Diffusion of water molecules in biological tissues is conventionally quantified via diffusion tensor imaging (DTI) [1]. DTI enables a Gaussian approximation to the probability distribution governing the random displacement of water molecules. In some circumstances of great interest, however, the displacement probability distribution can deviate considerably from a Gaussian form. Diffusional kur...

Increased performance variability has been demonstrated in several groups and conditions, including aging and cognitive decline. Structural brain characteristics underlying this phenomenon have so far been elusive. However, there is reason to expect that disconnectivity in associative pathways, whether caused by immature or degraded white matter (WM) tracts, will increase performance variabilit...

OBJECTIVE The present study was aimed at evaluating the correlation between diffusion tensor imaging parameters and Loes score as well as whether those parameters could indicate early structural alterations. MATERIALS AND METHODS Diffusion tensor imaging measurements were obtained in 30 studies of 14 patients with X-linked adrenoleukodystrophy and were correlated with Loes scores. A control g...

Increasing evidence is emerging for sexual dimorphism in the trajectory of white matter development in children assessed using volumetric magnetic resonance imaging (MRI) and more recently diffusion MRI. Recent studies using diffusion MRI have examined cohorts with a wide age range (typically between 5 and 30 years) showing focal regions of differential diffusivity and fractional anisotropy (FA...

BACKGROUND AND PURPOSE The aim of this study was to characterize the diffusion properties of the entire human spinal cord in vivo. These data are essential for comparisons to pathologic conditions as well as for comparisons of different pulse sequence design parameters aimed to reduce scan time and more accurately determine diffusion coefficients. MATERIALS AND METHODS A total of 13 neurologi...

PURPOSE To evaluate the diagnostic contribution of diffusion-weighted magnetic resonance imaging (MRI) using apparent diffusion coefficient (ADC) values to the characterization of hepatic masses and differentiation of benign and malignant lesions. MATERIALS AND METHODS The study included 30 patients that underwent upper abdominal MRI examinations because of hepatic masses that were found to b...

Model simulations of nitric oxide (NO) transport considering molecular diffusion showed that the total bronchial NO production needed to reproduce a given exhaled value is deeply influenced by its axial distribution. Experimental data obtained by fibroscopy were available about proximal airway contribution (Silkoff PE, McClean PA, Caramori M, Slutsky AS. Zamel N. Respir Physiol 113: 33-38, 1998...

To identify developmental mechanisms that might have been involved in the evolution of axial sporophytes in early land plants, we examined the effects of auxin-regulatory compounds in the sporophytes of the hornwort Phaeoceros personii, the liverwort Pellia epiphylla, and the moss Polytrichum ohioense, members of the three divisions of extant bryophytes. The altered growth of isolated young spo...

Older male premutation carriers of the FMR1 gene are associated with the risk of developing a late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome. Although previous postmortem and in vivo magnetic resonance imaging studies have indicated white matter pathology, the regional selectivity of abnormalities, as well as their relationship with molecular variables of the...

Background. Exhaled nitric oxide (eNO) is a potential biomarker to distinguish systemic sclerosis (SSc) associated pulmonary arterial hypertension (PAH) and interstitial lung disease (ILD). We evaluated the discriminative validity, feasibility, methods of eNO measurement, and magnitude of differences across lung diseases, disease-subsets (SSc, systemic lupus erythematosus), and healthy-controls...