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https://www.readbyqxmd.com/read/28342758/effects-of-low-frequency-ultrasound-on-heterogenous-deacetylation-of-chitin
#1
Ngo Thi Hoai Duong, Ngo Dang Nghia
The effects of low frequency ultrasound to the heterogeneous deacetylation of chitin from the shell of white shrimp (Penaeus vannamei) were examined. The deacetylation process was carried out in the range of NaOH concentrations from 35% to 65% (w/w) with and without the ultrasound in the frequency of 37kHz, RMS=300W. The chitosan obtained was characterized in the degree of deacetylation, solubility, FT-IR and X-ray diffraction. The results showed that the behaviors of the deacetylation in two cases, with and without ultrasound, were similar but the ultrasound enhanced the deacetylation rate and therefore reduced the time of the reaction to get the same degree of deacetylation...
March 22, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28335194/automatic-echographic-detection-of-halloysite-clay-nanotubes-in-a-low-concentration-range
#2
Francesco Conversano, Paola Pisani, Ernesto Casciaro, Marco Di Paola, Stefano Leporatti, Roberto Franchini, Alessandra Quarta, Giuseppe Gigli, Sergio Casciaro
Aim of this work was to investigate the automatic echographic detection of an experimental drug delivery agent, halloysite clay nanotubes (HNTs), by employing an innovative method based on advanced spectral analysis of the corresponding "raw" radiofrequency backscatter signals. Different HNT concentrations in a low range (5.5-66 × 10(10) part/mL, equivalent to 0.25-3.00 mg/mL) were dispersed in custom-designed tissue-mimicking phantoms and imaged through a clinically-available echographic device at a conventional ultrasound diagnostic frequency (10 MHz)...
April 11, 2016: Nanomaterials
https://www.readbyqxmd.com/read/28327075/magnetic-nanobubbles-with-potential-for-targeted-drug-delivery-and-trimodal-imaging-in-breast-cancer-an-in-vitro-study
#3
Weixiang Song, Yindeng Luo, Yajing Zhao, Xinjie Liu, Jiannong Zhao, Jie Luo, Qunxia Zhang, Haitao Ran, Zhigang Wang, Dajing Guo
AIM: The aim of this study was to improve tumor-targeted therapy for breast cancer by designing magnetic nanobubbles with the potential for targeted drug delivery and multimodal imaging. MATERIALS & METHODS: Herceptin-decorated and ultrasmall superparamagnetic iron oxide (USPIO)/paclitaxel (PTX)-embedded nanobubbles (PTX-USPIO-HER-NBs) were manufactured by combining a modified double-emulsion evaporation process with carbodiimide technique. PTX-USPIO-HER-NBs were examined for characterization, specific cell-targeting ability and multimodal imaging...
March 13, 2017: Nanomedicine
https://www.readbyqxmd.com/read/28326221/an-extremely-rare-case-of-lower-urinary-tract-symptoms-floating-benign-mesenchymal-mass-in-abdomen
#4
Bulent Kati, Yigit Akin, Eyyup Sabri Pelit, Mehmet Ogur Yilmaz
A 48-year-old man admitted to the urology outpatient clinic with major symptoms of right-side pain and intermittent lower urinary tract symptoms (LUTSs) such as low urine flow rate, dysuria, and frequency. Uroflowmetry showed low urine flow, and laboratory tests revealed no pathology. Ultrasound (US) showed a 7 cm calcific mass above the bladder and a kidney cyst with a diameter of 5.3 cm in the upper pole of the right kidney. Enhanced computed tomography confirmed the US findings. Laparoscopic transperitoneal renal cyst decortication was performed...
2017: Case Reports in Urology
https://www.readbyqxmd.com/read/28316942/piezosurgery-a-boon-for-modern-periodontics
#5
REVIEW
Mathai Thomas, Uttam Akula, Kranti K R Ealla, Nirosha Gajjada
Dentistry has undergone significant advancement and has seen several changing concepts over a decade. One such novel innovation is piezosurgery. Piezoelectric bone surgery or otherwise known as piezosurgery is a novel technique invented by Professor Vercellotti in 1988 to overcome the limitations of traditional instrumentation in oral bone surgery by modifying and improving conventional ultrasound technology. It is a promising, meticulous, and soft tissue sparing system for bone cutting based on low frequency ultrasonic microvibrations...
