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Perrault syndrome 5 is a rare autosomal recessive disorder that is characterized by the association of sensorineural hearing loss and ovarian dysgenesis in females with diversity of neurologic deficits due to variants of twinkle mtDNA helicase (TWNK) gene. Since neurologic deficits develop gradually, patient is often misdiagnosed with other neurological disease during early age. Herein, we report a case of genetically diagnosed Perrault syndrome 5.

Most common methods of cellular analysis employ the top-down approach (investigating proteomics or genomics directly), thereby destroying the cell, which does not allow the possibility of using the same cell to correlate genomics with functional assays. Herein we describe an approach for single-cell tools that serve as a bottom-up approach. Our technology allows functional phenotyping to be conducted by observing the cytotoxicity of cells and then probe the underlying biology. We have developed a droplet microfluidic device capable of trapping droplets in the array and releasing the droplet of interest selectively using microvalves. Each droplet in the array encapsulates natural killer cells (NK cells) and tumour cells for real-time monitoring of burst kinetics and spatial coordination during killing by single NK cells. Finally, we use the microvalve actuation to selectively release droplets with the desired functional phenotype such as for fast and serial killing of target tumour cells by NK cells. From this perspective, our device allows for investigating first interactions and real-time monitoring of kinetics and later cell recovery on demand for single-cell omic analysis such as single-cell RNA sequencing (scRNA), which to date, is primarily based on in-depth analyses of the entire transcriptome of a relatively low number of cells.

The early detection of mercury ions in water sources should be emphasized to prevent human exposure to mercury through drinking water or food consumption. Here, we used a three-dimensional (3D)-printed multiarray chip to achieve colorimetric detection of inorganic mercury ions in environmental matrices such as lake water. The chip designed for the multidetection of inorganic mercury did not require an electrical syringe pump or a complex analytical system, thereby making it suitable for on-site detection. The chip could detect inorganic mercury ions via rolling circle amplification, by selectively harnessing thymine-Hg2+-thymine coordination chemistry. Additionally, the activities of rolling circle amplification in simple and environmental matrices were compared. The limits of detection for inorganic mercury ions were 3.4 and 4.1 µg/L in the simple and environmental matrices, respectively. Further, the chip was successfully applied for the detection of mercury in actual lake water samples collected from locations nearby inland fish farms. The results were quantitatively comparable to those obtained using a conventional mercury analyzer.

In the present study, an aptamer-based fluorescent assay was developed to detect fipronil in liquid eggs, using a carboxyfluorescein (FAM)-labeled aptamer (FAM aptamer) and partially complementary DNA labeled with carboxytetramethylrhodamine (TAMRA cDNA). The fipronil amount in analytical samples was determined by measuring FAM fluorescence at 522 nm. In the absence of fipronil, FAM fluorescence is effectively quenched by fluorescence resonance energy transfer (FRET) phenomenon generated by the hybridized structure of the FAM aptamer and TAMRA cDNA. In contrast, in the presence of fipronil, FAM fluorescence is gradually recovered in a fipronil concentration-dependent manner because the FAM aptamer has a stronger affinity for fipronil than for TAMRA cDNA. The proposed analytical method for fipronil involves a simple one-step procedure of mixing the sample solution without any washing step, and the results can be obtained in approximately 30 min. Under optimized conditions, the developed assay showed a linear response to fipronil in the egg sample in the range of 25-300 ppb with a detection limit of 53.8 ppb (0.068 mg/kg) and recovery rates in the range of 94.7-114.4%. Additionally, the assay selectivity for fipronil was investigated against eight pesticides, and it showed good specificity for fipronil. Compared with conventional liquid chromatography-mass spectrometry (LC-MS), the proposed method provides a simple, easy, and fast method to detect fipronil in egg samples without requiring bulky and expensive instruments and complicated and laborious processes. We believe this detection method could be a promising platform for fipronil detection in real food samples.

Screening target microorganisms from a mutated recombinant library plays a crucial role in advancing synthetic biology and metabolic engineering. However, conventional screening tools have several limitations regarding throughput, cost, and labor. Here, we used the fluid array platform to conduct high-throughput screening (HTS) that identified Escherichia coli 'TesA thioesterase mutants producing elevated yields of free fatty acids (FFAs) from a large (106) mutant library. A growth-based screening method using a TetA-RFP fusion sensing mechanism and a reporter-based screening method using high-level FFA producing mutants were employed to identify these mutants via HTS. The platform was able to cover >95% of the mutation library, and it screened target cells from many arrays of the fluid array platform so that a post-analysis could be conducted by gas chromatography. The 'TesA mutation of each isolated mutant showing improved FFA production in E. coli was characterized, and its enhanced FFA production capability was confirmed.

