RESUMEN
Significant progress has been made previously in the research and development of graphene oxide (GO) membranes for water purification, but their biofouling behavior remains poorly understood. In this study, we investigated the biofilm formation and biofouling of GO membranes with different surface microstructures in the context of filtering natural surface water and for an extended operation period (110 days). The results showed that the relatively hydrophilic and smooth Fe(OH)3/GO membrane shaped a thin and spatially heterogeneous biofilm with high stable flux. However, the ability to simultaneously mitigate biofilm formation and reduce biofouling was not observed in the weakly hydrophilic and wrinkled Fe/GO and H-Fe(OH)3/GO membranes. Microbial analyses revealed that the hydrophilicity and roughness distinguished the bacterial communities and metabolic functions. The organic matter-degrading and predatory bacteria were more adapted to hydrophilic and smooth GO surfaces. These functional taxa were involved in the degradation of extracellular polymeric substances (EPS), and improved biofilm heterogeneity. In contrast, the weakly hydrophilic and wrinkled GO surfaces had reduced biodiversity, while unexpectedly boosting the proliferation of EPS-secreting bacteria, resulting in increased biofilm formation and aggravated biofouling. Moreover, all GO membranes achieved sustainable water purification during the entire operating period.
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Biopelículas , Incrustaciones Biológicas , Grafito , Purificación del Agua , Grafito/química , Membranas Artificiales , Óxidos/químicaRESUMEN
The established benefits of ozone on microbial pathogen inactivation, natural organic matter degradation, and inorganic/organic contaminant oxidation have favored its application in drinking water treatment. However, viable bacteria are still present after the ozonation of raw water, bringing a potential risk to membrane filtration systems in terms of biofilm accumulation and fouling. In this study, we shed light on the role of the specific ozone dose (0.5 mg-O3/mg-C) in biofilm accumulation during long-term membrane ultrafiltration. Results demonstrated that ozonation transformed the molecular structure of influent dissolved organic matter (DOM), producing fractions that were highly bioavailable at a specific ozone dose of 0.5, which was inferred to be a turning point. With the increase of the specific ozone dose, the biofilm microbial consortium was substantially shifted, demonstrating a decrease in richness and diversity. Unexpectedly, the opportunistic pathogen Legionella was stimulated and occurred in approximately 40% relative abundance at the higher specific ozone dose of 1. Accordingly, the membrane filtration system with a specific ozone dose of 0.5 presented a lower biofilm thickness, a weaker fluorescence intensity, smaller concentrations of polysaccharides and proteins, and a lower Raman activity, leading to a lower hydraulic resistance, compared to that with a specific ozone dose of 1. Our findings highlight the interaction mechanism between molecular-level DOM composition, biofilm microbial consortium, and membrane filtration performance, which provides an in-depth understanding of the impact of ozonation on biofilm accumulation.
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Ozono , Purificación del Agua , Membranas Artificiales , Ultrafiltración , BiopelículasRESUMEN
Terrestrial dissolved organic matter (DOM) is critical to global carbon and nutrient cycling, climate change, and human health. However, how the spatial and compositional differences of soil DOM affect its dynamics and fate in water during the carbon cycle is largely unclear. Herein, the biodegradation of DOM from 14 spatially distributed grassland soils in China with diverse organic composition was investigated by 165 days of incubation experiments. The results showed that although the high humified fraction (high-HS) regions were featured by high humic-like fractions of 4-25 kDa molecular weight, especially the abundant condensed aromatics and tannins, they unexpectedly displayed greater DOM degradation during 45-165 days. In contrast, the unique proteinaceous and 25-100 kDa fractions enriched in the low humified fraction (low-HS) regions were drastically depleted and improved the decay of bulk DOM but only during 0-45 days. Together, DOM from the high-HS regions would cause lower CO2 outgassing to the atmosphere but higher organic loads for drinking water production in the short term than that from the low-HS regions. However, this would be reversed for the two regions during the long-term transformation processes. These findings highlight the importance of spatial and temporal variability of DOM biogeochemistry to mitigate the negative impacts of grassland soil DOM on climate, waters, and humans.
