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This paper investigated the operational characteristics and self-regulation mechanism of the partial denitrification/anammox (PD/A) granular system under the stress of oxytetracycline (OTC), an emerging pollutant that accumulates in municipal wastewater treatment plants through various pathways, posing significant challenges for its future promotion in engineering applications. The results indicated that OTC concentrations below 100 mg/L intensified its short-term inhibition on the PD/A granular sludge system, decreasing functional bacterial activity, while between 150 and 300 mg/L, PD's NO3--N to NO2--N conversion ability diminished, and Anammox activity was significantly suppressed. Under long-term high OTC stress (20-30 mg/L), nitrogen removal suffered, and batch tests revealed significant inhibition of PD's NO3--N to NO2--N conversion, dropping from 73.77 % to 50.17 %. Anammox bacteria activity sharply declined from 1.81 to 0.39 mg N/gVSS/h under OTC stress. Extracellular polymeric substances (EPS) content rose from 185.39 to 210.86 mg/gVSS, indicating PD/A sludge's self-protection mechanism. However, EPS content fell due to cell lysis at high OTC (30 mg/L). The decreasing relative abundance of Candidatus_Brocadia (2.32 % to 0.93 %) and Thaure (12.63 % to 7.82 %) was a key factor in the gradual deterioration of denitrification performance. This study was expected to provide guidance for the PD/A process to cope with the interference of antibiotics and other emerging pollutants (short-term shock and long-term stress).
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Desnitrificación , Oxitetraciclina , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Antibacterianos , Reactores Biológicos , Aguas Residuales/químicaRESUMEN
Background: Colorectal, and gastric cancers have the second, and fourth mortality rates worldwide, respectively. Endoscopic screening is a crucial diagnostic tool for colorectal, and gastric cancers. Effective interventions can improve adherence to endoscopic screening in high-risk populations, which is important for cancer prevention and mortality reduction. This study aimed to identify interventions that could improve adherence to endoscopic screening for cancer in high-risk populations. Methods: Combination keywords including colorectal cancer, gastric cancer, screening adherence, and interventions were used to search for articles in PubMed, Web of Science, Cochrane Library, and MEDLINE Complete. The review methodology was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-SCR). Results: A total of 12 articles were included in this review: 9 randomized controlled trials(RCT) and 3 quasi-experimental studies(QEDs). Among the extracted studies, 11 were about colorectal cancer, and 1 was about gastric cancer. Most studies used lecture-based or Information Technology-based health education interventions. Narrative interventions have proven to be novel and effective approaches for promoting adherence to endoscopic screening. Health education interventions included cancer epidemiology, cancer risk factors, warning symptoms, and screening methods. Conclusion: All interventions involved were effective in increasing individual knowledge of cancer-related endoscopic screening, willingness to undergo screening, and screening behaviors. These findings provide a reference for designing endoscopy-related cancer screening interventions.
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INTRODUCTION: Colorectal cancer (CRC) is associated with a high incidence and mortality rate. Fecal occult blood test (FOBT) is effective in the prevention of CRC. OBJECTIVE: This study aimed to assess knowledge and beliefs regarding FOBT-based screening. METHODS: This study used PubMed, Cochrane Library, MEDLINE Complete, and Web of Science to search for articles. Original full-text studies in English language focusing on knowledge and beliefs of FOBT screening were included. RESULTS: A total of 32 articles were included. This study indicated that the population in most studies had inadequate knowledge and lacked beliefs toward FOBT-based screening. Most of the extracted studies showed that less than half of the participants had heard of FOBT-based screening. Six studies showed that less than 50% of participants had knowledge of FOBT age. Three studies found that less than 40% of participants were aware of the screening interval. Some participants perceived the benefits of FOBT-based screening, while others perceived many barriers to the test. CONCLUSION: Participants' knowledge and belief in FOBT-based screening were insufficient. This review highlights the importance of educational programs to increase knowledge and beliefs regarding FOBT-based screening. It is important to include FOBT-based screening in the health care system to promote the secondary prevention of CRC.
