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1.
J Hazard Mater ; 467: 133752, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38350320

RESUMO

A remarkably efficient and affordable Fe/Cu bimetallic catalyst featuring a substantial light energy utilization and compatibility with a sizable substrate was developed for Fenton-like reactions aimed at pollutant control. Specifically, a novel strategy was employed to synthesize high-density metal sites (Fe:Cu ≈ 3:1) robustly embedded on polyethylene/polyethylene terephthalate nonwoven fabric (PE/PET NWF) via radiation-induced graft polymerization (RIGP) and subsequent chemical modification, labeled as Fe/Cu-PPAO. Its high effectiveness was demonstrated by degrading 50 mg/L of tetracycline hydrochloride within 30 min in the presence of H2O2 under simulate sunlight irradiation. It was investigated that amidoxime groups regulated the optical gaps and HOMO-LUMO gaps of metal ions to enable the absorption of a broader spectrum light while the Cu2+ facilitated the transfer of electrons between the bimetal ions to achieve an improved reaction path. Furthermore, X-ray absorption fine structure (XAFS) and density functional theory (DFT) calculations further revealed its special complex state and delicate electronic structure between bimetal ions and amidoxime groups. Our study offers a new strategy to synthesize high-density bimetallic sites catalyst for environmental remediation and pushes forward insight into understanding the catalytic mechanism of bimetallic Fenton-like catalysts.

2.
Gels ; 8(10)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36286185

RESUMO

In recent years, the treatment of textile waste has attracted more and more attention around the world. The reuse of textile waste can contribute to the reduction of carbon emissions and the sustainable development of the economy. Herein, we proposed a facile and cost-effective approach to fabricating aerogel by using textile waste fibers as the matrix and polyvinyl alcohol (PVA) and glutaraldehyde (GA) as crosslinking agents. After being modified with methyltrimethoxysilane (MTMS) via chemical vapor deposition, both the interior and exterior of the textile waste aerogels exhibit a hydrophobic property with a water contact angle of up to 136.9° ± 2.3°. A comprehensive investigation of the structure, thermal properties, mechanical properties and oil absorption capacity of this aerogel shows its potential for building insulation and oil spill cleanup. The textile waste fibers aerogels have low density and high porosity, good thermal stability and outstanding heat insulation properties (Kavg. = 0.049-0.061 W/m·K). With a maximum oil absorption value of 26.9 ± 0.6 g/g and rapid and effective oil/water mixture separation, the aerogel exhibits competitive commercial application value.

3.
J Hazard Mater ; 423(Pt A): 127051, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523502

RESUMO

The aim of this study was to investigate the primary mechanism of magnetite promoting anaerobic degradation of aromatic compounds under the low-concentration sulphate conditions. Under influent conditions of benzoate at 50 mM-chemical oxygen demand (COD) and sulphate at 15 mM, magnetite promoted benzoate degradation (77.1% vs 56.3%), while the effluent sulphate concentration was slightly higher than that without magnetite (1.6 mM vs 0.7 mM), inconsistent with functional gene prediction that both sulphate respiration and sulphur compound respiration were relatively more active in the presence of magnetite. Remarkably, X-ray diffraction showed that, signal related to Fe3O4 faded away and finally was replaced by FeSO4 and FeS, indicating that magnetite participated in benzoate degradation coupled to sulphate reduction via dissimilatory Fe(III) reduction. Further X-ray photoelectron spectroscopy showed that, signal related to S0 was only detected with magnetite, suggesting the possibility of re-oxidation of sulphide to elemental sulphur coupled to Fe(III) reduction. This was further supported by the increase in abundance of Desulfuromonas acetexigens capable of growing on Fe(III). In addition, magnetite specially enriched the chemolithotrophic sulphur-disproportionating microbes, Desulfovibrio aminophilus, which might proceed the disproportionation of elemental sulphur to sulphate and sulphide to achieve a sulphur cycle for benzoate degradation.


Assuntos
Óxido Ferroso-Férrico , Sulfatos , Anaerobiose , Benzoatos , Elétrons , Compostos Férricos , Oxirredução , Enxofre
4.
J Am Chem Soc ; 131(10): 3713-20, 2009 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-19245204

RESUMO

Maximizing the thermoelectric figure-of-merit (ZT) is a challenge owing to the conflicting combination of material properties. We explored simultaneously enhancing the power factor and reducing the thermal conductivity through filling In in Ba-filled skutterudite (Ba(0.3)Co(4)Sb(12)). Two large ZT values of 1.33 and 1.34 have been achieved for Ba(0.15)In(0.16)Co(4)Sb(11.83) and Ba(0.14)In(0.23)Co(4)Sb(11.84) at 850 K, respectively. The excellent thermoelectric transport properties for Ba(r)In(s)Co(4)Sb(12) are supposed to be due to the orbital hybridizations induced by In filler. It was found that the In filler made the [Sb(4)](4-) rings become bigger and squarer because of an electron transition from Sb to In brought out by the orbital hybridization between In and Sb and that the Ba filler caused the [Sb(4)](4-) rings to get smaller and squarer because of a reverse electron transition from Ba to Sb induced by a large difference in electronegativities between Ba and Sb. A model of how to form the rectangular [Sb(4)](4-) ring is presented, and the five chemical states of Sb in CoSb(3) are reasonably assigned to different chemical bonds in the model.

