Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology. / Pulsed Ultrasound Velocimetry combined with Pressure Difference (PUV+PD) measurement is a non-invasive in-line rheometric technique which is used to analyse the complex flow properties of industrial fluids for quality control purposes. Cape Peninsula University of Technology (CPUT) and Technical Research Institute of Sweden (SP) have developed and patented a new PUV+PD based system, called Flow-Viz™. Despite this advancement, the system and ultrasound sensor technology have not been fully tested and evaluated in a wide range of industrial fluids. Acoustic characterisation tests were carried out at SP, with the aim of understanding the ultrasound beam properties after propagating through industrial stainless steel (316L) pipe walls. For these tests, a high-precision robotic XYZ-scanner and needle hydrophone setup were used. Different ultrasound sensor configurations were mounted to a stainless steel pipe while using different coupling media between the transducer-to-wedge and sensor wedge-to-pipe boundaries. The ultrasound beam propagation after the wall interface was measured by navigating the needle hydrophone within a predefined 2-dimensional spatial grid. The most suitable coupling material was determined from the acoustic characterisation, and then used in the in-line rheological characterisation tests to evaluate the performance of the Flow-VizTM rheometric unit against conventional tube viscometry. The in-line rheological tests were conducted with bentonite, kaolin and Carboxymethyl cellulose (CMC) model fluids. The flow loop used consisted of three different pipe test sections; and two concentrations of each fluid were tested in order to ascertain the consistency of the measurements. The in-line rheological tests showed good agreement (±15%) between the two techniques and Flow-VizTM was able to provide important data at very low shear rates. Acoustic characterisation indicated that variations in the beam properties were highly dependent on the acoustic couplants used to mount the sensors to the stainless steel pipes. Furthermore, the in-line results showed the effectiveness of Flow-VizTM as an industrial rheometer. The non-invasive ultrasound sensor technology, was for the first time acoustically characterised through stainless steel. This information will now be used to further optimise the unique technology for advanced industrial applications, e.g. oil drilling fields, complex cement grout and food processing applications.

Esta investigação experimental teve como finalidade de avaliar os efeitos do ultra-som pulsado de baixa intensidade sobre a regeneração do miométrio e do endométrio de ratas submetidas à uterotomia. Foram utilizadas neste experimento 20 ratas adultas da raça Wistar, submetidas a uma uterotomia mediante incisão longitudinal de 1,5 cm total de uma das paredes do corno uterino. As ratas foram divididas em 2 grupos de 10 animais cada, sendo que um grupo foi submetido à estimulação ultra-sônica por 10 dias durante 15 minutos diários e outro grupo, chamado controle, foi submetido à estimulação fictícia pelo mesmo tempo e período. Seis horas antes do sacrifício, os animais receberam via intramuscular 0,10 mg de colchicina para cada 100 g de peso corporal com a finalidade de bloquear as mitoses em metáfase. A avaliação dos tecidos baseou-se na análise comparativa entre a contagem de células em mitose do endométrio e do miométrio de animais estimulados com o de animais controle. Os achados morfológicos foram analisados estatisticamente e são sugestivos de que o U.S.P. estimula a regeneração do miométrio bem como do endométrio de ratas. / This experimental investigation had the purpose to evaluate the low-intensity pulsed ultrasound effects under the regeneration of the myometrium and the endometrium of the rats that were submitted to uterotomia. It was used, in this experiment, twenty adult rats of the Wistar race, submitted to uterotomia beyond the longitudinal incision of total 1, 5 cm of one of the uterine horn walls. The rats were divided in two groups of ten animals each, the first group went trough fifteen daily minutes ultra-sound stimulation during ten days, and the second group, called control, went through fictional stimulation by the same time and period of the first group. Six hours before the sacrifice, the animals received, by intra muscular, 0, 10 mg of colchicine for each 100 g of body weight, with the intention to block the mitosis in metaphase. The evaluation of the tissue was based on the comparative analysis between the mitosis cell count of the stimulated animals\' endometric tissue and the control animals\' one. The morphologic findings were statistically analyzed.