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Neoplasias Colorrectales , Sangre Oculta , Humanos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/prevención & control , Neoplasias Colorrectales/epidemiología , Detección Precoz del Cáncer , Tamizaje MasivoRESUMEN
BACKGROUND: Periprosthetic joint infection (PJI) is one of the worst complications following total joint arthroplasty (TJA). Unfortunately, effective prevention strategies to reduce the burden of PJI have not been fully determined in hip replacement patients with fracture and non-fracture. OBJECTIVE: This study aimed to analyze and compare the demographic characteristics, microbiological profiles and antibiotic resistance of PJI after hip replacement between patients with fracture and non-fracture. METHODS: We retrospectively analyzed the data of 132 patients who treated PJI. There were divided into two groups: non-fracture group (64 patients infected after hip replacement for fracture) and non-fracture group (68 patients infected after hip replacement for non-fracture). Microorganisms were obtained from the synovial fluid and infected necrotic tissue in the joint capsule, medullary cavity, or acetabulum in all patients, and microbiological profiles and antibiotic resistance were evaluated. RESULTS: Coagulase-negative staphylococci (CoNS) were the most common pathogenic microorganisms in all patients. Methicillin-resistant Staphylococcus (MRS) accounted for 25% in all pathogenic microbes. Staphylococci showed high drug resistance rates to clindamycin, levofloxacin, and all of the first- and second-generation cephalosporins. MRS isolates in non-fracture group had higher drug resistance rates to clindamycin and levofloxacin than than those in fracture group. Gram-negative bacilli (GNB) showed high drug resistance rates to Aztreonam, gentamicin and all of the third- and fourth-generation cephalosporins. Furthermore, GNB isolates in the non-fracture group showed higher resistance rates to gentamicin and all of the third- and fourth-generation cephalosporins. CONCLUSIONS: MRS isolates in the non-fracture group showed higher drug resistance rates to clindamycin and levofloxacin, and GNB isolates in non-fracture group showed higher drug resistance rates to gentamicin and all of the third- and fourth-generation cephalosporins.
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Artroplastia de Reemplazo de Cadera , Fracturas Óseas , Staphylococcus aureus Resistente a Meticilina , Infecciones Relacionadas con Prótesis , Humanos , Clindamicina/uso terapéutico , Antibacterianos/uso terapéutico , Levofloxacino/uso terapéutico , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Relacionadas con Prótesis/prevención & control , Estudios Retrospectivos , Farmacorresistencia Microbiana , Gentamicinas/uso terapéutico , Cefalosporinas/uso terapéuticoRESUMEN
OBJECTIVE: To evaluate the general population's awareness of and attitudes toward Helicobacter pylori (HP) screening and health behaviours. DESIGN: Cross-sectional study. SETTING: Hengyang, Hunan Province, China. PARTICIPANTS: Using stratified cluster random sampling, a pretested structured questionnaire was used to interview members of the general population aged ≥18 years. PRIMARY AND SECONDARY OUTCOME MEASURES: Knowledge of and attitudes toward HP screening and associated health behaviours, sociodemographic factors associated with HP knowledge, and screening behaviours. RESULTS: This study featured 1042 participants. The average knowledge score was 11 (QL=4, QU=20, range 0-29). Approximately 68.9% of the participants said they had heard of HP, but 67.5% had never had an HP test. The most common reasons for not undergoing screening were 'no symptoms' (55.7%) and 'lack of knowledge regarding the benefits of the test' (21.1%). Independent factors related to knowledge included age, education level, occupation, HP infection, frequency of drinking unboiled water (p<0.05). Factors independently associated with screening behaviour included occupation, average monthly income, presence/absence of indigestion, stomach discomfort or pain, and/or stomach disease and knowledge score (p<0.05). Overall, 941 (90.3%) participants never used anti-HP toothpaste, and 442 (40.5%) never used serving spoons or chopsticks. The risk factors for HP infection included eating out and eating in groups (p<0.05). CONCLUSION: In China, the general population has poor knowledge of HP, but most people have a positive attitude towards HP screening. Being asymptomatic and lacking knowledge about testing were the main reasons for reluctance to be screened. These results highlight the urgent need for educational activities to raise awareness, enhance screening rates for HP, and encourage people to adopt a healthy lifestyle.
