Diffusion imaging with balanced steady state free precession

Balanced steady state free precession (bSSFP) offers high signal efficiency and relative motion insensitivity. In this study, diffusion weighted bSSFP (DW-bSSFP) was introduced by modifying standard bSSFP sequence with two pairs of balanced bipolar diffusion gradients. The diffusion effect was analyzed and described in closed forms. It was found to be coupled to the transverse and longitudinal relaxation, flip angle and spin phase advance per TR. Such coupling was demonstrated in phantom experiment at 7T. Preliminary DW-bSSFP imaging experiment was performed in rat brain in vivo for diffusion tensor imaging, yielding parametric maps qualitatively similar to those obtained with an 8-shot DW-EPI protocol. The proposed DW-bSSFP approach can provide a new means of diffusion imaging with high resolution, relative motion insensitivity and short diffusion time. Such approach may lead to improved and new diffusion characterization of neural tissues, abdominal organs, myocardium and musculoskeletal tissues. © 2012 IEEE.published_or_final_versio

Advanced MR diffusion characterization of neural tissue using directional diffusion kurtosis analysis.

Conference Theme: Personalized Healthcare Through TechnologyMR Diffusion kurtosis imaging (DKI) was proposed recently to study the deviation of water diffusion from Gaussian distribution. Mean kurtosis (MK), directionally averaged kurtosis, has been shown to be useful in assessing pathophysilogical changes. However, MK is not sensitive to kurtosis change occurring along a specific direction. Therefore, orthogonal transformation of the 4th order kurtosis tensor was introduced in the current study to compute kurtoses along the 3 eigenvector directions of the 2nd order diffusion tensor. Such axial (K( parallel)) and radial (K perpendicular) kurtoses measured the kurtoses along the directions parallel and perpendicular, respectively, to the principal diffusion direction. DKI experiments were performed in normal adult and formalin-fixed rat brain, and developmental brains. The results showed that directional kurtosis analysis revealed different information for tissue characterization.published_or_final_versio

Factors influencing adolescent girls' decision in initiation for human papillomavirus vaccination: A cross-sectional study in Hong Kong

Background: Cervical cancer is one of the common cancers among women worldwide. Despite HPV vaccination being one of the effective preventive measures, it is not included in government vaccination programme in Hong Kong. This study aimed to assess the knowledge of and attitude towards cervical cancer prevention among Chinese adolescent girls in Hong Kong, and to identify factors influencing the initiation of HPV vaccination. Methods: This was a cross-sectional study conducted in Hong Kong during the period of October 2010 to November 2010. A self-administered questionnaire was used, with 1,416 girls from 8 secondary schools completing the questionnaire. Knowledge scores were composited and initiation of HPV vaccination was staged based on stage of change. Analyses were conducted to identify the association of initiation of HPV vaccination with participant's personal and family factors as well as their knowledge and attitude towards cervical cancer prevention. Results: The uptake rate of HPV vaccination was low (7%) with 58% respondents in pre-contemplation and contemplation stage. The survey identified a significant gap in knowledge on cervical cancer prevention. The main channels of information were from media and very few from schools or parents. However, 70% expressed their wishes to have more information on cancer prevention, and 78% stated that they were willing to change their lifestyles if they knew the ways of prevention. Multivariate analysis identified three independent significant factors for initiation of vaccination (action and intention): perceived cancer as terrifying disease, school should provide more information on cancer prevention, and comments from relatives and friends having received the vaccine. The cost of vaccination and socio-economic background were not found to be significant. Conclusions: Public education on cervical cancer needs to be well penetrated into the community for more sharing among friends and relatives. School as setting to provide source of information would facilitate uptake rate of HPV vaccine as students have expressed their wishes that school should provide more information on prevention of cancer. School and community education on cancer prevention would help adolescents to have better understanding of the seriousness of cancer. © 2014 Lee et al.; licensee BioMed Central Ltd.link_to_subscribed_fulltex

