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Characterization of Breast Cancer with Manganese-enhanced Magnetic Resonance ImagingNofiele Tchouala, Joris Igor 19 March 2014 (has links)
Highly metastatic cancer cells are more likely to escape and form metastases,
and only minimal improvements in treatment can be achieved. Despite metas-
tases being the primary cause of cancer-related mortality, they often proceed
unnoticed. Current imaging modalities rely solely on the morphological fea-
tures of the tumor for characterization, rather than cellular differences. Our
goal is to develop an MR cellular imaging capability for characterizing the po-
tential of breast cancer cells to metastasize and enable early cancer detection
using manganese. Experiments on breast cell lines demonstrated that aggres-
sive cancer cells significantly enhanced on T1 -weighted MR images as a result
of a higher uptake and retention of manganese. These results suggest that dif-
ferences in uptake of manganese can help the detection and characterization
of breast cancers. The proposed technique can also be useful for other cancers,
and could bring a critically needed dimension to cancer imaging.
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Characterization of Breast Cancer with Manganese-enhanced Magnetic Resonance ImagingNofiele Tchouala, Joris Igor 19 March 2014 (has links)
Highly metastatic cancer cells are more likely to escape and form metastases,
and only minimal improvements in treatment can be achieved. Despite metas-
tases being the primary cause of cancer-related mortality, they often proceed
unnoticed. Current imaging modalities rely solely on the morphological fea-
tures of the tumor for characterization, rather than cellular differences. Our
goal is to develop an MR cellular imaging capability for characterizing the po-
tential of breast cancer cells to metastasize and enable early cancer detection
using manganese. Experiments on breast cell lines demonstrated that aggres-
sive cancer cells significantly enhanced on T1 -weighted MR images as a result
of a higher uptake and retention of manganese. These results suggest that dif-
ferences in uptake of manganese can help the detection and characterization
of breast cancers. The proposed technique can also be useful for other cancers,
and could bring a critically needed dimension to cancer imaging.
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Magnetic resonance image analysis techniques for quantification of hippocampal integrity in temporal lobe epilepsyWebb, Jocasta Anne January 2000 (has links)
No description available.
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Effect of Material Properties and Hemodynamics on the Healing of Vascular Grafts in baboonsCostello, James Robert 12 April 2004 (has links)
Each year, more than one million prosthetic vascular grafts are implanted. Well-over 50 % of these artificial vessels are of the small caliber variety with an inner diameter less than or equal to 10 mm. The challenge rests in implanting these synthetic substitutes into a hemodynamic environment with a high downstream resistance and low rates of flow.
Over the course of four interrelated studies, we investigated the healing properties of small caliber prosthetic vascular grafts. All of these studies were conducted using baboons. First, we documented the difference in healing response between three different types of vascular grafts: (1) autologous artery (2) allogeneic vessel (3) prosthetic ePTFE. This comparison furnished an important model of graft healing. Proliferating endothelial cells were localized to the top 10 % of the neointima, while the proliferating smooth muscle cells were identified within the lower 10 % of the neointima.
Secondly, we examined the effects of changing a prosthetic grafts material properties and how that change impacts healing of the grafts surface. These ultrastructural changes were introduced by radially stretching a porous 60 mm ePTFE vascular graft. Radially stretching the graft material decreased the void fraction, reduced the potential for transmural ingrowth, and changed the healing characteristics of the implanted vessels.
Thirdly, we investigated the effect of a changing hemodynamic environment upon the healing of a vascular graft with uniform material properties. The changing hemodynamics were generated with a stenotic model. Under sub-acute conditions, an inverse relationship failed to exist between intimal thickening and wall shear stress.
Lastly, the details of this hemodynamic environment were documented with computational fluid dynamics (CFD). The computational grids were constructed using three sets of geometric information: (1) incorporating the ideal material dimensions of the implanted vessel (2) utilizing contour information from pressure-perfused histologic cross-sections (3) applying geometric information form detailed MRI imaging. MRI imaging information provided the best description of the vessels hemodynamic environment. With this computational information, correlations were made between the intimal thickening and hemodynamic parameters.
