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1.
Mol Cancer Res ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546386

RESUMO

Hepatitis B viral (HBV) persistent infection plays a significant role in hepatocellular carcinoma (HCC) tumorigenesis. Many studies have revealed the pivotal roles of N6-methyladenosine (m6A) in multiple cancers, while the regulatory mechanism in stemness maintenance of HBV persistent infection-related HCC remains elusive. Here, we demonstrated that the level of m6A modification was downregulated by HBV in HBV-positive HCC, through enhanced stability of ALKBH5 mRNA. More specifically, we also identified that ALKBH5 mRNA was functionally required for the stemness maintenance and self-renewal in the HBV-positive HCC, but dispensable in HBV-negative HCC. Mechanistically, ALKBH5 demethylated the m6A modification in the 3'UTR region of the oncogenic gene SNAI2 to prevent the recognition of YTHDF2 therewith stabilize SNAI2 transcripts, contributing to cancer stem cell traits in HBV-positive HCC. Moreover, the expression of SNAI2 reversed the suppression of stemness properties by knocking down ALKBH5. Additionally, ALKBH5/SNAI2 axis accelerates tumor immune evasion through activated ligand of immune checkpoint CD155. Our study unveiled that the ALKBH5 induces m6A demethylation of the SNAI2 as a key regulator in HBV-related HCC, and identifies the function of ALKBH5/SNAI2/YTHDF2 axis in promoting the stem-like cells phenotype and immune escape during HBV infection. Implications: HBV promotes hepatocellular carcinoma stemness maintenance through elevate m6A modification of SNAI2 in an ALKBH5-YTHDF2 dependent manner and increases the expression of the ligand of immune checkpoint CD155.

2.
Front Bioeng Biotechnol ; 11: 1133090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122853

RESUMO

Organoids are advancing the development of accurate prediction of drug efficacy and toxicity in vitro. These advancements are attributed to the ability of organoids to recapitulate key structural and functional features of organs and parent tumor. Specifically, organoids are self-organized assembly with a multi-scale structure of 30-800 µm, which exacerbates the difficulty of non-destructive three-dimensional (3D) imaging, tracking and classification analysis for organoid clusters by traditional microscopy techniques. Here, we devise a 3D imaging, segmentation and analysis method based on Optical coherence tomography (OCT) technology and deep convolutional neural networks (CNNs) for printed organoid clusters (Organoid Printing and optical coherence tomography-based analysis, OPO). The results demonstrate that the organoid scale influences the segmentation effect of the neural network. The multi-scale information-guided optimized EGO-Net we designed achieves the best results, especially showing better recognition workout for the biologically significant organoid with diameter ≥50 µm than other neural networks. Moreover, OPO achieves to reconstruct the multiscale structure of organoid clusters within printed microbeads and calibrate the printing errors by segmenting the printed microbeads edges. Overall, the classification, tracking and quantitative analysis based on image reveal that the growth process of organoid undergoes morphological changes such as volume growth, cavity creation and fusion, and quantitative calculation of the volume demonstrates that the growth rate of organoid is associated with the initial scale. The new method we proposed enable the study of growth, structural evolution and heterogeneity for the organoid cluster, which is valuable for drug screening and tumor drug sensitivity detection based on organoids.

3.
Biomed Opt Express ; 14(4): 1703-1717, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078050

RESUMO

Patient-derived organoids (PDOs) serve as excellent tools for personalized drug screening to predict clinical outcomes of cancer treatment. However, current methods for efficient quantification of drug response are limited. Herein, we develop a method for label-free, continuous tracking imaging and quantitative analysis of drug efficacy using PDOs. A self-developed optical coherence tomography (OCT) system was used to monitor the morphological changes of PDOs within 6 days of drug administration. OCT image acquisition was performed every 24 h. An analytical method for organoid segmentation and morphological quantification was developed based on a deep learning network (EGO-Net) to simultaneously analyze multiple morphological organoid parameters under the drug's effect. Adenosine triphosphate (ATP) testing was conducted on the last day of drug treatment. Finally, a corresponding aggregated morphological indicator (AMI) was established using principal component analysis (PCA) based on the correlation analysis between OCT morphological quantification and ATP testing. Determining the AMI of organoids allowed quantitative evaluation of the PDOs responses to gradient concentrations and combinations of drugs. Results showed that there was a strong correlation (correlation coefficient >90%) between the results using the AMI of organoids and those from ATP testing, which is the standard test used for bioactivity measurement. Compared with single-time-point morphological parameters, the introduction of time-dependent morphological parameters can reflect drug efficacy with improved accuracy. Additionally, the AMI of organoids was found to improve the efficiency of 5-fluorouracil(5FU) against tumor cells by allowing the determination of the optimum concentration, and the discrepancies in response among different PDOs using the same drug combinations could also be measured. Collectively, the AMI established by OCT system combined with PCA could quantify the multidimensional morphological changes of organoids under the drug's effect, providing a simple and efficient tool for drug screening in PDOs.

