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1.
Turk J Chem ; 46(3): 835-848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37720626

RESUMO

In this study, ferrihydrite/ultrasound (US) system was used to activate peroxymonosulfate (PMS) to treat humic acid (HA) in artificial aqueous. The physical and chemical properties of ferrihydrite were characterized using SEM, zeta potential, BET, XRD, FTIR, and XPS analysis. A series of experiments were conducted to evaluate the effect of various factor on HA removal, including dosage of ferrihydrite, PMS concentration and pH value. The combination uses of US and ferrihydrite had obvious synergistic effect for HA removal. Under ferrihydrite/US/PMS system, nonthermal effect of US played the main role for HA removal. According to the result of radical quenching experiment, 1O2 was identified as the main reactive oxidative species (ROS) which contributed to HA removal. The study indicates ferrihydrite/US/PMS system is promising strategy for treatment of natural organic pollutant.

2.
Muscle Nerve ; 64(5): 594-599, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34396547

RESUMO

INTRODUCTION/AIMS: Intrathecal nusinersen administration can be challenging in certain adult spinal muscular atrophy (SMA) patients with difficult spinal anatomy who require imaging techniques (fluoroscopy or computed tomography scans) or invasive approaches (catheter placement, laminotomy) to identify the intrathecal space. We used ultrasound (US) assistance to access the lumbar intrathecal space in patients with SMA who experienced previous difficulties or failures with intrathecal dosing. METHODS: Eighteen adult patients with difficult spines were enrolled. We used US assistance, and we recorded the successful administrations, number of attempts, procedure times, and "patient satisfaction." RESULTS: There were 57 consecutive successful nusinersen spinal administrations in all patients enrolled. In 50% of patients, two or fewer attempts were needed to obtain a successful administration, with four or fewer attempts in 83.3%; only three patients reported more than four attempts because of both severe scoliosis and severe spine rotation (two patients) and obesity (one patient). The mean procedure time was 11.8 min (range, 1.7-28.9). Patient satisfaction was 4.97/5 (range, 4-5; median, 5) on Likert scale at 5 min and at 72 h. No major adverse events were reported, and two post dural puncture headaches were managed with medical therapy and with complete resolution within 72 h. DISCUSSION: US assistance seems to be a valid option among treatment choices for intrathecal nusinersen administration in patients with difficult spine. The absence of radiation exposure and the lack of need for intravenous sedation or general anesthesia are additional potential advantages to US assisted administration.


Assuntos
Atrofia Muscular Espinal , Oligonucleotídeos , Adulto , Humanos , Injeções Espinhais/métodos , Região Lombossacral , Atrofia Muscular Espinal/diagnóstico por imagem , Atrofia Muscular Espinal/tratamento farmacológico , Oligonucleotídeos/uso terapêutico , Ultrassonografia
3.
Ultrason Sonochem ; 75: 105606, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34058635

RESUMO

A commercial immobilized lipase was successfully used for the synthesis of five xylityl acyl esters by means of the esterification of free fatty acids (caprylic, capric, lauric and myristic, respectively) with xylitol under solvent-free conditions. Ultrasound-assistance was shown to be a key tool to overcome the handicap imposed by both the mutual immiscibility of fatty acids and xylitol substrates, and the semisolid character of the initial reaction mixtures. In such semisolid systems, ultrasonic irradiation may enable the transport of substrate molecules to the enzyme catalytic-site, leading to the efficient synthesis of xylityl fatty ester (e.g. up to 95% yield after 90 min at 40 °C), with xylityl monoacyl ester and xylitol diacyl ester appearing as the main products (greater than 96%), assessed by HPLC and NMR analyses. The separation of products was carried out by heating and simple centrifugation of the reaction medium, which was possible due to different densities of the resulting fractions.