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Visual, magnetic resonance, and genetic studies of outcome in multiple sclerosisWeatherby, Stuart J. M. January 2001 (has links)
No description available.
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ENGINEERING NANOMATERIALS FOR IMAGING AND ANTIBIOFILM APPLICATIONSWickramasinghe, Sameera M. 02 June 2020 (has links)
No description available.
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Análise por imagem do sistema nervoso central e do fenótipo de indivíduos brasileiros com síndrome de Optiz G/BBB / Image analysis of the central nervous system and the phenotype of Brazilian individuals with Opitz G/BBB syndromeSiemann, Maria Eugênia 26 June 2014 (has links)
O presente estudo é focalizado na avaliação dos achados do sistema nervoso central através de imagens obtidas através de ressonância nuclear magnética (RNM) em pacientes com a Síndrome de Opitz G/BBB. A síndrome de Opitz G/BBB (OMIM; 145410; 300000) é uma síndrome de anomalias congênitas múltiplas que comprometem a linha média, clinica e geneticamente heterogênea, com uma forma ligada ao cromossomo X mapeada em Xp22.3 e uma outra forma supostamente autossômica dominante mapeada em 22q11 cujo gene nunca foi identificado; no entanto, ambas são reconhecidas como uma condição única. Esta síndrome de anomalias da linha média se caracteriza principalmente por hipertelorismo, bico de viúva, ponte nasal larga, hipospádia, fissura de lábio/palato, e anomalias laringo-traqueo-esofágicas. Neste estudo avaliamos 19 pacientes do sexo masculino, brasileiros, sem etnia específica, com idades variando entre 5 e 38 anos, diagnosticados previamente como portadores de síndrome de Opitz G/BBB, selecionados dos arquivos da Seção de Genética Clinica, Divisão de Sindromologia, HRAC-USP Bauru. Destes pacientes, 6 tinham avaliação prévia por estudos de genética molecular gentilmente realizados pelas Dras. Chiara Migliore (Institute for Maternal and Child Health - IRCCS \"Burlo Garofolo\", Trieste, Italy) e Germana Meroni (CBM - Cluster in Biomedicine, AREA Science Park, Trieste, Italy). Os estudos por imagem através de RNM foram realizados em todos os pacientes. Atenção especial foi dedicada a 3 pacientes que mostravam fenótipos clínicos distintos dos demais dentro do espectro da síndrome de Opitz G/BBB: dois pacientes apresentavam ptose, pescoço alado, e anomalias da cintura escapular, enquanto que o terceiro apresentava retardo mental grave e microcefalia associado a graves alterações encefálicas na avaliação por imagem, tais como atrofia cortical generalizada e grande anomalia de Dandy-Walker. Os principais achados por imagem da amostra total são representados por cisterna magna ampla (15 indivíduos = 78,95%), dilatação do 4º ventrículo (14 = 73,68%), hipoplasia do vermis cerebelar (8 = 42,10%), hemisférios cerebelares anômalos e cavum septum vergae (3 = 15,79% cada condição); atrofia de córtex cerebral, alargamento do III ventrículo, aumento da cisterna pré-pontina, hipoplasia de corpo caloso e persistência de septo pelúcido contam, cada um, com dois pacientes acometidos (10,53%). Aparentemente não havia correlação entre o fenótipo clínico e os achados por imagem, existindo grande variabilidade de paciente para paciente, que se estendiam desde discretas alterações da linha média até grave malformação de Dandy-Walker. As alterações comportamentais e cognitivas usualmente descritas na literatura como achados principais em pacientes com hipoplasia do vermis cerebelar e/ou hipoplasia cerebelar não foram reconhecidas como achados marcantes nos pacientes do presente trabalho. A alta frequência de anomalias cerebelares em pacientes com a síndrome de Opitz G/BBB nos leva a recomendação para a reformulação do aconselhamento genético, abordagem e manejo destes pacientes. / The present survey focused on the evaluation of the central nervous system images findings in patients with the Opitz G/BBB syndrome obtained through magnetic nuclear resonance imaging (MRI). The Opitz G/BBB syndrome (OMIM; 145410; 300000) is a midline congenital malformation syndrome, clinical and genetically heterogeneous with an X-linked form mapped on Xp22.3 and a not well defined autosomal dominant form purportedly on 22q11, however they are recognized as one