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1.
Artigo em Inglês | MEDLINE | ID: mdl-38969612

RESUMO

With advancements in extracorporeal life support (ECLS) technologies, venoarterial extracorporeal membrane oxygenation (VA-ECMO) has emerged as a crucial cardiopulmonary support mechanism. This review explores the significance of VA-ECMO system configuration, cannulation strategies, and timing of initiation. Through an analysis of medication management strategies, complication management, and comprehensive preweaning assessments, it aims to establish a multidimensional evaluation framework to assist clinicians in making informed decisions regarding weaning from VA-ECMO, thereby ensuring the safe and effective transition of patients.

2.
Dalton Trans ; 52(31): 10835-10843, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37485915

RESUMO

A low operating temperature and short response/recovery time are essential factors for sensors. Hence, it is necessary to create a sensor that can quickly detect target gas at a relatively low temperature. In this work, Co3O4 microtube based sensors were fabricated by a bio-template method using absorbent cotton. Co3O4 microtube sensors prepared in different concentrations of a salt solution displayed different sensitivities to triethylamine (TEA). The Co3O4-0.10 microtube sensor exhibited excellent sensitivity to TEA at 160 °C. The response of the Co3O4-0.10 sensor to 100 ppm TEA gas was 31.27 and the detection limit of TEA was 50 ppb. Meanwhile, the Co3O4-0.10 sensor also showed a short response/recovery time, such as 95 s/38 s to 100 ppm TEA, high selectivity, a good linear relationship (R2 = 0.994 for 1-100 ppm TEA and R2 = 0.991 for 50-1000 ppb TEA gas), fine repeatability and long-term stability, and strong humidity resistance. Thus, Co3O4 microtube based sensors prepared using a bio-template method have potential application prospects for the detection of TEA gas.

3.
Water Sci Technol ; 87(8): 1879-1892, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37119161

RESUMO

Soluble iron and sulfate in acid mine drainage (AMD) can be greatly removed through the formation of minerals facilitated by seed crystals. However, the difference in the effects of jarosite and schwertmannite as endogenous seed crystals to induce AMD mineralization remains unclear. This paper intends to study the effect of Fe2+ oxidation and Fe3+ mineralization in the biosynthesis of minerals using different addition amounts and methods of jarosite or schwertmannite. The results showed that the addition amount and method of different seed crystals had no effect on the Fe2+ bio-oxidation but would change the Fe3+ mineralization efficiency. With the same amount of seed crystals added, jarosite exhibited a higher capacity to promote Fe3+ mineralization than schwertmannite. Adding seed crystals before the initiation of Fe2+ oxidation (0 h) could significantly promote Fe3+ mineralization efficiency. With the increase of seed crystals, jarosite could not only shorten the time required for mineral synthesis but also improve the final mineral yield, whereas schwertmannite could only shorten the time required for mineral synthesis. When Fe2+ was completely oxidized to Fe3+ (48 h), the supplementary of jarosite could still effectively improve Fe3+ mineralization efficiency, but the addition of schwertmannite no longer affected the final mineralization degree.


Assuntos
Acidithiobacillus , Compostos de Ferro , Ferro , Biomineralização , Compostos de Ferro/química , Compostos Férricos/química , Minerais , Oxirredução
4.
Water Res ; 221: 118748, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35728497

RESUMO

Acid mine drainage (AMD) contains abundant iron, sulfates, and various metal ions, and it causes environmental pollution. The traditional AMD lime neutralization forms a layer of iron hydroxide and gypsum on the surface of the lime particles, preventing continuous reaction and leading to excessive lime addition and neutralized sludge production. In this study, an approach for treating AMD using a cyclic process of biooxidation and electroreduction before lime neutralization was proposed, in which the Fe2+ in AMD was oxidized to Fe3+ and induced to form schwertmannite through Acidithiobacillus ferrooxidans. The remaining Fe3+ was reduced to Fe2+ using an electric field. After three biooxidation and two electroreduction cycles, 98.2% of Fe and 62.4% of SO42- in AMD precipitated as schwertmannite (Fe8O8(OH)5.16(SO4)1.37). The yield of schwertmannite reached 33.98 g/LAMD, with a high specific surface area of 112.59 m2/g. The lime dosage and sludge yield of the treated AMD in the subsequent neutralization stage (pH = 7.00) decreased by 85.0% and 74.5%, respectively, than those of raw AMD. The pilot test results showed that the integrated treatment of biooxidation-electroreduction cyclic mineralization and lime neutralization has practical applications.


