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Xingkai Lake, located in Heilongjiang Province, is an important fishery and agricultural base and is seriously polluted by agricultural non-point sources. To clarify the residual status of many pesticides in the surface water of Xingkai Lake, 27 types of pesticides, herbicides, and their degradation products were analyzed in rice paddy, drainage, and surface water around Xingkai Lake (China) during the rice heading and maturity periods. The results showed that all 27 types of pesticides, herbicides, and their degradation products were detected during the rice heading period, and the total concentration ranged from 247.97 to 6 094.49 ng·L-1. Additionally, 25 species were detected during the rice maturity period, and the total concentration ranged from 485.36 to 796.23 ng·L-1. In comparison, more pesticides, herbicides, and derived degradation products were detected during the heading period, and their total concentration was higher as well. During the rice heading period, atrazine, simetryn, and paclobutrazol were the main detected pesticides, atrazine and isoprothiolane were the main pesticides detected during the maturity period. The distribution characteristics of pesticides and herbicides in the surface water around Xingkai Lake (China) was similar to that in drainage, so they were probably imported from the drainage and rice paddy. The average risk quotient (RQ) values of atrazine, simetryn, prometryn, butachlor, isoprothiolane, and oxadiazon were higher than 0.1 in drainage and Xingkai Lake (China), which showed a potential risk to aquatic organisms.
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Atrazina , Herbicidas , Residuos de Plaguicidas , Plaguicidas , Tiofenos , Contaminantes Químicos del Agua , Plaguicidas/análisis , Residuos de Plaguicidas/análisis , Lagos , Monitoreo del Ambiente , Agua/química , China , Medición de Riesgo , Contaminantes Químicos del Agua/análisisRESUMEN
Alzheimer's disease(AD), vascular dementia(VD), and traumatic brain injury(TBI) are more common cognitive impairment diseases characterized by high disability and mortality rates, imposing a heavy burden on individuals and their families. Although AD, VD, and TBI have different specific mechanisms, their pathogenesis is closely related to the nucleotide-binding oligome-rization domain-like receptor protein 3(NLRP3). The NLRP3 inflammasome is involved in neuroinflammatory responses, mediating microglial polarization, regulating the reduction of amyloid ß-protein(Aß) deposition, neurofibrillary tangles(NFTs) formation, autophagy regulation, and maintaining brain homeostasis, and synaptic stability, thereby contributing to the development of AD, VD, and TBI. Previous studies have shown that traditional Chinese medicine(TCM) can alleviate neuroinflammation, promote microglial polarization towards the M2 phenotype, reduce Aß deposition and NFTs formation, regulate autophagy, and maintain brain homeostasis by intervening in NLRP3 inflammasome, hence exerting a role in preventing and treating cognitive impairment-related diseases, reducing psychological and economic pressure on patients, and improving their quality of life. Therefore, this article elucidated the role of NLRP3 inflammasome in AD, VS, and TBI, and provided a detailed summary of the latest research results on TCM intervention in NLRP3 inflammasome for the prevention and treatment of these diseases, aiming to inherit the essence of TCM and provide references and foundations for clinical prevention and treatment of cognitive impairment-related diseases with TCM. Meanwhile, this also offers insights and directions for further research in TCM for the prevention and treatment of cognitive impairment-related diseases.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Péptidos beta-Amiloides/metabolismo , Medicina Tradicional China , Calidad de Vida , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/prevención & control , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/prevención & controlRESUMEN
Platinum-based chemotherapy is one of the predominant strategies for treating ovarian cancer (OC), however, platinum resistance greatly influences the therapeutic effect. Circular RNAs (circRNAs) have been found to participate in the pathogenesis of platinum resistance. Our aim was to explore the involvement of circ_0078607 in OC cell cisplatin (DDP) resistance and its potential mechanisms. Circ_0078607, miR-196b-5p, and growth arrest-specific 7 (GAS7) levels were assessed by qPCR. Circ_0078607 stability was assessed by ribonuclease R digestion and actinomycin D treatment. Cell viability of various conic of DDP treatment was measured by CCK-8. The cell proliferation was determined by CCK-8 and colony formation assay. Western blotting was performed for determining GAS7, ABCB1, CyclinD1 and Bcl-2 protein levels. The direct binding between miR-196b-5p and circ_0078607 or GAS7 was validated by dual-luciferase reporter and RIP assay. DDP resistance in vivo was evaluated in nude mice. Immunohistochemistry staining for detecting Ki67 expression in xenograft tumours. Circ_0078607 and GAS7 was down-regulated, but miR-196b-5p was up-regulated in OC samples and DDP-resistant cells. Overexpression of circ_0078607 inhibited DDP resistance, cell growth and induced apoptosis in DDP-resistant OC cells. Mechanistically, circ_0078607 sequestered miR-196b-5p to up-regulate GAS7. MiR-196b-5p mimics reversed circ_0078607 or GAS7 overexpression-mediated enhanced sensitivity. Finally, circ_0078607 improved the sensitivity of DDP in vivo. Circ_0078607 attenuates DDP resistance via miR-196b-5p/GAS7 axis, which highlights the therapeutic potential of circ_0078607 to counter DDP resistance in OC.
