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Sagittal Sections (sagittal + section)
Selected AbstractsReal time monitoring of BMP Smads transcriptional activity during mouse developmentGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 7 2008Rui M. Monteiro Sagittal section of a 5-day-old mouse kidney expressing a bone morphogenetic protein-response element:green fluorescent protein (BRE:gfp) transgene. GFP expression detected by immunofluorescence (green) reveals BMP Smad transcriptional activity in the glumeruli and adjacent collecting tubules. See the paper by Monteiro et al., in this issue. (Image provided by Monika Bialecka). [source] Reduced growth hormone receptor immunoreactivity in osteoclasts adjacent to the erupting molar in the incisor-absent (osteopetrotic) ratEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2003Anne L. Symons First molars fail to erupt in the incisor-absent (ia/ia) rat because of a defect in osteoclast function. Growth factors that regulate local bone metabolism include growth hormone (GH), insulin-like growth factor-I (IGF-I), epidermal growth factor (EGF) and interleukin-1 alpha (IL- 1,). Since osteoclast function may be affected by these factors, the aim of this study was to determine the distribution of GH receptor (GHr), IGF-I, EGF and IL-1,, in osteoclasts located occlusal to the erupting first molar, in the ,eruption pathway', in normal and ia/ia rats. Sagittal sections of the first molar and adjacent bone from 3- and 9-d-old animals were examined. Osteoclasts were identified using tartrate-resistant acid phosphatase (TRAP). The TRAP-positive osteoclast cell numbers were higher in ia/ia animals at 3 and 9 days-of-age. In the ia/ia group, fewer osteoclasts were GHr- and IGF-I-positive at 3 d of age, and at 9 d of age fewer osteoclasts were GHr-positive. In the ia/ia rat, defective osteoclast function failed to resorb bone to provide an eruption pathway for the lower first molar. The expression of GHr, and to some degree IGF-I, by these osteoclasts was reduced, which may be related to their ability to differentiate and function. [source] Navigator-gated three-dimensional MR angiography of the pulmonary arteries using steady-state free precession,JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2005Benjamin K. Hui AB Abstract Purpose To assess the quality of a navigator-gated, free breathing, steady-state free precession (SSFP) technique in comparison to a single breathhold for pulmonary artery imaging in normal volunteers. Materials and Methods Sagittal sections of the left pulmonary arteries of 10 volunteers were obtained with a three-dimensional SSFP sequence using both a single breathhold of 30 seconds and a navigator-gated version of the same sequence. The images were compared and rated by a blinded cardiovascular radiologist for image quality, sharpness, and artifact. Results On a scale ranging from ,2 to 2, in which positive numbers denote that the navigator method was favorable compared to the single breathhold method, image quality was rated 0.7 ± 1.4, sharpness 0.6 ± 1.5, and artifact 0.1 ± 1.4. Thus, there was no statistical difference between the two methods. Conclusion The navigator-gated SSFP sequence is able to acquire images equal in quality to the breathhold sequence. This may be of clinical importance for pulmonary imaging in patients who are unable to sustain a long breathhold. J. Magn. Reson. Imaging 2005;21:831,835. © 2005 Wiley-Liss, Inc. [source] Quantitative evaluation of automated skull-stripping methods applied to contemporary and legacy images: Effects of diagnosis, bias correction, and slice locationHUMAN BRAIN MAPPING, Issue 2 2006Christine Fennema-Notestine Abstract Performance of automated methods to isolate brain from nonbrain tissues in magnetic resonance (MR) structural images may be influenced by MR signal inhomogeneities, type of MR image set, regional anatomy, and age and diagnosis of subjects studied. The present study compared the performance of four methods: Brain Extraction Tool (BET; Smith [2002]: Hum Brain Mapp 17:143,155); 3dIntracranial (Ward [1999] Milwaukee: Biophysics Research Institute, Medical College of Wisconsin; in AFNI); a Hybrid Watershed algorithm (HWA, Segonne et al. [2004] Neuroimage 22:1060,1075; in FreeSurfer); and Brain Surface Extractor (BSE, Sandor and Leahy [1997] IEEE Trans Med Imag 16:41,54; Shattuck et al. [2001] Neuroimage 13:856,876) to manually stripped images. The methods were applied to uncorrected and bias-corrected datasets; Legacy and Contemporary T1 -weighted image sets; and four diagnostic groups (depressed, Alzheimer's, young and elderly control). To provide a criterion for outcome assessment, two experts manually stripped six sagittal sections for each dataset in locations where brain and nonbrain tissue are difficult to distinguish. Methods were compared on Jaccard similarity coefficients, Hausdorff