4.
Front Vet Sci ; 9: 1004932, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36187830

RESUMO

Background: Fasciola gigantica, a tropical liver fluke, infects buffalo in Asian and African countries, causing significant economic losses and posing public health threats. The diagnostic of buffalo fascioliasis caused by F. gigantica is vital in fascioliasis control and preventation. The 22nd gel filtration chromatography fraction of F. gigantica Excretory-Secretory Products (FgESP), namely Fasciola 22 (F22), which was used as a diagnostic antigen in indirect ELISA, has demonstrated great potential for fascioliasis diagnosing. In the absence of rapid diagnostic methods, the use of a colloidal gold immunochromatographic strip based on F22 was applied to detect F. gigantica infection in buffalo. Methods: In the present study, the 22nd gel filtration chromatography fraction of FgESP (F22) was used as an antigen to establish the colloidal gold-based immunochromatographic strip (ICS). The nitrocellulose membrane was incubated with F22 at the test line (T line) and goat anti-mouse secondary antibody at the control line (C line). The mouse anti-buffalo secondary antibody 2G7 conjugated to colloidal gold particles was used as the detection system for line visualization. The strip was assembled and developed by optimizing reaction conditions. The sensitivity, specificity, stability, and early diagnostic value of the strip were evaluated employing buffalo-derived sera. Results: An immunochromatographic strip for the rapid detection of antibodies against F. gigantica-FgICS was developed. The strip demonstrated high sensitivity and specificity. Sensitivity tests confirmed positive results even when the positive reference serum was diluted 4,096 times. Except for one Schistosoma japonicum-positive serum that tested positive via FgICS, specificity tests confirmed no cross-reactivity with other positive sera of Schistosoma japonicum and Babesia bovis. The strip remained stable after storage at 4°C for up to 3 months. In infected buffalo, antibodies could be detected as early as 14-21 days post-infection. The detection of 17 positive sera yielded an 82.4% positive rate via FgICS vs. a 100.0% positive rate via ELISA based on FgESP. For FgICS, the 95% confidence interval of sensitivity was 84.8-95.4%, while specificity was 4.2-14.7%. Conclusion: The immunochromatographic strip FgICS developed in this study provides a simple and rapid method of F. gigantica antibody detection and infected buffalo monitoring in the field.

5.
Parasitol Res ; 121(6): 1709-1718, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35416490

RESUMO

Buffaloes, as highly susceptible definitive hosts of Fasciola gigantica, suffer from a high infection rate of fasciolosis, which causes enormous economic losses. Repeat infection is responsible for this high rate; thus, elucidating the protective immunity mechanism in repeat infection is decisive in fasciolosis prevention. Herein, a secondary experimental infection model was established to preliminarily reveal the protective immunity that occurs in repeat infection. In brief, animals were assigned to three groups: group A (uninfected control), group B (primary infection) and group C (secondary infection). Buffaloes were autopsied 20 weeks post-infection for measurements of the recovered flukes and hepatic examination. In addition, the detection of specific antibody (IgG) responses to F. gigantica excretory-secretory product (FgESP) throughout the whole period and weight gain throughout the first 4 months as a percentage (%) of the starting weight were also determined. The serum hepatic enzyme gamma glutathione transferase (GGT) levels were monitored to assess hepatic damage throughout the study period. Infection establishment was compared between group B and group C. Similar specific IgG patterns were observed between group B and group C, and hepatic damage was more severe in group C than group B. Significant differences in weight gain as a percentage of the start weight were observed between group A and group B at the 3rd and 4th months postprimary infection, while significant differences were not observed between group A and group C or group B and group C. Our results suggest that challenge infection cannot induce resistance against F. gigantica in buffaloes, which is consistent with the protective immunity against Fasciola hepatica reinfection observed in sheep and goats.