Mercury is one of the most common heavy metals and a major environmental pollutant that affects ecosystems. Since mercury and its compounds are toxic to humans, even at low concentrations, it is very important to monitor mercury contamination in water and foods. Although conventional mercury detection methods, including inductively coupled plasma mass spectrometry, atomic absorption spectroscopy, and gas chromatography-mass spectrometry, exhibit excellent sensitivity and accuracy, they require operation by an expert in a sophisticated and fully controlled laboratory environment. To overcome these limitations and realize point-of-care testing, many novel methods for direct sample analysis in the field have recently been developed by improving the speed and simplicity of detection. Commonly, these unconventional sensors rely on colorimetric, fluorescence, or electrochemical mechanisms to transduce signals from mercury. In the case of colorimetric and fluorescent sensors, benchtop methods have gradually evolved through technology convergence to give standalone platforms, such as paper-based assays and lab-on-a-chip systems, and portable measurement devices, such as smartphones. Electrochemical sensors that use screen-printed electrodes with carbon or metal nanomaterials or hybrid materials to improve sensitivity and stability also provide promising detection platforms. This review summarizes the current state of sensor platforms for the on-field detection of mercury with a focus on key features and recent developments. Furthermore, trends for next-generation mercury sensors are suggested based on a paradigm shift to the active integration of cutting-edge technologies, such as drones, systems based on artificial intelligence, machine learning, and three-dimensional printing, and high-quality smartphones.

The Influence of sintering temperature on the physical, electrochemical and sensing properties of α-Fe2O3-SnO2 nanocomposite sensing electrode for a mixed-potential type NOx sensor is investigated. The α-Fe2O3-SnO2 nanocomposite was synthesized by a solution combustion route and sintered at temperatures 900, 1000, 1100 and 1200 °C to form the sensing electrodes of a stabilized-zirconia based mixed-potential type NOx sensor. The influence of sintering temperatures on the physical properties was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and N2 adsorption-desorption isotherm measurements. The gas sensing measurements were conducted at an operating temperature of 650 °C. A systematic increase in the response/recovery times was observed with an increase in the sintering temperature from 900 to 1200 °C. An optimum microstructure with a low surface area and large pore size leading to high electrochemical reactions at the interface and low heterogenous gas-phase decomposition of NO2 resulted in the maximum response magnitude (ΔV) and sensitivity for the electrode sintered at 1000 °C. Furthermore, the effect of sintering temperature on the electrochemical activity of the sensing electrode and its co-relation with the sensing properties was studied by dc polarization curve measurement. Moreover, the microstructure, sensing response, sensitivity, dynamics and O2 conc. dependence of the presented mixed-potential type NOx sensor is critically dependent upon the sintering temperature of the sensing electrodes.

Background In mammals, UV radiation induces melanin synthesis in melanocyte for protecting their skin through the stimulation of α-melanocyte stimulating hormone (α-MSH) from keratinocytes. In this study, the inhibitory effects of dehydroglyasperin C (DGC), an useful component of Glycyrrhiza uralensis (G. uralensis), was investigated on melanogenesis induced by α-melanocyte stimulating hormone (α-MSH) and its mechanisms. Methods Melanogenesis suppression effect of DGC on α-MSH induced B16F1 melanoma cells. The cell viability was measured by MTT assay. Expression and phosphorylation of melanogeic protein were conducted using western blot. cAMP acceleration was measured by cAMP immunoassay kit. To investigate whitening mechanism, we used ERK inhibitor (PD98059). Results DGC decreased intra cellular tyrosinase (TYR) activity and expression of melanin synthesis related proteins (TYR and TRP-1) in a dose-dependent manner on α-MSH induced melanogenesis. In addition, DGC induced the downregulation of MITF (melanocyte-specific transcription factor) through suppression of cAMP-CREB pathway. Also, phosphorylation of extracellular signal regulated kinase (ERK) decreased MITF by DGC treatment. Conclusion Therefore, DGC could be used as a whitening ingredient in skin and clinical usage against hyperpigmentation.

Target analyte detection using whole-cell microbial biosensors can benefit from a microchemostat platform owing to the reduced reagent consumption, a finely controllable environment, and multi-parallel processing. However, the use of the previous microchemostat still has limitations for practical applications, e.g., its single-use design, long time requirements for cell and device preparation, low portability, slow and weak response signals, and the lack of ready-to-use in situ devices. In the present study, we developed a novel microchemostat platform that resolves these issues and enhances the performance of microbial biosensors via its abilities to actively control the cell population and to form a uniform culture environment using a nanoscale hydrodynamic film (NHF). The combination of the microchemostat platform and the microbial biosensors yielded fast and strong signals on demand in response to heavy metal ions (e.g., Pb2+). In addition, the platform enables the long-term on-chip storage of microbial biosensors for over 1 month, without deterioration of growth and detection ability. Lastly, we demonstrated that microbial biosensors can consecutively measure multiple samples by a regeneration process in which the microchemostat platform continuously subcultures the microbial biosensors until the complete recovery of their sensing capabilities. Thus, the microchemostat offers whole-cell microbial biosensors that are fast, ready-to-use, reusable, and storable. It also shows good potential for user-friendly, portable on-site environmental monitoring, particularly where expensive analytical tools and/or instruments for heavy metal ion detection are unavailable.

