The ocelli of Archaeognatha, or jumping bristletails, differ from typical insect ocelli in shape and field of view. Although the shape of the lateral ocelli is highly variable among species, most Machiloidea have sole-shaped lateral ocelli beneath the compound eyes and a median ocellus that is oriented downward. This study investigated morphological and physiological aspects of the ocelli of Machilis hrabei and Lepismachilis spp. The light-reflecting ocellar tapetum in M. hrabei is made up of xanthine nanocrystals, as demonstrated by confocal Raman spectroscopy. Pigment granules in the photoreceptor cells move behind the tapetum in the dark-adapted state. Such a vertical pigment migration in combination with a tapetum has not been described for any insect ocellus so far. The pigment migration has a dynamic range of approximately 4 log units and is maximally sensitive to green light. Adaptation from darkness to bright light lasts over an hour, which is slow compared with the radial pupil mechanism in some dragonflies and locusts.
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http://dx.doi.org/10.1242/jeb.141275 | DOI Listing |
Sci Rep
January 2025
Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan Province, People's Republic of China.
Epithelial‒mesenchymal transition (EMT) in retinal pigment epithelial (RPE) cells is believed to play a key role in the pathogenesis of proliferative vitreoretinopathy (PVR). The ability of Hirudo to promote blood flow and dispel blood stasis may be related to its anti-EMT effects. Through the use of a network pharmacology method, the mechanism by which Hirudo treats PVR was investigated in this study, and the findings were confirmed through in vitro cellular tests.
View Article and Find Full Text PDFExp Eye Res
January 2025
Department of Ophthalmology, First Affiliated Hospital, Zhejiang University School of Medicine, 310003, China. Electronic address:
Senescent retinal pigment epithelial cells play a key role in neovascular age-related macular degeneration (nAMD); however, the mechanisms underlying the angiogenic ability of these cells remain unclear. Herein, we investigated the effects of the senescent adult retinal pigment epithelial cell line-19 (ARPE-19) on wound healing, cell migration and survival, and tube formation abilities of human umbilical vein endothelial cells (HUVECs). Additionally, we used Brown Norway rats to establish a laser-induced choroidal neovascularization (CNV) model for further nAMD-related studies.
View Article and Find Full Text PDFAntioxidants (Basel)
December 2024
Development, Ageing and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK.
Reactive oxygen species (ROS) within the retina play a key role in maintaining function and cell survival. However, excessive ROS can lead to oxidative stress, inducing dysregulation of metabolic and inflammatory pathways. The zebrafish models choroideremia (CHM), an X-linked chorioretinal dystrophy, which predominantly affects the photoreceptors, retinal pigment epithelium (RPE), and choroid.
View Article and Find Full Text PDFJ Cancer
January 2025
Department of Ophthalmology, Southwest Hospital, The Third Military Medical University (Army Medical University), Chongqing, P.R. China.
Uveal melanoma (UM) has emerged as one of the most common primary intraocular malignant tumors worldwide. Long non-coding RNAs (lncRNAs) are increasingly recognized as decisive factors in the progression and metastasis of UM, involving in epithelial-mesenchymal transition (EMT) of UM. We conducted a comprehensive analysis of lncRNAs closely associated with EMT-related genes in the TCGA UM cohort, identifying 961 EMT-related lncRNAs.
View Article and Find Full Text PDFJ Vitreoretin Dis
December 2024
Associated Retinal Consultants, Royal Oak, MI, USA.
To present a pediatric patient with a unique configuration of torpedo maculopathy complicated by macular choroidal neovascularization (CNV). A single case was retrospectively reviewed. An 8-year-old male child presented with decreased vision in the left eye and was found to have 2 distinct torpedo maculopathy lesions, 1 a smaller hypopigmented lesion in the temporal parafovea and the other a larger hyperpigmented comet-shaped lesion in the temporal periphery.
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