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1.
Ann Clin Microbiol Antimicrob ; 21(1): 9, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35232448

RESUMO

BACKGROUND: Olsenella uli is anaerobic or microaerophilic bacteria, commonly found in oral cavity or gastrointestinal tract, which has not been reported to be associated with lower respiratory tract infection. Herein, we report the first case of Olsenella uli infection in the lung. CASE PRESENTATION: A 70-year-old male farmer with no history of other respiratory tract diseases developed a cough with bloody sputum three times a day without obvious causes or other concomitant symptoms. After a period of treatment with empirical antibiotic, his condition did not improve. The computed tomography (CT) and lung biopsy results indicated bilateral pneumonia, and Olsenella uli was identified by micromorphology, sequence analysis and mass spectrometry analysis recovered from sputum. Ceftazidime, a third generation cephalosporin was used for the treatment, and the patient recovered after 10 days. CONCLUSIONS: Our report suggests a causative role of gingival bacteria in the pathogenesis of pneumonia, thus early diagnosis and prompt antibiotic therapy may play a role in the treatment of Olsenella uli induced pneumonia.


Assuntos
Actinobacteria , Actinobacteria/genética , Idoso , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológico , RNA Ribossômico 16S
2.
Chemosphere ; 288(Pt 3): 132619, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34678352

RESUMO

Untreated wastewater containing fluoroquinolone antibiotics poses serious hazards to aquatic species and human health; therefore, treatment of waste expanded polystyrene (EPS) is a crucial environmental matter. In this study, waste EPS was modified with a H2SO4/biodegradable chelating agent, [S,S]-ethylenediamine-N,N'-disuccinic acid (EDDS), and used for highly efficient adsorption of the fluoroquinolone antibiotic ciprofloxacin. When ciprofloxacin of 25 mg/L was used, the H2SO4-modified EPS (EPSH2SO4) adsorbed 60.5% of the ciprofloxacin. During sulfonation, adding a low dose of EDDS markedly improved the adsorption ability of EPSH2SO4+EDDS. The optimal modification conditions were 95% H2SO4, 0.002 M EDDS, 80 °C, and 40 min. The increased adsorbent doses enhanced the adsorption. Approximately 0.2 g/L of EPSH2SO4+EDDS could effectively adsorb 97.8% of the ciprofloxacin (554.3 mg/g) within 30 min. Solution pH0 greatly influenced the adsorption, and the most suitable pH0 was 6. The Langmuir isotherm accurately described the adsorption behaviors of both EPSH2SO4 and EPSH2SO4+EDDS (R2 = 0.997-0.998). The adsorption ability of EPSH2SO4+EDDS (qmax = 1250 mg/g) was 32 times higher than that of EPSH2SO4 (qmax = 38.6 mg/g). A total of 1 M HCl effectively regenerated the exhausted adsorbent. The optimal solid/liquid ratio and time were 0.08 g/20 mL and 60 min, respectively. The regenerated EPSH2SO4+EDDS maintained a high adsorption ability (87.2%) after 10 regeneration cycles. The results thus indicate that the EPSH2SO4+EDDS adsorption-regeneration process is a potential approach to remove ciprofloxacin from water.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Adsorção , Antibacterianos , Quelantes , Fluoroquinolonas , Humanos , Águas Residuárias , Água
3.
Chemosphere ; 271: 129529, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33434822

RESUMO

Norfloxacin, a fluoroquinolone antibiotic, is widely used to treat microbial infections. However, untreated norfloxacin-containing wastewater poses serious threats to the ecosystem and human health. The treatment of waste expanded polystyrene (EPS) by landfilling or incineration could cause environmental problems. In this research, the feasibility of converting EPS into a valuable adsorbent for norfloxacin was evaluated. Results showed that EPS treated with H2SO4 (EPSH2SO4) effectively adsorbed norfloxacin. The optimal sulfonation conditions were 95% H2SO4 and 100 °C. Addition of 0.001 M of persulfate during sulfonation obviously shortened the sulfonation time to 7.5 min, and the adsorption ability of modified EPS increased with increasing persulfate dose. Under the experimental conditions of 25 mg L-1 norfloxacin, pH0 6.2, and 0.4 g L-1 EPSH2SO4+persulfate (dry weight), 97.2% of norfloxacin could be removed after 30 min of adsorption. The adsorption ability of EPSH2SO4+persulfate decreased with increasing solution pH0, and the optimal pH0 was 6.2. The Langmuir isotherm best described the adsorption behavior of EPSH2SO4+persulfate (qmax = 140.9 mg L-1, b = 1.97 L mg-1, R2 = 0.9992). 1 M HCl effectively regenerated the exhausted EPSH2SO4+persulfate at the optimal solid/solution ratio of 8 g L-1. EPSH2SO4+persulfate maintained excellent adsorption capacity (>80.9%) after eight adsorption-regeneration cycles.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Adsorção , Antibacterianos , Ecossistema , Fluoroquinolonas , Humanos , Concentração de Íons de Hidrogênio , Cinética , Águas Residuárias , Poluentes Químicos da Água/análise
4.
J Mater Chem B ; 8(42): 9679-9685, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-32985643