entity. This multiple congenital midline malformation syndrome is mainly characterized by hypertelorism, widows peak, broad nasal bridge, hypospadias, cleft lip/palate, and laryngo-tracheo-esophageal abnormalities. In the present study we have evaluated nineteen male patients of Brazilian extraction, with no preferential ethnic background, with age span ranging from 5 to 38 years old and previously diagnosed with the OS were selected from the files of the Section of Clinical Genetics, Division of Syndromology, HRAC-USP Bauru. From these patients, six had previous evaluation through molecular analysis graciously performed by Chiara Migliore (Institute for Maternal and Child Health - IRCCS \"Burlo Garofolo\", Trieste, Italy) and Germana Meroni (CBM - Cluster in Biomedicine, AREA Science Park, Trieste, Italy). Imaging studies through MRI were performed in all patients. Special attention was given to 3 out the 19 patients who showed unique phenotypes within the OS spectrum: 2 of them presented ptosis, pterigium colli, and abnormal scapular girdle as deviant signs and they presented mild/moderate cerebellar anomalies, and the 3rd presented severe mental retardation and microcephaly associated to generalized severe imaging findings mainly represented by generalized cortical atrophy and huge Dandy-Walker anomaly. Main MRI findings of the whole sample included wide cisterna magna (15 = 78,95%), enlarged 4th ventricle (14 = 73,68%), cerebellar vermis hypoplasia (8 = 42,10%); abnormal cerebellar hemispheres and cavum septum vergae (3 = 15,79% each one); cerebral cortical atrophy, enlarged III ventricle, enlarged prepontine cisterna, calosal hypoplasia and cavum septum pellucidum counts, each one, two patients (10,53%). Apparently there is no correlation between the clinical phenotype and the imaging findings, and there is a wide variability from patients to patients, ranging from mild midline anomalies to severe Dandy Walker anomaly. Behavioral and severe cognitive deficits usually reported in the pertinent literature as main findings associated to cerebellar vermis hypoplasia and/or cerebellar hypoplasia were not recognized as a remarkable finding in the present series. The high frequency of cerebellar anomalies in the OS patients led us to recommend a reformulation in the genetic counseling approach to these patients.
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Análise por imagem do sistema nervoso central e do fenótipo de indivíduos brasileiros com síndrome de Optiz G/BBB / Image analysis of the central nervous system and the phenotype of Brazilian individuals with Opitz G/BBB syndromeMaria Eugênia Siemann 26 June 2014 (has links)
O presente estudo é focalizado na avaliação dos achados do sistema nervoso central através de imagens obtidas através de ressonância nuclear magnética (RNM) em pacientes com a Síndrome de Opitz G/BBB. A síndrome de Opitz G/BBB (OMIM; 145410; 300000) é uma síndrome de anomalias congênitas múltiplas que comprometem a linha média, clinica e geneticamente heterogênea, com uma forma ligada ao cromossomo X mapeada em Xp22.3 e uma outra forma supostamente autossômica dominante mapeada em 22q11 cujo gene nunca foi identificado; no entanto, ambas são reconhecidas como uma condição única. Esta síndrome de anomalias da linha média se caracteriza principalmente por hipertelorismo, bico de viúva, ponte nasal larga, hipospádia, fissura de lábio/palato, e anomalias laringo-traqueo-esofágicas. Neste estudo avaliamos 19 pacientes do sexo masculino, brasileiros, sem etnia específica, com idades variando entre 5 e 38 anos, diagnosticados previamente como portadores de síndrome de Opitz G/BBB, selecionados dos arquivos da Seção de Genética Clinica, Divisão de Sindromologia, HRAC-USP Bauru. Destes pacientes, 6 tinham avaliação prévia por estudos de genética molecular gentilmente realizados pelas Dras. Chiara Migliore (Institute for Maternal and Child Health - IRCCS \"Burlo Garofolo\", Trieste, Italy) e Germana Meroni (CBM - Cluster in Biomedicine, AREA Science Park, Trieste, Italy). Os estudos por imagem através de RNM foram realizados em todos os pacientes. Atenção especial foi dedicada a 3 pacientes que mostravam fenótipos clínicos distintos dos demais dentro do espectro da síndrome de Opitz G/BBB: dois pacientes