A new "naked-eye" and ratiometric fluorescent zinc sensor () of carboxamidoquinoline with 2-chloro-N-(quinol-8-yl)-acetamide as a receptor was designed and synthesized. The sensor shows good water solubility and high selectivity for sensing; about a 15-fold increase in fluorescence quantum yield and a 100 nm red-shift of fluorescence emission upon binding Zn(2+) in aqueous HEPES buffer solution are observed. The human lung cancer cell line (A549) activity is also demonstrated.

Of various chemosensory protocols, the color change observed by the naked eye is considered to be a conceivable and on-site way to indicate the presence of an analyte. We herein designed a ratiometric fluorescence probe by hybridizing dual-emission quantum dots (QDs) and demonstrated its efficiency for on-site visual determination of copper ions. The hybrid probe comprises two sizes of cadmium telluride QDs emitting red and green fluorescence respectively, in which the red-emitting ones are embedded in silica nanoparticles and the green-emitting ones are covalently linked onto the surface. The fluorescence of the embedded QDs is insensitive to analyte, whereas the green emissive QDs is functionalized to be selectively quenched by the analyte. Upon exposure to different amounts of copper ions, the variations of the dual emission intensity ratios display continuous color changes from green to red, which can be clearly observed by the naked eye. The limit of detection for copper is estimated to be 1.1 nM, much lower than the allowable level of copper (~20 µM) in drinking water setted by U.S. Environmental Protection Agency. The probe is demonstrated for the determination of copper ions in lake water and mineral water samples, especially for visually monitoring copper residues on herbs leaves. This prototype ratiometric probe is simple, fully self-contained, and thus potentially attractive for visual identification without the need for elaborate equipments.

PurposeTo evaluate and compare the diagnostic ability of spectral domain optical coherence tomography (SD-OCT) for detecting localized retinal nerve fiber layer (RNFL) defects in topographic RNFL maps and circumpapillary RNFL (cpRNFL) thickness measurements.MethodsSixty-four eyes with localized RNFL defects in red-free RNFL photographs and 72 healthy eyes were included. All participants were imaged with SD-OCT. The area and angular width of the localized RNFL defects were measured with ImageJ software on RNFL thickness map, significance map (yellow pixels, <5% level), and red-free RNFL photographs. The sensitivity, specificity, and area under the receiver operating characteristic curves (AUCs) were calculated for cpRNFL thickness, macular inner retina thickness, and RNFL maps (thickness, significance) according to the quantitative measurements and a <5% level of classification to distinguish eyes with localized RNFL defects from healthy eyes.ResultsRNFL thickness map (sensitivity 96.9-98.4%, specificity 86.1-98.6%, and AUCs 0.915-0.992) and significance map (sensitivity 96.9-98.4%, specificity 88.9-95.8%, and AUCs 0.937-0.983) showed superior performance in detecting localized RNFL defects compared with other parameters (P-value 0.001-0.024) except for 36 sector cpRNFL thickness (sensitivity 92.2%, specificity 87.5%, and AUCs 0.898; P-value 0.080-0.545). The sensitivity for detecting RNFL defects was related to the angular width, area, and depth of the RNFL defects in the cpRNFL (4 sector, 12 sector) and macular inner retinal measurements. RNFL thickness and significance maps showed a constant sensitivity regardless of variations in angular width, area, and depth of the RNFL defects.ConclusionRNFL thickness and significance maps could be used to distinguish eyes with localized RNFL defects from healthy eyes more effectively than cpRNFL thickness and macular inner retina thickness measurements.Eye advance online publication, 7 June 2013; doi:10.1038/eye.2013.119.

Purpose:

  Accumulation of bisretinoids as lipofuscin in retinal pigment epithelial (RPE) cells is implicated in the pathogenesis of some blinding diseases including age-related macular degeneration (AMD). To identify genes whose expression may change under conditions of bisretinoid accumulation, we investigated the differential gene expression in RPE cells that had accumulated the lipofuscin fluorophore A2E and were exposed to blue light (430 nm).