Estudo dos efeitos da irradiação ultra-sônica pulsada de baixa intensidade sobre o desenvolvimento de segmentos da coluna vertebral implantados em camundongos isogênicos / The aim of the present research was evaluate the action of low-intensity pulsed ultrasonic irradiation on development and ossification of vertebral column blastemas, through mice new born tail segments implants in adult receptor isogenic mice lineages C57BL/6 and Balb/C. New born tail segments were implanted in subcutaneous tissues of adults isogenics mice C57BL/6 and intramuscularly in adults isogenics mice Balb/C. After 24 hours the implant, the animals in both groups, were stimulated with the low-intensity pulsed ultrasound (LIPUS), 10 minutes per day. After 5 days of stimulus, the receptors animals were death and had the implanted tails removed for histopathology, trhrough Periodic Acid Schiff plus Alcian Blue (PAS/AB), Masson's tricomico and hem lumen-eosin (HE). The group of animals stimulated which received subcutaneous implant presented the implant with accelerated in inter-vertebral diks, faces to chondrocytes organization and chondroblastes findings in cartilaginous matrix, showing maturity in fiber cartilages arrangements. It was observed too, a collagen fibers enlargement in the disks fibro cartilage which show more dense next the pulposo nucleus in the segments implanted and stimulated, compared with the controls segments. The areas of the segments were available by Fisher's test and Student's t. It didn't watch significant differences in the vertebral bodies' areas sizes in the animals which implant was subcutaneous (p'< OU = '0.05). In the intramuscular implants animals group, it was observed a major velocity in the hialuronic acid matrix formation in the intervertebral disks after LIPUS stimulus. Moreover, the fibrous ring fiber cartilages' were better organized with large number of cells inside the cartilaginous matrix compared with the controls segments. With regard to the vertebral bodies in the intramuscular implants, it's not verifies significant increases in the areas (p'< OU =' 0,05). The findings allow conclude that LIPUS should promote the ontogenetic differentation of the structural components of the mice vertebral column more quickly, trhough vertebras endochondral ossification microscopic evaluation and the inter-vertebral disks components differentiation, follow the methodology employed.

As qualidades biofísicas do U.S.P. levaram-nos a estimar o efeito do mesmo sobre a regeneração de um nervo periférico. Este estudo foi levado a efeito sobre a axotomia experimental do nervo ciático de ratos. Para tal finalidade estimulamos por 12 dias consecutivos, durante 20 minutos o coto proximal dos nervos axotomizados. A morfologia foi avaliada comparativamente entre cortes semifinos corados pelo azul de toluidina e cortes ultra finos à microscopia eletrônica, dos cotos proximais de nervos estimulados e não estimulados. A avaliação morfométrica das estruturas, baseou-se na contagem diferencial das fibras; da espessura da bainha de mielina e da área dos axônios das fibras tipo A, mediante o emprego de um software especializado ( Image Tool). Os achados morfológicos e a análise estatística dos dados morfométricos são altamente sugestivos de que o U.S.P. estimula a regeneração de nervos periféricos. / The biophysical qualities of pulsed ultrasound led us to appraise it¢s effect on the regeneration of a peripheral nerve. In this study our intention was to evaluate the effects of pulsed ultrasound on the axotomy of the ciatic nerve in rats. The proximal stump of the nerve was stimulated on 12 consecutive days with pulsed ultrasound and the effects of the sonication were evaluated through morphologic and morphometric techniques. Our findings suggest that sonication leads to a rapid regeneration of the nerve after axotomization. These affirmations are based on the counting of different types of fibre components in mixed nerves and the morphologic recovery of the same in comparasion with nerves of animals submitted to sham operation.

Pulsed ultrasound Doppler velocimetry proved to be capable of measuring velocities accurately (relative error less than 0.5 percent). In this research, the limitations of the method are investigated when measuring: in channels with a small thickness compared to the transducer diameter, at low velocities and in the presence of a flow reversal area. A review of the fundamentals of pulsed ultrasound Doppler velocimetry reveals that the accuracy of the measured velocity field mainly depends on the shape of the acoustic beam through the flow field and the intensity of the echo from the incident particles where the velocity is being measured. The ultrasonic transducer turned out to be most critical component of the system. Fundamental limitations of the method are identified. With ultrasonic beam measurements, the beam shape and echo intensity is further investigated. In general, the shape of the ultrasonic beam varies depending on the frequency and diameter of the emitter as well as the characteristics of the acoustic interface that the beam encounters. Moreover, the most promising transducer to measure velocity profiles in small channels is identified. Since the application of pulsed ultrasound Doppler velocimetry often involves the propagation of the ultrasonic burst through Plexiglas, the effect of Plexiglas walls on the measured velocity profile is analyzed and quantified in detail. The transducers ringing effect and the saturation region caused by highly absorbing acoustic interfaces are identified as limitations of the method. By comparing measurement results in the small rectangular channel to numerically calculated results, further limitations of the method are identified. It was not possible to determine velocities correctly throughout the whole channel at low flow rates, in small geometries and in the flow separation region. A discrepancy between the maximum measured velocity, velocity profile perturbations and incorrect velocity determination at the far channel wall were main shortcomings. Measurement results are improved by changes in the Doppler angle, the flow rate and the particle concentration. Suggestions to enhance the measurement system, especially its spatial resolution, and to further investigate acoustic wave interactions are made.