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Materia Orgánica Disuelta , Suelo , Humanos , Pradera , Carbono , Agua , ChinaRESUMEN
PURPOSE OF REVIEW: Intracerebral hemorrhage (ICH) is the most devastating type of stroke, causing widespread disability and mortality. Unfortunately, the acute care of ICH has lagged behind that of ischemic stroke. There is an increasing body of evidence supporting the importance of early interventions including aggressive control of blood pressure and reversal of anticoagulation in the initial minutes to hours of presentation. This review highlights scientific evidence behind a new paradigm to care for these patients called Code-ICH. RECENT FINDINGS: While numerous trials aimed at decreasing hematoma expansion through single interventions had failed to show statistically significant effects on primary outcomes, time-sensitive, multifaceted, bundled care approaches have recently shown substantial promise in improving functional outcomes in patients with ICH. The concept of Code-ICH can serve as a structural platform for the practice of acute care neurology to continuously measure its performance, reflect on best practices, advance care, and address disparities.
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Hemorragia Cerebral , Humanos , Hemorragia Cerebral/terapia , Servicios Médicos de Urgencia/métodos , Accidente Cerebrovascular/terapiaRESUMEN
Landfill leachate properties contain important information and can be a unique indicator for the chemical and biochemical activities in landfills. In the recent decade, more landfills are experiencing elevated temperature, causing an imbalance in the decomposition of solid waste and affecting the properties of the landfill leachate. This study analyzes the properties of leachate from two landfills that were experiencing elevated temperature (ETLFs), samples were collected from both elevated temperature impacted and non-impacted areas in each landfill. The accumulation of volatile fatty acids (VFA) in leachates from elevated temperature impacted areas of both landfill sites revealed that methanogenesis was inhibited by the elevated temperature, which was further confirmed by the more acidic pH, higher H/C elemental ratio, and lower degree of aromaticity of the elevated temperature impacted leachates. Also, carbohydrates depletion indicated possible enhancement of hydrolysis and acidogenesis by elevated temperature, which was supported by compositional comparison of isolated acidic species by negative-ion electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICRMS) at 21 T derived from both elevated temperature impacted and non-impacted areas in the same landfill site. Furthermore, leachate organics fractionation showed that leachates not impacted by elevated temperature contain less hydrophilic fraction and more humic fraction than elevated temperature-impacted leachates for both ETLFs.
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Eliminación de Residuos , Contaminantes Químicos del Agua , Eliminación de Residuos/métodos , Contaminantes Químicos del Agua/química , Temperatura , Residuos Sólidos/análisis , Instalaciones de Eliminación de Residuos , Hidrógeno/análisisRESUMEN
The biodegradation in the middle and downstream of slow-rate biological activated carbon (BAC) is limited by insufficient dissolved oxygen (DO) concentrations. In this study, a bubbleless aerated BAC (termed ABAC) process was developed by installing a hollow fiber membrane (HFM) module within a BAC filter to continuously provide aeration throughout the BAC system. The BAC filter without an HFM was termed NBAC. The laboratory-scale ABAC and NBAC systems operated continuously for 426 days using secondary sewage effluent as an influent. The DO concentrations for NBAC and ABAC were 0.78 ± 0.27 and 4.31 ± 0.44 mg/L, respectively, with the latter providing the ABAC with greater electron acceptors for biodegradation and a microbial community with better biodegradation and metabolism capacity. The biofilms in ABAC secreted 47.3% less EPS and exhibited greater electron transfer capacity than those in NBAC, resulting in enhanced contaminant degradation efficiency and long-term stability. The extra organic matter removed by ABAC included refractory substances with a low elemental ratio of oxygen to carbon (O/C) and a high elemental ratio of hydrogen to carbon (H/C). The proposed ABAC filter provides a valuable, practical example of how to modify the BAC technology to shape the microbial community, and its activity, by optimizing the ambient atmosphere.