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MicroARNs , Proteínas del Tejido Nervioso , Neoplasias Ováricas , Platino (Metal) , ARN Circular , Animales , Femenino , Humanos , Ratones , Proliferación Celular , Cisplatino , Metilación de ADN , Resistencia a Antineoplásicos , Ratones Desnudos , MicroARNs/genética , Proteínas del Tejido Nervioso/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Platino (Metal)/farmacología , ARN Circular/genéticaRESUMEN
Two-dimensional (2D) molybdenum diselenide (MoSe2) as one of the ultrathin transition metal dichalcogenides (TMDs) has attracted considerable attention because of its potential applications in thermoelectric and nano-electronic devices. Here, the thermal conductivity of monolayer MoSe2 and its responses to simulated size and defects are studied by nonequilibrium molecular dynamics simulations. With the increase of sample length, the thermal conductivity of monolayer MoSe2 nanoribbons exhibits an enhancement whereas it is insensitive to the width. At room temperature, the thermal conductivities of monolayer MoSe2 along armchair and zigzag directions are 17.758 and 18.932 W (m K)-1, respectively, which are consistent with previous results. The impact of defects on thermal conductivity has also been studied by varying the concentration of the vacancy from 0.1% to 0.5%. The results show that an increase of the defect concentration will greatly suppress the thermal conductivity. The 0.5% defect concentration with a Mo vacancy can result in a thermal conductivity reduction of â¼43%. Such a study would provide a good insight into the tunable thermal transport for potential applications of not only monolayer MoSe2, but also many other TMDs.
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Objective: Many studies have explored the effects of individual foods or nutrients on fluorosis, but no studies have focused on dietary patterns. This study examined the relationship between dietary patterns and coal-burning fluorosis in Guizhou, China. Methods: This 1:1 matched case-control study was conducted in Zhijin County of Guizhou province with a sample size of 200 cases of fluorosis and 200 age and gender matched controls. Habitual dietary intake was assessed by face-to-face interviews, using a validated 75-item food frequency questionnaire (FFQ) and various covariates using structured questionnaires. The dietary patterns were identified by factor analysis. Results: The factor analysis identified three major dietary patterns which were labeled healthy, easy-to-roast and high protein. After adjusting for various confounding factors, a decreased risk for fluorosis was observed in the highest tertile of the healthy dietary pattern relative to the lowest tertile (OR = 0.47, 95% CI = 0.27-0.84, P-trend = 0.003) and a positive association was observed between the easy-to-roast dietary pattern and fluorosis risk (OR = 2.05, 95% CI = 1.15-3.66), with a significant linear trend (P = 0.017). We did not find an association between fluorosis risk and the high protein dietary pattern. The relationships remained significant when the analyses were stratified by gender and fluorosis subtypes. Conclusion: The healthy dietary pattern may lower coal-burning fluorosis risk; in contrast, the easy-to-roast dietary pattern significantly increases the risk of coal-burning fluorosis.
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Four new acylated triterpene glycosides with aliphatic chains (4-7) as well as five known triterpenoids were isolated from the flower buds of Staphylea bumalda with bioassay guidance. Their structures were determined on the basis of spectral techniques, including IR, 1D and 2D NMR, and HR-APCI-MS. Most compounds (except 8) were isolated from S. bumalda for the first time. Additionally, the neuroprotective effects of 1 and 4-9 on suckling rat primary cultured hippocampal neurons against H2O2-induced injury were evaluated in vitro. The four new triterpenoids (4-7) showed neuroprotective effects, which increased the cell viability to over 74% at different concentrations, which was higher than the negative control (59%), while compounds 1 and 8-9 exhibited cytotoxic activity.
