmunología , Transducción de Señal , Porcinos , Proteínas Virales/genética , Proteínas Virales/inmunología , Replicación Viral/fisiología , Transporte Activo de Núcleo Celular/genética , Evasión Inmune/genética
2.
Int J Hyperthermia ; 41(1): 2335201, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38583875

RESUMEN

PURPOSE: Radiotherapy (RT) is the primary treatment for prostate cancer (PCa); however, the emergence of castration-resistant prostate cancer (CRPC) often leads to treatment failure and cancer-related deaths. In this study, we aimed to explore the use of microwave hyperthermia (MW-HT) to sensitize PCa to RT and investigate the underlying molecular mechanisms. METHODS: We developed a dedicated MW-HT heating setup, created an in vitro and in vivo MW-HT + RT treatment model for CRPC. We evaluated PC3 cell proliferation using CCK-8, colony experiments, DAPI staining, comet assay and ROS detection method. We also monitored nude mouse models of PCa during treatment, measured tumor weight, and calculated the tumor inhibition rate. Western blotting was used to detect DNA damage repair protein expression in PC3 cells and transplanted tumors. RESULTS: Compared to control, PC3 cell survival and clone formation rates decreased in RT + MW-HT group, demonstrating significant increase in apoptosis, ROS levels, and DNA damage. Lower tumor volumes and weights were observed in treatment groups. Ki-67 expression level was reduced in all treatment groups, with significant decrease in RT + MW-HT groups. The most significant apoptosis induction was confirmed in RT + MW-HT group by TUNEL staining. Protein expression levels of DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways significantly decreased in RT + MW-HT groups. CONCLUSION: MW-HT + RT treatment significantly inhibited DNA damage repair by downregulating DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways, leading to increased ROS levels, aggravate DNA damage, apoptosis, and necrosis in PC3 cells, a well-established model of CRPC.


Asunto(s)
Adenocarcinoma , Hipertermia Inducida , Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Humanos , Masculino , Animales , Ratones , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Células PC-3 , Especies Reactivas de Oxígeno/metabolismo , Microondas , Proteína p53 Supresora de Tumor/metabolismo , Hipertermia Inducida/métodos , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/metabolismo , Reparación del ADN , Apoptosis , Estrés Oxidativo , Hipertermia , Adenocarcinoma/radioterapia , ADN/metabolismo , Línea Celular Tumoral , Proliferación Celular
3.
Environ Res ; 237(Pt 1): 116997, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37634689

RESUMEN

This work examined the performance and microbial traits in a thermophilic anaerobic digestion (TAD) of waste activated sludge that was impacted by micron zero valent iron (mZVI). Results showed that methane production was promoted by 0.8, 11.9, and 12.0 times, respectively, when mZVI was at dosages of 25, 100, and 250 mg/g total solid (TS). Also, the consumption of volatile fatty acids was increased by mZVI at higher dosages (100 and 250 mg/g TS). Furthermore, 16S rRNA sequencing demonstrated that microbial community stabilized after day 18 regardless of the dosage of mZVI, and that different dosages of mZVI induced different shifts in the functional community of the archaea rather than the bacteria involved in TAD. As a result, mZVI at 100 mg/g TS could increase the relative abundance of archaeal genera Methanothermobacter the most, increasing by 22.8% at the end of TAD compared to CK. Besides, redundancy analysis revealed that the physicochemical properties explained 79.65% and 89.10% of the variations of bacterial and archaeal abundance, respectively. Also, the findings of the correlation analysis revealed that total dissolved iron, ferrous iron, pH, and ammonium nitrogen, may be the key divers of altering functional communities, particularly archaea. Moreover, mZVI at 100 and 250 mg/g TS boosted the metabolic pathways of environmental information processing (ABC transporters) in bacteria and carbon metabolism and methane metabolism for archaea, as well as relative abundances of enzymes and their activities involved in various methanogenic pathways. This study provides new perspectives on the application of mZVI in solid wastes treatments.