Assuntos
Esgotos , Poluentes Químicos da Água , Ácidos , Compostos de Cálcio , Concentração de Íons de Hidrogênio , Ferro , Compostos de Ferro , Óxidos , Poluentes Químicos da Água/análise
5.
J Int Med Res ; 49(1): 300060520984656, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33472471

RESUMO

Aortopulmonary window is a rare congenital heart disease that can increase pulmonary vascular resistance, exacerbate left-to-right shunt and lead to heart failure and respiratory tract infections. Most patients die during childhood. We report a 53-year-old male patient with a large aortopulmonary window combined with anomalous origin of the right pulmonary artery from the aorta, with Eisenmenger syndrome and without surgery.


Assuntos
Defeito do Septo Aortopulmonar , Complexo de Eisenmenger , Adulto , Aorta/diagnóstico por imagem , Aorta/cirurgia , Defeito do Septo Aortopulmonar/diagnóstico por imagem , Defeito do Septo Aortopulmonar/cirurgia , Complexo de Eisenmenger/complicações , Complexo de Eisenmenger/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/cirurgia , Resistência Vascular
6.
Environ Technol ; 42(15): 2325-2334, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31797752

RESUMO

The oxidation of Fe2+ by Acidithiobacillus ferrooxidans (A. ferrooxidans) in acid mine drainage (AMD) is often accompanied by formation of iron hydroxysulfate minerals, such as schwertmannite and jarosite. This study reported that 80 mmol L-1 of Fe2+ could be completely oxidized by A. ferrooxidans LX5 within 48 h, but only 27.7% of the resultant Fe3+ precipitated to form schwertmannite. However, the conversion efficiency to jarosite was much higher (54.5%). The formation of jarosite lasted 120 h, while only 24 h when conversed to schwertmannite. By constructing a cyclic process of 'Cu-reducing coupled with bio-oxidization', the total Fe in AMD could be fully converted into mineral precipitates. The resultant mineral specie could be regulated simply by control the K+ concentration. Thermodynamically, Fe3+ cannot hydrolyze spontaneously to form schwertmannite due to the positive Gibbs free energy (ΔrGm∘ = 6.63 kJ mol-1) of the reaction. However, if Fe2+ were biologically oxidized by A. ferrooxidans, the resultant Fe3+ could spontaneously form schwertmannite because the aforementioned coupling reaction has a negative Gibbs free energy (ΔrGm∘ = -34.12 kJ mol-1). Even though Fe3+ itself could hydrolyze to form jarosite spontaneously with ΔrGm∘ = -22.20 kJ mol-1, the coupling reaction of Fe2+ bio-oxidation followed by Fe3+ hydrolysis in the presence of K+ could easily promote the formation of jarosite, which exhibited a great negative Gibbs energy (ΔrGm∘ = -67.45 kJ mol-1).


Assuntos
Acidithiobacillus , Ferro , Compostos Férricos , Hidrólise , Minerais , Oxirredução
7.
Anal Chim Acta ; 1120: 59-66, 2020 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-32475392

RESUMO

Plants have excellent abilities to regenerate from detached tissues, in which various phytohormones play critical roles. It has been reported that jasmonate and auxin appeared sequentially during direct de novo root regeneration (DNRR) after leave detachment. However, the role of salicylic acid (SA) is still unknown in this procedure although it is another important plant hormone. We have demonstrated the potential of electrochemical sensors for real time screening of SA but the stability still needed to be improved. Herein a digital plotter was used to modify the carbon tape modified electrodes with pencil traces in order to improve the reproducibility. The modified electrodes in paper-based analytical devices were applied to monitor SA during direct DNRR. The drawing routines and the distances between two close traces were optimized. Our results showed that the carbon tape modified electrodes achieved more reproducible responses of SA. Combined with in vivo sampling, the results using our approach demonstrated that amounts of SA in the wild Arabidopsis thaliana leaves during direct DNRR reached highest at around 72 h after detachment and then decreased, implying that the wave of SA contents might follow that of auxin during direct DNRR. The application of the digital plotter offered a cost-effective and more reproducible method for preparation of disposable working electrodes, which might be extended for other biochemical assays.