apresentavam ptose, pescoço alado, e anomalias da cintura escapular, enquanto que o terceiro apresentava retardo mental grave e microcefalia associado a graves alterações encefálicas na avaliação por imagem, tais como atrofia cortical generalizada e grande anomalia de Dandy-Walker. Os principais achados por imagem da amostra total são representados por cisterna magna ampla (15 indivíduos = 78,95%), dilatação do 4º ventrículo (14 = 73,68%), hipoplasia do vermis cerebelar (8 = 42,10%), hemisférios cerebelares anômalos e cavum septum vergae (3 = 15,79% cada condição); atrofia de córtex cerebral, alargamento do III ventrículo, aumento da cisterna pré-pontina, hipoplasia de corpo caloso e persistência de septo pelúcido contam, cada um, com dois pacientes acometidos (10,53%). Aparentemente não havia correlação entre o fenótipo clínico e os achados por imagem, existindo grande variabilidade de paciente para paciente, que se estendiam desde discretas alterações da linha média até grave malformação de Dandy-Walker. As alterações comportamentais e cognitivas usualmente descritas na literatura como achados principais em pacientes com hipoplasia do vermis cerebelar e/ou hipoplasia cerebelar não foram reconhecidas como achados marcantes nos pacientes do presente trabalho. A alta frequência de anomalias cerebelares em pacientes com a síndrome de Opitz G/BBB nos leva a recomendação para a reformulação do aconselhamento genético, abordagem e manejo destes pacientes. / The present survey focused on the evaluation of the central nervous system images findings in patients with the Opitz G/BBB syndrome obtained through magnetic nuclear resonance imaging (MRI). The Opitz G/BBB syndrome (OMIM; 145410; 300000) is a midline congenital malformation syndrome, clinical and genetically heterogeneous with an X-linked form mapped on Xp22.3 and a not well defined autosomal dominant form purportedly on 22q11, however they are recognized as one entity. This multiple congenital midline malformation syndrome is mainly characterized by hypertelorism, widows peak, broad nasal bridge, hypospadias, cleft lip/palate, and laryngo-tracheo-esophageal abnormalities. In the present study we have evaluated nineteen male patients of Brazilian extraction, with no preferential ethnic background, with age span ranging from 5 to 38 years old and previously diagnosed with the OS were selected from the files of the Section of Clinical Genetics, Division of Syndromology, HRAC-USP Bauru. From these patients, six had previous evaluation through molecular analysis graciously performed by Chiara Migliore (Institute for Maternal and Child Health - IRCCS \"Burlo Garofolo\", Trieste, Italy) and Germana Meroni (CBM - Cluster in Biomedicine, AREA Science Park, Trieste, Italy). Imaging studies through MRI were performed in all patients. Special attention was given to 3 out the 19 patients who showed unique phenotypes within the OS spectrum: 2 of them presented ptosis, pterigium colli, and abnormal scapular girdle as deviant signs and they presented mild/moderate cerebellar anomalies, and the 3rd presented severe mental retardation and microcephaly associated to generalized severe imaging findings mainly represented by generalized cortical atrophy and huge Dandy-Walker anomaly. Main MRI findings of the whole sample included wide cisterna magna (15 = 78,95%), enlarged 4th ventricle (14 = 73,68%), cerebellar vermis hypoplasia (8 = 42,10%); abnormal cerebellar hemispheres and cavum septum vergae (3 = 15,79% each one); cerebral cortical atrophy, enlarged III ventricle, enlarged prepontine cisterna, calosal hypoplasia and cavum septum pellucidum counts, each one, two patients (10,53%). Apparently there is no correlation between the clinical phenotype and the imaging findings, and there is a wide variability from patients to patients, ranging from mild midline anomalies to severe Dandy Walker anomaly. Behavioral and severe cognitive deficits usually reported in the pertinent literature as main findings associated to cerebellar vermis hypoplasia and/or cerebellar hypoplasia were not recognized as a remarkable finding in the present series. The high frequency of cerebellar anomalies in the OS patients led us to recommend a reformulation in the genetic counseling approach to these patients.