A compartmentalized microfluidic chamber array that offers not only separate cell culture environments but also independent control of the diffusion of small molecules provides an extremely useful platform for cell cultivations and versatile cellular assays. However, it is challenging to incorporate both cell compartmentalization and active diffusion control in real-time and precise manners. Here, we present a novel nanoscale hydrodynamic film (NHF) that is formed between a solid substrate and a polydimethylsiloxane (PDMS) surface. The thickness of the NHF can be adjusted by varying the pressure applied between them so that the mass transfer through the NHF can also be controlled. These novel phenomena are characterized and applied to develop a compartmentalized microchamber array with diffusion-tunable and solution-switchable chemostat-like versatile bacterial assays. The NHF-based compartmentalization technique is ideal for not only continuous bacterial cultivation by consistently refreshing various nutrient sources but also various diffusion-based microbial assays such as chemical induction of synthetically engineered bacterial cells and selective growth of a specific bacterial strain with respect to chemical environments. In addition, we show that tight compartmentalization protects cells in the chambers, while biofilm formation and nutrient contamination are eliminated by loading a lysis buffer, which typically hinders long-term continuous cultures and accurate microbial assays on a chip. Therefore, we ensure that the NHF-based compartmentalization platform proposed in this work will facilitate not only fundamental studies in microbiology but also various practical applications of microbes for production of valuable metabolites and byproducts in a high-throughput and highly efficient format.

A point-of-care testing chip was developed for the colorimetric detection of inorganic mercury ion (Hg2+). The disposable chip fabricated by three-dimensional printing technology contains DNAzymes produced by rolling circle amplification (RCA); a color change caused by the enzymatic reaction between DNAzymes and the peroxidase substrate 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) is measured using a portable spectrophotometer. In the “turn-off”-type RCA reaction, the annealing of the T(12) primer that initiates the RCA reaction is blocked by the interaction of thymine with Hg2+; thus, the amount of amplified DNAzymes causing a color change is decreased depending on Hg2+ concentration. The colorimetric signal is enhanced by amplifying double-repeat DNAzymes from a circular DNA template. The chip detected Hg2+ in tap drinking water samples with high sensitivity (lowest validated value: 3.6 μg/L) and showed better selectivity, precision, and reproducibility than conventional analysis instruments. This low-cost easy-to-use platform can reduce the risk of accidental Hg2+ poisoning.

Liquiritin and its aglycone, liquiritigenin are flavonoid found in licorice that show anti-oxidant and anti-aging properties. In this study, ethosomes loaded with hydrophobic liquiritigenin or liquiritin were prepared as a transdermal delivery system. The particle size, entrapment efficiency, and skin permeability of ethosomes were evaluated. Ethosome containing liquiritigenin was stable up to 2 mM and ethosome containing liquiritin was stable up to 0.75 mM concentration. The particle size of etho-somes containing 0.75 mM liquiritigenin and liquiritin was 143.85 and 158.90 nm, respectively and the entrapment efficiency was 47.51 and 54.61%, respectively. The entrapment efficiency was improved with increasing concentrations of drugs. Ethosomes loaded with liquiritigenin or liquiritin were superior in skin permeation ability compared to that of 20% ethanol solution and conventional liposomes. These results suggest that ethosomes containing 0.50 mM liquiritigenin or liquiritin are effective for the skin permeation and may be used as an antiaging and antioxidant ingredient in cosmetic formulation.