4.
Hell J Nucl Med ; 26(2): 157-159, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37527053

RESUMEN

Technetium-99m (99mTc)-pertechnetate can be taken up by both gastric mucosa and thyroid tissue. Ectopic gastric mucosa of upper esophagus found in thyroid scintigraphy is rare. We reported a 31-year-old woman who underwent 99mTc-pertechnetate thyroid static scintigraphy for abnormal ultrasound findings. A focal uptake lesion was found in her upper chest. Single photon emission computed tomography/computed tomography (SPECT/CT) imaging showed increased uptake in multiple sites of the upper esophagus without significant thickening. Eventually, gastroscopic findings revealed multiple ectopic gastric mucosa of upper esophagus.


Asunto(s)
Pertecnetato de Sodio Tc 99m , Glándula Tiroides , Humanos , Femenino , Adulto , Glándula Tiroides/diagnóstico por imagen , Tecnecio , Mucosa Gástrica/diagnóstico por imagen , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Esófago/diagnóstico por imagen , Radiofármacos
5.
Mater Today Bio ; 24: 100878, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38188645

RESUMEN

Excessive bleeding is associated with a high mortality risk. In this study, citric acid and ascorbic acid were sequentially modified on the surface of microcrystalline cellulose (MCAA) to increase its carboxyl content, and their potential as hemostatic materials was investigated. The MCAA exhibited a carboxylic group content of 9.52 %, higher than that of citric acid grafted microcrystalline cellulose (MCA) at 4.6 %. Carboxyl functionalization of microcrystalline cellulose surfaces not only plays a fundamental role in the structure of composite materials but also aids in the absorption of plasma and stimulation of platelets. Fourier -transform infrared (FT-IR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) spectra confirmed that carboxyl groups were successfully introduced onto the cellulose surface. Physical properties tests indicated that the MCAA possessed higher thermal stability (Tmax = 472.2 °C) compared to microcrystalline cellulose (MCC). Additionally, in vitro hemocompatibility, cytotoxicity and hemostatic property results demonstrated that MCAA displayed good biocompatibility (hemolysis ratio <1 %), optimal cell compatibility (cell viability exceeded 100 % after 72 h incubation), and impressive hemostatic effect (BCIMCAA = 31.3 %). Based on these findings, the hemostatic effect of covering a wound with MCAA was assessed, revealing enhanced hemostatic properties using MCAA in tail-amputation and liver-injury hemorrhage models. Furthermore, exploration into hemostatic mechanisms revealed that MCAA can significantly accelerate coagulation through rapid platelet aggregation and activation of the clotting cascade. Notably, MCAA showed remarkable biocompatibility and induced minimal skin irritation. In conclusion, the results affirmed that MCAA is a safe and potentially effective hemostatic agent for hemorrhage control.

6.
Food Chem ; 423: 136305, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37178597

RESUMEN

Huajiao is a highly valued spice that is susceptible to fraudulent adulteration, particularly the addition of edible oils to increase weight and improve color. Nuclear magnetic resonance (1H NMR) and chemometrics were used to analyze 120 huajiao samples adulterated with different types and levels of edible oils. Using untargeted data and partial least squares-discriminant analysis (PLS-DA), the discrimination rate between types of adulteration reached 100% accuracy, and the R2 value of the prediction set for the level of adulteration using the targeted analysis dataset combined with PLS-regression methods reached 0.99. Triacylglycerols, major components of edible oils, were identified as a marker of adulteration through the variable importance in projection of the PLS-regression. A quantitative method based on the sn-3 triacylglycerol signal was developed that can achieve a detection limit of 0.11%. Testing of 28 market samples showed adulteration with various edible oils, with adulteration rates ranging from 0.96% to 4.41%.


