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1.
Sci Total Environ ; 920: 171063, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38373452

RESUMO

The primary challenge in mercury (Hg) adsorbents for large-scale practical applications is to achieve the balance between performance and economy. This work attempts to address this issue by synthesizing an exfoliated thiocellulose (CU-SH) with high thiol density and hierarchical porosity using in-situ ligands grafting combined with chemical stripping. The prepared CU-SH shows remarkable physical stability and chemical resistance, and the micron sized fiber is conducive to separation from water. Hg(II) adsorption tests in water demonstrate that CU-SH has broad working pH range (1-12), fast kinetics (0.64 g/(mg‧min)), high adsorption capacity (652.9 mg/g), outstanding selectivity (Kd = 6.2 × 106 mg/L), and excellent reusability (R > 95 % after 20 cycles). Importantly, CU-SH exhibits good resistance to various coexisting ions and organic matter, and can efficiently remove Hg(II) from different real water. CU-SH can be made into a Point of Use (POU) device for continuous and efficient removal of Hg(II) from drinking water. 0.1 g CU-SH filled device can purify 3.2 L of Hg(II) (0.5 ppm) contaminated tap water before the breakthrough point of 2 ppb. Moreover, CU-SH also reveals good adsorption affinity for Hg-dissolved organic matter complexes (Hg(II)-DOM) in water, chloro(phenyl)mercury (PMC) in organic media and Hg0 vapor in air, suggesting the great practical potential of CU-SH.

2.
Anal Methods ; 14(45): 4713-4720, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36342011

RESUMO

Carcinoembryonic antigen (CEA) is regarded as a promising broad spectrum tumor biomarker for clinical diagnosis, progression, and prognosis. Surface plasmon resonance imaging (SPRi) was considered as one of the powerful tools for immunoassay with advantages of label-free, real-time detection with high-throughput. Herein, wavy gold-silver alloy nanoplates functionalized with anti-CEA antibodies providing high protein loading capacity and high mass are used as signal enhancers for CEA detection through SPRi sandwich assay. The present method exhibits a dynamic range for CEA determination from 0.1 to 312.5 ng mL-1 and a detection limit of 0.55 ng mL-1, well below normal physiological levels. This biosensing approach demonstrates the advantages of wavy gold-silver alloy nanoplates compared to conventional gold nanoparticles as a signal amplifier to enhance the SPRi signal, which is expected to become a new prospect for detection of cancer markers in biomedical research and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro , Ressonância de Plasmônio de Superfície/métodos , Antígeno Carcinoembrionário , Prata , Ligas de Ouro , Técnicas Biossensoriais/métodos
3.
Water Res ; 222: 118839, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35870396

RESUMO

Manganese (Mn)-containing composite metal adsorbents are very effective at removing arsenite (As(III)) from contaminated water, however, the low removal speed and oxidation efficiency have limited their further application. In this study, a nonhomogeneous catalytic oxidation-adsorption system was constructed by coupling iron-manganese composite oxide (FeMnOx) with sulfite (S(IV)) to enhance the recovery of oxidative capacity and accelerate the removal of As(III). Experimental results showed that the FeMnOx/S(IV) system decreased the As(III) concentration from 1079 to <10 µg/L within 10 min and almost completely oxidized As(III) to As(V). In contrast, FeMnOx alone removed only 82.4% of As(III) within 30 min, and 60.0% of the adsorbed As(III) was not oxidized. Meanwhile, the adsorption capacity of FeMnOx/S(IV) system for As(III) was considerably higher than that of the only-FeMnOx system (76.5 > 46.3 mg/g). The efficient and fast As(III) removal was attributed to the SO5•- radical generated by S(IV) acting as the driving force for the redox cycle between As(III) and Mn(II/III/IV). Several environmental factors (e.g., solution pH and inorganic anions) and the reusability and practicality of FeMnOx were systematically investigated, and the results further confirmed the superiority of the FeMnOx/S(IV) system in As(III) removal. In particular, the proposed FeMnOx nanocellulose aerogel effectively purified arsenic-contaminated groundwater using a fixed-bed column. Thus, FeMnOx-S(IV) coupling is very promising for the purification of arsenic-contaminated water bodies.