RESUMO

Rapid and reversible actuation and shape memory effects are critical for biomimetic soft actuators based on polymer hydrogels. However, most conventional hydrogel actuators show very slow actuation or deformation rates in water. It remains a challenge to realize rapid actuations, particularly for hydrogels to actuate in air. Here, a novel strategy to create diverse hydrogel devices with shape memory effects and rapid reversible actuations even in air was demonstrated. This strategy relies on a precise definition of local crosslinking by using multivalent metal ion coordination. This is demonstrated by infiltrating Fe3+ ions into stretchable nanocomposite polyacrylamide hydrogels with the amide groups converted into primary amine groups for multivalent coordination and crosslinking. The Fe3+ coordination with amine groups enhanced the crosslink density and modulus, leading to deswelling. By using an iron rod electrode, the Fe3+ coordination and crosslinking were precisely controlled to generate hydrogels with heterogeneous local crosslinking, including Janus hydrogels, S-shaped hydrogels, and cross-shaped hydrogel grippers. These soft devices were reversibly actuated in tens of seconds when cyclically dehydrated in ethanol and rehydrated in water. Most interestingly, very rapid reversible actuations of a hydrogel device in air were demonstrated by using electro-redox reaction of Fe3+ and Fe2+ in the hydrogel, where the reversible local coordination crosslinking and decomposition served as a hinge to actuate the hydrogel. This strategy based on reversible local coordination and crosslinking may open an avenue for rapid fabrication of hydrogel devices with well-defined structures and actuation properties.


Assuntos
Resinas Acrílicas/química , Complexos de Coordenação/química , Hidrogéis/química , Ferro/química , Nanocompostos/química , Reagentes de Ligações Cruzadas/química , Técnicas Eletroquímicas , Compostos Férricos/química
5.
J Chromatogr A ; 1461: 161-70, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27451260

RESUMO

Acetonitrile stacking is an online concentration method that is distinctive due to its inclusion of a high proportion of organic solvent in sample matrices. We previously designed a universal methodology for the combination of liquid-phase microextraction (LPME) and capillary electrophoresis (CE) using acetonitrile stacking and micellar electrokinetic chromatography (MEKC) mode, thereby achieving large-volume injection of the diluted LPME extractant and the online concentration. In this report, the methodology was extended to the analysis of highly substituted hydrophobic chlorophenols in wines using diethyl carbonate as the extractant. Additionally, the mechanism of acetonitrile stacking was studied. The results indicated that the combination of LPME and MEKC exhibited good analytical performance: with ∼40-fold concentration by LPME, a 20-cm (33% of the total length) sample plug injection of an eight-fold dilution of diethyl carbonate with the organic solvent-saline solution produced enrichments higher by a factor of 260-791. Limits of qualification ranged from 5.5 to 16.0ng/mL. Acceptable reproducibilities of lower than 1.8% for migration time and 8.6% for peak areas were obtained. A dual stacking mechanism of acetonitrile stacking was revealed, involving transient isotachophoresis plus pH-junction stacking. The latter was associated with a pH shift induced by the presence of acetonitrile. The pseudo-stationary phase (Brij-35) played an important role in reducing the CE running time by weakening the isotachophoretic migration of the analyte ions following Cl(-) ions. The combination of acetonitrile stacking and nonionic micelle-based MEKC appears to be a perfect match for introducing water-immiscible LPME extractants into an aqueous CE system and can thus significantly expand the application of LPME-CE in green analytical chemistry.


Assuntos
Acetonitrilas/química , Cromatografia Capilar Eletrocinética Micelar/métodos , Microextração em Fase Líquida/métodos , Clorofenóis/análise , Clorofenóis/química , Eletroforese Capilar/métodos , Polietilenoglicóis/química , Solventes/química , Água/química , Vinho/análise
6.
Se Pu ; 31(3): 254-9, 2013 Mar.
Artigo em Zh | MEDLINE | ID: mdl-23785998

RESUMO

A new method was established for the simultaneous determination of the migration amounts of bisphenol A (BPA) and phenol from polycarbonate (PC) bottles based on subcritical water extraction (SWE) and high performance liquid chromatography. The optimum extraction conditions included an extraction temperature of 120 degree C, a pressure of 6.89 MPa (1000 psi), a static extraction time of 1 h and one cycle. Under the conditions, the migration amounts of the BPA ranged from 6.81 to 1116 micro g/g in 11 samples. Phenol was not detectable in 5 samples, and in other ones the migration amounts of phenol varied in the range of 3.25 -6. 08 micro g/g. The traditional soaking extraction experiments showed that PC was subjected to weak hydrolysis after long-time leaching. The BPA and phenol were separated in 8 min. Good linearities were obtained in the range of 0. 05 - 20 mg/L for BPA and 0.02 - 20 mg/L for phenol ( r > 0.999 7). The limits of detection were 7.6 micro g/L for BPA and 2.0 micro g/L for phenol. Intra-day and inter-day repeatabilities (expressed as RSD) were less than 5.21% and 11.63%, respectively. Compared with traditional water soaking extraction, the extraction efficiencies increased 49 - 106 times using this developed SWE method. The procedure is simple, rapid and environment friendly, and can be utilized to determine the migration amounts of BPA and phenol in PC bottles.


Assuntos
Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Utensílios de Alimentação e Culinária , Água Potável/química , Fenóis/análise , Cimento de Policarboxilato/química , Estrogênios não Esteroides/análise , Microextração em Fase Líquida/métodos
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