Prospective study on retinal nerve fibre layer changes after an acute episode of phacomorphic angle closure

To investigate the retinal nerve fibre layer (RNFL) changes after an acute attack of phacomorphic angle closure. This prospective study involved ten cases of phacomorphic angle closure that underwent cataract extraction and intraocular lens insertion after intraocular pressure lowering. Apart from visual acuity and intraocular pressure (IOP), RNFL thickness and vertical cup disc ratio (VCDR) were measured by optical coherence tomography (OCT) at 3-9 months post attack. Humphrey visual field assessment was performed at 9 months post attack. All cases had mean phacomorphic duration of  0.2. Patients with <5 days duration of phacomorphic angle closure are likely to have reasonable postoperative vision. An acute episode of phacomorphic angle closure can trigger an accelerated RNFL thinning despite normal IOP and open angles, most noticeable in the superior and inferior quadrants, occurring between 3 and 9 months post attack. Glaucomatous optic neuropathy in the attack eye was evident by OCT but not by visual field assessment at the same time interval. © 2012 The Author(s).published_or_final_versio

Argon laser peripheral iridoplasty versus systemic intraocular pressure-lowering medications as immediate management for acute phacomorphic angle closure.

Background: The purpose of this study was to compare the efficacy and safety of argon laser peripheral iridoplasty (ALPI) and systemic intraocular pressure (IOP)-lowering medications in the immediate management of acute phacomorphic angle closure. Methods: Consecutive cases of acute phacomorphic angle closure were randomized to receive ALPI and an intravenous or oral carbonic anhydrase inhibitor as initial treatment. Intravenous mannitol was administered for presenting IOP > 60 mmHg or IOP > 40 mmHg 2 hours posttreatment in both arms. Results: Of 10 consecutive cases, six received medical therapy and four received ALPI. Fifty percent in the medical group and none in the ALPI group required intravenous mannitol. The ALPI group took less time to achieve IOP < 25 mmHg (18.8 ± 7.5 minutes versus 115.0 ± 97.0 minutes, P = 0.001, F test); had a greater IOP reduction within 30 minutes (69.8% ± 7.7% versus 40.9 ± 23.9%, P = 0.03, t-test); and had a consistently smaller post-attack cup to disc ratio (0.50 ± 0.02 versus 0.60 ± 0.20, P = 0.002, F test). Conclusion: ALPI offers greater safety, consistency, and efficacy than systemic IOP-lowering medications as initial treatment for phacomorphic angle closure. © 2013 Lee et al, publisher and licensee Dove Medical Press Ltd.published_or_final_versio

Differences in risk factors for retinopathy of prematurity development in paired twins: A Chinese population study

2014-2015 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Androgen and retinoic acid interaction in LNCaP cells, effects on cell proliferation and expression of retinoic acid receptors and epidermal growth factor receptor

BACKGROUND: Modulation of the expression of retinoic acid receptors (RAR) α and γ in adult rat prostate by testosterone (T) suggests that RAR signaling events might mediate some of the androgen effects on prostate cells. METHOD: In this study, we examined the interactions between T and retinoic acid (RA) in cell growth of human prostate carcinoma cells, LNCaP, and their relationship with the expression of RAR and epidermal growth factor receptor (EGF-R). RESULTS: Both T and RA, when administered alone, stimulated (3)H-thymidine incorporation in LNCaP cells in a dose-dependent manner; the effect of each agent was reciprocally attenuated by the other agent. Testosterone treatment of LNCaP cells also resulted in dose dependent, biphasic increases in RAR α and γ mRNAs; increases paralleled that of (3)H-thymidine incorporation and were attenuated by the presence of 100 nM RA. These results suggest a link between RAR signaling and the effect of T on LNCaP cell growth. Gel electrophoretic mobility shift assays revealed the presence of putative androgen responsive element (ARE) in the promoter region of RAR α gene, suggesting that a direct AR-DNA interaction might mediate the effects of T on RAR α gene. Furthermore, treatment of LNCaP cells with 20 nM T resulted in an increase in EGF-R. In contrast, EGF-R was suppressed by 100 nM RA that also suppressed the effect of T. CONCLUSIONS: Current results demonstrate interactions between T and RA in the expression of RARs and cell growth in LNCaP cells. The presence of putative ARE in the promoter of the RAR α gene suggests that AR-DNA interaction might mediate the effects of T on RAR α gene. The opposite effects of T and RA on the expression of RAR and EGF-R suggest that signal events of these receptors might be involved in the interaction between T and RA in the control of LNCaP cell growth

Neuromyelitis optica spectrum disorder in a chinese woman with ocular myasthenia gravis: First reported case in the chinese population