Assuntos
Bison , Fasciola , Fasciolíase , Doenças dos Ovinos , Animais , Anticorpos Anti-Helmínticos , Búfalos , Fasciolíase/veterinária , Imunoglobulina G , Ovinos , Aumento de Peso
6.
Engineering (Beijing) ; 17: 161-169, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34150352

RESUMO

Understanding the immunological characteristics of monocytes-including the characteristics associated with fibrosis-in severe coronavirus disease 2019 (COVID-19) is crucial for understanding the pathogenic mechanism of the disease and preventing disease severity. In this study, we performed single-cell transcriptomic sequencing of peripheral blood samples collected from six healthy controls and 14 COVID-19 samples including severe, moderate, and convalescent samples from three severely/critically ill and four moderately ill patients. We found that the monocytes were strongly remodeled in the severely/critically ill patients with COVID-19, with an increased proportion of monocytes and seriously reduced diversity. In addition, we discovered two novel severe-disease-specific monocyte subsets: Mono 0 and Mono 5. These subsets expressed amphiregulin (AREG), epiregulin (EREG), and cytokine interleukin-18 (IL-18) gene, exhibited an enriched erythroblastic leukemia viral oncogene homolog (ErbB) signaling pathway, and appeared to exhibit pro-fibrogenic and pro-inflammation characteristics. We also found metabolic changes in Mono 0 and Mono 5, including increased glycolysis/gluconeogenesis and an increased hypoxia inducible factor-1 (HIF-1) signaling pathway. Notably, one pre-severe sample displayed a monocyte atlas similar to that of the severe/critical samples. In conclusion, our study discovered two novel severe-disease-specific monocyte subsets as potential predictors and therapeutic targets for severe COVID-19. Overall, this study provides potential predictors for severe disease and therapeutic targets for COVID-19 and thus provides a resource for further studies on COVID-19.

7.
Vet Parasitol ; 300: 109585, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34740153

RESUMO

Fasciolosis is harmful to ruminant husbandry worldwide. Given the superficial survey on Fasciolosis infection in Guangxi, the main buffalo breeding area in China, an in-depth investigation in the infection of buffaloes in Nanning, the capital of Guangxi Zhuang Autonomous Region, with Fasciola (Platyhelminthes: Trematoda: Digenea) species will provide a theoretical support for the control and prevention of Fasciolosis infection in buffaloes. Five water buffalo livers were collected from an abattoir in Nanning every 2 weeks from June 2018 to April 2019, and a total of 101 livers were obtained. All livers were then dissected to observe the liver lesions caused by the flukes. Afterwards, Fasciola spp. collected from Fasciolosis-infected livers were numbered and measured. Then, the livers infected with more than 3 flukes were marked, and 3 flukes were picked from each liver according to their morphological differences, such as body length (BL), body maximum width (BW) and length-width ratio (BL/BW). Moreover, these Fasciola spp. worms were selected for molecular biological analysis. The second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) was amplified by polymerase chain reaction (PCR) and sequenced. Finally, sequential and phylogenetic analyses were also performed. The infection rate was 38.6 % according to anatomic examination, and the livers infected by Fasciola spp. were damaged seriously. The principal manifestations were the enlargement of the liver and protrusion of the bile ducts. In some cases, the bile duct wall became inflamed and rough, in which some sediment such as phosphate could be easily found. After dissection, 1243 Fasciola spp. flukes were collected from 39 out of 101 livers. The morphometric measurements obtained from the present study showed that the BL/BW ranged from 1.42-10.25. However, it might vary considerably among different geographical locations and could not be used as an accurate method for the identification of Fasciola spp.. Analysis of the ITS-2 sequences showed that 83 out of 87 flukes had 100 % homology with each other, and the other 4 flukes with 99.3 % homology possessed a nucleotide polymorphism. A unique position (271) was detected in flukes in Nanning isolates. Phylogenetic analysis indicated that all the flukes were Fasciola gigantica, and no Fasciola hepatica or the intermediate form was found in this study.