본 연구에서는 명월초 추출물의 메탄올 분획물과 아글리콘 분획물을 제조하였고, 이들에 대한 항산화 활성을 측정하였다. 항산화 활성 측정은 1,1-diphenyl-2-picrylhydrazil (DPPH) radical을 이용한 프리 라디칼 소거활성, 루미놀 발광법을 이용한 활성산소 소거활성(총 항산화능) 및 활성산소( $^1O_2$ 등)로 유도된 세포손상에 있어서 세포 보호 효과를 측정하였다. 명월초 추출물의 프리 라디칼 소거활성( $FSC_{50}$ )은 메탄올 분획이 $90.25{\mu}g/mL$ 이고, 당을 제거한 아글리콘 분획은 $81.38{\mu}g/mL$ 를 나타내었다. 총 항산화능( $OSC_{50}$ )은 메탄올 분획 $16.96{\mu}g/mL$ , 아글리콘 분획 $12.30{\mu}g/mL$ 로, 프리 라디칼 소거활성 및 활성산소 소거활성 모두 아글리콘 분획에서 큰 활성을 나타내었다. $^1O_2$ 로 유도된 사람 적혈구의 세포손상에 대한 보호 효과는 ${\tau}_{50}$ 값으로 확인하였다. $5{\mu}g/mL$ 농도에서 메탄올 분획 및 아글리콘 분획의 ${\tau}_{50}$ 이 각각 36.7 및 76.1 min으로, 비교 물질인 (+)- ${\alpha}$ -tocopherol (35.4 min)과 비교했을 때 아글리콘 분획이 약 2배 더 큰 세포 보호 효과를 나타내었다. 이러한 결과들은 명월초 추출물의 아글리콘 분획물이 항노화 관련 화장품에 있어서 항산화소재로서 응용가능성이 있음을 시사하였다. 【In this study, the methanol fraction and aglycone fraction were made from Gynura procumbens (G. procumbens) extracts and their antioxidative effects were investigated. The free radical scavenging activity (1,1-diphenyl-2-picrylhydrazyl, DPPH), total antioxidant capacity by luminol-dependent chemiluminescence assay, and the protective effects against reactive oxygen species (ROS) in erythrocytes were measured to evaluate the antioxidative activities of the extracts. Free radical scavenging activities ( $FSC_{50}$ ) of the methanol fraction and aglycone fraction were 90.25 and $81.38{\mu}g/mL$ , respectively. Total antioxidant capacities ( $OSC_{50}$ ) of the methanol fraction and aglycone fraction were 16.96 and $12.30{\mu}g/mL$ , respectively. The free radical scavenging activity and total antioxidant capacity of the aglycone fraction were greater than those of methanol fraction. The cellular protective effect on the $^1O_2$ -induced cellular damage of human erythrocytes was confirmed by ${\tau}_{50}$ value. The ${\tau}_{50}$ value of the methanol fraction and aglycone fraction were 36.7 min and 76.1 min, respectively in $5{\mu}g/mL$ , and the aglycone fraction showed about 2 times higher cellular protecive effect than (+)- ${\alpha}$ -tocopherol (35.4 min). These results indicate that the aglycone fraction of G. procumbens extracts has application possibility as antioxidant ingredient of cosmetic.】

In this study, Polygonum aviculare L. extract, which has superior antioxidative and cellular membrane protective activity, was loaded onto cell penetrating peptide (CPP) conjugated liposomes to enhance transdermal delivery. The physical characteristics of typical liposomes and CPP-conjugated liposomes containing P. aviculare extract were evaluated. The particle sizes of both liposomes were approximately 150 nm. Whereas the zeta potential of typical liposomes was -45 mV, that of CPP-conjugated liposomes was +42 mV. The loading efficiency of P. aviculare extract in both liposomes was calculated to be about 83%. Fluorescent-labeled liposomes were prepared to evaluate cellular uptake and skin permeation efficiency. Using flow cytometry, we found that CPP-conjugated liposomes improved cellular uptake of the fluorescent dye as compared with the typical liposomes. In addition, the skin permeation of CPP-conjugated liposomes was proved higher than that of typical liposomes by confocal laser scanning microscopy studies and Franz diffusion cell experiments. The improved cellular uptake and skin permeation of the CPP-conjugated liposomes were due to the cationic arginine-rich peptide. In vivo studies also determined that the CPP-conjugated liposomes were more effective in depigmentation and anti-wrinkle studies than typical liposomes. These results indicate that the CPP-conjugated liposomes could be effective for transdermal drug delivery of antioxidant and anti-aging therapeutics.

Reporter-gene-based microbial biosensors have high potential for detecting small molecules, including heavy metal ions (HMIs), in a sensitive and selective manner by involving low costs. However, the sensitivity and dynamic range of the sensing mechanism are largely limited by the conventional culture environment that relies on the batch-type addition of the small molecules in nutrients and the subsequent genetic induction of sensing microbes. Here, we describe a high-throughput, chemostat-like microfluidic platform that can continuously supply both nutrients and inducers (HMIs) using microfabricated ratchet structures and a mixing microchannel network. We found that the microfluidic platform not only allowed microbial biosensors to be highly concentrated in a detection microchamber array but also enabled them to continuously grow and control synthetic genetic circuits in response to heavy metals. We also demonstrated that the combination of the platform and microbial biosensors enhanced the sensitivity for detecting divalent lead and cadmium ions by approximately three orders of magnitude relative to conventional batch-type methods. Because the platform is portable and only requires small sample volumes and fluorescent detection, the chemostat-like microfluidic platform in conjunction with microbial biosensors could be widely utilized to facilitate the specific and sensitive detection of molecular analytes on a chip.