Coexisting myasthenia gravis and neuromyelitis optica spectrum disorder was reported as a rare association, with only 26 reported cases in the literature. The authors report the case of a middle-aged Chinese woman with bilateral recurrent optic neuritis and seropositive ocular myasthenia gravis who was subsequently diagnosed with neuromyelitis optica spectrum. She was tested seropositive for the neuromyelitis optica immunoglobulin G (NMO-IgG) and had elevated antinuclear antibody titres, but workup for other autoimmune disorders were negative. She was subsequently prescribed with azathioprine and pyridostigmine, and showed good control of both autoimmune disorders. To the best of the authors' knowledge, this is the first reported case in the literature of a Chinese patient with seropositivity for both anti-acetylcholine receptor and NMO-IgG without a thymic disorder. Testing of NMO-IgG may be considered in patients with optic neuritis with underlying autoimmune disorders even in the absence of transverse myelitis for the detection of associated neuromyelitis optica spectrum disorders. © 2014 Informa Healthcare USA, Inc. All rights reserved: reproduction in whole or part not permitted

Inflammatory and intraocular pressure outcomes after trabeculectomy in active uveitic glaucoma in Chinese

AIM: To analyze the outcomes in uveitic activity and intraocular pressure(IOP)control after trabeculectomy for uveitis with uncontrolled IOP. METHODS: The medical records of consecutive uveitic glaucoma patients undergoing trabeculectomy between October 2006 to March 2011 were retrospectively reviewed. Uveitic activity, frequency of recurrence, steroid dependence, and intraocular pressure control were compared with paired t-test before and after trabeculectomy. RESULTS: In 29 eyes from 29 patients, 90% of eyes were on topical steroids at the time of trabeculectomy. The mean age was 58.3±14.0 years old with a pre-operative IOP of 35.7±8.9mmHg. The mean follow up time was 35.2±18.7mo. There was a reduction of anterior chamber activity grading of 0.4±0.6(P<0.01)at 3mo post-operatively. The uveitis recurrence rate was significantly reduced by 2.3±2.1 episodes/year(P<0.01)during the follow-up period. The mean 1y post-trabeculectomy IOP was 13.1±4.5mmHg with 44.8% of eyes with IOP≤21mmHg without medication. CONCLUSION: Uveitic activity and IOP control improved after trabeculectomy with a lower success rate to primary glaucomas. Trabeculectomy may be considered as a possible early intervention of active uveitis with high IOP for pressure and uveitic activity control.link_to_OA_fulltex

Longitudinal changes in retinal nerve fibre layer thickness after an isolated unilateral retrobulbar optic neuritis: 1-Year results

The objective of this study was to investigate the longitudinal changes in retinal nerve fibre layer (RNFL) thickness 1 year after an episode of unilateral acute optic neuritis. This prospective cohort study recruited consecutive patients with a first episode of isolated, unilateral acute optic neuritis from October 2010 to June 2013. RNFL thickness of the attack and normal fellow eyes was measured by optical coherence tomography on presentation and 3, 6, and 12 months post attack in both the treatment and non-treatment groups. The treatment group consisted of subjects that opted for systemic steroids to hasten recovery time. In 20 subjects, 11 received systemic steroids and 9 were treated conservatively. The baseline RNFL thickness was similar in the attack and fellow eyes (p≥0.4). Progressive RNFL thinning was seen in the attack eye over the 12-month period, with significant differences for baseline versus 3 months; baseline versus 12 months; and 3 versus 12 months (all p<0.0001). At 12 months, the attack eye had a thinner average RNFL than the fellow eye (100.9±6.1 versus 107.3±5.5 μm; p=0.002). The 12-month RNFL was similar between the treatment and non-treatment groups (p≥0.6). A single episode of optic neuritis triggered an accelerated, progressive RNFL thinning up to 6 months post attack. Initial treatment with systemic steroids did not seem to alter the degree of RNFL loss at 12 months

Blockade of non-opioid excitatory effects of spinal Dynorphin A at bradykinin receptors

Dynorphin A (Dyn A) is an endogenous opioid peptide that produces neuroinhibitory (antinociceptive) effects via m, d, and k opioid receptors. However, under chronic pain conditions, up-regulated spinal Dyn A can also interact with bradykinin receptors (BRs) to promote hyperalgesia through a neuroexcitatory (pronociceptive) effect. &nbsp;These excitatory effects cannot be blocked by an opioid antagonist, and thus are non-opioid in nature. Considering the structural dissimilarity between Dyn A and endogenous BR ligands, bradykinin (BK) and kallidin (KD), this interaction could not be predicted, and provided an opportunity to discover a novel potential neuroexcitatory target. Systematic structure-activity relationship (SAR) studies discovered a minimum pharmacophore of Dyn A, [des-Arg7]-Dyn A-(4-11) LYS1044 for antagonist activity at the BRs, along with insights into the key structural features for BRs recognition, i.e., amphipathicity. &nbsp;The des-Tyr fragment of dynorphin does not bind to opioid receptors.&nbsp; Intrathecal administration of des-Tyr dynorphin produces hyperalgesia reminiscent of behaviors seen in peripheral neuropathic pain models and at higher doses, neurotoxicity. Our lead ligand LYS1044 blocked Dyn A-(2-13)-induced neuroexcitatory effects in naïve animals and reversed thermal hyperalgesia and mechanical hypersensitivity in a dose-dependent manner in animals with experimental neuropathic pain. Based on these results, ligand LYS1044 might inhibit abnormal pain states by blocking the neuroexcitatory effects of enhanced levels of Dyn A that are seen in experimental models of neuropathic pain and that likely promote excitation mediated by BRs in the spinal cord