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Infecciones por Helicobacter , Helicobacter pylori , Adolescente , Adulto , China/epidemiología , Estudios Transversales , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Humanos , Encuestas y CuestionariosRESUMEN
Colorectal cancer (CRC) is the second leading cause of cancer death in the world. Immunotherapy using monoclonal antibodies, immune-checkpoint inhibitors, adoptive cell therapy, and cancer vaccines has raised great hopes for treating poor prognosis metastatic CRCs that are resistant to the conventional therapies. However, high inter-tumor and intra-tumor heterogeneity hinder the success of immunotherapy in CRC. Patients with a similar tumor phenotype respond differently to the same immunotherapy regimen. Mutation-based classification, molecular subtyping, and immunoscoring of CRCs facilitated the multi-aspect grouping of CRC patients and improved immunotherapy. Personalized immunotherapy using tumor-specific neoantigens provides the opportunity to consider each patient as an independent group deserving of individualized immunotherapy. In the recent decade, the development of sequencing and multi-omics techniques has helped us classify patients more precisely. The expansion of such advanced techniques along with the neoantigen-based immunotherapy could herald a new era in treating heterogeneous tumors such as CRC. In this review article, we provided the latest findings in immunotherapy of CRC. We elaborated on the heterogeneity of CRC patients as a bottleneck of CRC immunotherapy and reviewed the latest advances in personalized immunotherapy to overcome CRC heterogeneity.
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In contrast to conventional cancer treatment, in personalized cancer medicine each patient receives a specific treatment. The response to therapy, clinical outcomes, and tumor behavior such as metastases, tumor progression, carcinogenesis can be significantly affected by the heterogeneous tumor microenvironment (TME) and interpersonal differences. Therefore, using native tumor microenvironment mimicking models is necessary to improving personalized cancer therapy. Both in vitro 2D cell culture and in vivo animal models poorly recapitulate the heterogeneous tumor (immune) microenvironments of native tumors. The development of 3D culture models, native tumor microenvironment mimicking models, made it possible to evaluate the chemoresistance of tumor tissue and the functionality of drugs in the presence of cell-extracellular matrix and cell-cell interactions in a 3D construction. Various personalized tumor models have been designed to preserving the native tumor microenvironment, including patient-derived tumor xenografts and organoid culture strategies. In this review, we will discuss the patient-derived organoids as a native tumor microenvironment mimicking model in personalized cancer therapy. In addition, we will also review the potential and the limitations of organoid culture systems for predicting patient outcomes and preclinical drug screening. Finally, we will discuss immunotherapy drug screening in tumor organoids by using microfluidic technology.
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Matriz Extracelular/genética , Neoplasias/terapia , Organoides/inmunología , Microambiente Tumoral/genética , Técnicas de Cultivo de Célula , Matriz Extracelular/inmunología , Humanos , Inmunoterapia , Neoplasias/inmunología , Neoplasias/patología , Medicina de Precisión , Microambiente Tumoral/inmunologíaRESUMEN
PURPOSE: Although doxorubicin chemotherapeutic drug is commonly used to treat various solid and hematological tumors, its clinical use is restricted because of its adverse effects on the normal cells/tissues, especially cardiotoxicity. The use of resveratrol may mitigate the doxorubicin-induced cardiotoxic effects. For this aim, we systematically reviewed the potential chemoprotective effects of resveratrol against the doxorubicin-induced cardiotoxicity. METHODS: In the current study, a systematic search was performed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline for the identification of all relevant studies on "the role of resveratrol on doxorubicin-induced cardiotoxicity" in the electronic databases of Web of Science, PubMed, and Scopus up to March 2021 using search terms in their titles and abstracts. Two hundred and eighteen articles were screened in accordance with a predefined set of inclusion and exclusion criteria. Finally, 33 eligible articles were included in this systematic review. RESULTS: The in vitro and in vivo findings demonstrated a decreased cell survival, increased mortality, decreased heart weight, and increased ascites in the doxorubicin-treated groups compared to the control groups. The combined treatment of resveratrol and doxorubicin showed an opposite pattern than the doxorubicin-treated groups alone. Furthermore, this chemotherapeutic agent induced the biochemical and histopathological changes on the cardiac cells/tissue; however, the results (for most of the cases) revealed that these alterations induced by doxorubicin were reversed near to normal levels (control groups) by resveratrol coadministration. CONCLUSION: The results of this systematic review stated that coadministration of resveratrol alleviates the doxorubicin-induced cardiotoxicity. Resveratrol exerts these chemoprotective effects through several main mechanisms of antioxidant, antiapoptosis, and anti-inflammatory.