Nanowires (NWs) with a high surface-to-volume ratio are advantageous for bio- or chemical sensor applications with high sensitivity, high selectivity, rapid response, and low power consumption. However, NWs are typically fabricated by combining several nanofabrication and even microfabrication processes, resulting in drawbacks such as high fabrication cost, extensive labor, and long processing time. Here, we show a novel NW fabrication platform based on "crack-photolithography" to produce a micro-/nanofluidic channel network. Solutions were loaded along the microchannel, while chemical synthesis was performed in the nanoslit-like nanochannels for fabricating silver nanobelts (AgNBs). In addition, the NW/NB fabrication platform not only made it possible to produce AgNBs in a repeatable, high-throughput, and low-cost manner but also allowed the simultaneous synthesis and alignment of AgNBs on a chip, eliminating the need for special micro- and/or nanofabrication equipment and dramatically reducing the processing time, labor, and cost. Finally, we demonstrated that the AgNBs can be used as chemical sensors, either as prepared or when integrated in a flexible substrate, to detect target analytes such as hydrogen peroxide.

To evaluate dry eye symptoms, tear film function and ocular surface changes in patients with psoriasis.The Dry Eye Questionnaire and ophthalmic examination including the Schirmer test, tear break-up time, corneal fluorescein test, meibomian gland obstruction and conjunctival impression cytology were assessed in patients with chronic plaque psoriasis. Results were compared between 30 patients and 30 healthy controls.The rate of positive responses in the Dry Eye Questionnaire and staining of corneal fluorescein test were significantly higher in the patients (P = 0.030) than in the controls (P = 0.012). The tear break-up time in patients was significantly lower than in the controls (P0.001). However, there were no differences in the Schirmer test and meibomian gland function between the patients and controls. In the impression cytology analysis, more cell alteration and decreased goblet cell density were observed in the patients (P0.001) compared with those obtained from controls (P = 0.003).The dry eye symptom was more common in patients with psoriasis. In addition, the patients showed a higher tear film instability and significant degeneration on the ocular surface when compared with the normal controls.

Purpose: To evaluate the clinical features and surgical outcomes for primary rhegmatogenous retinal detachments (RDs) in patients with pseudophakia after phacoemulsification. Methods: The medical records of patients with pseudophakia after phacoemulsification and intraocular lens implantation who had undergone surgery for primary rhegmatogenous RDs with a minimum duration of follow-up of 12 months were reviewed retrospectively. Results: A total of 104 patients were enrolled in this study and 106 eyes were analyzed. Post-operative retinal attachment was achieved in 87 of the eyes (82.1%) and the final visual acuities (logarithm of the minimum angle of resolution) were improved to 0.65 ± 0.49 from the baseline measurement of 1.51 ± 1.14 (p < 0.001). Re-operations were performed in 24 of the eyes (22.6%) and there were no visible retinal breaks in 30 of the eyes (28.3%). The failure to identify a retinal break during surgery was associated with a lower rate of retinal reattachment, worse final visual acuity, and a higher rate of re-operation (p = 0.002, p = 0.02, and p = 0.002, respectively). The location of the identified retinal break was more common in the superotemporal quadrant than in the other quadrants. Conclusions: The inability to identify a retinal break during surgery was associated with a poor final outcome. Other factors were less important for the functional and anatomic success in patients with pseudophakic RDs.

Purpose: To compare the effect of an intravitreal injection of bevacizumab alone (IVB) or combined with triamcinolone (IVB/IVT) versus triamcinolone (IVT) in patients with diabetic macular edema (DME). Methods: In this randomized three-arm clinical trial, eligible eyes were assigned randomly to one of the three study arms: the IVB group, 2 injections of 1.25 mg of bevacizumab with 6-week intervals; the IVB/IVT group, 1.25 mg of IVB with 2 mg of IVT, and the IVT group, 2 mg of IVT. The clinical course of best-corrected visual acuity and central macular thickness by optical coherence tomography was monitored for up to 12 months after the initial injection. Results: One hundred eleven eyes of 105 patients with DME completed 12 months of follow-up. The IVB/IVT group and the IVT group showed better visual acuity and reduced central macular thickness at 6 weeks and 3 months, compared with the IVB group (p = 0.041, p = 0.02 at 6 weeks; p = 0.045, p = 0.043 at 3 months, respectively). However, no significant difference in visual acuity and central macular thickness was observed between the three groups at 12 months (p = 0.088, p = 0.132, respectively). The frequency of retreatment was lower in the IVB/IVT and IVT groups during the 12-month period (p < 0.001). No significant differences in visual acuity or central macular thickness were observed between the IVB/IVT and IVT groups during the follow-up. Conclusion: IVB/IVT and IVT showed more pronounced effects during the earlier postinjection period. However, levels of visual acuity or central macular thickness at 12 months were comparable in the three study groups. No beneficial effect of the combination injection was observed.