Assuntos
Arabidopsis/química , Folhas de Planta/química , Ácido Salicílico/metabolismo , Arabidopsis/metabolismo , Carbono/química , Eletrodos , Folhas de Planta/metabolismo , Ácido Salicílico/análise , Fatores de Tempo
8.
Int J Biol Sci ; 15(10): 2128-2138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592122

RESUMO

With the increasing incidence of thoracic tumors, radiation therapy (RT) has become an important component of comprehensive treatment. RT improves survival in many cancers, but it involves some inevitable complications. Radiation-induced heart disease (RIHD) is one of the most serious complications. RIHD comprises a spectrum of heart disease including cardiomyopathy, pericarditis, coronary artery disease, valvular heart disease and conduction system abnormalities. There are numerous clinical manifestations of RIHD, such as chest pain, palpitation, and dyspnea, even without obvious symptoms. Based on previous studies, the pathogenesis of RIHD is related to the production and effects of various cytokines caused by endothelial injury, inflammatory response, and oxidative stress (OS). Therefore, it is of great importance for clinicians to identify the mechanism and propose interventions for the prevention of RIHD.


Assuntos
Cardiopatias/etiologia , Cardiopatias/prevenção & controle , Lesões por Radiação , Animais , Cardiopatias/classificação , Humanos , Estresse Oxidativo/efeitos da radiação
9.
Biomed Pharmacother ; 118: 109217, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31302424

RESUMO

Radiotherapy (RT) is currently one of the leading treatment for various cancers and it may cause injury to healthy tissue, with both short-term and long-term side effects. Inflammatory responses play an important role in the adverse reactions of early and late ionizing radiation. Nucleotide-binding domain and leucine-rich-repeat-containing family pyrin 3 (NLRP3) inflammasome as a multi-protein complex that activates caspase-1 can give rise to the proinflammatory cytokines such as interleukin-18 (IL-18) and interleukin-1 beta (IL-1ß) maturation. Recent experiments and studies have shown that up-regulation of NLRP3 inflammasome have a big impact on radiation damage, which include radiation-induced oral mucositis, radiation-induced skin reactions, radiation-induced lung damage, radiation-induced intestinal injury and radiation-induced changes in other systems. In this paper, we will review the role of NLRP3 inflammasome in radiation damage, to explore possible therapeutic strategies for radiation damage.


Assuntos
Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Lesões por Radiação/metabolismo , Lesões por Radiação/patologia , Animais , Humanos , Especificidade de Órgãos , Transdução de Sinais
10.
Waste Manag ; 87: 13-20, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31109512

RESUMO

Titanium white waste acid (TWWA) is strongly acidic, and has high metatitanic acid (TiO(OH)2) and n-hexane (C6H14) content. In this study, the effects of polyvinyl alcohol (PVA) on the modification of TWWA deacidification were evaluated via pilot testing. The results showed that the PVA solution can significantly improve the deacidification performance of TWWA. The TWWA specific resistance to filtration (SRF) decreased from the initial 2.42 × 1013 m/kg to 1.80 × 1012 m/kg when 2% PVA solution was added at 25% (v/v). Furthermore, the amount of filter press-processed TWWA increased by 3.56 m3 relative to the control, and the moisture content of titanium white slag was only 42.02% after deacidification. In addition, distillation and phase separation was demonstrated to efficiently separate C6H14 and hydrochloric acid (HCl) from the mixed filtrate. Moreover, titanium white slag was converted into rutile after 60 min when the calcination temperature was 900 °C, with the titanium dioxide (TiO2) purity of rutile reaching 91.83%. Accordingly, the TWWA recycling process proceeded as follows: PVA modification, solid-liquid separation, filtrate distillation and phase separation, and titanium white slag calcination. Our findings demonstrate that this process has unique practical application value.