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Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Apoptosis/efectos de los fármacos , Cardiotoxicidad/tratamiento farmacológico , Doxorrubicina/efectos adversos , Resveratrol/uso terapéutico , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Cardiotoxicidad/etiología , Humanos , Resveratrol/farmacologíaRESUMEN
OBJECTIVE: To assess the awareness, attitude and barriers of colorectal cancer screening among high-risk populations in China. DESIGN: A cross-sectional study was employed. SETTING: This study was conducted in nine hospitals in Hunan province, China. PARTICIPANTS: Individuals with a high-risk for colorectal cancer were interviewed using a pretested structured questionnaire. PRIMARY AND SECONDARY OUTCOME MEASURES: Knowledge, attitude towards colorectal cancer screening, sociodemographic factors associated with screening knowledge and behaviour and barriers of colorectal cancer screening. RESULTS: This study included 684 participants. The mean knowledge score was 11.86/24 (SD 4.84). But over 70% of them held a positive attitude towards screening. Only 13.3% had undergone colorectal cancer screening. Independent factors related to knowledge were education level of college or above, working as a white collar, higher income, having health insurance, having seen a doctor in the past year and with a high perceived risk (p<0.05). Factors independently associated with screening behaviour included personal history of colorectal disease, having seen a doctor in the past year, previous discussion of colorectal cancer screening, high perceived risk and better knowledge (p<0.05). Main reasons for not undergoing screening were no symptoms or discomfort (71.1%), never having thought of the disease or screening (67.4%) and no doctor advised me (29.8%). CONCLUSION: In China, the majority of high-risk people had deficient knowledge and had never undergone colorectal cancer screening. But most of them held a positive attitude towards the benefits of colorectal cancer screening. This has promising implications to design targeted educational campaigns and establish screening programmes to improve colorectal cancer awareness and screening participation. Healthcare professionals should advise high-risk individuals to participate in screening and inform them about cancer risk.
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Neoplasias Colorrectales , Detección Precoz del Cáncer , China , Neoplasias Colorrectales/diagnóstico , Estudios Transversales , Conocimientos, Actitudes y Práctica en Salud , Humanos , Tamizaje Masivo , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
Fenclorim (Fen) is a safener developed for pretilachlor (Pre) that can protect rice from injury caused by Pre but does not lower the weed control effects of Pre. Unfortunately, the mechanism of selective action of Fen between rice and weeds, such as Echinochloa crusgalli (barnyard grass), has not been clarified. In this study, the differences in physiology, biochemistry, and gene transcription between rice and E. crusgalli response to Fen were compared. Comparing the protection effects of Fen on plant growth, it was found that Fen significantly protected rice from Pre, but did not protect E. crusgalli. The detection of malondialdehyde (MDA) content and activities of antioxidant enzymes showed that Pre induced significant oxidative damage both in rice and E. crusgalli; however, Fen reduced oxidative damage in rice but not in E. crusgalli. Transcriptome analysis revealed that Fen induced more genes related to herbicide metabolism in rice than in E. crusgalli, especially the glutathione-S-transferase (GST) genes, with six upregulated in rice but no genes upregulated in E. crusgalli. Accordingly, the GST activity analysis showed that Fen increased the activity of rice instead of E. crusgalli. These results indicate that the elevation of detoxifying enzyme activities and antioxidative defense may be the mechanism of selective action of Fen in rice but not in E. crusgalli.
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Echinochloa , Herbicidas , Oryza , Antioxidantes , Echinochloa/genética , Herbicidas/farmacología , Oryza/genética , PirimidinasRESUMEN
OBJECTIVE: This study examined the trends in demographics, the distribution of microorganisms, and antibiotic resistance in patients with periprosthetic joint infection (PJI). METHODS: We conducted a retrospective study of 231 consecutive patients diagnosed with PJI in our hospital from January 2006 to December 2015 (93 and 138 patients diagnosed in 2006-2010 and 2011-2015, respectively). The linear-by-linear chi-squared test was used to assess the trends in demographics, the distribution of microorganisms, and antibiotic resistance. RESULTS: Gram-positive cocci accounted for 63.9% of all pathogens, and coagulase-negative Staphylococcus (CoNS) accounted for 38.1% of all isolates. The proportion of isolates identified as methicillin-resistant CoNS significantly increased over the study period (39.0% vs. 61.8%). In addition, the proportions of levofloxacin-resistant CoNS (4.9% vs. 21.8%) and Staphylococcus aureus (6.3% vs. 45.0%) isolates significantly increased over the study period. By contrast, the proportions of penicillin-resistant CoNS (82.9% vs. 40.0%) and S. aureus (75.0% vs. 30.0%) isolates decreased over the study period. CONCLUSION: Our research revealed changes in the distribution of microorganisms and antibiotic resistance profile of the pathogens responsible for PJI over time, which could complicate treatment. These findings may serve as a reference for strategies to prevent and empirically treat PJI in China.