Assuntos
Enzimas Imobilizadas/metabolismo , Ésteres/química , Ésteres/síntese química , Ácidos Graxos/química , Ondas Ultrassônicas , Xilitol/química , Biocatálise , Técnicas de Química Sintética
4.
Food Chem ; 345: 128862, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33338838

RESUMO

Effects of ultrasound-assisted chitooligosaccharides (COS-UA) coating on the quality attributes and microbial composition of refrigerated grass carp fillets were evaluated. The results showed that COS and COS-UA coatings retarded quality deterioration of fillets during storage. Compared to COS coatings, COS-UA treated samples had lower contents of BAs, simultaneously their levels of total volatile base nitrogen (TVB-N), K value and total viable counts (TVC) were further decreased by 13.6%, 4.2% and 7.8% on day 12, respectively. High-throughput sequencing showed that Aeromonas and Shewanella increased rapidly in control samples and became the main microbiota at day 12. By contrast, both coatings changed the microbial composition and reduced the proportion of spoilage organisms. Based on multiple evaluations, COS-UA extended shelf life of fillets by another 2 days when compared to COS. Therefore, ultrasonic treatment could be considered as an effective supplementary to improve the preservation effect of COS-based coatings for fresh preprocessed fish.


Assuntos
Carpas , Conservação de Alimentos/métodos , Armazenamento de Alimentos/métodos , Alimentos Marinhos , Ondas Ultrassônicas , Animais , Carpas/microbiologia , Microbiota
5.
Ultrason Sonochem ; 60: 104765, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31539728

RESUMO

Burning of coal accounts for an enormous proportion of the current energy supply, especially in developing countries. Burning of coal produces large amounts of coal fly ash, which causes serious environmental problems unless it is managed properly. Using chemical analysis, we found that coal fly ash could be a promising source of Si, Al, Ca and some rare earth elements, especially with the assistance of some measures such as ultrasound. In this study, we extracted silicon from coal fly ash using an alkaline dissolution strategy and investigated the effects of temperature and ultrasonic power on the efficiency of silicon extraction. During a 70 min reaction, the efficiency of silicon extraction increased markedly, from 9.41% to 34.96%, as the reaction temperature increased from 70 °C to 110 °C. With ultrasound assistance, ultrasonic waves enhanced the extraction of silicon at both 80 °C and 110 °C at 720 W ultrasound, increasing the efficiency of silicon extraction from 6.01% to 15.36% and from 34.96% to 54.42%, respectively. However, at 900 W ultrasonic power, extraction was slightly inhibited at both temperatures, causing a little decrease in efficiency.

6.
Int J Comput Assist Radiol Surg ; 12(12): 2205-2215, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28779275

RESUMO

PURPOSE: We present a novel augmented reality (AR) surgical navigation system based on ultrasound-assisted registration for pedicle screw placement. This system provides the clinically desired targeting accuracy and reduces radiation exposure. METHODS: Ultrasound (US) is used to perform registration between preoperative computed tomography (CT) images and patient, and the registration is performed by least-squares fitting of these two three-dimensional (3D) point sets of anatomical landmarks taken from US and CT images. An integral videography overlay device is calibrated to accurately display naked-eye 3D images for surgical navigation. We use a 3.0-mm Kirschner wire (K-wire) instead of a pedicle screw in this study, and the K-wire is calibrated to obtain its orientation and tip location. Based on the above registration and calibration, naked-eye 3D images of the planning path and the spine are superimposed onto patient in situ using our AR navigation system. Simultaneously, a 3D image of the K-wire is overlaid accurately on the real one to guide the insertion procedure. The targeting accuracy is evaluated postoperatively by performing a CT scan. RESULTS: An agar phantom experiment was performed. Eight K-wires were inserted successfully after US-assisted registration, and the mean targeting error and angle error were 3.35 mm and [Formula: see text], respectively. Furthermore, an additional sheep cadaver experiment was performed. Four K-wires were inserted successfully. The mean targeting error was 3.79 mm and the mean angle error was [Formula: see text], and US-assisted registration yielded better targeting results than skin markers-based registration (targeting errors: 2.41 vs. 5.18 mm, angle errors: [Formula: see text] vs. [Formula: see text]. CONCLUSION: Experimental outcomes demonstrate that the proposed navigation system has acceptable targeting accuracy. In particular, the proposed navigation method reduces repeated radiation exposure to the patient and surgeons. Therefore, it has promising prospects for clinical use.


Assuntos
Imageamento Tridimensional , Parafusos Pediculares , Imagens de Fantasmas , Coluna Vertebral/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Humanos , Projetos Piloto , Coluna Vertebral/cirurgia
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