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Posterior Chamber (posterior + chamber)
Selected AbstractsMorphology and histology of the larynx of the common toad Rhinella arenarum (Hensel, 1867) (Anura, Bufonidae)ACTA ZOOLOGICA, Issue 4 2009Gladys N. Hermida Abstract The structure of the larynx of the toad Rhinella arenarum was exhaustively studied. The laryngeal skeleton consists of three bilaterally symmetrical cartilages: the cricoid and two arytenoids. Internally, each half-larynx has an anterior and a posterior chamber. The first chamber is delimited by the epithelium covering the arytenoid cartilage and the anterior membrane. The latter consists of fibro-elastic tissue and contains blood capillaries that, judging by their location and distribution, might serve to maintain vocal cord turgidity. At the level of the cricoid cartilage, two structures are reported here for the first time: the posterodorsal and the anteroventral processes. Both processes are associated with the insertion of the posterior membrane. A cartilaginous rod is located at the free margin of the posterior membrane. This rod appears to support the membrane when the air flows. The distal portion of the larynx communicates with the proximal region of the lung. The epithelium of the laryngeal mucosa contains ciliated cells, goblet cells, secretory cells with short microvilli and neuroendocrine cells immunopositive to PGP 9.5. The results obtained in this study provide new information about the internal organization of the larynx in anurans, which could serve as additional morphological characters for phylogenetic relationships. [source] Development of the swimbladder and its innervation in the zebrafish, Danio rerioJOURNAL OF MORPHOLOGY, Issue 11 2007G.N. Robertson Abstract Many teleosts including zebrafish, Danio rerio, actively regulate buoyancy with a gas-filled swimbladder, the volume of which is controlled by autonomic reflexes acting on vascular, muscular, and secretory effectors. In this study, we investigated the morphological development of the zebrafish swimbladder together with its effectors and innervation. The swimbladder first formed as a single chamber, which inflated at 1,3 days posthatching (dph), 3.5,4 mm body length. Lateral nerves were already present as demonstrated by the antibody zn-12, and blood vessels had formed in parallel on the cranial aspect to supply blood to anastomotic capillary loops as demonstrated by Tie-2 antibody staining. Neuropeptide Y-(NPY-) like immunoreactive (LIR) fibers appeared early in the single-chambered stage, and vasoactive intestinal polypeptide (VIP)-LIR fibers and cell bodies developed by 10 dph (5 mm). By 18 dph (6 mm), the anterior chamber formed by evagination from the cranial end of the original chamber; both chambers then enlarged with the ductus communicans forming a constriction between them. The parallel blood vessels developed into an arteriovenous rete on the cranial aspect of the posterior chamber and this region was innervated by zn-12-reactive fibers. Tyrosine hydroxylase- (TH-), NPY-, and VIP-LIR fibers also innervated this area and the lateral posterior chamber. Innervation of the early anterior chamber was also demonstrated by VIP-LIR fibers. By 25,30 dph (8,9 mm), a band of smooth muscle formed in the lateral wall of the posterior chamber. Although gas in the swimbladder increased buoyancy of young larvae just after first inflation, our results suggest that active control of the swimbladder may not occur until after the formation of the two chambers and subsequent development and maturation of vasculature, musculature and innervation of these structures at about 28,30 dph. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Longitudinal study of anterior segment inflammation by ultrasound biomicroscopy in patients with acute anterior uveitisACTA OPHTHALMOLOGICA, Issue 2 2009Yang Peizeng Abstract. Purpose:, This study aimed to investigate dynamic changes in the anterior segment in patients with acute anterior uveitis (AAU) using ultrasound biomicroscopy (UBM). Methods:, Acute anterior uveitis was diagnosed in 18 patients according to history and ocular examinations. Ultrasound biomicroscopy was performed and the results at three time-points (within 2 weeks of the uveitis attack, and at 2,4 weeks and 6 weeks after it) were analysed. The relationships between clinical manifestations and UBM findings were also evaluated. Results:, All investigated AAU patients showed severe ciliary injection, numerous dust keratic precipitates (KPs), aqueous flare and inflammatory cells, and were treated predominantly with corticosteroid and cycloplegic eyedrops. Ultrasound biomicroscopy showed a large number of cells in the anterior and posterior chamber, marked oedema and exudates in and around the iris and ciliary body within 2 weeks of AAU onset. These abnormalities were dramatically improved at 2,4 weeks and almost resolved at 6 weeks and thereafter. Conclusions:, Ultrasound biomicroscopy reveals severe inflammatory changes in and around the ciliary body in patients with AAU. These signs rapidly resolve upon treatment. [source] Feline immunodeficiency virus vectors.THE JOURNAL OF GENE MEDICINE, Issue 5 2002Gene transfer to mouse retina following intravitreal injection Abstract Background Transduction of the murine retinal pigmented epithelium (RPE) with adenovirus vectors requires technically difficult and invasive subretinal injections. This study tested the hypothesis that recombinant vectors based on feline immunodeficiency virus (FIV) could access the retina following intravitreal injection. Methods FIV vectors expressing E. coli ,-galactosidase (FIV,gal) were injected alone, or in combination with adenovirus vectors expressing eGFP, into the vitreous of normal mice and eyes evaluated for transgene expression. In further studies, the utility of FIV-mediated gene transfer to correct lysosomal storage defects in the anterior and posterior chambers of eyes was tested using recombinant FIV vectors expressing ,-glucuronidase. FIV,gluc vectors were injected into ,-glucuronidase-deficient mice, an animal model of mucopolysacharridoses type VII. Results The results of this study show that similar to adenovirus, both corneal endothelium and cells of the iris could be transduced following intravitreal injection of FIV,gal. However, in contrast to adenovirus, intravitreal injection of FIV,gal also resulted in transduction of the RPE. Immunohistochemistry following an intravitreal injection of an AdeGFP (adenovirus expressing green fluorescent protein) and FIV,gal mixture confirmed that both viruses mediated transduction of corneal endothelium and cells of the iris, while only FIV,gal transduced cells in the retina. Using the ,-glucuronidase-deficient mouse, the therapeutic efficacy of intravitreal injection of FIV,gluc (FIV expressing ,-glucuronidase) was tested. Intravitreal injection of FIV,gluc to the eyes of ,-glucuronidase-deficient mice resulted in rapid reduction (within 2,weeks) of the lysosomal storage defect within the RPE, corneal endothelium, and the non-pigmented epithelium of the ciliary process. Transgene expression and correction of the lysosomal storage defect remained for at least 12,weeks, the latest time point tested. Conclusion These studies demonstrate that intravitreal injection of FIV-based vectors can mediate efficient and lasting transduction of cells in the cornea, iris, and retina. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||