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Infecciones Relacionadas con Prótesis , Infecciones Estafilocócicas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , China/epidemiología , Farmacorresistencia Microbiana , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Estudios Retrospectivos , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureusRESUMEN
BACKGROUND: Fenclorim (Fen) can effectively protect rice from pretilachlor (Pre) injury, but its effects on rice have not been formally evaluated; thus, the Fen mode of action for alleviating the phytotoxicity caused by Pre in rice is not clear. This study aimed to examine the biochemical and physiological effects of Fen on rice and to determine the changes induced by Fen at the transcriptome level. RESULT: The chlorophyll content of rice plants was significantly affected by Pre but not by Fen. The activity of oxidative stress enzymes showed that Fen did not elicit any changes in oxidative stress; however, it reduced lipid peroxidation and oxidative damage induced by Pre. Fen did not affect the uptake of Pre but did affect its persistence in rice. In a transcriptome experiment, Fen upregulated genes in a detoxification pathway. Overall, 25 genes related to detoxification were identified, including P450, GST, and GT. Moreover, qRT-PCR analysis showed that four P450 genes, CYP71Y83, CYP71K14, CYP734A2 and CYP71D55, and two GST genes, GSTU16 and GSTF5, were upregulated by Fen and/or Pre. CONCLUSION: Our work indicates that Fen acts in antioxidative defense in addition to enhancing the metabolism of herbicides in rice.
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Acetanilidas/metabolismo , Antioxidantes/metabolismo , Herbicidas/metabolismo , Oryza/efectos de los fármacos , Pirimidinas/metabolismo , Transcripción Genética/efectos de los fármacos , Genes de Plantas/efectos de los fármacos , Inactivación Metabólica , Oryza/enzimología , Oryza/genética , Oryza/fisiología , Plantones/enzimología , Transcriptoma/efectos de los fármacosRESUMEN
The existing form of ionizable organic contaminants (IOCs) could affect their adsorption characteristics to soil and biochar. In this study, 2 IOCs, namely, sulfadiazine and imazalil, were selected to study their adsorption by rice straw-derived biochar-amended soils, as well as the effect of pH and gallic acid on their adsorption. The results showed that the soil adsorption isotherms of the two ionizable organic contaminants could be fitted well by a linear equation and the Freundlich equation, and r2 was more than 0.80. The adsorption coefficient (Kd) in the three kinds of soil ranged from 0.262 to 4.07â¯Lâ¯kg-1 for sulfadiazine and from 3.11 to 96.5â¯Lâ¯kg-1 for imazalil. After the addition of biochar, the adsorption of sulfadiazine and imazalil in the soil increased. The adsorption of sulfadiazine by biochar gradually decreased with the increase in pH; the adsorption of imazalil increased when the pH increased from 2 to 5 and then gradually decreased with increasing pH. Gallic acid enhanced the adsorption of the two IOCs to pure soil and biochar-amended soil.
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Carbón Orgánico/química , Ácido Gálico/química , Oryza/química , Contaminantes del Suelo/análisis , Suelo/química , Adsorción , Concentración de Iones de Hidrógeno , Imidazoles/análisis , Sulfadiazina/análisisRESUMEN
[This corrects the article on p. 1802 in vol. 8, PMID: 28979249.].