Methods:

  A2E-laden RPE cells were exposed to blue light (A2E/430 nm) at various time intervals. Cell death was quantified using Dead Red staining, and RNA levels for the entire genome was determined using DNA microarrays (Affymetrix GeneChip Human Genome 2.0 Plus). Array results for selected genes were confirmed by real-time reverse-transcriptase polymerase chain reaction.

Results:

  Principal component analysis revealed that the A2E-laden RPE cells irradiated with blue light were clearly distinguishable from the control samples. We found differential regulation of genes belonging to the following functional groups: transcription factors, stress response, apoptosis and immune response. Among the last mentioned were downregulation of four genes that coded for proteins that have an inhibitory effect on the complement cascade: (complement factor H, complement factor H-related 1, complement factor I and vitronectin) and of two belonging to the classical pathway (complement component 1, s subcomponent and complement component 1, r subcomponent).

Conclusion:

  This study demonstrates that blue light irradiation of A2E-laden RPE cells can alter the transcription of genes belonging to different functional pathways including stress response, apoptosis and the immune response. We suggest that these molecules may be associated to the pathogenesis of AMD and can potentially serve as future therapeutic targets.

Purpose.

To investigate the pupillary light reflex (PLR) of patients with severe loss of vision due to Leber's Hereditary Optic Neuropathy (LHON) in the context of a proposed preservation of melanopsin-expressing retinal ganglion cells (mRGCs). Methods. Ten LHON patients (7 M; 51.6 ±14.1 yo) with visual acuities ranging from 20/400 to hand motion perception and severe visual field losses were tested and compared to 16 healthy subjects (7 M; 42.15 ±15.4 yo) tested as controls. PLR was measured with an eye tracker and the stimuli were controlled with a Ganzfeld system. Pupil responses were measured monocularly, to 1 s of blue (470 nm) and red (640 nm) flashes with 1, 10, 100 and 250 cd/m2 luminances. The normalized amplitude of peak of the transient PLR and the amplitude of the sustained PLR at 6 s after the flash offset were measured. In addition, optical coherence topography (OCT) scans of the peripapillary retinal nerve fiber layer were obtained.

Results.

The patient's peak PLR responses were on average 15% smaller than controls (p<0.05), but 5 out of 10 patients had amplitudes within the range of controls. The patients' sustained PLRs were comparable to controls at lower flash intensities, but on average 27% smaller to the 250 cd/m2 blue light, although there was considerable overlap with the PLR amplitudes of control. All patients had severe visual field losses and the retinal nerve fiber layer thickness was reduced to a minimum around the optic disc in 8 of the 10 patients.

Conclusions.

The PLR is maintained overall in LHON patients despite the severity of optic atrophy. These results are consistent with previous evidence of selective preservation of mRGCs.

No abstract available.

Objective:

Eye diseases including cataract, keratitis and pterygium have been reported to be sun-exposure-related. The association between macular degeneration and blue light has also been discussed. Moreover, it is hypothesized that retinal exposure to blue light may influence the human circadian rhythm. However, no monitoring devices exist that can measure eye exposure to visible and ultraviolet (UV) radiation over time. To measure the exact dose at specific times, we have developed a novel sensing system (ray-sensing glass system: RaySeG).

Methods:

RaySeG can continuously measure and record the composition and intensity of light with a time-stamped system. Subjects wearing RaySeG were instructed to walk under various light conditions such as indoor and outdoor.

Results:

RaySeG consists of two sensors embedded in the eyeglasses. These sensors are for UV (260-400 nm), visible lights (red, 615 nm; green, 540 nm; and blue, 465 nm: peak wavelength for each). The total weight of the system is about 100 g, and the size is comparable to that of a digital audio player. The system continuously recorded changes in visible and UV light exposure under various conditions.

Conclusions:

After accuracy validation, further experiments with a larger number of subjects are required. Our final goal is to apply the system to evaluating personal eye exposure to UV and visible light in epidemiological studies of eye diseases and circadian rhythm abnormality.

The intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin, which is sensitive to blue light. Previous chromatic pupillometry studies have shown that the post-illumination response is considered an indicator of the melanopsin activation. The aim of this study was to investigate the ipRGC mediated pupil response in patients with a unilateral non-arteritic anterior ischemic optic neuropathy (NAION). Consensual pupil responses during and after exposure to continuous 20 s blue (470 nm) or red (660 nm) light of high intensity (300 cd/m(2)) were recorded in each eye for 10 patients. Comparisons were performed both intra-individually (affected versus non-affected eyes) and inter-individually (compared with healthy controls). The pupil response was calculated both during the illumination and during the post-illumination phase. The pupil responses to blue and red colors were significantly reduced in the NAION-affected eyes, compared with the fellow non-affected eyes. When comparing the affected eyes with the healthy control eyes, the post-illumination responses were not significantly different. In addition, the post-illumination pupil responses after blue light exposure were increased in the fellow non-affected patients' eyes, compared with the healthy controls. However, significance was only reached for the late post-illumination response. In conclusion, chromatic pupillometry disclosed reduced post-illumination pupil responses in the NAION-affected eyes, compared with the non-affected fellow eyes, suggesting dysfunction of the ipRGCs. Compared with the responses of the healthy controls, the blue light post-illumination pupil responses were similar in the affected eyes and increased in the fellow non-affected eyes. This suggests a possible adaptive phenomenon, involving the ipRGCs of both eyes after unilateral NAION.

The current inquiry was conducted to assess the change in sleep architecture after long periods of administration to determine whether ginseng can be used in the therapy of sleeplessness. Following post-surgical recovery, red ginseng extract (RGE, 200 mg/ kg) was orally administrated to rats for 9 d. Data were gathered on the 1st, 5th, and 9th day, and an electroencephalogram was recorded 24 h after RGE administration. Polygraphic signs of unobstructed sleep-wake activities were simultaneously recorded with sleep-wake recording electrodes from 11:00 a.m. to 5:00 p.m. for 6 h. Rodents were generally tamed to freely moving polygraphic recording conditions. Although the 1st and 5th day of RGE treatment showed no effect on power densities in non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, the 9th day of RGE administration showed augmented α-wave (8.0 to 13.0 Hz) power densities in NREM and REM sleep. RGE increased total sleep and NREM sleep. The total percentage of wakefulness was only decreased on the 9th day, and the number of sleep-wake cycles was reduced after the repeated administration of RGE. Thus, the repeated administration of RGE increased NREM sleep in rats. The α-wave activities in the cortical electroencephalograms were increased in sleep architecture by RGE. Moreover, the levels of both α- and β-subunits of the γ-aminobutyric acid (GABA)A receptor were reduced in the hypothalamus of the RGE-treated groups. The level of glutamic acid decarboxylase was over-expressed in the hypothalamus. These results demonstrate that RGE increases NREM sleep via GABAAergic systems.

We introduce a case of blindness after a periorbital fat graft and its resulting court ruling in regard to a surgeon's liability of compensation. A 19-year-old woman received an injection of preserved autologous fat to her nasal dorsum. During the injections, she complained of pain and lost vision of her right eye. The pupil responded to light but showed a blepharoptosis and a limitation of the extraocular muscle of her right eye. Upon a fundoscopy, a cherry red spot was observed. Brain magnetic resonance imaging and angiography showed an acute infarction of the ophthalmic nerve. Upon an angio-computed tomography, the ophthalmic artery branch was not visualized. Her right eye remained blind 3 weeks after admission. She claimed compensation for damage from the surgeon. The court determined a ruling in favor of the plaintiff (patient); however, the responsibility was limited to 70%. As a result, the defendant has to pay 84,750 US$ to the patient and 6450 US$ to her parents. Roe (the presiding judge) stated that in this case, the injected autologous fat seems to have been put into the ophthalmic artery and the central retinal artery along the vascular countercurrent because of excessive applied pressure. The court also said that because the plaintiff had a history of rhinoplasty, the defendant should have injected the fat more slowly at low pressure to avoid the vascular injury. We think there is a question about "how slowly and how low the pressure should be" for the fat injection. A further study of injection pressure, particle size, temperature, and release in the amount of fat for safe, periorbital, fat grafts should follow this study.