Assuntos
Doenças dos Bovinos , Fasciola , Fasciolíase , Animais , Búfalos , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , China/epidemiologia , DNA de Helmintos , Fasciola/genética , Fasciolíase/epidemiologia , Fasciolíase/veterinária , Filogenia
8.
J Cancer ; 12(2): 335-342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33391430

RESUMO

Background: Noninvasive stool-based DNA methylation testing emerges as a new approach for detecting colorectal cancer (CRC). However, its feasibility for early detection of CRC and precancerous lesions in the Chinese population remains inconclusive. Methods: In this study, we establish a possibilities screening method (sDNA-FOBT) for detecting CRC and precancerous lesions (hyperplastic polyps [HP] and adenomas [AD]) and evaluate its detection performance in the Chinese population. This method combined a molecular assay of DNA methylation markers (BMP3, NDRG4, and SDC2) with the human hemoglobin test (FOBT) in stool samples. Results: The sensitivity of sDNA-FOBT was 85.42% for CRC, 85.71% for AD, and 28.21% for HP, respectively, at the specificity of 92%. The diagnostic efficacy of sDNA-FOBT for detecting CRC and precancerous lesions was significantly higher than FOBT alone (sensitivity: 61.70% vs. 51.06%, P<0.01; AUC: 0.78 vs. 0.72, P<0.001), especially for CRC (AUC: 0.91 vs. 0.86, P<0.001) and AD (AUC: 0.91 vs. 0.75, P<0.05). No significant difference was observed between the detection sensitivity of sDNA-FOBT and the clinical variables. Notably, compared with FOBT, sDNA-FOBT was more effective in the detection of CRC and precancerous lesions in the patients aged >50 y (62.34% vs 54.55%, P<0.05). Conclusion: Our results demonstrate that sDNA-FOBT is a promising method for screening CRC and precancerous lesions in the Chinese population. Further studies are required to validate the results in a larger sample capacity.

9.
Cancer Manag Res ; 12: 9621-9626, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116821

RESUMO

BACKGROUND: Zinc finger and BTB domain-containing 4 (ZBTB4), which is a transcriptional regulator, has been identified as a tumor suppressor in several human carcinomas. So far, however, the expression of ZBTB4 and its possible clinical significance in colorectal cancer (CRC) remain unknown. MATERIALS AND METHODS: The mRNA and protein expressions of ZBTB4 in five CRC cell lines were respectively detected by performing qRT-PCR and Western Blotting. ZBTB4 expression in colorectal tissue specimens was determined, and subsequently its relationship with clinical prognosis was examined. RESULTS: The mRNA and protein expressions of ZBTB4 were significantly decreased in all the five CRC cell lines compared with normal colonic epithelial cells. Consistent with the cell data, immunohistochemical results showed that as compared with the normal colorectal tissue samples, ZBTB4 protein expression was clearly lower in the CRC tissue samples, especially in CRC patients with liver metastasis. In addition, low-expressed ZBTB4 was found associated with tumor metastasis stage (P=0.0003) and level of carcinoembryonic antigen (CEA) (P=0.0004). The overall survival (OS) and recurrence-free survival (RFS) in the ZBTB4-low group were significantly lower than those in the ZBTB4-high group (P=0.0007 and P=0.0077). CONCLUSION: The current findings showed that patients with high-expressed ZBTB4 in CRC tissues may develop a better prognosis, and ZBTB4 could serve as a potential therapeutic target for CRC treatment.

10.
J Cancer ; 11(20): 6050-6058, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922545

RESUMO

Background: Metastasis is the primary cause of death in colorectal cancer (CRC); the underlying mechanisms remain partly unknown. In this study, we aim to investigate the value of HOXA11-AS in survival evaluation and the potential role of HOXA11-AS/miR-149-3p axis in the CRC metastasis. Methods: The expressions of HOXA11-AS, both in obtained CRC samples and adjacent noncancerous tissues, were analyzed in survival evaluation. Competing endogenous RNAs (CeRNAs) Analysis were employed to reveal the potential relationship between HOXA11-AS and miR-149-3p. It was further confirmed by Quantitative real-time polymerase chain reaction (qRT-PCR) and Dual-luciferase reporter assay. Migration and invasion assay were used to verify the potential role of HOXA11-AS and miR-149-3p in the regulation of CRC metastasis. The potential pathway was explored by Western blot analysis. Results: The expression of HOXA11-AS in the CRC tissue is significantly higher than the expression in adjacent noncancerous tissue (p<0.0001). High expressions of HOXA11-AS were noticeably correlated with clinicopathologic characteristics including advanced clinical stage (p=0.021), larger tumor size (p<0.001) and frequent tumor recurrence (p=0.001). The overall survival in HOXA11-AS-High group was significantly shorter than the HOXA11-AS-Low group (p<0.001). Advanced clinical stage, tumor size and high expression of HOXA11-AS were showed as independent prognostic prediction factors for the 5-year tumor relapse of CRC patients (p<0.001). HOXA11-AS acts as a potential molecular sponge for miR-149-3p, in the promotion of CRC metastasis. In the miR-149-3p mimic-treated group, the expression of E-cadherin was increased, whereas the expression of N-cadherin, Snail, Slug, TGF-ß1, Wnt2b, Twist and C/EBPß was decreased. Conclusion: This study demonstrates that high expression of HOXA11-AS is correlated with CRC progression and poor prognosis and may promote metastasis via EMT by modulating miR-149-3p.

