Conclusions: Human-rat geniculate ganglion (GG) have multiple origins: (1) An initial proximity (20 μm) to the endocranial foramen of the IAM, suggests neural crest induction; and (2) The influence of epibranchial placodes: the tensor tympani muscle (TTM) and the otic apical coil.
Objectives: This study was undertaken to determine the comparative development of human-rat GG.
Materials And Methods: A light microscopic study of the GG in human material obtained from spontaneous abortions at 9, 13, 14, 17, 18, and 30 weeks, and one neonate was done. This study examined Webster rat embryos and a post-natal series. Specimens were fixed in Bouin fluid, embedded in paraffin, cut, and stained with H&E. The histomorphometric data were obtained with image analysis software.
Results: The human fetus of 9 weeks presents two neuronal groups in the VII nerve: one near (20 μm) the IAM endocranial foramen, foraminal, and the other, tympanic. Neonate GG is located between the TTM and the cochlear apex (inwards). In the 16 day old rat embryo GG is placed within a canal containing the stapedial artery. In the adult rat the GG and the stapedial artery are placed within the IAM.
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http://dx.doi.org/10.1080/00016489.2016.1257867 | DOI Listing |
Mol Ther
January 2025
Faculty of Biology, Medicine & Health, University of Manchester, Manchester, M13 9PT, UK. Electronic address:
Optogenetic therapy is a promising vision restoration method where light sensitive opsins are introduced to the surviving inner retina following photoreceptor degeneration. The cell type targeted for opsin expression will likely influence the quality of restored vision. However, a like-for-like pre-clinical comparison of visual responses evoked following equivalent opsin expression in the two major targets, ON bipolar (ON BCs) or retinal ganglion cells (RGCs), is absent.
View Article and Find Full Text PDFCell Rep
January 2025
Center for Perceptual Systems, The University of Texas at Austin, Austin, TX 78712, USA; Center for Learning and Memory, The University of Texas at Austin, Austin, TX 78712, USA; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA. Electronic address:
The visual system adapts to maintain sensitivity and selectivity over a large range of luminance intensities. One way that the retina maintains sensitivity across night and day is by switching between rod and cone photoreceptors, which alters the receptive fields and interneuronal correlations of retinal ganglion cells (RGCs). While these adaptations allow the retina to transmit visual information to the brain across environmental conditions, the code used for that transmission varies.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Brain Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel.
Retinal ganglion cells (RGCs) typically respond to light stimulation over their spatially restricted receptive field. Using large-scale recordings in the mouse retina, we show that a subset of non- direction-selective (DS) RGCs exhibit asymmetric activity, selective to motion direction, in response to a stimulus crossing an area far beyond the classic receptive field. The extraclassical response arises via inputs from an asymmetric distal zone and is enhanced by desensitization mechanisms and an inherent DS component, creating a network of neurons responding to motion toward the optic disc.
View Article and Find Full Text PDFInt J Emerg Med
January 2025
Emergency Department, Taipei Veterans General Hospital, Taipei, 112, Taiwan.
Background: Ramsay Hunt syndrome (RHS), a rare complication of varicella-zoster virus (VZV) reactivation, presents with ipsilateral facial paralysis, ear pain, and vesicular rash. Early recognition is crucial for prompt treatment and optimal outcomes.
Case Presentation: We report a case of a 67-year-old woman with RHS who presented with right-sided facial palsy, severe ear pain, and fluid-filled blisters.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
January 2025
To exploring the value of MR neuroimaging for quantitative assessment of the facial nerve and peripheral lymph nodes in patients with acute peripheral facial paralysis. Based on a prospective experimental design, 32 patients with idiopathic peripheral facial palsy were enrolled in the experiment. Based on MR neuroimaging technology, MR high-resolution thin-layer images of bilateral facial nerves were acquired.
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