distances, and an Expectation-Maximization algorithm. Methods tended to perform better on contemporary datasets; bias correction did not significantly improve method performance. Mesial sections were most difficult for all methods. Although AD image sets were most difficult to strip, HWA and BSE were more robust across diagnostic groups compared with 3dIntracranial and BET. With respect to specificity, BSE tended to perform best across all groups, whereas HWA was more sensitive than other methods. The results of this study may direct users towards a method appropriate to their T1 -weighted datasets and improve the efficiency of processing for large, multisite neuroimaging studies. Hum. Brain Mapping, 2005. © 2005 Wiley-Liss, Inc. [source] The Brain of the Dog in Section: a Comprehensive View for Veterinary StudentsANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005I. Salazar Transversal, horizontal and sagittal sections of the brain were stained by the ancient but efficient Mulligan method, a procedure that establishes a clear macroscopic difference between the white and grey substances. Different structures of each section were studied and most of the details were identified and named according to the NAV. All sections were projected onto the whole brain. By means of this easy and basic procedure the students increase their understanding of (1) the size and/or the form and/or the topography of several prominent structures of the brain, (2) the general distribution of the substancia alba and grisea, and they begin to understand the complexity of the brain. [source] Histological and Ultrastructural Analysis of White Matter Damage after Naturally-occurring Spinal Cord InjuryBRAIN PATHOLOGY, Issue 2 2006Peter M. Smith Detailed analysis of the structural changes that follow human clinical spinal cord injury is limited by difficulties in achieving adequate tissue fixation. This study bypasses this obstacle by examining the spinal cord from paraplegic domestic animals, enabling us to document the ultrastructural changes at different times following injury. In all but one case, injury resulted from a combination of contusion and compression. There was infarction and hemorrhage, followed by gray matter destruction and the rapid development of a variety of white matter changes including axon swelling and myelin degeneration. Axons greater than 5 µm in diameter were more susceptible to degenerative changes, whereas smaller axons, particularly those in the subpial region, were relatively well preserved. Demyelinated axons were seen within 2 weeks after injury and, at later time points, both Schwann cell and oligodendrocyte remyelination was common. More subtle white matter abnormalities were identified by examining sagittal sections, including focal accumulation of organelles in the axoplasm and partial and paranodal myelin abnormalities. These observations serve to validate observations from experimental models of spinal contusion but also highlight the complexity of naturally occurring (ie, clinical) spinal injury. They also raise the possibility that focal abnormalities such as paranodal demyelination may contribute to early axonal dysfunction and possibly to progressive tissue damage. [source] Pretarsal fat compartment in the lower eyelidCLINICAL ANATOMY, Issue 3 2001Kun Hwang Abstract It is generally accepted that there are three infraorbital fat regions in the lower eyelid; medial, central, and lateral compartments. However, removing only the fat in the lateral compartment does not remove the bulge just below the eyelashes, which is caused by another fat pad. The aim of this study was to describe the anatomy of the pretarsal fat compartment and to demonstrate its clinical implications in lower lid blepharoplasty. Ten cadavers (total 20 lower eyelids) were studied. A skin-muscle flap was reflected to expose the soft pretarsal structures. A small stab incision was made on the lateral portion of the sac containing fat on the tarsus. Methylene blue dye was injected into the sac. Specimens were fixed and sagittal sections in four different planes were prepared for histological analysis. The injected dye remained within the sac and demarcated it as a pear or cone shaped structure. This encapsulated fat compartment sits on the lateral half of the tarsal plate above the lateral compartment fat. Auxillary or submuscular fat is well known. This study, however, designates the pretarsal fat as "encapsulated" in a compartment instead of being unbound. We have named it the "pretarsal fat compartment." Histologically, orbital septal fibers separate "pretarsal fat" from lateral infraorbital fat. It is recommended that fat in the pretarsal fat compartment be removed during lower lid blepharoplasty in order to alleviate the bulge or knoll of the skin just below the lower eyelashes. Clin. Anat. 14:179,183, 2001. © 2001 Wiley-Liss, Inc. [source] | |||||||||||||