11.
Onco Targets Ther ; 13: 635-646, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021305

RESUMO

BACKGROUND: To understand the biological effect of gut microbiome on the progression of colorectal cancer (CRC), we sequenced the V3-V4 region of the 16S rRNA gene to illustrate the overall structure of microbiota in the CRC patients. METHODS: In this study, a total of 66 CRC patients were dichotomized into different groups based on the following characteristics: paired tumor and adjacent normal tissues, distal and proximal CRC segments, MMR (-) and MMR (+), different TNM staging and clinic tumor staging. RESULTS: By sequencing and comparing the microbial assemblages, our results indicated that 7 microbe genus (Fusobacterium, Faecalibacterium, Akkermansia, Ruminococcus2, Parabacteroides, Streptococcus, and f_Ruminococcaceae) were significantly different between tumor and adjacent normal tissues; and 5 microbe genus (Bacteroides, Fusobacterium, Faecalibacterium, Parabacteroides, and Ruminococcus2) were significantly different between distal and proximal CRC segments; only 2 microbe genus (f_Enterobacteriaceae and Granulicatella) were significantly different between MMR (-) and MMR (+); but there was no significant microbial difference were detected neither in the TNM staging nor in the clinic tumor staging. CONCLUSION: All these findings implied a better understanding of the alteration in the gut microbiome, which may offer new insight into diagnosing and therapying for CRC patients.

12.
World J Gastrointest Oncol ; 11(9): 717-728, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31558976

RESUMO

BACKGROUND: Impaired anastomotic healing is one of the major complications resulting from radical resection in colorectal cancer (CRC). Accumulating evidence suggests that intestinal microbiota is correlated with anastomotic healing. AIM: To explore the microbiota structural shift in margin-surrounding mucosa and evaluate the predictive ability of selected bacterial taxa for impaired anastomotic healing. METHODS: Margin-surrounding mucosa samples derived from 37 patients were collected to characterize the microbial community structure by 16s rRNA gene sequencing. The patients were divided into two groups according to the healing status of anastomoses: well-healing group (n = 30) and impaired-healing group (n = 7). Statistic differences in bacteria taxa were compared by Wilcoxon test and chi-squared test. The predictive ability of the selected bacterial taxa for the healing status of anastomoses was evaluated by the area under the receiver operator characteristic curve. RESULTS: Community structure shifts were observed in the impaired-healing group and well-healing group. Six bacterial species were found to be significantly correlated with anastomotic healing, and among these species, Alistipes shahii, Dialister pneumosintes, and Corynebacterium suicordis were considered as the predictive factors. Taking the known risk factor age into consideration, Alistipes shahii, Dialister pneumosintes, and Corynebacterium suicordis improved predictive ability for the healing status of anastomoses. CONCLUSION: These data show that Alistipes shahii, Dialister pneumosintes, and Corynebacterium suicordis could be considered as supplementary factors in the prediction of anastomosis healing status in patients after CRC radical resection.