Asunto(s)
Zanthoxylum , Espectroscopía de Protones por Resonancia Magnética , Quimiometría , Aceites de Plantas/análisis , Espectroscopía de Resonancia Magnética , Contaminación de Alimentos/análisis
7.
Virol Sin ; 36(5): 1124-1132, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33974230

RESUMEN

No avian H7N9 outbreaks have occurred since the introduction of H7N9 inactivated vaccine in the fall of 2017. However, H7N9 is still prevalent in poultry. To surveil the prevalence, genetic characteristics, and antigenic changes of H7N9, over 7000 oropharyngeal and cloaca swab specimens were collected from live poultry markets and farms in 15 provinces of China from 2017 to 2019. A total of 85 influenza virus subtype H7N9 strains were isolated and 20 representative strains were selected for genetic analysis and antigenicity evaluation. Results indicated the decreased prevalence of low-pathogenic H7N9 strains while highly-pathogenic H7N9 strains became dominated since the introduction of vaccine. Phylogenetic analysis showed that strains from 2019 formed an independent small branch and were genetically distant to strains isolated in 2013-2018. Analysis of key amino acid sites showed that the virus strains may adapt to the host environment evolutionally through mutation. Our analysis predicted additional potential glycosylation sites for HA and NA genes in the 2019 strains. Sequence analysis of HA gene in strains isolated from 2018 to 2019 showed that there were an increased nucleotide substitution rate and an increased mutation rate in the first and second nucleotides of coding codons within the open reading frame. The hemagglutination inhibition (HI) assay showed that H7-Re1 and H7-Re2 exhibited a lower HI titer for isolates from 2019, while H7-Re3 and rLN79 showed a high HI titer. The protective effect of the vaccine decreased after 15 months of use. Overall, under vaccination pressure, the evolution of influenza virus subtype H7N9 has accelerated.


Asunto(s)
Subtipo H7N9 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Aviar , Gripe Humana , Animales , China/epidemiología , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Humanos , Subtipo H7N9 del Virus de la Influenza A/genética , Gripe Humana/prevención & control , Filogenia , Vacunación
8.
Front Microbiol ; 12: 633835, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33746926

RESUMEN

This study aimed to investigate the genetic evolution of the H9N2 avian influenza virus (AIV). Whole genome phylogenetic trees were constructed based on 306 H9N2 avian influenza strains collected in China from 2014 to 2019. The results showed that eight gene sequences were clustered separately according to their dominant clades, and a total of 10 genotypes were identified (seven of which were novel types). Among them, G57 genotype was confirmed as the most prevalent genotype with a frequency of 94%. In China, the G57 genotype of H9N2 first emerged in 2007, and then became the most common genotype in 2013. Therefore, the nucleotide substitution rates of G57 genotype in HA and NA genes collected from 2007 to 2019 were estimated, and the positive selection pressure sites in the same data set were measured. Taking 2013 as the boundary, the time period was divided into two periods: 2007-2012 and 2013-2019. From 2007 to 2012, multiple genotypes coexisted and could bear the pressures from both nature and environment; while G57 genotype was still in the adaptation stage, subjected to less selection pressure and in the process of slow evolution. However, from 2013 to 2019, G57 became the dominant genotype, and most of the external pressure reacted on it. Moreover, G57 genotype showed better adaptability than other genotypes. From 2013 to 2019, the nucleotide substitution rates of the HA gene were increased, and the positive selection pressures on HA and NA genes were stronger compared to those from 2007 to 2012. To sum up, the absolutely dominant G57 genotype exhibited a relatively constant genotype frequency and experienced adaptive evolution and natural selection simultaneously during the monitoring period. Therefore, urgent attention and diligent surveillance of H9N2 avian influenza virus are becoming increasingly important.