Assuntos
Arsênio , Poluentes Químicos da Água , Purificação da Água , Adsorção , Arsênio/análise , Ferro , Manganês , Oxirredução , Óxidos , Sulfitos , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos
4.
J Hazard Mater ; 422: 126908, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34418837

RESUMO

Here, we prepared a novel nanostructured Fe-Cu-Mn composite oxide (FCMOx) adsorbent using an ultrasonic coprecipitation method. The maximum adsorption capacity of As(III) and As(V) reached 158.5 and 115.2 mg/g under neutral conditions, respectively. The effects of several environmental factors (coexisting ions, solution pH, etc.) on the removal of inorganic arsenic using FCMOx were studied through batch experiments. The results showed that except for PO43- and high initial pH, it was not significantly affected by ionic strength and other existing anions, implying a higher selectivity and adaptability. Combined with EPR, FTIR, and XPS analysis, we concluded that the Cu component and the reactive oxygen species (ROS) it generates played a decisive role in maintaining the stability of the redox cycle between Mn(IV)/Mn(III)/Mn(II) and enhancing the oxidation efficiency of As(III). Meanwhile, the adsorption mechanism of As(V) was mainly through the replacement of the FCMOx surface -OH to form stable inner-sphere arsenic complexes, while the removal mechanism of As(III) may involve the process of synergistic oxidation and chemisorption coupling. Additionally, the effective removal of As from the simulated As-contaminated water and its satisfactory reuse performance make FCMOx adsorbents favorable candidates for the removal of As-contaminated water in the future.

5.
Carbohydr Polym ; 180: 104-111, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29103485

RESUMO

A major challenge in bone tissue engineering is the development of biomimetic scaffolds which should simultaneously meet mechanical strength and pore structure requirements. Herein, we combined technologies of high concentration solvent casting, particulate leaching, and room temperature compression molding to prepare a novel poly(lactic acid)/ethyl cellulose/hydroxyapatite (PLA/EC/HA) scaffold. The functional, structural and mechanical properties of the obtained porous scaffolds were characterized. The results indicated that the PLA/EC/HA scaffolds at the 20wt% HA loading level showed optimal mechanical properties and desired porous structure. Its porosity, contact angle, compressive yield strength and weight loss after 56days were 84.28±7.04%, 45.13±2.40°, 1.57±0.09MPa and 4.77±0.32%, respectively, which could satisfy the physiological demands to guide bone regeneration. Thus, the developed scaffolds have potential to be used as a bone substitute material for bone tissue engineering application.


Assuntos
Substitutos Ósseos/síntese química , Celulose/análogos & derivados , Hidroxiapatitas/química , Poliésteres/química , Tecidos Suporte/química , Substitutos Ósseos/química , Interações Hidrofóbicas e Hidrofílicas , Porosidade
6.
Bioresour Technol ; 245(Pt A): 649-655, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28917099

RESUMO

Developing versatile materials for effective water purification is significant for environment and water source protection. Herein, a versatile bio-based material (CH-PAA-T) was reported by simple thermal cross-linking chitosan and polyacrylic acid which exhibits excellent performances for removing insoluble oil, soluble toxic dyes and heavy metal ions from water, simultaneously. The adsorption capacities are 990.1mgg-1 for methylene blue (MB) and 135.9mgg-1 for Cu2+, which are higher than most of present advanced absorbents. The adsorption towards organic dyes possesses high selectivity which makes CH-PAA-T be able to efficiently separate dye mixtures. The stable superoleophobicity under water endows CH-PAA-T good performance to separate toluene-in-water emulsion stabilized by Tween 80. Moreover, CH-PAA-T can be recycled for 10 times with negligible reduction of efficiency. Such versatile bio-based material is a potential candidate for water purification.


Assuntos
Corantes , Poluentes Químicos da Água , Purificação da Água , Adsorção , Íons , Metais Pesados , Água
7.
Carbohydr Polym ; 175: 636-644, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917912

RESUMO

A plant-based non-formaldehyde flame retardant containing high phosphorus ammonium phytate (APA) was synthesized for cotton fabric. The char length of treated cotton sample decreased to 31mm from the original 300mm. The LOI value of finished cotton fabric was as high as 43.2%, and after 30 laundering cycles, it still remained 30.5%, suggesting that APA could be used as an effective semi-durable flame retardant. The TG analysis in air demonstrated that the thermal oxidation stability of treated fabric was significantly improved. Cone calorimetry results showed that the peak heat release rate and total heat release of treated sample reduced obviously comparing with that of control sample. The SEM morphologies suggested that the APA molecule penetrated into the inner space of cotton fibers. FTIR spectra implied the APA molecule grafted onto cotton fibers. Then, the effective flame retardant APA has significant potential in practical application.

8.
ACS Appl Mater Interfaces ; 8(43): 29400-29407, 2016 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-27731623

RESUMO

The development of high-efficiency catalysts for hydrogen evolution via water splitting has been an effective strategy to solve the energy environmental problems and energy crisis. The abundant-reserving transition metals and their phosphides are becoming attractive Pt alternatives for hydrogen evolution reaction (HER). Herein, a crystalline/amorphous Co/CoP film was facilely prepared on nickel foam (NF) by a one-step electrodeposition technique at room temperature, named Co/CoP-NF. The as-prepared Co/CoP-NF electrocatalyst exhibits excellent electrocatalytic activity for HER, on par with Pt/C, showing a low overpotential of 35 mV at a current density of 10 mA·cm-2 and small Tafel slope of 71 mV·dec-1 in 1.0 M NaOH solution. More importantly, the Co/CoP-NF catalyst presents good long-term durability at an overpotential of 60 mV. Moreover, the influence of the electrodeposition parameters on the catalytic performance of the catalyst was discussed. This study offers an effective strategy to develop a non-noble-metal HER catalyst for industrial production of hydrogen.