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Glicósidos/farmacología , Hipocampo/efectos de los fármacos , Peróxido de Hidrógeno/antagonistas & inhibidores , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Triterpenos/farmacología , Animales , Flores/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Hipocampo/patología , Peróxido de Hidrógeno/farmacología , Magnoliopsida/química , Neuronas/patología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Triterpenos/química , Triterpenos/aislamiento & purificaciónRESUMEN
Volatile organic compounds (VOCs) in the urban drinking water distribution systems for two coastal cities (S City and L City) in China were analyzed. Health risk assessments of VOCs detected in tap water were performed, and the distribution characteristics of VOCs in the tap water pipe network were also investigated. Among 47 target VOCs, 16 compounds were detected, of which 11 were detected in both S City and L City. Halogenated hydrocarbons were the most commonly detected VOCs, with trihalomethanes (including bromodichloromethane, dibromochloromethane, and bromoform) having the highest detection frequencies (92%-100%). With the exception of bromodichloromethane and dibromochloromethane, the maximum concentrations of detected VOCs in both cities complied with the relevant limits regulated by the standards for drinking water quality (GB 5749-2006). For bromodichloromethane and dibromochloromethane, not only did their concentrations exceed the standard limits of GB 5749-2006 (60 µg·L-1 for bromodichloromethane and 100 µg·L-1 for dibromochloromethane), but their lifetime cancer risks (LCR) were estimated at unacceptable levels (>10-4). Therefore, these two compounds should be given sufficient attention or be classified as priority control pollutants in municipal water supply networks. In addition, the spatial distribution of eight VOCs with high detection frequencies (>90%) in the tap water pipe network of S City was investigated. The concentrations of VOCs (excluding toluene) in this urban drinking water distribution system gradually decreased with increasing distance from the drinking water treatment plant.
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Agua Potable , Compuestos Orgánicos Volátiles/análisis , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua , China , Monitoreo del AmbienteRESUMEN
Porous BiOCl micro-flowers constructed from ultrathin nanosheets with nearly 100% {001} facets exposed were selectively prepared. The exposed {001} facets terminated with a high density of oxygen atoms and are not only favorable for the adsorption of the cationic dye RhB but also can accumulate the photogenerated electrons injected from excited RhB. These electrons can be captured by O(2) and transformed to reactive oxygen species, which possess a strong photooxidative ability to degrade the dye pollutants directly and easily. Therefore, the resultant BiOCl photocatalysts exhibit superior activity for indirect dye photosensitization degradation under visible light, with a rapid degradation rate and high photostability.
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Bismuto/química , Nanoestructuras/química , Oxidación-Reducción , Fotólisis , Porosidad , Especies Reactivas de Oxígeno/química , Rodaminas/químicaRESUMEN
Direct fabrication of core-shell or yolk-shell functional nanomaterials via a facile template-free method remains a challenge. In this work, we present a novel approach that involves straightforward chemical transformation and thermal treatment of the infinite coordination polymer particles to obtain composition-tunable CeO(2) yolk-shell structures. Uniform CeO(2) yolk-shell hollow spheres with a high surface area are promising support materials for tiny gold nanoparticles (ca. 4 nm), forming Au-CeO(2) nanocomposites which exhibit a remarkable catalytic activity and high stability for the reduction of p-nitrophenol. A possible mechanism for the formation of CeO(2) yolk-shell microspheres is also proposed.