9.
Stem Cells Int ; 2020: 7416493, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33014069

RESUMEN

Mesenchymal stem cells (MSCs) are multipotent progenitor cells in adult tissues. The aim of this study is to isolate and identify synovial fluid-derived mesenchymal stromal cells (SF-MSCs) from the popliteal cyst fluid of pediatric patients. SF-MSCs were collected from the popliteal cyst fluid of pediatric patients during cystectomy surgery. After cyst fluid extraction and adherent culturing, in vitro morphology, growth curve, and cell cycle were observed. The expression of stem cell surface markers was analyzed by flow cytometry, and expression of cell marker protein was detected by immunofluorescence. SF-MSCs were cultured in osteogenic, adipogenic, and chondrogenic differentiation medium. The differentiation potential of SF-MSCs was analyzed by alkaline phosphatase (Alizarin Red), Oil Red O, and Alcian blue. Antibody detection of human angiogenesis-related proteins was performed compared with bone marrow mesenchymal stem cells (BM-MSCs). The results show that SF-MSCs from the popliteal cyst fluid of pediatric patients showed a shuttle appearance and logarithmic growth. Flow cytometry analysis revealed that SF-MSCs were negative for hematopoietic lineage markers (CD34, CD45) and positive for MSC markers (CD44, CD73, CD90, and CD105). Interstitial cell marker (vimentin) and myofibroblast-like cell marker alpha-smooth muscle actin (α-SMA) were positive. These cells could differentiate into osteogenic, adipogenic, and chondrogenic lineages, respectively. Several types of human angiogenesis-related proteins were detected in the cell secretory fluid. These results show that we successfully obtained SF-MSCs from the popliteal cyst fluid of pediatric patients, which have the potential to be a valuable source of MSCs.

10.
Infect Genet Evol ; 77: 104064, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31618691

RESUMEN

To understand the evolution of H9N2 avian influenza virus genotype and its molecular evolution rate, we systematically analyzed 72 H9N2 avian influenza virus sequences isolated from Guangdong province from 2014 to 2018. We found three genotypes (G57, G68, and G118) of the H9N2 avian influenza virus, of which G118 is a newly discovered genotype and G57 is the dominant genotype. The internal gene cassette of the G57 genotype H9N2 avian influenza virus is a stable combination that can easily transport internal genes to other novel avian influenza viruses, and the internal gene cassettes of the G68 and G118 are identical to those of G57.In addition, we estimated the nucleotide substitution rate of the HA and NA genes of the H9N2 influenza virus from 2014 to 2018.The nucleotide substitution rate of HA and NA genes showed an upward trend in 2015 and 2016. In the past two years, H9N2 avian influenza virus recombination has produced genotype G68, which disappeared in 2014 for one year. And very coincidentally, in 2015, there was a new genotype G118. We observed that the emergence of new genotypes was accompanied by a slight increase in overall nucleotide substitution rate. Therefore we hypothesize that the emergence of new genotypes could accelerate the molecular evolution rate of genes. Our research shows that the H9N2 avian influenza virus in Guangdong province has been undergoing intense evolution, demonstrating the need to strengthen influenza surveillance in the region.


Asunto(s)
Pollos/virología , Subtipo H9N2 del Virus de la Influenza A/clasificación , Análisis de Secuencia de ARN/métodos , Sustitución de Aminoácidos , Animales , China , Cloaca/virología , Evolución Molecular , Subtipo H9N2 del Virus de la Influenza A/genética , Tasa de Mutación , Orofaringe/virología , Filogenia
11.
Mar Pollut Bull ; 56(6): 1091-103, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18440030

RESUMEN

Concentrations of all studied organic pollutants, except for DDTs, were greatest at sites in Dalian Bay, where surface sediment concentrations of PHCs, PAHs, PCBs and DDTs exceeded the corresponding ERL values. The sum concentration of DDTs was greatest in Haizhou Bay exceeding the related ERM value. In terms of compositions of PAHs and PAEs, the predominant components were the MMW and HMW compounds, DBP and DEHP, respectively. The main degradation product of p,p'-DDT was p,p'-DDD at most sampling sites. The principal sources of PAHs and DDTs involved various pyrolytic processes (i.e., combustion of biomass and vehicle exhaust), and application of technical DDT (in the form of impurity or raw material), and a mixture of technical DDT and technical dicofol. Moreover, the coastal site with greatest potential ecological risk from total PAHs was located in Dalian Bay, while the littoral areas of Dalian Bay, two harbor cities (Yantai-Weihai), Jiaozhou Bay, and Haizhou Bay, had relatively high potential risk from DDTs, especially in Haizhou Bay.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , China , DDT/análisis , Océanos y Mares , Ácidos Ftálicos/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
12.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 20(5): 279-82, 2008 May.
Artículo en Zh | MEDLINE | ID: mdl-18471358