PURPOSE To evaluate the levels of aqueous humor cytokines in the eyes of patients with central serous chorioretinopathy (CSC) before an intravitreal injection of bevacizumab. METHODS In a prospective interventional trial, 20 eyes of 20 patients with symptomatic CSC of at least 3 months duration and 20 eyes of 20 patients with cataract as control were included. Eyes with CSC received a single intravitreal injection of bevacizumab (1.25 mg/0.05 mL). Aqueous humor samples were collected from patients and controls. Multiplex bead assays were used for measurement of cytokines, including vascular endothelial growth factor and platelet-derived growth factor. RESULTS Similar vascular endothelial growth factor levels and significantly decreased platelet-derived growth factor levels were measured in the aqueous humor of eyes from patients with CSC compared with controls (P = 0.172 and P = 0.004, respectively). There was a significant inverse correlation between the vascular endothelial growth factor and platelet-derived growth factor in patients (r = -0.555; P = 0.026). Interleukin 6, interleukin 8, and monocyte chemoattractant protein-1 were detectable, but not significantly different between the patients and controls. CONCLUSION The results of the current study suggest that platelet-derived growth factor contributes to the pathogenesis of CSC; however, the roles of vascular endothelial growth factor in CSC are unclear and warrant further investigation.

Purpose To evaluate spectral-domain optical coherence tomography (OCT) findings based on preferential hyperacuity perimeter (PHP) in patients after idiopathic epiretinal membrane surgery. Methods Forty eyes of 40 patients undergoing surgery for idiopathic epiretinal membrane were included in the study. The best-corrected visual acuity, PHP, Amsler grid test, and OCT were assessed 3 months after surgery. Results Patients were classified based on the defect of hyperacuity by PHP, as follows: hyperacuity defect (n = 18 eyes) and hyperacuity intact (n = 22 eyes). There was no difference in age, gender, duration of symptoms, and visual acuity. The average macular thickness and inner nuclear layer thickness in the hyperacuity defect group was thicker than the hyperacuity intact group (P = 0.041 and P = 0.045, respectively). A disrupted photoreceptor layer was more common in the hyperacuity defect group compared with the hyperacuity intact group (P = 0.001). Conclusion With regard to metamorphopsia, a hyperacuity defect after epiretinal membrane surgery was associated with inner nuclear layer edema and photoreceptor disarrangement.

We report a case involving bilateral posterior ischemic optic neuropathy with Behçet's disease in a 49-year-old woman. The patient presented because of abrupt visual disturbances. An ophthalmic examination, including fluorescein angiography, visual field testing, and visual-evoked potentials, was performed. Her visual acuity was 20/100 bilaterally and posterior ischemic optic neuropathy was suspected. She was treated with systemic methylprednisolone; however, disc pallor developed and the visual acuity remained 20/200 bilaterally. Optic neuropathy can be bilateral, affect both eyes simultaneously, and lead to severe visual loss despite high doses of systemic steroid treatment. Optic neuropathy in Behçet's disease is very rare. This case provides clinical insight into the neuro-ophthalmologic manifestations of Behçet's disease.

To describe the clinical implications of outer foveolar defects on optical coherence tomography (OCT) in eyes treated surgically for macular hole (MH).Retrospective observational case series.Ninety-six eyes of 93 subjects who had undergone surgery for the treatment of idiopathic MH were included. Clinical data, including OCT prior to and at follow-up visits ranging from 3 to 32 months after surgery, were analyzed. Incidence, risk factors, and clinical outcomes of outer foveolar defect were evaluated.Outer foveolar defects were noted on postoperative OCT in 44 of the 96 eyes (45.8%). The mean preoperative diameter of MH in the eyes (333.5 ± 126.3 μm) evidencing outer foveolar defects was significantly smaller than those that did not (504.2 ± 155.6 μm) (P.0001). The mean disappearance time of the defect was estimated to be 182 days after surgery. The mean postoperative visual acuity (logMAR) improved to 0.40 ± 0.26 from 0.58 ± 0.23 after the disappearance of outer foveolar defects.Outer foveolar defects were detected predominantly after surgery for small MHs. The defect decreases gradually in size and eventually disappears completely approximately 6 months after surgery.