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The existing form of an ionizable organic compound can simultaneously affect its soil adsorption and plant bioactivity. In this experiment, the adsorption and bioactivity of two weak acid herbicides (WAHs), imazethapyr and 2,4-D, were studied to explore the predominant mechanism by which the soil pH and the addition of biochar can influence the phytotoxicity of WAHs in soil. Then, the WAH concentration extracted by hollow fiber-based liquid-phase microextraction (CHF-LPME), the in situ pore water concentration (CIPW) and the added concentration (CAC) were employed to estimate the phytotoxicity. The results showed that with increased pH from 5.5 to 8.5, the phytotoxicity of the WAHs to rice increased about 1-fold in the soil, but decreased in aqueous solutions, the IC50 values for imazethapyr and 2,4-D at pH 5.0 were 3- and 2-fold higher than that at pH 8.0. In addition, the soil adsorption decreased, indicating that the adsorption process was the dominant factor for the variation of the phytotoxicity of the WAHs in the tested soil instead of the decreasing bioactivity. The concentration that inhibits plant growth by 50% (IC50) calculated by the CAC in different pH and biochar soils ranged from 0.619 to 3.826â¯mg/kg for imazethapyr and 1.871-72.83â¯mg/kg for 2,4-D. The coefficient of variation (CV) of the IC50 values reached 65.61% for imazethapyr and 130.0% for 2,4-D. However, when IC50 was calculated by CIPW and CHF-LPME, the CVs of the IC50 values decreased to 23.51% and 36.23% for imazethapyr and 40.21% and 50.93% for 2,4-D, respectively. These results suggested that CIPW and CHF-LPME may be more appropriate than CAC for estimating the phytotoxicity of WAHs.
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Ácido 2,4-Diclorofenoxiacético/toxicidad , Carbón Orgánico , Herbicidas/toxicidad , Ácidos Nicotínicos/toxicidad , Oryza/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Adsorción , Herbicidas/análisis , Herbicidas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Microextracción en Fase Líquida , Ácidos Nicotínicos/análisis , Ácidos Nicotínicos/aislamiento & purificación , Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/aislamiento & purificaciónRESUMEN
Dimethoate, a systemic insecticide, has been used extensively in vegetable production. Insecticide residues in treated vegetables, however, pose a potential risk to consumers. Photocatalytic degradation is a new alternative to managing pesticide residues. In this study, the degradation of dimethoate in Bok choy was investigated under the field conditions using cerium-doped nano titanium dioxide (TiO2/Ce) hydrosol as a photocatalyst. The results show that TiO2/Ce hydrosol can accelerate the degradation of dimethoate in Bok choy. Specifically, the application of TiO2/Ce hydrosol significantly increased the reactive oxygen species (ROS) contents in the treated Bok choy, which speeds up the degradation of dimethoate. Ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS) analysis detected three major degradation products, including omethoate, O,O,S-trimethyl thiophosphorothioate, and 1,2-Bis (acetyl-N-methyl-) methane disulfide. Two potential photodegradation pathways have been proposed based on the intermediate products. To understand the relationship between photodegradation and the molecular structure of target insecticides, we investigated the bond length, Mulliken atomic charge and frontier electron density of dimethoate using ab initio quantum analysis. These results suggest the P = S, P-S and S-C of dimethoate are the initiation sites for the photocatalytic reaction in Bok choy, which is consistent with our empirical data.
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Brassica rapa/química , Cerio/farmacología , Dimetoato/efectos de la radiación , Nanopartículas/efectos de la radiación , Residuos de Plaguicidas/efectos de la radiación , Fotólisis , Titanio/efectos de la radiación , Dimetoato/química , Contaminación de Alimentos , Estructura Molecular , Oxidación-Reducción , Residuos de Plaguicidas/química , Especies Reactivas de Oxígeno , Semiconductores , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
Polymyxa graminis is an obligate parasite and important vector of more than 14 soilborne plant viruses that pose a significant threat to cereal crops in Europe, North America, and Asia. Different ribotypes or formae speciales of P. graminis have been recognized and these may be associated with different cereal hosts or with transmission of different viruses. Two soilborne viruses infecting winter wheat in China have been reported and well studied (Wheat yellow mosaic virus [WYMV, genus Bymovirus] and Chinese wheat mosaic virus [CWMV, genus Furovirus]) but there has been no reported characterization of P. graminis isolates associated with them. In this study, the ribosomal DNA internal transcribed spacer (ITS) regions of P. graminis were examined from 63 wheat samples with apparent virus symptoms obtained from 16 sites within six Chinese provinces. Their associations with soilborne viruses were investigated. Ribotype I (P. graminis f. sp. temperata) and ribotype II (P. graminis f. sp. tepida) were confirmed in winter wheat regions of China for the first time. All 63 wheat root samples were infected with ribotype I of P. graminis and 11 were also infected with ribotype II. There was no obvious association between the ribotypes and infection by either WYMV or CWMV (or double infection). Phylogenetic analysis of the P. graminis ITS1-5.8S-ITS2 sequences revealed that ribotype I in China belongs to previously reported subgroup Ib, whereas ribotype II belongs to IIa. There was considerable sequence variation (pairwise distances from 0.0219 to 0.0319) between Chinese ribotype I isolates of different regions and previously reported ribotype I isolate Ken5 (accession number HE860055.1).