RESUMEN

OBJECTIVE: To prepare an intelligent determination and analysis system for renal glomerular filtration rate(GFRBMAS), and to explore its value in clinical setting. METHODS: GFRBMAS was prepared by programming with VB 6.0 software. GFR of 79 inpatients suffering from the different diseases was determined accurately by using clearance rate of (99)Tc(m)-diethylene triamine pentaacetic acid (DTPA) (Tc-GFR). The serum creatinine (SCr), blood urea nitrogen (BUN), serum uric acid (Uric), serum calcium (Ca) and serum phosphorus (P) were determined with both GFRBMAS and 7170S automatic biochemistry determination apparatus (ititachi), and the result of GFR was compared with that determined by using GFRBMAS and 7170S automatic biochemical determination apparatus. At the same time GFR was determined by using Robert formula (GFRBMAS-GFR, Robert-GFR), and creatinine clearance rate was calculated with Cockcroft/Gault formula (CG-CCr). All the results were compared and analyzed. RESULTS: No significant difference of SCr, BUN, Uric, Ca and P values determined by two methods. Robert-GFR and CG-CCr values were significantly lower than Tc-GFR value in the normal renal function group and the renal insufficiency group (P<0.01) and that of GFRBMAS-GFR was close to that of Tc-GFR and relative analysis showed that the values of GFRBMAS-GFR, Robert-GFR, CG-CCr showed significantly positive correlation with that of Tc-GFR, but negative correlation with values of SCr and BUN (P<0.05 or P<0.01). CONCLUSION: GFRBMAS-GFR, Robert-GFR and CG-CCr could all reflect GFR with accuracy to certain extent and GFRBMAS-GFR can take the place of Tc-GFR in clinical setting.


Asunto(s)
Diagnóstico por Computador , Tasa de Filtración Glomerular , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
13.
Environ Pollut ; 146(2): 470-7, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16950550

RESUMEN

Studies of heavy metals and organic pollutants in different benthic mussel species from Bohai Sea show that concentrations of Cd in mussels commonly exceed national biological quality standards. In addition, a site located in Laizhou Bay exhibits higher average concentrations of As, Hg and Pb with respect to the other sites. Residual levels of petroleum hydrocarbons at several sites in Liaodong Bay also exceed quality guidelines. Contents and compositional characteristics of DDT and its metabolites in mussels suggest the probability of recent inputs and potential ecological risks to the local benthic environment.


Asunto(s)
Bivalvos/química , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Animales , Arsénico/análisis , Cadmio/análisis , China , DDT/análisis , Ecosistema , Monitoreo del Ambiente/métodos , Plomo/análisis , Mercurio/análisis , Océanos y Mares , Petróleo/análisis , Ácidos Ftálicos/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
14.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 15(4): 226-8, 2003 Apr.
Artículo en Zh | MEDLINE | ID: mdl-12857447