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Contaminantes Químicos del Agua , Purificación del Agua , Filtración/métodos , Carbón Orgánico , Aguas del Alcantarillado , Biodegradación Ambiental , Biopelículas , Purificación del Agua/métodos , Contaminantes Químicos del Agua/análisisRESUMEN
In situ Fe(III) coprecipitation from Fe2+ oxidation is a widespread phenomenon in natural environments and water treatment processes. Studies have shown the superiority of in situ Fe(III) (formed by in situ oxidation of a Fe(II) coagulant) over ex situ Fe(III) (using a Fe(III) coagulant directly) in coagulation, but the reasons remain unclear due to the uncertain nature of amorphous structures. Here, we utilized an in situ Fe(III) coagulation process, oxidizing the Fe(II) coagulant by potassium permanganate (KMnO4), to treat phosphate-containing surface water and analyzed differences between in situ and ex situ Fe(III) coagulation in phosphate removal, dissolved organic matter (DOM) removal, and floc growth. Compared to ex situ Fe(III), flocs formed by the natural oxidizing Fe2+ coagulant exhibited more effective phosphate removal. Furthermore, in situ Fe(III) formed through accelerated oxidation by KMnO4 demonstrated improved flocculation behavior and enhanced removal of specific types of DOM by forming a more stable structure while still maintaining effective phosphate removal. Fe K-edge extended X-ray absorption fine structure spectra (EXAFS) of the flocs explained their differences. A short-range ordered strengite-like structure (corner-linked PO4 tetrahedra to FeO6 octahedra) was the key to more effective phosphorus removal of in situ Fe(III) than ex situ Fe(III) and was well preserved when KMnO4 accelerated in situ Fe(III) formation. Conversely, KMnO4 significantly inhibited the edge and corner coordination between FeO6 octahedra and altered the floc-chain-forming behavior by accelerating hydrolysis, resulting in a more dispersed monomeric structure than ex situ Fe(III). This research provides an explanation for the superiority of in situ Fe(III) in phosphorus removal and highlights the importance of atomic-level structural differences between ex situ and in situ Fe(III) coprecipitates in water treatment.
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Compuestos Férricos , Purificación del Agua , Compuestos Férricos/química , Materia Orgánica Disuelta , Fosfatos , Oxidación-Reducción , Compuestos Ferrosos/química , Fósforo , Purificación del Agua/métodosRESUMEN
Denitrification-driven Fe(II) oxidation is an important microbial metabolism that connects iron and nitrogen cycling in the environment. The formation of Fe(III) minerals in the periplasmic space has a significant effect on microbial metabolism and electron transfer, but direct evidence of iron ions entering the periplasm and resulting in periplasmic mineral precipitation and electron conduction properties has yet to be conclusively determined. Here, we investigated the pathways and amounts of iron, with different valence states and morphologies, entering the periplasmic space of the denitrifier Pseudomonas sp. JM-7 (P. JM-7), and the possible effects on the electron transfer and the denitrifying ability. When consistently provided with Fe(II) ions (from siderite (FeCO3)), the dissolved Fe(II) ions entered the periplasmic space and were oxidized to Fe(III), leading to the formation of a 25 nm thick crystalline goethite crust, which functioned as a semiconductor, accelerating the transfer of electrons from the intracellular to the extracellular matrix. This consequently doubled the denitrification rate and increased the electron transport capacity by 4-30 times (0.015-0.04 µA). However, as the Fe(II) concentration further increased to above 4 mM, the Fe(II) ions tended to preferentially nucleate, oxidize, and crystallize on the outer surface of P. JM-7, leading to the formation of a densely crystallized goethite layer, which significantly slowed down the metabolism of P. JM-7. In contrast to the Fe(II) conditions, regardless of the initial concentration of Fe(III), it was challenging for Fe(III) ions to form goethite in the periplasmic space. This work has shed light on the likely effects of iron on environmental microorganisms, improved our understanding of globally significant iron and nitrogen geochemical cycles in water, and expanded our ability to study and control these important processes.
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Compuestos Férricos , Compuestos de Hierro , Periplasma/metabolismo , Agua , Desnitrificación , Compuestos de Hierro/química , Compuestos de Hierro/metabolismo , Minerales/química , Hierro/química , Oxidación-Reducción , Compuestos Ferrosos/química , Compuestos Ferrosos/metabolismo , Nitrógeno/metabolismoRESUMEN
A biofilm has a significant effect on water treatment processes. Currently, there is a lack of knowledge about the effect of temperature on the biofilm structure in water treatment processes. In this study, a gravity-driven membrane ultrafiltration system was operated with river feedwater at two temperatures ("low", 4 °C; "high", 25 °C) to explore the biofilm structure and transformation mechanism. The results showed that the difference in dissolved oxygen concentration might be one of the main factors regulating the structural components of the biofilm. A denser biofilm formation and reduced flux were observed at the lower temperature. The linoleic acid metabolism was significantly inhibited at low temperature, resulting in enhanced pyrimidine metabolism by Na+ accumulation. In addition, the biofilm at low temperature had a higher proportion of the metabolites of lipids and lipid-like molecules (11.25%), organic acids and derivatives (10.83%), nucleosides, nucleotides, and analogues (7.083%), and organoheterocyclic compounds (6.66%). These small molecules secrete more polysaccharides having CâO and OâC-O functional groups, which intensified the resistance of the biofilm. Furthermore, the upregulation pathway of pyrimidine metabolism also increased the risk of urea accumulation at low temperature. Limnohabitans, Deinococcus, Diaphorobacter, Flavobacterium, and Pseudomonas were identified as the principal microorganisms involved in this metabolic transformation.