Assuntos
Álcool de Polivinil , Titânio , Ácidos , Destilação , Filtração
11.
Materials (Basel) ; 11(9)2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30223571

RESUMO

Schwertmannite is an environmental mineral material that can promote the natural passivation of heavy metal elements, thereby reducing environmental pollution from toxic elements. However, the fundamental reason for the difference between the chemically (H2O2-FeSO4) and biologically (Acidithiobacillus ferrooxidans-FeSO4) synthesized schwertmannite is still unclear. In this study, X-ray diffraction, scanning electron microscopy, the Brunauer⁻Emmett⁻Teller method, and X-ray fluorescence spectrometry were used to compare the structure, specific surface area, and elemental composition of schwertmannite synthesized by biological and chemical methods. The removal capacity of As(III) by the two kinds of schwertmannite and the effects of extracellular polymeric substances (EPS) on biogenetic schwertmannite were also investigated. At a consistent Fe2+ oxidation efficiency, the chemical method synthesized more schwertmannite than the biological method over a 60-h period. The biosynthesized schwertmannite had a "chestnut shell" shape, with a larger particle size and specific surface than the chemically synthesized schwertmannite, which was relatively smooth. The saturated adsorption capacities of the biologically and chemically synthesized schwertmannite were 117.0 and 87.0 mg·g-1, respectively. After exfoliation of the EPS from A. ferrooxidans, the biosynthesized schwertmannite displayed a "wool ball" shape, with rough particle surfaces, many microporous structures, and a larger specific surface area. The schwertmannite yield also increased by about 45% compared with that before exfoliation, suggesting that the secretion of EPS by A. ferrooxidans can inhibit the formation of schwertmannite.

12.
Water Sci Technol ; 78(10): 2183-2192, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30629546

RESUMO

It is of practical significance to promote the transformation of Fe in acid mine drainage (AMD) into ferric hydroxysulfate minerals with strong ability to remove heavy metals or metalloids. To investigate the types of biogenic ferric hydroxysulfate minerals generated in AMD by Acidithiobacillus ferrooxidans (A. ferrooxidans), different pH and K+ concentrations are tested for the formation of precipitates in media containing 160 mmol/L Fe2+. The Cr(VI) removal efficiencies of ferric hydroxysulfate minerals in AMD with different acidities are also compared. Results indicate that the mineralizing abilities of the initial pH levels (pH 3.0 > pH 2.5 > pH 2.0) and K+ concentrations (53.3 mmol/L > 3.2 mmol/L ≈ 0.8 mmol/L) differ, with cumulative Fe precipitation efficiencies of 58.7%, 58.0%, and 44.2% (K+ = 53.3 mmol/L), and 58.7%, 29.9%, and 29.6% (pH 3.0) after 96 h of A. ferrooxidans incubation, respectively. X-ray diffraction indicates that K-jarosites are formed in the treatments n(Fe)/n(K) = 0.1 and 3 at pH 2.0-3.0, while only schwertmannite is generated in a system of pH 3.0 and n(Fe)/n(K) = 200. X-ray photoelectron spectroscopy reveals that HCrO4 - may be adsorbed as an inner-sphere complex on schwertmannite when the AMD pH is 3.0.


Assuntos
Cromo/química , Minerais/química , Potássio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Cromo/análise , Compostos Férricos , Concentração de Íons de Hidrogênio , Mineração , Poluentes Químicos da Água/análise
13.
RSC Adv ; 8(2): 1039-1046, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35538942

RESUMO

Acid mine drainage (AMD) is typically characterized by low pH, a high concentration of sulfate and dissolved heavy metals. Therefore, it is of practical significance to promote the transformation of soluble Fe and SO4 2- into iron hydroxysulfate minerals by biomineralization of Acidithiobacillus ferrooxidans. This enhances the lime neutralization efficiency of AMD by reducing the production of ferric hydroxide and waste gypsum. In this study, a new microbial enhanced plug-flow ditch reaction system was developed for the pretreatment of AMD on a semi-pilot scale. System stability under different hydraulic retention times (HRTs) was examined and the effects of microbe enhancement-lime neutralization technology and direct lime neutralization technology were compared. The bio-oxidation efficiency of Fe2+ (5 g L-1) reached 100% in some parts of the system when HRT was 3 and 2 days, and the time taken to reach steady state was 6 and 4 days, respectively. When the HRT was 1 day, the reaction system had operated for 4 days before the equilibrium was lost. At the optimum HRT (2 days) and after the system was stable, the average precipitation rate of total Fe was 53.62% and the average removal rate of As(iii) was 17.27%. Following microbial enhanced pretreatment, the amount of lime required and waste residues generated for AMD neutralization decreased by 75.00% and 85.25%, respectively. This result supports the application of microbial enhancement-lime neutralization passive treatment technology for AMD.