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Cerio/química , Oro/química , Nanopartículas del Metal/química , Nitrofenoles/química , Catálisis , Nanocompuestos/química , Oxidación-Reducción , Polímeros/química , Propiedades de SuperficieRESUMEN
Visible light photocatalytic H(2) production from water splitting is of great significance for its potential applications in converting solar energy into chemical energy. In this study, a series of Zn(1-x)Cd(x)S solid solutions with a nanoporous structure were successfully synthesized via a facile template-free method at room temperature. The obtained solid solutions were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS) and N(2) adsorption-desorption analysis. The solid solutions show efficient photocatalytic activity for H(2) evolution from aqueous solutions containing sacrificial reagents S(2-) and SO(3)(2-) under visible-light irradiation without a Pt cocatalyst, and loading of the Pt cocatalyst further improves the visible-light photocatalytic activity. The optimal photocatalyst with x = 0.20 prepared at pH = 7.3 displays the highest activity for H(2) evolution. The bare and 0.25 wt% Pt loaded Zn(0.80)Cd(0.20)S nanoparticles exhibit a high H(2) evolution rate of 193 µmol h(-1) and 458 µmol h(-1) under visible-light irradiation (λ ≥ 420 nm), respectively. In addition, the bare and 0.25 wt% Pt loaded Zn(0.80)Cd(0.20)S catalysts show a high H(2) evolution rate of 252 and 640 µmol h(-1) under simulated solar light irradiation, respectively. Moreover, the Zn(0.80)Cd(0.20)S catalyst displays a high photocatalytic stability for H(2) evolution under long-term light irradiation. The incorporation of Cd in the solid solution leads to the visible light absorption, and the high content of Zn in the solid solution results in a relatively negative conduction band, a modulated band gap and a rather wide valence bandwidth, which are responsible for the excellent photocatalytic performance of H(2) production and for the high photostability.
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Compuestos de Cadmio/química , Cristalización/métodos , Hidrógeno/química , Nanoestructuras/química , Sulfuros/química , Compuestos de Zinc/química , Compuestos de Cadmio/efectos de la radiación , Catálisis , Hidrógeno/aislamiento & purificación , Luz , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Nanoestructuras/efectos de la radiación , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Soluciones/química , Sulfuros/efectos de la radiación , Propiedades de Superficie , Temperatura , Compuestos de Zinc/efectos de la radiaciónRESUMEN
N-doped TiO(2) nanoparticles modified with carbon (denoted N-TiO(2)/C) were successfully prepared by a facile one-pot hydrothermal treatment in the presence of L-lysine, which acts as a ligand to control the nanocrystal growth and as a source of nitrogen and carbon. As-prepared nanocomposites were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), electron paramagnetic resonance (EPR) spectra, and N(2) adsorption-desorption analysis. The photocatalytic activities of the as-prepared photocatalysts were measured by the degradation of methyl orange (MO) under visible light irradiation at λ≥ 400 nm. The results show that N-TiO(2)/C nanocomposites increase absorption in the visible light region and exhibit a higher photocatalytic activity than pure TiO(2), commercial P25 and previously reported N-doped TiO(2) photocatalysts. We have demonstrated that the nitrogen was doped into the lattice and the carbon species were modified on the surface of the photocatalysts. N-doping narrows the band gap and C-modification enhances the visible light harvesting and accelerates the separation of the photo-generated electrons and holes. As a consequence, the photocatalytic activity is significantly improved. The molar ratio of L-lysine/TiCl(4) and the pH of the hydrothermal reaction solution are important factors affecting the photocatalytic activity of the N-TiO(2)/C; the optimum molar ratio of L-lysine/TiCl(4) is 8 and the optimum pH is ca. 4, at which the catalyst exhibits the highest reactivity. Our findings demonstrate that the as-obtained N-TiO(2)/C photocatalyst is a better and more promising candidate than well studied N-doped TiO(2) alternatives as visible light photocatalysts for potential applications in environmental purification.
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Compuestos Azo/química , Carbono/química , Nanoestructuras/química , Nanoestructuras/efectos de la radiación , Titanio/química , Compuestos Azo/efectos de la radiación , Catálisis , Calor , Luz , Sustancias Macromoleculares/química , Sustancias Macromoleculares/efectos de la radiación , Ensayo de Materiales , Conformación Molecular/efectos de la radiación , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Propiedades de Superficie/efectos de la radiación , Agua/químicaRESUMEN
A simple hard template method has been developed to prepare uniform matchstick-like PbS nanocrystals. The approach combines functionalization of the mesoporous walls and channel surface with thioether groups, adsorption of Pb2+, and heating in an N2 atmosphere at high temperature. The structure, morphology and composition of the nanocrystals have been characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), energy dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The optical properties of the matchstick-like PbS nanocrystals have been systematically investigated by Raman spectroscopy, UV-visible absorption spectroscopy (UV-vis), and photoluminescence spectroscopy (PL). These results demonstrate that these matchstick-like PbS nanocrystals are single crystals and possess novel optical properties, suggesting that they may have many potential applications. A large blue shift is observed in the photoluminescence spectrum, and this clearly shows the quantum size effects of the matchstick-like PbS . Furthermore, a growth mechanism of the PbS heteronanostructure is proposed.