January 2017: Journal of International Society of Preventive & Community Dentistry
https://www.readbyqxmd.com/read/28306228/diagnosis-natural-history-and-management-in-vascular-ehlers-danlos-syndrome
#6
Peter H Byers, John Belmont, James Black, Julie De Backer, Michael Frank, Xavier Jeunemaitre, Diana Johnson, Melanie Pepin, Leema Robert, Lynn Sanders, Nigel Wheeldon
Vascular Ehlers Danlos syndrome (vEDS) is an uncommon genetic disorders characterized by arterial aneurysm, dissection and rupture, bowel rupture, and rupture of the gravid uterus. The frequency is estimated as 1/50,000-1/200,000 and results from pathogenic variants in COL3A1, which encodes the chains of type III procollagen, a major protein in vessel walls and hollow organs. Initial diagnosis depends on the recognitions of clinical features, including family history. Management is complex and requires multiple specialists who can respond to and manage the major complications...
March 2017: American Journal of Medical Genetics. Part C, Seminars in Medical Genetics
https://www.readbyqxmd.com/read/28287146/hydrogel-increases-localized-transport-regions-and-skin-permeability-during-low-frequency-ultrasound-treatment
#7
Tatiana Aparecida Pereira, Danielle Nishida Ramos, Renata F V Lopez
Low frequency ultrasound (LFU) enhances skin permeability via the formation of heterogeneous localized transport regions (LTRs). In this work, hydrogels with different zeta potentials were used as the coupling medium for LFU to investigate their contribution to LTR patterns and to the skin penetration of two model drugs, calcein and doxorubicin (DOX). When hydrogels were used, LTRs covering at least a 3-fold greater skin area were observed compared to those resulting from traditional LFU treatment and sodium lauryl sulfate...
March 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28283264/uterine-contractility-and-elastography-as-prognostic-factors%C3%A2-for-pregnancy-after-intrauterine-insemination
#8
Nelly Swierkowski-Blanchard, Florence Boitrelle, Laura Alter, Jacqueline Selva, Thibaud Quibel, Antoine Torre
OBJECTIVE: To determine the impact of the frequency and intensity of uterine contractions (UCs) at the time of IUI on subsequent fertility. DESIGN: Observational pilot study. SETTING: University hospital. PATIENT(S): One hundred volunteer women scheduled for IUI between April 2011 and July 2013, in whom UCs were assessed during the ultrasound before IUI. INTERVENTION(S): A two-dimensional sagittal uterus elastography was recorded for 5 minutes...
March 7, 2017: Fertility and Sterility
https://www.readbyqxmd.com/read/28276672/current-adoption-of-lung-ultrasound-in-intensive-care-units-an-italian-multi-centre-survey
#9
Italo Calamai, Massimiliano Greco, Guido Bertolini, Rosario Spina
BACKGROUND: Lung ultrasound (LUS) is a useful tool for assessing lung status in critically ill patients, but is not widely applied in intensive care units (ICUs). The aim of this study was to investigate the use of LUS in Italian ICUs. METHODS: A questionnaire was distributed to 116 ICU representatives belonging to the Italian GiViTI network, participating in a national project on continuous quality of care assessment. The answers to the questionnaire were analysed with the data collected in the course of said project...
March 7, 2017: Minerva Anestesiologica
https://www.readbyqxmd.com/read/28275563/neonatal-cranial-sonography-ultrasound-findings-in-neonatal-meningitis-a-pictorial-review
#10
REVIEW
Nishant Gupta, Hemal Grover, Itisha Bansal, Kusum Hooda, Joshua M Sapire, Rama Anand, Yogesh Kumar
Neonatal bacterial meningitis is a common manifestation of late onset neonatal sepsis. Cranial sonography (CRS) has a crucial role in assessment of infants with clinical suspicion of bacterial meningitis as well as follows up of its complications. CRS is performed with high frequency transducer through anterior fontanelle in both coronal and sagittal planes. Various sonographic findings range from echogenic and widened sulci, ventriculomegaly, ventriculitis, hydrocephalus, extra-axial fluid collections, cerebritis and brain abscess...