RESUMEN

OBJECTIVE: To investigate the relationship between glomerular filtration rate(GFR) and possible involved clinical factors and to offer an basis for building measurement GFR by the calculation method. METHODS: GFR from 46 cases of normal renal function group and 52 cases of renal insufficient group were determined by using clearance of 99mTc-DTPA, serum creatinine(SCr), urea nitrogen, uric, potassium, sodium, calcium and hemoglobin were determined. Simultaneously, heart rate, urine specific gravity, 24 hours urine protein quantum, average artery pressure, weight index and body surface area were determined. Age, isotope dose for determining GFR were recorded. The simple correlation analysis between GFR in every group and the difference primitive diseases and clinical factors mentioned above were performed and the multiple correlation analysis between every clinical factors mentioned above that had significantly correlation between GFR and GFR were performed as well. RESULTS: GFR in normal renal function group, insufficient group and the difference primitive diseases had significantly negative correlation with SCr, while the correlations between GFR and other clinical factors were different. CONCLUSION: SCr is the ideal index for GFR for renal insufficient patients due to different primitive diseases and patients with normal renal function.


Asunto(s)
Tasa de Filtración Glomerular , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/fisiopatología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Niño , Creatinina/sangre , Femenino , Humanos , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Pentetato de Tecnecio Tc 99m/metabolismo , Tomografía Computarizada de Emisión de Fotón Único , Adulto Joven
17.
Huan Jing Ke Xue ; 32(2): 445-51, 2011 Feb.
Artículo en Zh | MEDLINE | ID: mdl-21528566

RESUMEN

Based on the recent monitoring results, the concentration and distribution of persistent toxic substances in the benthic mussels from the coastal areas of Bohai Sea and North Yellow Sea were determined. The results indicated that, at over 36% of the total sampling sites, the tissue concentrations of petroleum hydrocarbons were higher than the Category I value (15 microg/g, wet weight) of the national marine biological quality standards, especially at the sites near Dalian Bay and Xincun in Hebei Province, the tissue concentrations even exceeded the Category III level (80 microg/g, wet weight). Moreover, higher tissue concentration of PHCs (over the Category I level) during recent years remained in the most monitoring sea areas. At minor sites (mariculture zone in Yantai and Laizhou Bay), the tissue concentrations of As and Pb were relatively higher, and the high levels of Cd (above the Category II value of 2000 ng/g, wet weight) and Hg (above the Category II value of 100 ng/g, wet weight) in mussel bodies presented at several sites situated in coastal areas near Dalian Bay and Xincun of Hebei Province. Additionally, at the sampling sites near Liaodong Bay and Shandong Peninsula, the tissue concentration of Hg showed an annual increase during recent years. At all the monitoring sites, the tissue concentrations of PCBs and HCHs were usually low, while as the case of Hg, the tissue concentrations of PCBs and HCHs in Liaodong Bay increased gradually in these years. The new monitoring results indicated that, most sites with DDTs levels in benthic mussels higher than the Category I value (10 ng/g, wet weight) were located in the coastal areas of Hebei Province belonged to Bohai Bay (such as Zhaojiapu and Xincun). The continuous monitoring in these sea areas demonstrated that, in addition to the historical residues, there may be some fresh input sources of DDT nearby. Consequently, in the neighboring sea areas of Dalian Bay and Xincun, the tissue concentrations of PHCs, Cd and Hg were fairly high (all over their Category II values), and these sea areas could be of relatively stronger potential ecological risk. In view of the gradual increases in tissue concentrations (e. g., Hg, PCBs and HCHs) during the recent years, the coastal areas, for example, of Liaodong Bay and Shandong Peninsula should be addressed with sufficient concern.


Asunto(s)
Bivalvos/química , Contaminación de Alimentos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Agua de Mar/análisis , Contaminantes Químicos del Agua/análisis , Animales , Cadmio/análisis , China , DDT/análisis , Océanos y Mares , Bifenilos Policlorados/análisis
18.
Environ Pollut ; 159(10): 2355-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21752501

RESUMEN

Sorption isotherms of BDE-28 and BDE-47 on natural soils with different contents of soil organic matter (SOM) were investigated. Due to low water solubility of BDEs and resulted narrow ranges of aqueous equilibrium concentration, the linear distribution model showed similar and good fitting efficiency to the linear portion of nonlinear Freundlich curve. For the same sample, the linear and nonlinear model fitting sorption coefficients were close. At the statistically significant level of 0.05 or 0.1, significant relationships of total organic carbon fraction (fOC) with the fitting sorption coefficients can be observed. As for BDE-28, the relationships of fOC and SOM fractions with the single point partition coefficients at different aqueous concentrations of BDEs were significant; while for BDE-47, the relationships became less significant or insignificant, especially at higher aqueous concentrations. The findings in this study may facilitate more understanding on transport and fate of studied BDEs in soil systems.