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Cristalización/métodos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Compuestos Orgánicos/química , Compuestos de Selenio/síntesis química , Dióxido de Silicio/química , Plomo , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Porosidad , Propiedades de SuperficieRESUMEN
Many human papillomavirus (HPV)-positive high-grade lesions and cancers of the uterine cervix harbor integrated HPV genomes expressing the E6 and E7 oncogenes from chimeric virus-cell mRNAs, but less is known about HPV integration in head and neck cancer (HNC). Here we compared viral DNA status and E6-E7 mRNA sequences in HPV-16-positive HNC tumors to those in independent human keratinocyte cell clones derived from primary tonsillar or foreskin epithelia immortalized with HPV-16 genomes. Three of nine HNC tumors and epithelial clones containing unintegrated HPV-16 genomes expressed mRNAs spliced from HPV-16 SD880 to SA3358 and terminating at the viral early gene p(A) signal. In contrast, most integrated HPV genomes in six HNCs and a set of 31 keratinocyte clones expressed HPV-16 major early promoter (MEP)-initiated mRNAs spliced from viral SD880 directly to diverse cellular sequences, with a minority spliced to SA3358 followed by a cellular DNA junction. Sequence analysis of chimeric virus-cell mRNAs from HNC tumors and keratinocyte clones identified viral integration sites in a variety of chromosomes, with some located in or near growth control genes, including the c-myc protooncogene and the gene encoding FAP-1 phosphatase. Taken together, these findings support the hypothesis that HPV integration in cancers is a stochastic process resulting in clonal selection of aggressively expanding cells with altered gene expression of integrated HPV genomes and potential perturbations of cellular genes at or near viral integration sites. Furthermore, our results demonstrate that this selection also takes place and can be studied in primary human keratinocytes in culture.
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Neoplasias de Cabeza y Cuello/virología , Papillomavirus Humano 16/genética , Queratinocitos/virología , ARN Mensajero/metabolismo , Recombinación Genética , Integración Viral , Transformación Celular Viral , Células Cultivadas , Células Clonales/virología , Femenino , Genoma Viral , Papillomavirus Humano 16/metabolismo , Humanos , Queratinocitos/metabolismo , Masculino , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , ARN Mensajero/genética , ARN Viral/genética , ARN Viral/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Neoplasias del Cuello Uterino/virologíaRESUMEN
To investigate the pollution levels, occurrence and distribution of estrogens, six estrogens in the surface sediments of Wenyuhe River were analyzed quantitatively by GC/MS following ultrasonicated extraction including diethylstilbestrol (DES), estrone (E1), beta-estradiol(E2), 17alpha-ethynylestradiol(EE2), estriol(E3), and beta-estradiol 17-valerate (EV). Six estrogen concentrations ranged from 0.39-36.6 ng/g and the mean concentration was 10.2 ng/g. E1 and E2 were detected in all samples while other four estrogens were only detected in a few samples, and the concentrations of El was higher than those of E2 in all samples. There were significant correlation relationships between the concentrations of six estrogens and the concentrations of total organic carbon (TOC), total phosphorus (TP) and total nitrogen (TN) in sediments. Considering also the characteristics of the sampling locations and pollution sources, six estrogens should come from wastewater discharges along the river and the contaminated tributaries. The contents of estrogens in this area are medium or slightly higher level compared with other areas abroad.