Submitted by Jaqueline Bastos (keca78@yahoo.com.br) on 2016-04-26T17:00:34Z No. of bitstreams: 1 TESE JAQUELINE S BASTOS - finalizando 180316.pdf: 13526973 bytes, checksum: d40891f9f50c56b18b4ee564f6453a39 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-28T17:50:25Z (GMT) No. of bitstreams: 1 bastos_js_dr_guara.pdf: 13526973 bytes, checksum: d40891f9f50c56b18b4ee564f6453a39 (MD5) / Made available in DSpace on 2016-04-28T17:50:25Z (GMT). No. of bitstreams: 1 bastos_js_dr_guara.pdf: 13526973 bytes, checksum: d40891f9f50c56b18b4ee564f6453a39 (MD5) Previous issue date: 2016-01-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo desse estudo in vivo foi verificar a resposta óssea de scaffolds porosos revestidos processados pela técnica de Sinterização Direta de Metais a laser (DMLS) associado à terapia de ultrassom de baixa intensidade. Os scaffolds foram processados empregando a técnica DMLS e tratados termicamente a 1000°C por 24 horas. Três tipos de tratamento de superfície foram avaliados: Alcalino, biomimético e imobilização de alendronato de sódio. Para o tratamento alcalino, as amostras foram imersas na solução de NaOH (5M) a 60ºC por 24 horas. O tratamento biomimético consistiu na imersão dos scaffolds em solução SBF (SimulatedBodyFluid) enquanto a imobilização do alendronato foi realizada a partir da imersão dos scaffolds em uma solução formada por SBF e medicamento durante 5 dias. As superfícies dos scaffolds foram avaliadas para cada etapa empregando microscopia eletrônica de varredura (MEV) e análise por difração de raios-X. Os scaffolds foram implantados na tíbia direita de 85 ratos machos da raça wistar com idade média de 12 semanas. A microtomografia computadorizada (µCT) e análise histológica foram realizadas para avaliar o reparo ósseo no defeito. As micrografias das superfícies obtidas mostraram mudanças no aspecto da superfície e composição química de acordo com o tratamento. O tratamento biomimético promoveu o crescimento da apatita sobre a superfície enquanto a imobilização com alendronato suprimiu sua formação. As imagens obtidas na microtomografia mostraram elevado valor de densidade óssea para o último grupo. No entanto, análises histológicas mostraram a formação de cápsula fibrosa em torno dos scaffolds a qual foi minimizada usando ultrassom pulsado de baixa intensidade. No entanto, mais estudos precisam ser realizados para avaliar a influência da geometria dos scaffolds na incorporação de medicamentos. / The objective of this in vivo study was to verify the bone response of coated Ti6Al4V porous scaffolds processed by Direct Metal Laser Sintering (DMLS) technique associated to low intensity pulsed ultrasound therapy. Scaffolds were processed by using Direct Metal Laser Sintering technique (DMLS) and heat treated at 1000 °C for 24 hours. Three types of surface treatments were evaluated: alkaline, biomimetic and sodium alendronate immobilization. For alkaline treatment, samples were immersed in a NaOH (5M) solution at 60ºC for 24 hours. Biomimetic treatment consisted in the immersion of the scaffolds into Simulated Body Fluid solution while for sodium alendronato immobilization the scaffolds were immersed in the solution formed by SBF plus drug during 5 days. The scaffolds surfaces were evaluated after each step employing SEM (Scanning Electron Microscopy)and X-rays diffraction analysis(XRD). Scaffolds were implanted into right tibia of 85 male Wistar rats with average age of 12 weeks. X-rays micro-computed tomography (µCT) and histological analysis were carried out to evaluate the bone repair on the defect. Micrographs analysis showed that the aspect of the surfaces and chemical composition changed according treatment. Biomimetic treatment promoted the growth of the apatite on the surface; in contrast the immobilization of alendronate suppressed apatite formation. Micro CT images showed higher value of bone density for the last group. However, histological analysis showed the formation of encapsulation fibrous around the scaffolds. This formation was minimized by using low intensity pulsed ultrasound technique, however, more studies can be carried out to evaluate the influence of scaffolds geometry in the drug incorporation.