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Membranas Artificiales , Microbiota , Biopelículas , Metabolómica , Pirimidinas , TemperaturaRESUMEN
The oxidation-precipitation process of Fe(II) is ubiquitous in the environment and critically affects the fate of contaminants and nutrients in natural systems where Fe(II) is present. Here, we explored the effect of H2O2 concentration on the structure of precipitates formed by Fe(II) oxidation and compared the precipitates to those formed by Fe(III) hydrolysis. Additionally, the phosphate retention under different H2O2 concentrations was evaluated. XRD, TEM, PDA, XPS, and UV-visible absorbance spectroscopy were used to characterize the structure of the formed precipitates; UV-visible absorbance spectroscopy was also used to determine the residual phosphate and Fe(II) in solution. It was found that the predominant precipitates in Fe(II) solution changed from planar-shaped crystalline lepidocrocite (γ-FeOOH) to poor short-range order (poorly crystalline) spherical-shaped hydrous ferric oxide (HFO) with increasing H2O2 concentrations. Although the HFO precipitates formed from Fe(II) resembled those formed from Fe(III) hydrolysis, the former was larger and had clearer lattice fringes. During the formation of γ-FeOOH, both Fe(II)-Fe(III) complexes and ligand-to-metal charge transfer processes were observed, and it was found that Fe(II) was present in the planar-shaped precipitates. Fe(II) might be present in the interior of precipitates as Fe(OH)2, which could serve as a nucleus for the epitaxial growth of γ-FeOOH. In addition, the extent of phosphate retention increased with the H2O2 concentration, indicating the increased reactivity of formed precipitates with H2O2 concentration. More phosphate was retained via coprecipitation with Fe than adsorption on the preformed Fe precipitates due to the incorporation of phosphate within the structure of the formed Fe hydroxyphosphate via coprecipitation.
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Compuestos Férricos , Fosfatos , Compuestos Férricos/química , Compuestos Ferrosos , Peróxido de Hidrógeno , Oxidación-Reducción , Fosfatos/químicaRESUMEN
Most coagulation studies focus on pollutant removal or floc separation efficiency. However, to understand the mechanism of coagulation, it is necessary to explore the behavior of coagulation in terms of the interactions among the functional groups on the surface of the metal hydrolysis precipitates during the hydrolysis process. In this study, for the first time, aluminum sulfate (alum) was used to investigate such interactions over the whole process sequence of hydrolysis, coagulation, and crystallization with, and without (as a control), the presence of specific low molecular weight (LMW) (molecular weight < 1000 Da) organic compounds with different chemical bonds. It was observed that primary nanoparticles (NPs) of around 10 nm size were produced during the hydrolysis of alum. The presence of organic compounds was found to influence the coagulation performance by affecting the metal hydrolysis and the properties of the nanoparticles. At pH 7, ethylenediaminetetraacetic acid disodium salt (EDTA) delayed the time when the particles start to aggregate but increased the maximum size of the flocs, while citric acid caused the crystallization of amorphous hydrates and inhibited the coagulation performance. In contrast, glucose, benzoic acid (BEN), and tris(hydroxymethyl)aminomethane (THMAM) had no significant effect on the coagulation performance. Therefore, LMW organics can bond to the hydrolysis products of metal ions through key functional groups, such as carboxyl groups, and then affect the coagulation process. The experimental results show that the presence of LMW organics can change the surface properties and degree of crystallization of the primary NPs, thereby affecting the performance of coagulation.