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Disruptores Endocrinos/análisis , Estrógenos/análisis , Sedimentos Geológicos/análisis , Ríos , Contaminantes Químicos del Agua/análisis , China , Estradiol/análisis , Estrona/análisis , Sedimentos Geológicos/químicaRESUMEN
A new method to assess phosphorus bioavailability in the sediments and soils was developed by using a homemade iron oxide/ cellulose acetate membrane(FeO/CAM). The results show that the amount of bioavailable phosphorus(FeO-P) desorbed from the sediment and soil increased with the shaking time,and FeO-P desorption would come to equilibrium after 16 ot 20h. With the increase of the ratio between soil mass and water volume, the quantity of the desorbed FeO-P would decrease and then went planar after 20 to 30g/L. The quantity of the desorbed FeO-P had no significant difference between the FeO/CAMs of 20 to 30cm2. The dynamics of FeO-P desorption from the sediments and soils would be accelerated by appropriately increasing the shaking frequency. In short, FeO/ CAMs overcome many disadvantages of iron oxide impregnated filter paper and are easy to be commercialized; therefore it may have a better future in the application to assessing phosphorus hioavailability in the sediments and soils.
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Eucariontes/metabolismo , Sedimentos Geológicos/análisis , Fósforo/metabolismo , Suelo/análisis , Disponibilidad Biológica , Celulosa/análogos & derivados , Celulosa/química , Compuestos Férricos/química , Membranas Artificiales , Fósforo/químicaRESUMEN
Phosphorus release from the sediment is generally an important factor for lake eutrophication. We have investigated phosphorus forms in surface sediments from Lake Taihu and Lake Chaohu by a chemical extraction method. The results showed that the concentrations of Fe/Al-bound phosphorus (Fe/Al-P) and organic phosphorus (Org-P) had significant correlations with those of amorphous Fe/Al oxides and organic matter in the sediments. Furthermore, Ca-bound phosphorus (Ca-P) concentrations were well related to total organic carbon (TOC) concentrations. The results also indicated that higher pH weakened the association of phosphates with the Fe/Al hydroxides and then resulted in Fe/Al-P release. The increase of pH was companied with autogenetic progresses of calcium carbonate and then elevated Ca-P concentrations in the sediments. In conclusion, external P loadings determine spatial distribution of P fractions, especially Fe/Al-P and Org-P, and partially contribute to additional Ca-P fractions in these highly human-disturbed lakes. The pH-induced phosphorus mobility in the sediments is very important for these lakes.
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Sedimentos Geológicos/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Aluminio/química , Calcio/química , China , Monitoreo del Ambiente , Eutrofización , Agua Dulce , Concentración de Iones de Hidrógeno , Hierro/química , Fósforo/químicaRESUMEN
BACKGROUND: Human papillomavirus (HPV) has been associated with the development of head and neck cancers. In this study, we investigated whether the risk factors for head and neck cancer in relation to HPV infection are different from those in the absence of HPV infection and whether HPV detected in oral exfoliated cells is an independent predictor of head and neck cancer risk. METHODS: We conducted a case-control study in 201 head and neck cancer case patients and 333 control subjects, frequency matched for age and sex. Oral exfoliated cells and tumor tissue were evaluated for HPV using polymerase chain reaction and DNA sequencing to type HPV. Logistic regression was used to calculate odds ratios (ORs) for head and neck cancer with HPV infection and 95% confidence intervals (CIs), adjusted for age, tobacco use, and alcohol consumption. RESULTS: Oncogenic, or high-risk (HR), HPV types were detected in oral cells from 22.9% of case patients and 10.8% of control subjects. HPV16 was the most frequently detected type (19% versus 10% of case patients and control subjects, respectively). After adjusting for age, tobacco use, and alcohol consumption, the risk of head and neck cancer was statistically significantly greater in individuals with HPV-HR types (adjusted OR = 2.6, 95% CI = 1.5 to 4.2) but not in individuals with nononcogenic HPV types (adjusted OR = 0.8, 95% CI = 0.4 to 1.7) compared with HPV-negative individuals. Compared with individuals who were HPV-negative and did not use alcohol or tobacco, there was a statistically significant synergistic effect between detection of HPV-HR and heavy alcohol consumption (OR = 18.8, 95% CI = 5.1 to 69.5) but an additive effect between detection of HPV-HR and tobacco use (OR = 5.5, 95% CI = 2.1 to 14.1). HPV-HR types detected in oral exfoliated cells were predictive of HPV-HR types in tumor tissue. CONCLUSION: Infection of oral exfoliated cells with HPV-HR types is a risk factor for head and neck cancer, independent of alcohol and tobacco use, and acts synergistically with alcohol consumption. HPV testing of an oral rinse may be predictive of an HPV-related head and neck cancer.