13.
Emerg Microbes Infect ; 6(12): e112, 2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29259328

RESUMO

Secondary bacterial lung infection (SBLI) is a serious complication in patients with H7N9 virus infection, and increases disease severity. The oropharyngeal (OP) microbiome helps prevent colonisation of respiratory pathogens. We aimed to investigate the OP microbiome of H7N9 patients with/without secondary bacterial pneumonia using 16S rRNA gene sequencing. OP swab samples were collected from 51 H7N9 patients (21 with SBLI and 30 without) and 30 matched healthy controls (HCs) and used for comparative composition, diversity and richness analyses of microbial communities. Principal coordinates analysis successfully distinguished between the OP microbiomes of H7N9 patients and healthy subjects, and the OP microbiome diversity of patients with SBLI was significantly increased. There was significant dysbiosis of the OP microbiome in H7N9 patients, with an abundance of Leptotrichia, Oribacterium, Streptococcus, Atopobium, Eubacterium, Solobacterium and Rothia species in patients with SBLI, and Filifactor, Megasphaera and Leptotrichia species in patients without SBLI, when compared with HCs. Importantly, Haemophilus and Bacteroides species were enriched in HCs. These findings revealed dysbiosis of the OP microbiota in H7N9 patients, and identified OP microbial risk indicators of SBLI, suggesting that the OP microbiome could provide novel and non-invasive diagnostic biomarkers for early microbiota-targeted prophylactic therapies for SBLI prevention.


Assuntos
Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Coinfecção/microbiologia , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Influenza Humana/virologia , Pneumopatias/microbiologia , Orofaringe/microbiologia , Adulto , Idoso , Bactérias/classificação , Bactérias/genética , Infecções Bacterianas/etiologia , Fenômenos Fisiológicos Bacterianos , Coinfecção/etiologia , Feminino , Humanos , Subtipo H7N9 do Vírus da Influenza A/genética , Influenza Humana/complicações , Pneumopatias/etiologia , Masculino , Pessoa de Meia-Idade , Filogenia
14.
J Environ Sci (China) ; 35: 108-114, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26354699

RESUMO

The selection of cadmium-excluding cultivars has been used to minimize the transfer of cadmium into the human food chain. In this experiment, five Chinese soybean plants were grown in three soils with different concentrations of Cd (0.15, 0.75 and 1.12mg/kg). Variations in uptake, enrichment, and translocation of Cd among these soybean cultivars were studied. The results indicated that the concentration of Cd in seeds that grew at 1.12mg/kg Cd in soils exceeded the permitted maximum levels in soybeans. Therefore, our results indicated that even some soybean cultivars grown on soils with permitted levels of Cd might accumulate higher concentrations of Cd in seeds that are hazardous to human health. The seeds of these five cultivars were further assessed for interactions between Cd and other mineral nutrient elements such as Ca, Cu, Fe, Mg, Mn and Zn. High Cd concentration in soil was found to inhibit the uptake of Mn. Furthermore, Fe and Zn accumulations were found to be enhanced in the seeds of all of the five soybean cultivars in response to high Cd concentration. Cultivar Tiefeng 31 was found to fit the criteria for a Cd-excluding cultivar under different concentrations of Cd in soils.


Assuntos
Cádmio/metabolismo , Glycine max/metabolismo , Poluentes do Solo/metabolismo , Relação Dose-Resposta a Droga , Sementes/química , Glycine max/genética
15.
J Hazard Mater ; 225-226: 91-8, 2012 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-22621879

RESUMO

Long-term field and modeling studies were performed to measure and predict occurrence, accumulation, attenuation and priority of typical antibiotics in sediments of the Dagu River in China. The results indicated that the concentrations of antibiotics ranged from lower than the limit of detection to 12.4mg/kg, depending on the accumulation time of these antibiotics in sediments. Compared with the residential and industrial areas, the agricultural region of the watershed was a major source of antibiotic contamination in sediments. Accumulation and attenuation kinetics models were established and successfully applied in the field study. For instance, by 2100, the accumulation model predicted that the concentrations of roxithromycin and oxytetracycline would rise to 13 and 7.3mg/kg, respectively. The first and second order attenuation kinetics models revealed the fate of these antibiotics along the downstream and upstream sediments, respectively. The half-life distances of antibiotic attenuation ranged from 3.5 to 12.4km. Based on the contamination level and trend, a priority factor and an accumulation growth factor were defined to identify the priority pollutants from the antibiotics. Gentamicin and roxithromycin were recognized as the top priority pollutants among the tested antibiotics. In the future, a wider applicability of the methods and models needs to be explored and suggested.


Assuntos
Antibacterianos/análise , Sedimentos Geológicos/análise , Modelos Teóricos , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Cinética , Rios
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