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Nanopartículas , Purificación del Agua , Compuestos de Alumbre , Cristalización , Floculación , HidrólisisRESUMEN
The presence of biopolymers in surface waters and their significance for potable water supply have received little attention previously owing to their low concentrations. In this paper, we present the results of an extensive study that has investigated the role and benefits of biopolymers during the purification of surface water with reference to their specific biological and physico-chemical properties. Using samples collected from two representative surface waters in China and the United Kingdom, macromolecular biopolymers were separated and concentrated for subsequent investigation of their role in coagulation, metal ion adsorption, and membrane separation. Our results show that biopolymers significantly improve the antifouling capability of membrane nanofiltration, in combination with the enhanced conventional coagulation performance and additional security against several unhealthy metal pollutants (e.g., Fe, Al, and Cr). We believe this is the first study that reveals the versatile benefits and the fate of natural biopolymers in surface water purification processes.
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Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Biopolímeros , China , Reino Unido , Contaminantes Químicos del Agua/análisis , Abastecimiento de AguaRESUMEN
Structure properties of flocs (size, fractal dimension (Df), etc.) have a high impact on coagulation efficiency. In this work, the influences of three different additives (ferric salt (Fe), phosphate (P), and citric acid (CA)) on coagulation process/efficiency were investigated. Results showed that a small amount of extra Fe can facilitate the growth of Al flocs by providing more 'active sites'. Although zeta potential and Df showed a limited change, the average floc size increased apparently and the increment was more obvious when Fe was added after the formation of the flocs. In contrast, P addition during the rapid mixing period will decrease the final average floc size, while the influence is less significant when P was added after the growth of the flocs. In terms of CA, a more striking negative effect on the growth ability of the flocs was observed compared to P. The strong complexing/coordination interactions between CA and aluminum hydroxide is the main reason behind the influence. CA also significantly decreased the Df value of the flocs compared to P, and Df showed a comparatively higher decrease when P or CA was added during the rapid mixing stage compared to the addition after the flocs formation. These results indicated that the addition of CA or P during the rapid mixing stage 'inactivated' or occupied more 'active sites' on the preliminarily formed Al NPs during the hydrolysis process, and therefore presented stronger impact on the morphology/size of the formed flocs.
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Purificación del Agua , Hidróxido de Aluminio , Compuestos Férricos , Floculación , FractalesRESUMEN
Coagulation and precipitation is a widely applied method to remove F- from wastewater. In this work, the effect of coagulation on the removal of F- and organic matter from coking wastewater was studied using AlCl3 and FeCl3 as compound coagulants. The removal rates of F- and organic matter under different coagulant doses and pH conditions were investigated. The results show that the highest removal rates of F- by AlCl3 and FeCl3 are 94.4% and 25.4%, respectively; when the dosage is 10 mmol/L, the TOC removal rates of FeCl3 and AlCl3 reach 20.4% and 34.7%, respectively. Therefore, the removal rate of F- by AlCl3 is higher than that of FeCl3, but the removal rate of organic matter by FeCl3 is relatively higher. The addition of Ca2+ can promote the removal of F-, but the removal rate of organic matter decreases. In addition, by investigating the effects of different pH and Fe-Al ratio on the removal rate, the removal effect of adding FeCl3 and AlCl3 at the same time was discussed. The results show that the most suitable working condition for the removal of organic matter and F- is that the pH is 6.5 and the molar ratio of Al/Fe is 8:2. Overall, the removal mechanism of F- and organic matter in coking wastewater by FeCl3 and AlCl3 was explored in this study. The experimental results can provide reference for the advanced treatment of coking wastewater.
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Coque , Purificación del Agua , Aguas ResidualesRESUMEN
We conducted a prospective, multicenter, randomized, controlled clinical trial to compare the efficacy and safety of high-dose dexamethasone (HD-DXM) plus recombinant human thrombopoietin (rhTPO), vs HD-DXM alone in newly diagnosed adult immune thrombocytopenia (ITP) patients. Enrolled patients were randomly assigned to receive DXM plus rhTPO or DXM monotherapy. Another 4-day course of DXM was repeated if response was not achieved by day 10 in both arms. One hundred patients in the HD-DXM plus rhTPO arm and 96 patients in the HD-DXM monotherapy arm were included in the full analysis set. So, HD-DXM plus rhTPO resulted in a higher incidence of initial response (89.0% vs 66.7%, P < .001) and complete response (CR, 75.0% vs 42.7%, P < .001) compared with HD-DXM monotherapy. Response rate at 6 months was also higher in the HD-DXM plus rhTPO arm than that in the HD-DXM monotherapy arm (51.0% vs 36.5%, P = .02; sustained CR: 46.0% vs 32.3%, P = .043). Throughout the follow-up period, the overall duration of response was greater in the HD-DXM plus rhTPO arm compared to the HD-DXM monotherapy arm (P = .04), as estimated by the Kaplan-Meier analysis. The study drugs were generally well tolerated. In conclusion, the combination of HD-DXM with rhTPO significantly improved the initial response and yielded favorable SR in newly diagnosed ITP patients, thus could be further validated as a frontline treatment for ITP. This study is registered as clinicaltrials.gov identifier: NCT01734044.