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Σύνθεση και χαρακτηρισμός φερριτικών νανοκολλοειδών με προσθήκη προσμίξεων ψευδαργύρου και μαγγανίου / Synthesis and characterization of ferrite nanocolloids doped with zinc and manganeseΠαπαϊωάννου, Νικόλαος 10 December 2013 (has links)
Τα δομικά χαρακτηριστικά των μαγνητικών κολλοειδών με βάση το οξείδιο του σιδήρου είναι ιδιαίτερα σημαντικά κατά την χρήση τους σε βιοϊατρικές εφαρμογές όπως η απεικόνιση σε μαγνητικό τομογράφο (MRI), η μεταφορά φαρμάκων, η μαγνητική υπερθερμία και στόχευση. Ιδιαίτερα για την μαγνητική στόχευση, η αύξηση της μαγνήτισης κορεσμού των κολλοειδών είναι ιδιαίτερης σημασίας. Συνεπώς, η μελέτη της σχέσης δομής-ιδιοτήτων είναι απαραίτητη για την περαιτέρω βελτίωση της απόδοσης των εν λόγω συστημάτων στις προαναφερθείσες εφαρμογές. Με στόχο τη βελτίωση της μαγνήτισης κορεσμού αυτών των υλικών έχει μελετηθεί στο παρελθόν μια στρατηγική αντικατάστασης ενός ποσοστού ιόντων σιδήρου στη δομή του νανοκρυστάλλου με άλλα μεταλλικά ιόντα. Οι μελέτες αυτές έχουν δείξει πως αναλόγως της συνθετικής πορείας άλλοτε επιτυγχάνεται το επιθυμητό αποτέλεσμα και άλλοτε όχι. Σε αυτά τα πλαίσια, σκοπός της παρούσας εργασίας ήταν η εφαρμογή αυτής της στρατηγικής σε μία συνθετική πορεία ανάπτυξης μαγνητικών νανοκολλοειδών στην οποία δεν έχει εκτιμηθεί μέχρι τώρα η επιτυχία της. Το ενδιαφέρον έγκειται στο γεγονός ότι η συγκεκριμένη συνθετική πορεία οδηγεί σε νανοκρυσταλλίτες οξειδίου του σιδήρου με αυξημένες μαγνητικές ιδιότητες σε σχέση με τη βιβλιογραφία, οι οποίες θα μπορούσαν (πιθανώς) να βελτιωθούν ακόμα περισσότερο με μερική ιοντική αντικατάσταση.
Τα νανοκολλοειδή παρασκευάστηκαν με την μέθοδο της υδρολυτικής αλκαλικής καταβύθισης από μία πρόδρομη ένωση σιδήρου (FeCl2 ή FeSO4), με προσμίξεις διαφόρων αναλογιών με Zn(Cl2/SO4) ή Mn(Cl2/SO4). Η χημική τροποποίηση της επιφάνειας των μαγνητικών νανοκολλοειδών έγινε με στοχευμένη προσθήκη του φυσικού βιοπολυμερούς του αλγινικού νατρίου κατά τη διαδικασία κρυστάλλωσης του ανόργανου μαγνητικού πυρήνα.