Esta investigação tem a finalidade estudar experimentalmente os efeitos do ultra-som pulsado de baixa intensidade sobre a espermatogênese de ratos pré-púberes e adultos. Foram utilizados 40 ratos machos da raça Wistar, sendo 20 pré-púberes e 20 adultos, os quais tiveram os testículos estimulados por 15 minutos durante 10 dias consecutivos. Cada grupo experimental constou de 10 animais pré-púberes ou adultos, estimulados com o ultra-som pulsado de baixa intensidade ou não estimulados. Administrou-se Colchicina, 6 horas antes do sacrifício dos animais com a finalidade de bloquear a divisão das células em metáfase para facilitar a avaliação do ciclo espermatogenético. Mediante morfometria estimou-se as áreas dos túbulos seminíferos e fez-se a avaliação dos estadios do ciclo espermatogenético quando foi constatado um aumento significativo das áreas dos túbulos seminíferos dos animais estimulados. O ciclo espermatogenético de ratos pré-púberes e adultos foi avaliado mediante contagens de associações celulares do ciclo nos estadios VII e VIII e XIV, correspondentes ao fim e início de cada ciclo. Houve aumento temporal do ciclo espermatogenético por apresentar maior número de associações com características dos estadios VIII significando acentuada maturidade de espermatozóides nos ratos pré-púberes estimulados. Os testículos dos animais adultos estimulados apresentaram aumento de peso em relação aos dos controles, exibindo uma diferença significativa. Nossos resultados são compatíveis com a hipótese de que o ultra-som pulsado de baixa intensidade estimula o aumento do peso dos testículos dos ratos adultos e das áreas dos túbulos seminíferos, bem como acelerando o ciclo espermatogenético em ratos pré-púberes. / This is an experimental study of the effects of low intensity pulsed ultrasound on the spermatogenesis of prepubertal and adult male rats. Forty male Wistar rats - twenty prepubertal and twenty adults -, whose testicles were stimulated for fifteen minutes for ten consecutive days were studied. Each experimental group was composed of ten prepubertal or adult animals, stimulated with low intensity pulsed ultrasound or not. Six hours before killing, the rats were given Colchicine to block the division of metaphasic cells, in order to facilitate the assessment of the spermatogenetic cycle. The area of the seminiferous tubule was done estimated by morphometry and the stages of spermatogenetic cycle were assessed, showing a significant increase of the areas of the seminiferous tubules of the stimulated animals. The spermiogenesis of prepubertal and adult rats was assessed through counts of cell associations in the stages VII and VIII and XIV, corresponding to the end and beginning of each cycle. There was a temporal increase in the spermatogenetic cycle due to a higher number of the associations with stage VIII characteristics, which means accentuated sperm cell maturity of the stimulated prepubertal rats. The testicles of the stimulated animals were weight increase regarding the of the control animals, showing a significant difference. Our results are compatible with the hypothesis that the low intensity pulsed ultrasound stimulates the increase of the testicle weight, the rats adults, and the area of the seminiferous tubules as well as accelerating the spermatogenetic cycle in rats prepubertal.