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Dexametasona/administración & dosificación , Púrpura Trombocitopénica Idiopática , Trombopoyetina/administración & dosificación , Adulto , Anciano , Dexametasona/efectos adversos , Supervivencia sin Enfermedad , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Púrpura Trombocitopénica Idiopática/mortalidad , Tasa de Supervivencia , Trombopoyetina/efectos adversosRESUMEN
We conducted a prospective, multicenter study to evaluate the efficacy and safety of low-dose decitabine in adult patients with refractory immune thrombocytopenia. Adult patients who did not respond to, did not tolerate, or were unwilling to undergo splenectomy, with either a baseline platelet count less than 30 × 109 /L or the presence of bleeding symptoms and further need of ITP-specific treatments, were enrolled. Patients received decitabine at 3.5 mg/m2 intravenously for three consecutive days per cycle, for three cycles with a four-week interval between cycles. All patients were assessed every week during the first 12 weeks and at four-week intervals thereafter. We screened 49 patients for eligibility. Four patients were excluded and 45 received decitabine. At the end of decitabine treatment, complete response was achieved in eight patients (17.78%), and partial response was achieved in 15 patients (33.33%). The median time to initial response was 28 days (range, 14-70 days). Furthermore, seven relapsed patients received decitabine retreatment and all showed platelet response, including one complete response and six partial responses. Sustained response rates at 6, 12 and 18 months were 44.44% (20/45), 31.11% (14/45) and 20.0% (9/45), respectively. For responders, immune thrombocytopenia-related symptoms, fatigue, psychological health, fear, and overall quality of life were significantly improved. Adverse events were observed in 13 (28.89%) patients. No serious adverse events were recorded. In conclusion, low dose decitabine is potentially effective and safe in the management of adults with refractory immune thrombocytopenia. This trial is registered with clinicaltrials.gov identifier: NCT01568333.
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Decitabina/uso terapéutico , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Adulto , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Terapia Combinada , Decitabina/administración & dosificación , Decitabina/efectos adversos , Esquema de Medicación , Resistencia a Medicamentos , Sustitución de Medicamentos , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Hemorragia/etiología , Hemorragia/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Recuento de Plaquetas , Estudios Prospectivos , Púrpura Trombocitopénica Idiopática/complicaciones , Púrpura Trombocitopénica Idiopática/cirugía , Calidad de Vida , Recurrencia , EsplenectomíaRESUMEN
Graphene oxide (GO) is an ideal membrane material for water treatment due to its outstanding physicochemical properties and unique lamellar structure. However, the separation performance and practical application of GO membranes are mainly affected by the interlayer spacing and stability in aqueous solutions. Here, we report a novel and facile approach to fabricating GO membranes with adjustable interlayer spacing and high stability in aqueous solutions through cross-linking with polyaluminum chloride (PACl). With this approach, the lamellar spacing can be adjusted by changing the OH/Al ratios (B values) of the PACl, and the GO nanosheets can be tightly bonded by the strong electrostatic effect that PACl provides between them. The average interlayer spacing of the GO layer could be varied approximately in the range of 0.80-1.09 nm. The PACl-GO membranes demonstrated excellent stability in water and inorganic/organic solutions when the concentration of PACl was 0.1, 1, and 10 mM, remaining unchanged for at least 2 weeks. Moreover, the PACl-GO membranes featured exceptional sieving capabilities for model and natural organic substrates, while it was also observed that increasing the interlayer spacing of the PACl-GO membranes increased both the membrane flux and the separation performance of organic matter.