9.
Korean J Parasitol ; 52(5): 521-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25352701

RESUMO

Human infections with Lophomonas blattarum are rare. However, the majority of the infections occurred in China, 94.4% (136 cases) of all cases in the world. This infection is difficult to differentiate from other pulmonary infections with similar symptoms. Here we reported a case of L. blattarum infection confirmed by bronchoalveolar lavage fluid smear on the microscopic observations. The patient was a 21-year-old female college student. The previous case which occurred in Chongqing was 20 years ago. We briefly reviewed on this infection reported in the world during the recent 20 years. The epidemiological characteristics, possible diagnostic basis, and treatment of this disease is discussed in order to provide a better understanding of recognition, diagnosis, and treatment of L. blattarum infection.


Assuntos
Pneumopatias Parasitárias/parasitologia , Parabasalídeos/isolamento & purificação , Infecções por Protozoários/parasitologia , Feminino , Humanos , Pneumopatias Parasitárias/diagnóstico , Adulto Jovem
10.
PLoS One ; 9(2): e88330, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24505476

RESUMO

Multi-drug resistant tuberculosis (MDR-TB) represents a threat to health and development in countries with high TB burden. China's MDR-TB prevalence rate of 6.8% is the highest in the world. Interventions to remove barriers against effective TB control, and prevention of MDR-TB are urgently needed in the country. This paper reports a cross-sectional questionnaire survey of 513 pulmonary TB (PTB) patients, and qualitative interviews of 10 healthcare workers (HCWs), and 15 PTB patients. The objective was to assess barriers against effective control of PTB and prevention of MDR-TB by elucidating the perspectives of patients and healthcare providers. Results showed that more than half of the patients experienced patient delay of over 12.5 days. A similar proportion also experienced detection delay of over 30 days, and delay in initiating treatment of over 31 days. Consulting a non-TB health facility ≥3 times before seeking care at TB dispensary was a risk factor for both detection delay [AOR (95% CI): 1.89(1.07, 3.34) and delay in initiating treatment[AOR (95% CI): 1.88 (1.06, 3.36). Results revealed poor implementation of Directly Observed Therapy (DOT), whereby treatment of 34.3% patients was never monitored by HCWs. Only 31.8% patients had ever accessed TB health education before their TB diagnosis. Qualitative data consistently disclosed long patient delay, and indicated that patient's poor TB knowledge and socioeconomic barriers were primary reasons for patient delay. Seeking care and being treated at a non-TB hospital was an important reason for detection delay. Patient's long work hours and low income increased risk for treatment non-adherence. Evidence-based measures to improve TB health seeking behavior, reduce patient and detection delays, improve the quality of DOT, address financial and system barriers, and increase access to TB health promotion are urgently needed to address the burgeoning prevalence of MDR-TB in China.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , China/epidemiologia , Efeitos Psicossociais da Doença , Estudos Transversais , Terapia Diretamente Observada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Fatores Socioeconômicos , Inquéritos e Questionários , Tuberculose Resistente a Múltiplos Medicamentos/economia , Tuberculose Resistente a Múltiplos Medicamentos/terapia , Tuberculose Pulmonar/economia , Tuberculose Pulmonar/terapia , Adulto Jovem
11.
BMJ Open ; 3(9): e003454, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-24056486

RESUMO

OBJECTIVES: Tuberculosis (TB) control in schools is a concern in low-income and middle-income countries with high TB burdens. TB knowledge is recognised as important for TB control in China, which has one of the highest TB prevalence in the world. Accordingly, National TB Control Guideline in China emphasised TB-health education in schools as one of the core strategies for improving TB knowledge among the population. It was important to assess the level of TB knowledge in schools following 5-year implementation of the guideline, to determine whether the information was reaching the targets. DESIGN: A cross-sectional study. METHODS AND STUDY SETTING: This survey assessed TB knowledge and access to TB-health information by questionnaire survey with 1486 undergraduates from two medical universities in Southwest China. RESULTS: Overall, the students had inadequate TB knowledge. Only 24.1%, 27.2% and 34.1% of the students had knowledge of TB symptoms of cough/blood-tinged sputum, their local TB dispensaries and free TB treatment policy, respectively. Very few (14.5%) had heard about the Directly Observed Therapy Short Course (DOTS), and only about half (54%) had ever accessed TB-health education information. Exposure to health education messages was significantly associated with increased knowledge of the five core TB knowledge as follows: classic TB symptoms of cough/blood-tinged sputum (OR (95% CI) 0.5(0.4 to 0.7)), TB modes of transmission (OR (95% CI) 0.4(0.3 to 0.5)), curability of TB (OR (95% CI) 0.6(0.5 to 0.7)), location and services provided by TB local dispensaries (OR (95% CI) 0.6(0.5 to 0.8)) and the national free TB treatment policy (OR (95% CI) 0.7(0.5 to 0.8)). CONCLUSIONS: The findings pose the question of whether it is time for a rethink of the current national and global approach to TB-health education/promotion which favours promotion of awareness on World TB Days rather than regular community sensitisation efforts.

