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Purpose: Intraocular pressure (IOP) is currently the only modifiable risk factor for glaucoma, yet glaucoma can continue to progress despite controlled IOP. Thus, development of glaucoma neurotherapeutics remains an unmet need. Scutellarin is a flavonoid that can exert neuroprotective effects in the eye and brain. Here, we investigated the neurobehavioral effects of scutellarin treatment in a chronic IOP elevation model.Methods: Ten adult C57BL/6J mice were unilaterally injected with an optically clear hydrogel into the anterior chamber to obstruct aqueous outflow and induce chronic IOP elevation. Eight other mice received unilateral intracameral injection of phosphate-buffered saline only. Another eight mice with hydrogel-induced unilateral chronic IOP elevation also received daily oral gavage of 300 mg/kg scutellarin. Tonometry, optical coherence tomography, and optokinetics were performed longitudinally for 4 weeks to monitor the IOP, retinal nerve fiber layer thickness, total retinal thickness, visual acuity, and contrast sensitivity of both eyes in all three groups.Results: Intracameral hydrogel injection resulted in unilateral chronic IOP elevation with no significant inter-eye IOP difference between scutellarin treatment and untreated groups. Upon scutellarin treatment, the hydrogel-injected eyes showed less retinal thinning and reduced visual behavioral deficits when compared to the untreated, hydrogel-injected eyes. No significant difference in retinal thickness or optokinetic measures was found in the contralateral, non-treated eyes over time or between all groups.Conclusion: Using the non-invasive measuring platform, oral scutellarin treatment appeared to preserve retinal structure and visual function upon chronic IOP elevation in mice. Scutellarin may be a novel neurotherapeutic agent for glaucoma treatment.

Understanding the mechanisms of vision in health and disease requires knowledge of the anatomy and physiology of the eye and the neural pathways relevant to visual perception. As such, development of imaging techniques for the visual system is crucial for unveiling the neural basis of visual function or impairment. Magnetic resonance imaging (MRI) offers non-invasive probing of the structure and function of the neural circuits without depth limitation, and can help identify abnormalities in brain tissues in vivo. Among the advanced MRI techniques, manganese-enhanced MRI (MEMRI) involves the use of active manganese contrast agents that positively enhance brain tissue signals in T1-weighted imaging with respect to the levels of connectivity and activity. Depending on the routes of administration, accumulation of manganese ions in the eye and the visual pathways can be attributed to systemic distribution or their local transport across axons in an anterograde fashion, entering the neurons through voltage-gated calcium channels. The use of the paramagnetic manganese contrast in MRI has a wide range of applications in the visual system from imaging neurodevelopment to assessing and monitoring neurodegeneration, neuroplasticity, neuroprotection, and neuroregeneration. In this review, we present four major domains of scientific inquiry where MEMRI can be put to imperative use — deciphering neuroarchitecture, tracing neuronal tracts, detecting neuronal activity, and identifying or differentiating glial activity. We deliberate upon each category studies that have successfully employed MEMRI to examine the visual system, including the delivery protocols, spatiotemporal characteristics, and biophysical interpretation. Based on this literature, we have identified some critical challenges in the field in terms of toxicity, and sensitivity and specificity of manganese enhancement. We also discuss the pitfalls and alternatives of MEMRI which will provide new avenues to explore in the future.

A qualitative study on impact of pre-disaster public awareness activities on public readiness was conducted in the North and South Pagai Islands after the 25 October 2010 Mentawai earthquake. Parameters of readiness are public response to tsunami and the number of casualties. The results show that public awareness activities that commenced from 2004 have effectively increased people's awareness of tsunamis as indicated by their knowledge of tsunami signals. Yet apart from failure of the official warning system to alert the public in remote areas, the response of people to the natural tsunami signals has been made on the basis of misperceptions of strong earthquake signals and tsunami lead-time. Tsunami lead-time of the Pagai Islands had been perceived as long as that of Sumatra or Java Islands and strong earthquakes have been perceived as merely strong ground shaking. These misperceptions came from invalid materials of public education and invalid translation of scientific information, and were confirmed by people's experiences in the 12 September 2007 Bengkulu earthquake. Hence, despite mitigation by relocating houses to the high ground that has saved many lives in Malakopa and Asahan, there is no evidence on the positive relation of pre-disaster awareness intervention with the reduction in loss of lives in the study sites. In order to not give invalid information on tsunami awareness in the future, instead of using a generic formula of regional tsunamis, public education on tsunami should use a specific formula based on local characteristics. Moreover, sensing earthquakes that may trigger tsunamis through the duration of ground shaking may be more effective than that of the strength of ground shaking. Because sensing time duration is difficult, particularly for communities that are not used to using modern timers, it is necessary to develop simple means of sensing time duration.