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Grafito , Purificación del Agua , Hidróxido de Aluminio , ÓxidosRESUMEN
OBJECTIVE: To investigate the mRNA expression of galectin-3 and its clinical significance in acute myeloid leukemia (AML) patients carrying AML1/ETOfusion gene. METHODS: RQ-PCR method was used to detect the expression of galectin-3 mRNA in bone marrow mononuclear cells of 53 AML patients with AML1/ETO+, ELISA was used to detect the expression of galectin-3 protein in peripheral blood, and the correlations of galectin-3 expression with clinical and laboratory features and outcomes were analyzed. RESULTS: The mRNA and protein levels of galectin-3 were significantly higher in newly diagnosed AML1/ETO+ AML patients compared with the control ( P<0.001). Galectin-3 mRNA and protein expressions were positively correlated (r=0.732, P<0.001). Galectin-3 protein was significantly decreased during the period of complete remission (CR)( P<0.001). The mRNA expression of galectin-3 was negatively correlated with the count of white blood cells ( P=0.014), and positively correlated with CD34 expression and additional cytogenetic aberrations (ACA) ( P=0.001, P=0.026). There was no significant difference in CR, partial remission (PR), induction death (early mortality) between galectin-3 high-expression group and low-expression group ( P>0.05), but there was significant difference in recurrence rate between the two groups ( P=0.029). The median overall survival (OS) rate and disease-free survival (DFS) rate were shortened in the high-expression group ( P=0.007, P=0.015) and the cumulative incidence of relapse was increased ( P=0.045), but there was no significant difference in the cumulative incidence of CM(155mm]mortality ( P>0.05). Cox regression analysis suggested galectin-3 mRNA level an independent indicator of OS and DFS in AML1/ETO+ AML patients. CONCLUSION: Bone marrow galectin-3 mRNA level may be an important reference index for evaluating the prognosis and guiding the treatment of AML1/ETO+ AML patients.
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Leucemia Mieloide Aguda , Subunidad alfa 2 del Factor de Unión al Sitio Principal , Galectina 3 , Humanos , Proteínas de Fusión Oncogénica , Proteína 1 Compañera de Translocación de RUNX1RESUMEN
Increased galectin-3 expression has been currently showed to be associated with poor prognosis in some hematological malignancies, such as acute myeloid leukemia, diffuse large B cell lymphoma. However, little is known about the clinical significance of galectin-3 in patients with acute promyelocytic leukemia (APL). We investigated the concentration of serum galectin-3 and characterized the relationship between galectin-3 and outcome in patients with APL. Higher galectin-3 levels were detected in patients with APL compared with the healthy controls (p < 0.001). Higher galectin-3 levels were closely associated with older ages (p < 0.001), the medical history of psoriasis (p = 0.036), coagulopathy (p = 0.042), and CD34 expression (p = 0.004). Compared with patients with lower galectin-3 levels, those with higher galectin-3 levels had significant shorter overall survival (p = 0.028) and relapse-free survival (p = 0.001). Multivariate analysis showed that serum galectin-3 was an independent unfavorable factor for relapse-free survival in patients with APL treated with all-trans retinoic acid and arsenic trioxide-based frontline therapy. Clinical impact of galectin-3 should be further investigated in patients with APL.
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Galectina 3/sangre , Leucemia Promielocítica Aguda/sangre , Leucemia Promielocítica Aguda/genética , Proteínas de Fusión Oncogénica/genética , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trióxido de Arsénico , Arsenicales/administración & dosificación , Biomarcadores de Tumor , Estudios de Casos y Controles , Cromosomas Humanos Par 15 , Cromosomas Humanos Par 17 , Femenino , Humanos , Inmunofenotipificación , Leucemia Promielocítica Aguda/diagnóstico , Leucemia Promielocítica Aguda/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Óxidos/administración & dosificación , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia , Translocación Genética , Resultado del Tratamiento , Tretinoina/administración & dosificación , Adulto JovenRESUMEN
MicroRNAs (miRNAs) are small, noncoding ribonucleic acids that regulate gene expression by targeting mRNAs for translational repression and degradation. Accumulating experimental evidence supports a causal role of miRNAs in hematology tumorigenesis. However, the specific functions of miRNAs in the pathogenesis of multiple myeloma (MM) remain to be established. In this study, we demonstrated that miR-186 is commonly downregulated in MM cell lines and patient MM cells. Ectopic expression of miR-186 significantly inhibited cell growth, both in vitro and in vivo, and induced cell cycle G0/G1 arrest. Furthermore, miR-186 induced downregulation of Jagged1 protein expression by directly targeting its 3'-untranslated region (3'-UTR). Conversely, overexpression of Jagged1 rescued cells from miR-186-induced growth inhibition. Our collective results clearly indicate that miR-186 functions as a tumor suppressor in MM, supporting its potential as a therapeutic target for the disease.