5.
Hepatobiliary Pancreat Dis Int ; 8(4): 397-401, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19666409

RESUMO

BACKGROUND: Based on differences in the virus nucleotide sequence, hepatitis B virus (HBV) genotypes are presently divided into genotypes A-H. The geographic distributions of HBV genotypes differ in countries and regions. To determine the general characteristics of their distributions in the mainland of China, we reviewed articles on HBV genotypes published in China. METHODS: The Wanfang Database and the CNKI Database were searched for original articles involving HBV in China, and then the data from the articles were classified according to genotype and latitude and analyzed using SPSS 11.0. RESULTS: The main HBV genotypes were C, B and BC, and their rates were 50.99%, 35.58%, 6.07%, respectively; other genotypes were rare. There was a negative correlation between latitude and the rate of genotype B (r=-0.782, P<0.01), while a positive correlation existed between latitude and the rate of genotype C (r=0.646, P<0.01). No correlation was observed between latitude and the rates of other genotypes (r=0.294, P>0.05). CONCLUSIONS: In China, HBV genotype C predominates, followed by genotype C and mixed genotype BC; genotypes A, D and others are rare. With an increasing latitude, the distribution of genotype B decreases gradually, while that of genotype C tends to increase. The other genotypes do not show any changes.


Assuntos
Povo Asiático/estatística & dados numéricos , Vírus da Hepatite B/genética , Hepatite B/etnologia , China/epidemiologia , Genótipo , Humanos , Características de Residência
6.
J Phys Chem B ; 110(42): 20823-8, 2006 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17048893

RESUMO

Iodine-doped (I-doped) mesoporous titania with a bicrystalline (anatase and rutile) framework was synthesized by a two-step template hydrothermal synthesis route. I-doped titania with anatase structure was also synthesized without the use of a block copolymer as a template. The resultant titania samples were characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared, nitrogen adsorption, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-visible absorption spectroscopy. Both I-doped titania samples, with and without template, show much better photocatalytic activity than commercial P25 titania in the photodegradation of methylene blue under the irradiation of visible light (>420 nm) and UV-visible light. Furthermore, I-doped mesoporous titania with a bicrystalline framework exhibits better activity than I-doped titania with anatase structure. The effect of rutile phase in titania on the adsorptive capacity of water and surface hydroxyl, and photocatalytic activity was investigated in detail. The excellent performance of I-doped mesoporous titania under both visible light and UV-visible light can be attributed to the combined effects of bicrystalline framework, high crystallinity, large surface area, mesoporous structure, and high visible light absorption induced by I-doping.

7.
Materials (Basel) ; 9(12)2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-28774127

RESUMO

It is difficult to realize flame retardancy of epoxy without suffering much detriment in thermal stability. To solve the problem, a super-efficient phosphorus-nitrogen-containing reactive-type flame retardant, 10-(hydroxy(4-hydroxyphenyl)methyl)-5,10-dihydrophenophosphazinine-10-oxide (HB-DPPA) is synthesized and characterized. When it is used as a co-curing agent of 4,4'-methylenedianiline (DDM) for curing diglycidyl ether of bisphenol A (DGEBA), the cured epoxy achieves UL-94 V-0 rating with the limiting oxygen index of 29.3%. In this case, the phosphorus content in the system is exceptionally low (0.18 wt %). To the best of our knowledge, it currently has the highest efficiency among similar epoxy systems. Such excellent flame retardancy originates from the exclusive chemical structure of the phenophosphazine moiety, in which the phosphorus element is stabilized by the two adjacent aromatic rings. The action in the condensed phase is enhanced and followed by pressurization of the pyrolytic gases that induces the blowing-out effect during combustion. The cone calorimeter result reveals the formation of a unique intumescent char structure with five discernible layers. Owing to the super-efficient flame retardancy and the rigid molecular structure of HB-DPPA, the flame-retardant epoxy acquires high thermal stability and its initial decomposition temperature only decreases by 4.6 °C as compared with the unmodified one.