12.
BMC Med ; 11: 156, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23819847

RESUMO

BACKGROUND: Delay in seeking care is a major impediment to effective management of tuberculosis (TB) in China. To elucidate factors that underpin patient and diagnostic delays in TB management, we conducted a systematic review and meta-analysis of factors that are associated with delays in TB care-seeking and diagnosis in the country. METHODS: This review was prepared following standard procedures of the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and checklist. Relevant studies published up to November 2012 were identified from three major international and Chinese literature databases: Medline/PubMed, EMBASE and CNKI (China National Knowledge Infrastructure). RESULTS: We included 29 studies involving 38,947 patients from 17 provinces in China. Qualitative analysis showed that key individual level determinants of delays included socio-demographic and economic factors, mostly poverty, rural residence, lack of health insurance, lower educational attainment, stigma and poor knowledge of TB. Health facility determinants included limited availability of resources to perform prompt diagnosis, lack of qualified health workers and geographical barriers.Quantitative meta-analysis indicated that living in rural areas was a risk factor for patient delays (pooled odds ratio (OR) (95% confidence interval (CI)): 1.79 (1.62, 1.98)) and diagnostic delays (pooled OR (95% CI): 1.40 (1.23, 1.59)). Female patients had higher risk of patient delay (pooled OR (95% CI): 1.94 (1.13, 3.33)). Low educational attainment (primary school and below) was also a risk factor for patient delay (pooled OR (95% CI): 2.14 (1.03, 4.47)). The practice of seeking care first from Traditional Chinese Medicine (TMC) providers was also identified as a risk factor for diagnostic delay (pooled OR (95% CI): 5.75 (3.03, 10.94)). CONCLUSION: Patient and diagnostic delays in TB care are mediated by individual and health facility factors. Population-based interventions that seek to reduce TB stigma and raise awareness about the benefits of early diagnosis and prompt treatment are needed. Policies that remove patients' financial barriers in access to TB care, and integration of the informal care sector into TB control in urban and rural settings are central factors in TB control.


Assuntos
Povo Asiático/etnologia , Diagnóstico Tardio , Estilo de Vida/etnologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/etnologia , Diagnóstico Tardio/prevenção & controle , Diagnóstico Precoce , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Humanos , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Fatores de Risco , Fatores de Tempo , Tuberculose Pulmonar/terapia
13.
BMC Health Serv Res ; 9: 181, 2009 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-19814832

RESUMO

BACKGROUND: Community health services in China have developed over the last few decades. In order to use limited health resources more effectively, we conducted a community health needs assessment. This aimed to provide an understanding of the community's health problems and the range of potential factors affecting risk behaviours for the priority health problems. METHODS: We used the precede-proceed model for the needs assessment. Triangulation of data, methods and researchers were employed in data collection. RESULTS: Main findings include: cardiovascular diseases (CVDs) were identified as the priority health problems in the study communities; risk factors associated with CVDs included smoking, physical inactivity and unhealthy eating behaviours, particularly amongst male residents with low education level; factors negatively affecting behaviours were classified into predisposing factors (limited knowledge, beliefs and lack of perceived needs), enabling factors (limited access to health promotion activities, unawareness of health promotion, lack of work-site and school health promotion, absence of health promotion related policy) and reinforcing factors (culture). Policies and organization were not perfect; there were limited staff skilled in providing health promotion in the community. CONCLUSION: CVDs were identified by the communities as priority health problems. Future health programs should focus on smoking, physical inactivity and unhealthy eating behaviours. Behaviour change strategies should take predisposing factors, enabling factors and reinforcing factors into consideration. Policies, organization and human resource need strengthening.


Assuntos
Serviços de Saúde Comunitária , Participação da Comunidade , Prioridades em Saúde , Determinação de Necessidades de Cuidados de Saúde , Avaliação de Processos em Cuidados de Saúde/métodos , Adulto , China , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Assunção de Riscos , Inquéritos e Questionários
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