Functional MRI of postnatal visual development in normal rat superior colliculi

Theme: Engineering the Future of BiomedicineThis study employed blood oxygenation level-dependent functional MRI (BOLD-fMRI) to evaluate the visual responses in the superior colliculus of the developing rat brain from the time of eyelid opening to adulthood. Upon flash illumination to the contralateral eye, the regional BOLD response underwent a systematic increase in amplitude with age especially after the third postnatal week. However, no significant difference in BOLD signal increase was found between postnatal days 14 and 21. Our results constitute the first fMRI report in demonstrating the critical period of visual functions in the rat brain during maturation. This can be potentially useful in establishing the links between changes in relation to visual sensory development. ©2009 IEEE.published_or_final_versionThe 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC 2009), Minneapolis, MN., 3-6 September 2009. In Proceedings of the 31st EMBC, 2009, p. 4436-443

Noninvasive fMRI investigation of interaural level difference processing the rat auditory subcortex

published_or_final_versio

In vivo diffusion tensor imaging of chronic spinal cord compression in rat model

Conference Theme: Engineering the Future of BiomedicineChronic spinal cord compression induced cervical myelopathy is a comon cause of spinal cord dysfunction. The exact mechanisms of underlying progressive cell death remain to be elucidated. In this study, in vivo diffusion tensor imaging (DTI) has been applied to investigate the microstructural changes of white matter (WM) in this neurodegenerative disease. Compared with conventional MRI techniques, DTI is believed to be more specific to pathological changes. Radial diffusivity (λ⊥) is higher in the ipilesional region, suggesting demyelination or axonal degradation may occur after prolonged compression. Near the epicenter of lesion, axial diffusivity (λ∥) is lower. Also, caudal-rostral asymmetry has been observed in λ∥. Feasibility of using DTI to detect microstructural changes in chronic disease has been demonstrated. ©2009 IEEE.published_or_final_versionThe 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC 2009), Minneapolis, MN., 3-6 September 2009. In Proceedings of the 31st EMBC, 2009, p. 2715-271

Review of Nanomedicine

The field of nanomedicine holds vast potential for the improvement of health care around the world and the coming nanomedical revolution will surely bring innovative solutions to many of the difficulties we currently encounter in the realm of patient treatment. Nanomedicine is a relatively new field for scientific inquiry. It is defined as the use of nanoscale devices or materials to diagnose and cure diseases by actively interacting at the molecular level within a cellular system. In the context of nanotechnology, the “molecular level” refers to structures less than 100 nanometers in diameter. Given the breadth of this definition of nanomedicine, it can be narrowed and made more applicable when only those devices or medicines designed to function on the nanoscale are considere

Duplications of the critical Rubinstein-Taybi deletion region on chromosome 16p13.3 cause a novel recognisable syndrome

Background The introduction of molecular karyotyping technologies facilitated the identification of specific genetic disorders associated with imbalances of certain genomic regions. A detailed phenotypic delineation of interstitial 16p13.3 duplications is hampered by the scarcity of such patients. Objectives To delineate the phenotypic spectrum associated with interstitial 16p13.3 duplications, and perform a genotype-phenotype analysis. Results The present report describes the genotypic and phenotypic delineation of nine submicroscopic interstitial 16p13.3 duplications. The critically duplicated region encompasses a single gene, CREBBP, which is mutated or deleted in Rubinstein-Taybi syndrome. In 10 out of the 12 hitherto described probands, the duplication arose de novo. Conclusions Interstitial 16p13.3 duplications have a recognizable phenotype, characterized by normal to moderately retarded mental development, normal growth, mild arthrogryposis, frequently small and proximally implanted thumbs and characteristic facial features. Occasionally, developmental defects of the heart, genitalia, palate or the eyes are observed. The frequent de novo occurrence of 16p13.3 duplications demonstrates the reduced reproductive fitness associated with this genotype. Inheritance of the duplication from a clinically normal parent in two cases indicates that the associated phenotype is incompletely penetrant

Early detection of neurodegeneration in brain ischemia by manganese-enhanced MRI

This study aims to employ in vivo manganese-enhanced MRI (MEMRI) to detect neurodegenerative changes in two models of brain ischemia, photothrombotic cortical injury (PCI) and transient middle cerebral artery occlusion (MCAO) in rodents. After systemic Mn 2+ injection to both ischemic models, a close pattern of Tl-weighted hyperintensity was observed throughout different brain regions in comparison to the distribution of GFAP, MnSOD and GS immunoreactivities, whereby conventional MRI could hardly detect such. In addition, the infarct volumes in the posterior parts of the brain had significantly reduced after Mn 2+ injection to the MCAO model. It is suggested that exogenous Mn 2+ injection may provide enhanced MEMRI detection of oxidative stress and gliosis early after brain ischemia. Manganese may also mediate infarctions at remote brain regions in transient focal cerebral ischemia before delayed secondary damage takes place. © 2008 IEEE.published_or_final_versionThe 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS) 2008, Vancouver, BC., 20-25 August 2008. in Proceedings of the 30th EMBS, 2008, p. 3884-388