Purpose: The purpose of this study was to determine aqueous vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) levels in patients with central serous chori-oretinopathy (CSC) before a single intravitreal bevacizumab injection. Methods: Twelve eyes with symptomatic CSC were included. Samples from patients with cataracts served as controls. The levels of VEGF and IL-8 concentrations were measured in aqueous humor and plasma by multiplex bead assays. Results: All patients with CSC showed an improvement in visual acuity and resolved neurosensory detachment after intravitreal bevacizumab injection. The aqueous humor levels of VEGF and IL-8 were not significantly increased in patients with CSC compared with the healthy control group (18.2 ± 24.8 vs. 35.3 ± 28.5 pg/mL, P > 0.05; 2.3 ± 0.4 vs. 2.8 ± 0.3 pg/mL, P > 0.05, respectively). The plasma levels of VEGF and IL-8 in patients with CSC were not different from those in the healthy control group. Conclusion: Vascular endothelial growth factor and IL-8 were not increased in the aqueous humor and plasma of patients with CSC. The effect of intravitreal bevacizumab injection as a treatment for CSC must be fully understood, and the true effect of anti-VEGF treatment in patients with CSC remains to be elucidated.

Aims To compare clinical outcomes for patients with central serous chorioretinopathy (CSC) undergoing either focal laser photocoagulation or photodynamic therapy (PDT). Methods 26 eyes of 26 patients with symptomatic CSC underwent focal laser photocoagulation or half-dose PDT, as appropriate. Best-corrected visual acuity, optical coherence tomography and multifocal electroretinography were assessed prospectively prior to treatment and at 1, 3 and 6 months after treatment. Results 12 eyes in the focal laser group and 14 eyes in the PDT group were evaluated. One month after PDT, all eyes, except one, showed complete absorption of subretinal fluid, whereas five eyes in the focal laser group showed residual subretinal fluid (p=0.022). Visual acuity and parameters of multifocal electroretinography improved from baseline at 1, 3 and 6 months after treatment, without any significant differences between the two groups. However, compared with those in the PDT group at 1 month after treatment, P1 latencies in the first annuli of the focal laser group were delayed (40.1±5.5 ms and 34.9±2.5 ms, respectively; p=0.047). Conclusions Compared with focal laser, half-dose PDT may facilitate earlier resolution of macular detachment and earlier recovery of central retinal function. However, at 3 months after treatment and thereafter, no difference in anatomical and functional recovery was noted between the two modalities of treatment.

Ji Won Lim, Joon Hee Cho, Ha Kyoung KimDepartment of Ophthalmology, Hallym University Sacred Heart Hospital, Chuncheon, Republic of KoreaAbstract: The aim of the current study was to evaluate macular function before and after surgery for idiopathic epiretinal membranes with internal limiting membrane (ILM) peeling by means of multifocal electroretinography (ERG). Eighteen eyes of 18 patients who underwent vitrectomy with ILM removal were included. Best corrected visual acuity, optical coherence tomography (OCT), and multifocal electroretinography were assessed prior to surgery, and 3 and 12 months after surgery. All surgical samples were obtained and confirmed inclusion of an ILM by electron microscopy. Visual acuity and the central foveal thickness by OCT improved significantly 3 months postoperatively, with gradual recovery by 12 months. Preoperatively, only the P1 amplitude in rings 1 and 2 were decreased compared with the normal fellow eyes (P < 0.01). Three and 12 months after surgery, the P1 amplitude in rings 1 and 2 were decreased compared with the preoperative P1 amplitudes, but without significance. The photoreceptor status by OCT was related to the N1 amplitude before and after surgery. Although visual acuity and macular edema were improved after surgery, macular function, as indicated by multifocal ERG, had limited recovery at 12 months.Keywords: epiretinal membrane, macular function, multifocal electroretinography

Purpose: To investigate the clinical features of pegylated-interferon (PEG-IFN)-associated retinopathy in chronic hepatitis patients. Methods: We examined a consecutive case series of 46 patients who were treated with PEG-IFN for chronic hepatitis C or B between October 2007 and September 2008. All patients underwent regular ophthalmologic examinations every 3 weeks during the 6 months after treatment. Results: Ten of the 46 patients (21.73%) developed retinal abnormalities. PEG-IFN-associated retinopathy occurred a mean of 7.25 ± 10.28 weeks after treatment and manifested itself as cotton wool spots and retinal hemorrhages. All patients, except for 1 with a retinal vein occlusion, recovered without cessation of treatment. Conclusions: PEG-IFN-associated retinopathy in chronic hepatitis patients was reversible, and patients recovered without visual complications; however, 1 patient did present with an irreversible visual impairment. This type of retinopathy is usually asymptomatic, and clinicians should closely observe patients for 3 months after treatment.