京都大学 / 新制・課程博士 / 博士(人間健康科学) / 甲第23426号 / 人健博第93号 / 新制||人健||6(附属図書館) / 京都大学大学院医学研究科人間健康科学系専攻 / (主査)教授 山田 重人, 教授 林 悠, 教授 森本 尚樹 / 学位規則第4条第1項該当 / Doctor of Human Health Sciences / Kyoto University / DFAM

In recent years, the field of nanomedicine has provided promising alternatives to traditional ways of gene and drug delivery, such as nanobubbles instead of viral vectors. Manufacturing these nanomaterials is cost-effective and tends to be safer than previous forms of treatment for clinical use. In the realm of osteoporosis, a disease based around a higher rate of bone resorption to bone formation, leads to weak and brittle bones, leaving sufferers at risk for fractures, which are sudden and unexpected. These fractures are estimated to cost USD 22 Billion annually in the US alone. Reports show a significant effect on the quality of life after these fractures. Osteoclast-inhibiting oral medicines have been used to slow down bone resorption, but they have had severe side effects. This project aimed to study the impact of nanobubbles synthesized to target bone and filled with CTSK-siRNA to silence the Cathepsin K gene in an ovariectomized mice model. Cathepsin K is pivotal in osteoporosis as it is responsible for collagen degradation in bone resorption. Low-intensity pulsed ultrasound (LIPUS) for nanobubble destruction to facilitate targeted CTSK-siRNA release. LIPUS can also promote bone formation. We studied the effects of the treatment through histological analysis. Microarchitecture in the mice femur was highlighted through different types of staining such as Masson’s Trichrome, Hematoxylin & Eosin, and tartrate-resistant acid phosphatase staining. ImageJ was used for all measurements taken to interpret bone resorption in experimental groups. The major organs were studied to ensure the biocompatibility of nanobubble treatment. Our results show an increase in the average cortical thickness and trabecular spacing, but there was no significant increase in trabecular thickness in the group treated with CTSK-siRNA nanobubbles.

L'application d'ultrasons sur une tumeur, où des liposomes se sont accumulés, permet potentiellement de libérer le médicament mais aussi d'en favoriser l'absorption dans les cellules. La cavitation inertielle ultrasonore est le phénomène pressenti pour la libération sous ultrasons de médicament encapsulé dans de petits liposomes solides. Elle est très dépendante des conditions expérimentales et peut-être intense et imprévisible. L'objectif principal du travail réalisé dans le cadre de cette thèse est de contrôler et quantifier la cavitation inertielle, pour induire le largage de médicaments encapsulés dans des liposomes. Dans cette optique, une dose de cavitation inertielle (DC), basée sur le filtrage du bruit large bande émis lors de ce régime de cavitation, est mise au point in vitro pour suivre le largage de médicament encapsulé. Sous divers régimes d'ultrasons pulsés, la DC a été validée en dosant chimiquement les radicaux hydroxyles générés lors de l'implosion des bulles. Les tests menés sur diverses formulations de liposomes contenant de la doxorubicine (dox) ont montrés une haute corrélation entre le taux de largage de dox et la DC permettant de conclure que la cavitation inertielle est impliquée dans ce largage. Le rôle de la température sur la production de radicaux hydroxyles et la libération de dox a également été exploré. Les expériences réalisées ont permis de sélectionner les formulations les plus sensibles aux ultrasons pour les tester sur des rats implantés avec des tumeurs prostatiques. Après plusieurs expériences in vivo menées avec différents dispositifs ultrasonores et formulations de liposomes, le bénéfice du traitement combiné a pu être démontré. / The sonication of a tumor, where liposomes have been accumulated, allows potentially to release encapsulated drug and to promote its absorption in cells. Ultrasonic inertial cavitation is supposed to be implicated in the release of drug encapsulated in small solid liposomes under ultrasonic exposure. Inertial cavitation is strongly dependent on experimental conditions and can be very intense and unpredictable. The main objective of this thesis was to control and quantify inertial cavitation in order to induce drug release from liposomes. In this purpose, an inertial cavitation dose (CD), based on broadband noise emission associated with inertial cavitation, was defined to monitor in vitro encapsulated drug release. The CD was chemically validated with the dosing of hydroxyl radicals generated by bubbles collapses under various pulsed ultrasound exposures. A high correlation between doxorubicin (dox) release rate from liposomes and CD was de monstrated for all liposomes formulations tested and under different pulsed ultrasound exposures. The role of temperature on hydroxyl radical production and dox release was also investigated. The performed experiments allowed selecting the liposomes formulations that are the most sensible to ultrasound in order to test them on rats implanted with prostatic tumors. After several campaigns of in vivo experiments performed with various ultrasonic setups and liposomes formulations, the benefit of the combined treatment was demonstrated.