14.
Huan Jing Ke Xue ; 35(4): 1407-13, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24946595

RESUMO

It is practically important that high concentrations of organic pollutants in landfill leachate were degraded by a rapid and efficient approach. The influence of operating conditions such as schwertmannite dosage, V(H2O2)/m (schwertmannite) ratio on the degradation efficiency of color, TOC and COD contents of landfill leachate, was investigated by using the schwertmannite/H2O2/UV process. It was demonstrated that the color, TOC and COD removal efficiencies increased significantly with the increase in schwertmannite dosage, and then were approximately stable. However, COD removal efficiency declined because of the presence of the residual H2O2 when V (H2O2)/m (schwertmannite) was greater than 2, and the best removal efficiency of COD was 44.9%. Furthermore, high-intensity ultraviolet was more conducive to eliminate pollutants through photochemical oxidation with schwertmannite/H2O2. The color, TOC and COD removal efficiencies were 90.0%, 78.8% and 52.6% respectively after 2.5 hours of photochemical degradation, with UV-500 W under optimal initial pH = 2.5; meanwhile, this study found that it was beneficial to the photochemical degradation of leachate at room temperature via the schwertmannite/H2O2/UV process, and COD removal efficiency declined gradually when the temperature was higher than 25 degrees C. Controlled trials showed that the schwertmannite/H2O2 method was conducive to the removal of color compared with the traditional homogeneous Fenton reaction.


Assuntos
Peróxido de Hidrogênio/química , Compostos de Ferro/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Cor , Oxirredução , Processos Fotoquímicos , Eliminação de Resíduos , Temperatura
15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 36(5): 315-9, 2002 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-12411191

RESUMO

OBJECTIVE: To understand the prevalence and spatial distribution of vitamin A deficiency (VAD) in China among children at ages under six years. METHODS: About 8,600 children under 6 years of age in 14 cities and 28 counties of 14 provinces were selected with stratified cluster sampling for survey, including interview with questionnaire for their family information and nutritional status. Blood specimens were collected for measuring serum level of VA with fluorescent spectrophotometry in laboratory. RESULTS: Totally, 8,669 children under 6 (2,877 in urban area and 5,792 in rural area) were surveyed in 14 provinces, with 4,629 males and 4,040 females. Eight cases of night blindness and seven cases of xerophthalmia were found among the children at ages of two to five years. Sixty-one mothers of the children in this group were also found suffering from night blindness. All the cases of night blindness and xerophthalmia both in children and mothers were living in rural areas. Based on their serum levels of VA, 11.7% of the all 1 018 children were diagnosed as VAD, with serum VA concentrations below or equal to 0.70 micro mol/L. Prevalence of VAD was 15.0% and 5.8% in rural (23.3% in the poverty-stricken counties) and urban areas, respectively, and 5.8%, 11.5% and 16.8% in the coastal, inland and remote areas, respectively. The average serum level of VA was 1.20 micro mol/L and 0.99 micro mol/L for urban and rural areas, respectively, with a national average of 1.06 micro mol/L. And, babies under six months of age with an average serum levels of VA < or = 0.70 micro mol/L accounted for 33.4%, and those at ages of four to five years with the same level of VA accounted for 8%. There was significant difference in serum levels of VA between ages, but no significant difference between genders. CONCLUSION: VAD did exist in children of China, especially in the remote and poverty-stricken rural areas and VA supplementation is urgently needed for the children in these regions.


Assuntos
Deficiência de Vitamina A/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Suplementos Nutricionais , Feminino , Inquéritos Epidemiológicos , Humanos , Lactente , Masculino , Cegueira Noturna/complicações , Prevalência , Saúde da População Rural/estatística & dados numéricos , Vitamina A/administração & dosagem , Vitamina A/uso terapêutico , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/prevenção & controle , Xeroftalmia/complicações
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