February 2017: Quantitative Imaging in Medicine and Surgery
https://www.readbyqxmd.com/read/28275304/subclinical-atherosclerosis-is-linked-to-small-intestinal-bacterial-overgrowth-via-vitamin-k2-dependent-mechanisms
#11
Francesca Romana Ponziani, Maurizio Pompili, Enrico Di Stasio, Maria Assunta Zocco, Antonio Gasbarrini, Roberto Flore
AIM: To assess the rate of matrix Gla-protein carboxylation in patients with small intestinal bacterial overgrowth (SIBO) and to decipher its association with subclinical atherosclerosis. METHODS: Patients with suspected SIBO who presented with a low risk for cardiovascular disease and showed no evidence of atherosclerotic plaques were included in the study. A glucose breath test was performed in order to confirm the diagnosis of SIBO and vascular assessment was carried out by ultrasound examination...
February 21, 2017: World Journal of Gastroenterology: WJG
https://www.readbyqxmd.com/read/28271874/highly-efficient-catalytic-hydrogen-evolution-from-ammonia-borane-using-the-synergistic-effect-of-crystallinity-and-size-of-noble-metal-free-nanoparticles-supported-by-porous-metal-organic-frameworks
#12
Penglong Liu, Xiaojun Gu, Kai Kang, Hao Zhang, Jia Cheng, Haiquan Su
A series of nonprecious metal nanoparticles (NPs) supported by metal-organic framework MIL-101 were synthesized using four methods and their catalytic performance on hydrogen evolution from ammonia borane (NH3BH3) was studied. The results showed that the crystalline Co NPs with size of 4.5-8.5 and 14.5-24.5 nm had low activities featuring the total turnover frequency (TOF) values of 9.9 and 4.5 molH2 molcat(-1) min(-1), respectively. In contrast, the amorphous Co NPs with size of 1.6-2.6 and 13.5-24.5 nm exhibited high activities featuring the total TOF values of 51...
March 15, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28269191/spectral-based-pneumonia-detection-tool-using-ultrasound-data-from-pediatric-populations
#13
O Zenteno, B Castaneda, R Lavarello
Pediatric Pneumonia is one of the principal causes of death by year on children under the age of five worldwide. The diagnosis is commonly made by clinical criteria with support from imaging tools like radiography. Lung ultrasound has been considered a low-cost and portable alternative for pneumonia imaging; however, interpretation is subjective and requires adequate training. In the present work, a pneumonia detection algorithm based on the measurement of the fundamental bandwidth downshift over depth of ultrasound radiofrequency (RF) signals is presented...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28268995/low-frequency-ultrasound-radiosensitization-and-therapy-response-monitoring-of-tumors-an-in-vivo-study
#14
Ali Sadeghi-Naini, Martin Stanisz, Hadi Tadayyon, Jaswinder Taank, Gregory J Czarnota
A new framework has been introduced in this paper for tumor radiosensitization and therapy response monitoring using low-frequency ultrasound. Human fibrosarcoma xenografts grown in severe combined immunodeficiency (SCID) mice (n = 108) were treated using ultrasound-stimulated microbubbles at various concentration and exposed to different doses of radiation. Low-frequency ultrasound radiofrequency (RF) data were acquired from tumors prior to and at different times after treatment. Quantitative ultrasound (QUS) techniques were applied to generate spectral parametric maps of tumors...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28260297/-effects-of-low-frequency-pulsed-wave-ultrasound-on-the-shear-properties-of-the-interface-of-vancomycin-loaded-acrylic-bone-cement-stem
#15
Q H Zhao, F B Zhu, X Z Cai, S G Yan, R X He
Objective: To investigate the effects of low-frequency pulsed wave ultrasound on the shear properties of interface of the vancomycin -loaded acrylic bone cement-stem. Methods: The interfaces of 1% vancomycin-loaded acrylic bone cement-stem specimences were successfully manufactured and randomly divided into three groups: the control group, 450 mW/cm(2) ultrasound group and 1 200 mW/cm(2) ultrasound group, each group consisted of eight samples.Two ultrasound groups were exposed to a local ultrasonic field for 7 d, then immersed in PBS for 23 d, and the control groups were immersed in PBS for 30 d...