8.
Int J Clin Exp Med ; 8(4): 6129-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131216

RESUMO

Pseudomonas aeruginosa (PA) plays plays an important role in nosocomial infection. To explore the heteroresistance of PA to imipenem (IMP), we detected the sensitivity of 140 strains of PA to IMP using the KB method and VITEK method. Combined with resistance mutation analysis, the heteroresistance of PA to IMP was determined. Whilst, the double disk synergy test and SYBGreen RT-PCR for efflux pump were performed in IMP-heteroresistant PA strains. In this study, we confirmed 20 IMP-heteroresistant strains. The double disk synergy tests suggested that none of 20 heteroresistant PA strains produced metalloenzyme. The SYBGreen quantitative RT-PCR revealed that the MexAB expression level of efflux pump in IMP-heteroresistant PA was significantly higher than that in the IMP-sensitive strains (P<0.05), while there was no significantly different between the MexCD expression between resistant strains and sensitive strains (P<0.05). We believe that the clinicians should pay more attention to the PA heteroresistance to IMP, and the heteroesistance of PA to IMP is related to high expression in the MexAB of PA efflux pump.

9.
PLoS One ; 8(12): e83123, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24349444

RESUMO

BACKGROUND: Huangqi injection is derived from Astragalus membranaceus root. In China, recent reports of Huangqi injection for the treatment of leucopenia have emerged. However, a systematic review of these reports has not been performed. Thus, we conducted a meta-analysis of clinical controlled trials to assess the clinical value of Huangqi injection in the treatment of leucopenia. METHODS: We searched the Chinese Biomedical Literature Database (CBM), Wanfang Database, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Full-text Database (VIP), as well as PubMed and EMBASE to collect the data about trials of Huangqi injection for treating leucopenia. A meta-analysis was performed using RevMan 5.2 software. RESULTS: A total of 13 studies involving 841 patients were included in this study. The overall study quality was lower according to the Jadad scale. The meta-analysis showed that experimentally treated patients experienced greater therapeutic efficacy and lower white blood cell counts than control groups treated with Western medicine (P < 0.05). No publication bias was evident, according to Egger's test. CONCLUSIONS: The validity of this meta-analysis was limited by the overall poor quality of the included studies. Huangqi injection may have potential clinical value in the treatment of leucopenia, but confirmation with rigorously well-designed multi-center trials is needed.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Leucopenia/tratamento farmacológico , Ensaios Clínicos como Assunto , Feminino , Humanos , Contagem de Leucócitos , Leucopenia/sangue , Masculino , PubMed
10.
Artigo em Inglês | MEDLINE | ID: mdl-24069058

RESUMO

Objective. To evaluate the clinical value of Danshen injection and Huangqi injection for the treatment of liver cirrhosis. Methods. The Chinese Biomedical Literature Database (CBM), Chinese Scientific Journals Full-Text Database (VIP), Wanfang Database, China National Knowledge Infrastructure (CNKI), PubMed, and EMBASE database were searched to collect the literatures about the randomized controlled trials involving the treatment of liver cirrhosis with Danshen injection combined with Huangqi injection, and the data analyses were performed using RevMan 4.2 software. Results. A total of 11 studies involving 1086 patients (trials group: 554 cases, control group: 532 cases) were included in this study. Compared with those in control group, the meta-analysis showed-that the total effectiveness rate and the level of serum albumin increased, while serum total bilirubin, alanine transmninase, type III procollagen, hyaluronic acid, laminin, and type-IV collagen decreased in trials group. The Jadad score ranged from 1 to 2 and the funnel plot analysis suggests that publication bias may occur. Conclusions. Danshen injection combined with Huangqi injection may promote the curative efficacy of liver cirrhosis, which is a promising novel treatment approach. The exact outcome needs to perform rigorously designed, multicenter, and large randomized controlled trials.

11.
PLoS One ; 7(5): e36294, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22570701

RESUMO

BACKGROUND: Previous studies indicated that oral squamous cell carcinomas (OSCC) might be related to human papilloma virus (HPV) infection. However, up to now, there still lacks a large sample study to analyze the relationship between OSCC in a Chinese population and oral HPV infection. In the present study, we used a meta-analysis to evaluate the relationship of OSCC with HPV infection in a Chinese population. METHODS: The reports on HPV and OSCC in a Chinese population published between January, 1994, and September, 2011 were retrieved via CNKI/WANFANG/OVID/MEDLINE databases. According to the inclusion criteria, we selected 18 eligible case-control studies. After testing the heterogeneity of the studies by the Cochran Q test, the meta-analyses for HPV and HPV16 were performed using the fixed effects model. RESULTS: The overall positive rates of HPV and HPV16 in OSCC were 58.0% (354/610; 95% confidence interval [CI], 54.1-61.9) and 47.47% (169/356; 95% CI: 42.3-52.7), respectively; which were significantly higher than those in normal controls 10.44% (26/249; 95% CI: 7.2-14.7) and 7.1% (13/182; 95% CI: 4.2-11.8). Quantitative meta-analysis revealed that, compared with normal controls, the combined odds ratios of OSCC with HPV or HPV16 infection were 12.7 (95% CI: 8.0-20.0) and 9.0 (95% CI: 5.1-15.6), respectively. Both Begg's test and funnel plots revealed that no publication bias was found in this present study (P>0.05). CONCLUSIONS: High incidences of HPV infection (mainly involving HPV16) were found in the samples of Chinese OSCC. For the Chinese population, HPV infection elevates the risk of OSCC tumorigenesis. Prophylactic HPV-vaccination may reduce the burden of HPV-related OSCC in China.


Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias Bucais/virologia , Infecções por Papillomavirus/virologia , Povo Asiático/estatística & dados numéricos , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , Transformação Celular Viral , China/epidemiologia , Papillomavirus Humano 16/fisiologia , Humanos , Incidência , Neoplasias Bucais/epidemiologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Prevalência
12.
Artigo em Inglês | MEDLINE | ID: mdl-22565456

RESUMO

BACKGROUND: Previous studies have confirmed that the presence of Ureaplasma urealyticum (UU) and Mycoplasma hominis (MH) increases the risks of various diseases including genital infections in women. Hence, the surveillance policies for the prevalence and antimicrobial susceptibility of UU and MH are important for both the prevention and the treatment of the diseases associated with genital mycoplasmas. AIM: The objective of this study is to investigate the characteristics of UU and MH prevalence and its antimicrobial susceptibility in Chinese women with genital infection. METHODS: By using commercial mycoplasma strips, we investigated the incidence and antimicrobial resistance of UU and MH in 3306 Chinese women with genital infection between January 2005 and December 2009 in Changzhou China. RESULTS: (1) The overall positive incidence of genital mycoplasmas was 62.16%. The most common pattern was UU monoinfection (46.52%), the UU-MH coinfection pattern ranked second (13.91%) and MH monoinfection was lowest (1.71%). According to annual analysis, MH infection revealed an increasing trend between 2005 and 2009. However, a significantly higher infection rate by genital mycoplasmas was found in young women (age range: 16-35 years). (2) Overall, MH susceptibility rates remained high only to doxycycline (DOX), minocycline (MIN) and josamycin (JOS), while UU had high susceptibility rates only to DOX, MIN and clarithromycin (CLA). The resistance rates of UU-MH-mixed isolates to most of drugs were significantly higher than those of UU- or MH-single isolates. CONCLUSIONS: High infection rates and severe drug resistances of genital mycoplasmas were found in Chinese women with genital infections. The laboratory screening and antimicrobial susceptibility testing for genital mycoplasmas is vital to treat the infection.


Assuntos
Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/epidemiologia , Mycoplasma hominis/efeitos dos fármacos , Infecções por Ureaplasma/tratamento farmacológico , Infecções por Ureaplasma/epidemiologia , Ureaplasma urealyticum/efeitos dos fármacos , Adolescente , Adulto , Distribuição por Idade , Idoso , Antibacterianos/uso terapêutico , Povo Asiático , China/epidemiologia , Farmacorresistência Bacteriana , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Infecções do Sistema Genital/tratamento farmacológico , Infecções do Sistema Genital/epidemiologia , Adulto Jovem
13.
Exp Ther Med ; 1(1): 113-120, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23136603

RESUMO

The aim of this study was to investigate possible differences in cellular immunity between chemo- and/or radiotherapy groups during a long interval after surgery in esophageal squamous cell carcinoma (ESCC) patients. Cellular immunity was assessed as peripheral lymphocyte subsets in response to chemotherapy (CT), radiotherapy (RT) and CT+RT by flow cytometric analysis. There were 139 blood samples obtained at different time points relative to surgery from 73 patients with ESCC. The changes in the absolute and relative proportions of lymphocyte phenotypes were significant among the adjuvant therapy groups. There were significant differences in the absolute counts of CD4(+) and CD8(+) T cells among the interval groups, and a lower CD4/CD8 ratio was found in patients following a prolonged interval. RT alone had a profound effect on the absolute counts of CD3(+), CD4(+) and CD8(+) T cells compared with the other groups. CD4(+) T cells exhibited a decreasing trend during a long interval, leading to a prolonged T-cell imbalance after surgery. Univariate analysis revealed that the interaction of the type of adjuvant therapy and the interval after surgery was correlated only with the percentage of CD4(+) T cells. The percentage of CD4(+) T cells can be used as an indicator of the cellular immunity after surgery in ESCC patients. However, natural killer cells consistently remained suppressed in ESCC patients following adjuvant therapy after surgery. These findings confirm an interaction between adjuvant therapy and the interval after surgery on peripheral CD4(+) T cells, and implies that adjuvant therapy may have selective influence on the cellular immunity of ESCC patients after surgery.

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