Η μελέτη των φυσικοχημικών χαρακτηριστικών και της δομής των νανοφορέων πραγματοποιήθηκε με την χρήση των παρακάτω αναλυτικών τεχνικών: Ηλεκτρονική Μικροσκοπία Σάρωσης (SEM) σε συνδυασμό με Φασματομετρία Ενεργειακής Διασποράς Ακτινοβολίας-X (EDS), Περίθλαση Ακτινοβολίας-X (XRD), Θερμοσταθμική Ανάλυση (TGA), Δυναμική Σκέδαση Φωτός (DLS), Ηλεκτροκινητικές Μετρήσεις, Μαγνητομετρία Δονούμενου Δείγματος (VSM), Μαγνητοφόρηση και Μαγνητική Υπερθερμία Δείγματος. / Structural characteristics of magnetic ferrite nanocolloids are particularly important in biomedical applications such as magnetic resonance imaging (MRI), drug delivery, magnetic hyperthermia and targeting. Particularly about magnetic targeting, increasing saturation magnetization is crucial. Therefore, studying the structure-properties relation of colloids is necessary, in order to improve further the performance of these systems in the above applications. In order to enhance the saturation magnetization of those materials, substitution of a percentage of iron ions in the structure of the nanocrystal with other metal ions has been previously studied. Results have shown that the desired properties are obtained under certain circumstances, depending on the synthetic route. Within this frame, the goal of the present work is to test this strategy on a synthetic route which has not been so far evaluated. The interest lies in the fact that this synthetic route leads to iron oxide nanocrystallites with increased magnetic properties compared to the literature, which could (possibly) be further improved with partial ionic replacement.
Nanocolloids were synthesized by hydrolytic alkaline precipitation from a single iron molecular precursor (FeCl2 or FeSO4), doped at different ratios with Zn(Cl2/SO4) or Mn(Cl2/SO4). The surface modification of the magnetic nanocolloids was performed by in-situ grafting of the natural biopolymer of sodium alginate, during the crystallization process of the inorganic magnetic core.
The evaluation of the structural, magnetic and physicochemical characteristics of the nanocarriers was performed with the use of the following analytical techniques: Scanning Electron Microscopy (SEM) in conjunction with Energy-Dispersive X-Ray Spectrometry (EDS), X-Ray Diffraction (XRD), Thermal Gravimetric Analysis (TGA), Dynamic Light Scattering (DLS), Electrokinetic Measurements, Vibrating Sample Magnetometer (VSM), Magnetophoresis and Magnetic Hyperthermia of the Sample.
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Path reconstruction in diffusion tensor magnetic resonance imagingSong, Xin 13 July 2011 (has links) (PDF)
The complicated underwater environment and the poor underwater vision make super-mini underwater cable robot hardly to be controlled. Traditionally, the manual control method by operators is adopted by this kind of robots. Unfortunately, the robots can hardly work normally in these practical circumstances. Therefore, to overcome these shortcomings and improve the abilities of these underwater cable robots, this paper proposes several improvements, including the system design, the motion controller design, three dimensional obstacle recognition and three dimensional path reconstruction technologies etc. The details are displayed as follow: (1) Super-mini underwater robot system design: several improvement schemes and important design ideas are investigated for the super-mini underwater robot.(2) Super-mini robot motion controller design: The motion controller design of underwater robot in complicated circumstance is investigated. A new adaptive neural network sliding mode controller with balanced parameter controller (ANNSMB) is proposed. Based on the theory of adaptive fuzzy sliding mode controller (AFSMC), an improved algorithm is also proposed and applied to the underwater robot. (3)Research of three dimensional underwater environment reconstructions: The algorithms and the experiments of underwater environment reconstructions are investigated. DT-MRI image processing algorithm and the theory of three dimensional obstacle reconstructions are adopted and improved for the application of the underwater robot. (4) The super-mini underwater robot path planning algorithms are investigated.
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