February 21, 2017: Zhonghua Yi Xue za Zhi [Chinese medical journal]
https://www.readbyqxmd.com/read/28254563/forward-models-for-extending-the-mechanical-damage-evaluation-capability-of-resonant-ultrasound-spectroscopy
#16
B R Goodlet, C J Torbet, E J Biedermann, L M Jauriqui, J C Aldrin, T M Pollock
Finite element (FE) modeling has been coupled with resonant ultrasound spectroscopy (RUS) for nondestructive evaluation (NDE) of high temperature damage induced by mechanical loading. Forward FE models predict mode-specific changes in resonance frequencies (ΔfR), inform RUS measurements of mode-type, and identify diagnostic resonance modes sensitive to individual or multiple concurrent damage mechanisms. The magnitude of modeled ΔfR correlate very well with the magnitude of measured ΔfR from RUS, affording quantitative assessments of damage...
February 8, 2017: Ultrasonics
https://www.readbyqxmd.com/read/28254284/novel-ultrasound-responsive-chitosan-perfluorohexane-nanodroplets-for-image-guided-smart-delivery-of-an-anticancer-agent-curcumin
#17
Fatemeh Baghbani, Mahdieh Chegeni, Fathollah Moztarzadeh, Samaneh Hadian-Ghazvini, Majid Raz
Ultrasound-responsive nanodroplets are a class of new emerging smart drug delivery systems which provide image-guided nano-therapy of various diseases, especially cancers. Here, we developed multifunctional smart curcumin-loaded chitosan/perfluorohexane nanodroplets for contrast-ultrasound imaging and on-demand drug delivery. The nanodroplets were synthesized via nanoemulsion process. The optimal formulation with the size of 101.2nm and 77.8% curcumin entrapment was chosen for release study and cytotoxicity evaluation...
May 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28253686/analysis-of-acoustic-impedance-matching-in-dual-band-ultrasound-transducers
#18
Ola Finneng Myhre, Tonni Franke Johansen, Bjørn Atle Johan Angelsen
Dual-frequency band probes are needed for ultrasound (US) reverberation suppression and are useful for image-guided US therapy. A challenge is to design transducer stacks that achieve high bandwidth and efficiency at both operating frequencies when the frequencies are widely separated with a frequency ratio ∼6:1-20:1. This paper studies the loading and backing conditions of transducers in such stacks. Three stack configurations are presented and analyzed using one-dimensional models. It is shown that a configuration with three layers of material separating the transducers is favorable, as it reduces high frequency ringing by ∼20 dB compared to other designs, and matches the low frequency (LF) transducer to the load at a lower frequency...
February 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28253670/in-vivo-ultrasonic-attenuation-in-cetacean-soft-tissues
#19
Michael D Gray, Peter H Rogers
In vivo ultrasonic attenuation was estimated for extracranial soft tissues of two Tursiops truncatus and one Delphinapterus leucas. Backscatter data was non-invasively collected as part of routine health-based ultrasound examinations using a transducer operating in the 1.6-3.7 MHz frequency range. Data collected over the proximal mandible and temporal regions was processed to yield attenuation estimates using a reference tissue phantom whose properties had been independently determined. The estimated attenuations were at the low end of the range of literature-reported values for mammalian fatty and connective tissues...
February 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28236581/single-simultaneous-and-sequential-applications-of-ultrasonic-frequencies-for-the-elimination-of-ibuprofen-in-water
#20
Asu Ziylan-Yavas, Nilsun H Ince
The study is about the assessment of single and multi-frequency operations for the overall degradation of a widely consumed analgesic pharmaceutical-ibuprofen (IBP). The selected frequencies were in the range of 20-1130kHz emissions coming from probes, baths and piezo-electric transducers attached to plate-type devices. Multi-frequency operations were applied either simultaneously as "duals", or sequentially at fixed time intervals; and the total reaction time in all operations was 30-min. The work also covers evaluation of the effect of zero-valent iron (ZVI) on the efficiency of the degradation process and the performance of the reaction systems...
January 26, 2017: Ultrasonics Sonochemistry
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