Asunto(s)
Carbono/química , Éteres Difenilos Halogenados/química , Contaminantes del Suelo/química , Suelo/química , Adsorción , Restauración y Remediación Ambiental , Éteres Difenilos Halogenados/análisis , Modelos Químicos , Bifenilos Polibrominados/análisis , Bifenilos Polibrominados/química , Contaminantes del Suelo/análisis
19.
Huan Jing Ke Xue ; 32(3): 749-57, 2011 Mar.
Artículo en Zh | MEDLINE | ID: mdl-21634174

RESUMEN

The sorption kinetics and isotherms of BDE-28 on three natural soils with different soil organic matter fractions (f(oc)) were investigated. The results indicated that a two (fast and slow)-compartment first-order model was more appropriate for describing the sorption kinetic data, compared to a one-compartment first-order model, especially in the initial sorption stage within 25 h. The fast sorption was predominant during the whole sorption process from beginning to the apparent sorption equilibrium; while the contribution of the slow sorption to the total sorption amount gradually increased and then achieved a plateau at 49 h or 55 h. The approaching time to the individual sorption capacity for the fast sorption was much shorter than that for the slow sorption. The contribution of the fast sorption to the increase in the total sorption amount of BDE-28 was prevailing at the beginning of sorption process from 2.5 h to 4.5 h; whereas the fraction of the slow sorption became primary at the subsequent stage of sorption process. The fitting results by the Dubinin-Ashtakhov (DA) model were comparable with those by the Freundlich model in the range of apparent equilibrium concentration studied. As for the Freundlich model, the nonlinear exponent (n) values of BDE-28 for the two samples with lower f(oc) (0.72%) or higher f(oc) (7.90%) approached to 1.0 (1.03 +/- 0.05 and 1.00 +/- 0.05, respectively), suggesting the linear sorption characteristics in the studied range of apparent equilibrium concentrations of BDE-28; while the nonlinear behavior of BDE-28 for the left sample with medium f(oc) (4.42%) was indicated by its n value less than 1.0 (0.89 +/- 0.04).


Asunto(s)
Contaminantes Ambientales/aislamiento & purificación , Bifenilos Polibrominados/aislamiento & purificación , Contaminantes del Suelo/aislamiento & purificación , Suelo/química , Adsorción , Contaminantes Ambientales/metabolismo , Modelos Teóricos , Bifenilos Polibrominados/metabolismo , Contaminantes del Suelo/metabolismo
20.
Environ Pollut ; 158(9): 2815-20, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20609504

RESUMEN

Sorption kinetic characteristics of BDE-28 and BDE-47 on five natural soils with different organic carbon fractions were investigated, and could be satisfactorily described by a two (fast and slow)-compartment first-order model with the ratio of rate constants ranged from 9 to 94 times. The fast compartment made a dominant contribution (71%-94%) to the total sorption amount in the whole process, and accounted for over 90% of the increase in the total sorption amount at initial 5 h. The influence of the slow compartment on the increase in the total sorption amount became principal (above 90%) in the subsequent stage approximately from 9 h or 25 h to the apparent equilibrium at 265 h. The results proposed the different sorption behaviors of the mathematically classified compartments for BDE-28 and BDE-47, which may correspond to the different soil components, such as soil organic fractions with amorphous and condensed structures, respectively.


Asunto(s)
Bifenilos Polibrominados/química , Contaminantes del Suelo/química , Absorción , Adsorción , Éteres Difenilos Halogenados , Cinética , Modelos Químicos
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