13 research outputs found
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New views of male pelvic anatomy: Role of computer-generated 3D images
There is considerable controversy concerning the role of cadaveric dissection in teaching gross anatomy and the potential of using 3D computer-generated images to substitute for actual laboratory dissections. There are currently few high-quality 3D virtual models of anatomy available to evaluate the utility of computer-generated images. Existing 3D models are frequently of structures that are easily examined in three dimensions by removal from the cadaver, i.e., the heart, skull, and brain. We have focused on developing a 3D model of the pelvis, a region that is conceptually difficult and relatively inaccessible for student dissection. We feel students will benefit tremendously from 3D views of the pelvic anatomy. We generated 3D models of the male pelvic anatomy from hand-segmented color Visible Human Male cryosection data, reconstructed and visualized by Columbia University's in-house 3D Vesalius Visualizer.1 These 3D models depict the anatomy of the region in a realistic true-to-life color and texture. They can be used to create 3D anatomical scenes, with arbitrary complexity, where the component anatomical structures are displayed in correct 3D anatomical relationships. Moreover, a sequence of 3D scenes can be defined to simulate actual dissection. Structures can be added in a layered sequence from the bony framework to build from the "inside-out" or disassembled much like a true laboratory dissection from the "outside-in." These 3D reconstructed anatomical models can provide views of the structures from new perspectives and have the potential to improve understanding of the anatomical relationships of the pelvic region (http://www.cellbiology.lsuhsc.edu/People/Faculty/Venuti_Figures/movie_index.html)
Erratum: Identification of responsive cells in the developing somite supports a role for βâcateninâdependent Wnt signaling in maintaining the DML myogenic progenitor pool
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90355/1/23720_ftp.pd
Runx Expression Is Mitogenic and Mutually Linked to Wnt Activity in Blastula-Stage Sea Urchin Embryos
The Runt homology domain (Runx) defines a metazoan family of sequence-specific transcriptional regulatory proteins that are critical for animal development and causally associated with a variety of mammalian cancers. The sea urchin Runx gene SpRunt-1 is expressed throughout the blastula stage embryo, and is required globally during embryogenesis for cell survival and differentiation.Depletion of SpRunt-1 by morpholino antisense-mediated knockdown causes a blastula stage deficit in cell proliferation, as shown by bromodeoxyuridine (BrdU) incorporation and direct cell counts. Reverse transcription coupled polymerase chain reaction (RT-PCR) studies show that the cell proliferation deficit is presaged by a deficit in the expression of several zygotic wnt genes, including wnt8, a key regulator of endomesoderm development. In addition, SpRunt-1-depleted blastulae underexpress cyclinD, an effector of mitogenic Wnt signaling. Blastula stage cell proliferation is also impeded by knockdown of either wnt8 or cyclinD. Chromatin immunoprecipitation (ChIP) indicates that Runx target sites within 5Ⲡsequences flanking cyclinD, wnt6 and wnt8 are directly bound by SpRunt-1 protein at late blastula stage. Furthermore, experiments using a green fluorescent protein (GFP) reporter transgene show that the blastula-stage operation of a cis-regulatory module previously shown to be required for wnt8 expression (Minokawa et al., Dev. Biol. 288: 545â558, 2005) is dependent on its direct sequence-specific interaction with SpRunt-1. Finally, inhibitor studies and immunoblot analysis show that SpRunt-1 protein levels are negatively regulated by glycogen synthase kinase (GSK)-3.These results suggest that Runx expression and Wnt signaling are mutually linked in a feedback circuit that controls cell proliferation during development
Girls and Boys Born before 28Â Weeks Gestation: Risks of Cognitive, Behavioral, and Neurologic Outcomes at Age 10Â Years
To compare the prevalence of cognitive, neurological, and behavioral outcomes at 10 years of age in 428 girls and 446 boys who were born extremely preterm (EP)
The Relationship of Maternal Prepregnancy Body Mass Index and Pregnancy Weight Gain to Neurocognitive Function at Age 10 Years among Children Born Extremely Preterm
OBJECTIVE: To assess the association between maternal prepregnancy body mass index and adequacy of pregnancy weight gain in relation to neurocognitive function in school-aged children born extremely preterm.
STUDY DESIGN: Study participants were 535 ten-year-old children enrolled previously in the prospective multicenter Extremely Low Gestational Age Newborns cohort study who were products of singleton pregnancies. Soon after delivery, mothers provided information about prepregnancy weight. Prepregnancy body mass index and adequacy of weight gain were characterized based on this information. Children underwent a neurocognitive evaluation at 10 years of age.
RESULTS: Maternal prepregnancy obesity was associated with increased odds of a lower score for Differential Ability Scales-II Verbal IQ, for Developmental Neuropsychological Assessment-II measures of processing speed and visual fine motor control, and for Wechsler Individual Achievement Test-III Spelling. Children born to mothers who gained an excessive amount of weight were at increased odds of a low score on the Oral and Written Language Scales Oral Expression assessment. Conversely, children whose mother did not gain an adequate amount of weight were at increased odds of a lower score on the Oral and Written Language Scales Oral Expression and Wechsler Individual Achievement Test-III Word Reading assessments.
CONCLUSION: In this cohort of infants born extremely preterm, maternal obesity was associated with poorer performance on some assessments of neurocognitive function. Our findings are consistent with the observational and experimental literature and suggest that opportunities may exist to mitigate risk through education and behavioral intervention before pregnancy
Extremely low gestational age and very low birthweight for gestational age are risk factors for autism spectrum disorder in a large cohort study of 10-year-old children born at 23-27 weeksâ gestation
No prospective cohort study of high-risk children has used rigorous exposure assessment and optimal diagnostic procedures to examine the perinatal antecedents of autism spectrum disorder (ASD), separately among those with and without cognitive impairment
Nodal/activin signaling establishes oral-aboral polarity in the early sea urchin embryo
Components of the Wnt signaling pathway are involved in patterning the sea urchin primary or animal-vegetal (AV) axis, but the molecular cues that pattern the secondary embryonic axis, the aboral/oral (AO) axis, are not known. In an analysis of signaling molecules that influence patterning along the sea urchin embryonic axes, we found that members of the activin subfamily of transforming growth factor- (TGF-) signaling molecules influence the establishment of AO polarities in the early embryo. Injection of activin mRNAs into fertilized eggs or treatment with exogenously applied recombinant activin altered the allocation of ectodermal fates and ventralized the embryo. The phenotypes observed resemble the ventralized phenotype previously reported for NiCl2, a known disrupter of AO patterning. Sensitivity to exogenous activin occurs between fertilization and the late blastula stage, which is also the time of highest NiCl2 sensitivity. These results argue that specification of fates along the embryonic AO axis involves TGF- signaling. To further examine TGF- signaling in these embryos, we cloned an endogenous TGF- from sea urchin embryos that is a member of the activin subfamily, SpNodal, and show through gain of function analysis that it recapitulates results obtained with exogenous activins and NiCl2. The expression pattern of SpNodal is consistent with a role for nodal signaling in the establishment of fates along the AO axis. Loss of function experiments using SpNodal antisense morpholinos also support a role for SpNodal in the establishment of the AO axis