Multiple copies of a cadC homolog encoding a heavy metal-responsive transcription factor were found in the genome of a bacterium isolated from ocean sediment, and the heavy metal responses of the encoded proteins were characterized using a fluorescence reporter assay. Each CadC regulator exhibited distinct specificity in response to heavy metal ions, indicating their potential use as modular heavy metal biosensors. Next, we constructed CadC-controlled T7 RNA transcription systems for intracellular signal amplification, i.e., higher sensitivity. Flow cytometry revealed that cadmium and lead ions could be recognized specifically by CadC-T7 biosensors, which could be combined with a microfluidic platform to generate heavy metal biosensor devices with increased sensitivity. Our results demonstrate the successful development of synthetic CadC-T7 genetic circuitry for use in improved heavy metal biosensor microfluidic devices.

Multivariate analysis was conducted to analyze the relationship between air pollutants and meteorological variables measured in Seoul from January 1 to December 31, 1999. The first principal component showed the contrast effect between O3 and the other pollutants. The second principal component showed the contrast effect between CO, SO2, NO2, and O3, PM10, TSP. Based on the cluster analysis, three clusters represented different air pollution levels, seasonal characteristics of air pollutants, and meteorological conditions. Discriminant analysis with Air Environment Index (AEI) was carried out to develop an air pollution index function.

Partial electronic conductivity and total conductivity of Zr0.84Y0.16O1.92 and Ce0.9Gd0.1O1.95 have been measured by Hebb-Wagner polarization method and D.C. 4-probe conductivity measurements, respectively as a function of temperature and oxygen partial pressure. (600 ≤ temp/˚C ≤ 900, 10-18 ≤ PO 2/atm ≤ 0.21) Theoretical current-voltage characteristics and power density were calculated by integrating partial conductivities of charge carriers under various DC bias condition at fixed oxygen chemical potential gradient at both sides of the electrolyte (YSZ side: PO 2=10-22 GDC side: PO 2=0.21). The spatial distribution of oxygen partial pressure across the bilayer electrolyte with various thickness ratio was calculated based on Choudhury and Patterson’s model by considering zero electrode polarization. From the spatial distribution, oxygen partial pressures of interface were calculated with various operating condition. Interfacial oxygen chemical potential with various thickness ratio (YSZ/GDC) shows strong dependence upon cell operating potential.

To evaluate the efficacy of intravitreal bevacizumab injection in the treatment of central serous chorioretinopathy (CSC). In a prospective interventional case series, 40 eyes of 40 patients with idiopathic CSC at least 3 months in duration were included. Patients were treated with once or twice intravitreal bevacizumab injections initially and completed at least 12 months follow-up. Main outcomes measures were the resolution of neurosensory detachment, best-corrected visual acuity, and findings on fluorescein and indocyanine green angiography. Thirty-three of 40 eyes (82.5%) showed complete absence of subretinal fluid at the macula within 3 months following initial intravitreal bevacizumab injection. Eyes exhibiting resolution of subretinal fluid revealed improvement in fluorescein and indocyanine green angiographic findings. The rate of intense hyperfluorescence on indocyanine green angiography was higher in eyes exhibiting resolution of subretinal fluid than eyes exhibiting incomplete absorption of subretinal fluid after intravitreal bevacizumab (72.7 and 28.5%, respectively, p = 0.039). Intravitreal bevacizumab injections generally resulted in anatomic improvement for CSC and may constitute a therapeutic option in CSC. The effect after intravitreal bevacizumab injection for CSC might be related to the hyperfluorescence on indocyanine green angiography.

Purpose: My aim was to evaluate the effect of intravitreal bevacizumab and to determine the concentrations of inflammatory cytokines in patients with macular edema due to branch retinal vein occlusion (BRVO), according to the site of the occlusion. Methods: In a prospective interventional case series, 46 eyes of patients with macular edema due to major (n = 30) or macular BRVO (n = 16) were included. The patients were treated primarily with intravitreal bevacizumab (1.25 mg/0.05 ml) and completed 12 months of follow-up. Reinjections were performed if optical coherence tomography showed persistent or recurrent macular edema. Aqueous humor samples were collected at the time of initial intravitreal injection. Multiplex bead assays were used for the measurement of cytokines. Results: The visual acuity and central macular thickness were improved significantly in patients with major and macular BRVO at 12 months. During 12 months, the eyes with major BRVO received a mean of 3.8 intravitreal injections, whereas those with macular BRVO received a mean of 1.9 intravitreal injections (p = 0.009). Significantly increased concentrations of IL-6, IL-8 and MCP-1 were observed in the aqueous humor of BRVO patients compared with control samples. Higher concentrations of IL-6, VEGF, PDGF-AA and MCP-1 were measured in the aqueous humor of patients with major BRVO compared with macular BRVO at baseline (p < 0.05). Conclusion: Intravitreal bevacizumab was similarly effective for improving macular edema in patients with major and macular BRVO. However, macular BRVO required fewer injections and had lower cytokine levels in the aqueous humor than major BRVO.