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Virus de Plantas/aislamiento & purificación , Plasmodiophorida/clasificación , Ribotipificación , Triticum/parasitología , Triticum/virología , China , Filogenia , Raíces de Plantas/parasitología , Raíces de Plantas/virología , Microbiología del SueloRESUMEN
RNA silencing is an important innate antiviral defense in plants. Soil-borne plant viruses naturally infect roots via soil-inhabiting vectors, but it is unclear how antiviral RNA silencing responds to virus infection in this particular tissue. In this study, viral small interfering RNA (siRNA) profiles from leaves and roots of wheat plants naturally infected with a soil-borne virus, wheat yellow mosaic virus (WYMV, genus Bymovirus), were analyzed by deep sequencing. WYMV siRNAs were much more abundant in roots than leaves, which was positively correlated with the accumulation of viral RNA. WYMV siRNAs in leaves and roots were predominantly 21- and 22-nt long and equally derived from the positive- and negative-strands of the viral genome. WYMV siRNAs from leaves and roots differed in distribution pattern along the viral genome. Interestingly, compared to siRNAs from leaves (and most other reports), those from roots obviously had a lower A/U bias at the 5'-terminal nucleotide. Moreover, the expression of Dicer-like genes upon WYMV infection were differently regulated between leaves and roots. Our data suggest that RNA silencing in roots may operate differently than in leaves against soil-borne virus invasion.
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The toxicity of ionizable organic compounds to organisms depends on the pH, which therefore affects risk assessments of these compounds. However, there is not a direct chemical method to predict the toxicity of ionizable organic compounds. To determine whether hollow-fiber liquid-phase microextraction (HF-LPME) is applicable for this purpose, a three-phase HF-LPME was used to measure sulfadiazine and estimate its toxicity to Daphnia magna in solutions of different pH. The result indicated that the sulfadiazine concentrations measured by HF-LPME decreased with increasing pH, which is consistent with the decreased toxicity. The concentration immobilize 50% of the daphnids (EC50) in 48 h calculated from nominal concentrations increased from 11.93 to 273.5 mg L-1 as the pH increased from 6.0 to 8.5, and the coefficient of variation (CV) of the EC50 values reached 104.6%. When calculated from the concentrations measured by HF-LPME (pH 12 acceptor phase), the EC50 ranged from 223.4 to 394.6 mg L-1, and the CV decreased to 27.60%, suggesting that the concentrations measured by HF-LPME can be used to estimate the toxicity of sulfadiazine irrespective of the solution pH.
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Técnicas Biosensibles/métodos , Daphnia , Sulfadiazina/análisis , Sulfadiazina/toxicidad , Animales , Concentración de Iones de HidrógenoRESUMEN
Neuroendocrine differentiation (NED) in colorectal cancer is an indistinct phenomenon and may define a new cancer subtype, especially in the poorly differentiated colorectal cancer (PDCRC). The clinical features of PDCRC with NED remain controversial, thus confusing the implementation of individualized treatment. This study included 171 patients who underwent surgery from 2000 to 2011 and had pathology-confirmed PDCRC. Each sample was examined by immunohistochemistry for the biological markers of NED, synaptophysin (Syn), and chromogranin (CgA). Patients with Syn(+) and/or CgA(+) cells were classified as NED(+); otherwise, they were NED(-). Data were collected for patients who were followed up for at least two years. NED(+) staining was present in 71 (41.5%) patients. The median survival time was 36.9 months. No survival differences existed between the NED(-) and NED(+) groups (P > 0.05). However, stage II NED(+) patients had a significantly worse prognosis than NED(-) patients (P = 0.018). For the NED(+) group, the median survival was 38.56 months, and the 5-year survival was 65%. For the NED(-) group, the median survival was 53.18 months, and the 5-year survival was 90%. NED is a common event in primary PDCRC. For stage II PDCRC, NED(+) indicates a poor prognosis.