Corpo-oralidades y territorio en la dramaturgia de Felipe Vergara, de la experiencia del conflicto al correlato artístico

Dissertação apresentada ao Programa de Pós- Graduação em Literatura Comparada da Universidade Federal da Integração Latino- Americana, como requisito parcial à obtenção do título de Mestre em Literatura Comparada. Orientador: Andrea Ciacchi (Pós-Doutor Universidade Estadual de Campinas , Doutor em Iberistica, Università di Bologn , a Mestro em Letras, Universidade Federal da Paraíba , Graduação em Antropologia, Università di Roma)Propongo una lectura de la poética teatral de Felipe Vergara desde el estudio de tres piezas: Kilele, una epopeya artesanal; Arimbato, el camino del árbol; y Coragyps Sapiens, partiendo por considerar el teatro como un encuentro vital entre los artistas y su público, que instala escrituras permeadas por el tiempo, la historia y el contexto de su surgimiento. En ese sentido planteo que la dramaturgia Vergara funciona como un correlato que revive el rastro de la experiencia de guerra de las comunidades del Pacífico colombiano, a la vez que toma una posición autónoma de resistencia artística, social y cultural, y que porta en su discurso las versiones silenciadas históricamente, las versiones subterráneas. Para el análisis abordo: la relación indisoluble de las comunidades con su territorio, manifiesta en las obras; las representaciones de cuerpo y su fragmentación tanto a nivel individual como colectivo; y su reconstrucción a través de los duelos que se encarnan en transmisiones rituales, corporales y orales, en actos de memoria viva. Presento así un recorrido por la propuesta artística de Felipe Vergara y un acercamiento a algunas propuestas teatrales las comunidades del Pacífico colombiano, en las que curiosamente, Vergara trabajó de la mano de Inge Kleutgens, Catalina Medina y otros colaboradores. Retomaremos tres obras de Vergara, así como tres de las creaciones colectivas de las comunidades con las que , rastreando en ellas los procesos y procedimientos para la reconstrucción de una porción de los relatos alternativos de la historia social de las vivencias del conflicto social y armado colombiano, traducidas en las relaciones entre los imaginarios y las representaciones simbólicas de las obras, que asocian las gamas de sentido del texto y de la puesta en escena, con el cauce efectivo que propicia su escritura.Proponho uma leitura da poesia teatral de Felipe Vergara a partir do estudo de três obras: Kilele, una epopeya artesanal; Arimbato, el camino del árbol; y Coragyps Sapiens, começando por considerar o teatro como um encontro vital entre os artistas e seu público, que instala escritos permeados pelo tempo, pela história e pelo contexto de seu surgimento. Nesse sentido, proponho que a dramaturgia de Vergara funcione como um correlato que revive o traço da experiência de guerra das comunidades do Pacífico colombiano, ao mesmo tempo em que assume uma posição autônoma de resistência artística, social e cultural, e que carrega em seu discurso as versões silenciadas historicamente, as versões subterrâneas. Pela análise a bordo: a relação indissolúvel das comunidades com seu território, manifestada nos trabalhos; representações corporais e sua fragmentação individual e coletiva; e sua reconstrução através dos duelos que se encarnam em transmissões rituais, corporais e orais, em atos de memória viva. Apresento um encontro com a proposta artística de Felipe Vergara, propostas teatrais das comunidades do Pacífico colombiano, nas quais curiosamente, Vergara trabalhou com Inge Kleutgens, Catalina Medina e outros colaboradores. Retornaremos a três obras de Vergara, bem como a três das criações coletivas das comunidades com as quais traçamos os processos e procedimentos para a reconstrução de uma parte dos relatos alternativos da história social das experiências do conflito social e armado colombiano , traduzido nas relações entre o imaginário e as representações simbólicas das obras, que associam as faixas de significado do texto e da encenação, ao canal efetivo que propicia sua escrit