Monitoring of Genetically Modified Bean Sprouts at Traditional Markets in Seoul and a Survey of Perception of Traditional Market Merchants and High School Students on Genetically Modified Organisms / 대한지역사회영양학회지

The purpose of this study is to monitor genetically modified bean sprouts at traditional markets in Seoul and to investigate perception of traditional market merchants and high school students on genetically modified organisms (GMOs). We analyzed 30 bean sprouts that were selected at 11 traditional markets in Seoul using the method of polymerase chain reaction (PCR). Also, we compared perception of GMOs between merchants (n = 30) and students (n = 126). Knowledge test about GMOs was performed by students. The result of PCR, 16.7% of bean sprouts were confirmed as GM bean sprouts (n = 5). Students had significantly more exposure to information about GMOs than merchants (p < 0.05). Major information sources about GMOs were from mass media (television, newspaper and radio). About half of subjects were not aware that they eat GMOs and GMOs are sold to consumers. Only 17.3% of subjects had constant eating intent for GMOs after perceiving foods that he/she usually eats are GMOs. 51.3% of subjects had willingness to purchase GMOs if GMOs have same quality and lower cost than natural foods. 37.2% of subjects thought that GMOs would be harmful to humans. Students had more positive perception of GMOs' side effects than merchants (p < 0.01). There was no merchant who knew labeling of GMOs. 19.1% of students knew labeling of GMOs. Students' mean percentage of correct answers of six questions about GMOs was 45.2%. Therefore, providing adequate information about GMOs is needed for consumer's choice whether to purchase GMOs or not.

Intravitreal Triamcinolone Versus Bevacizumab for Treatment of Diabetic Macular Edema

PURPOSE: To compare central macular thickness (CMT) and visual acuity outcomes after intravitreal injection of triamcinolone acetonide or bevacizumab for the treatment of diabetic macular edema (DME). METHODS: Fifty-one patients were randomly choosen to receive an intravitreal injection of either triamcinolone acetonide or bevacizumab. Patients were retrospectively reviewed, and 28 of 51 received an intravitreal injection of triamcinolone acetonide while the remaining 23 received bevacizumab injection. All patients underwent Snellen visual acuity testing, optical coherence tomography imaging and ophthalmoscopic examination at baseline and at four weeks following the injection. RESULTS: In the triamcinolone group, CMT decreased from 656.71+/-194.37 micrometer at baseline to 312.46+/-102.14 micrometer at the four-week follow-up visit, while in the bevacizumab group, CMT decreased from 582.17+/-151.02 micrometer at baseline to 453.09+/-172.39 micrometer at the follow-up (p<0.05). The LogMAR best-corrected visual acuity converted from the Snellen visual acuity significantly improved in the triamcinolone group (from 0.89+/-0.38 to 0.67+/-0.33) compared to the bevacizumab group (from 0.79+/-0.31 to 0.70+/-0.34) [p<0.05]. CONCLUSIONS: Intravitreal injection of triamcinolone may offer advantages over bevacizumab in the short-term management of DME, specifically with respect to improvement in CMT and visual acuity.

Intravitreal Triamcinolone Versus Bevacizumab for Treatment of Diabetic Macular Edema

PURPOSE: To compare central macular thickness (CMT) and visual acuity outcomes after intravitreal injection of triamcinolone acetonide or bevacizumab for the treatment of diabetic macular edema (DME). METHODS: Fifty-one patients were randomly choosen to receive an intravitreal injection of either triamcinolone acetonide or bevacizumab. Patients were retrospectively reviewed, and 28 of 51 received an intravitreal injection of triamcinolone acetonide while the remaining 23 received bevacizumab injection. All patients underwent Snellen visual acuity testing, optical coherence tomography imaging and ophthalmoscopic examination at baseline and at four weeks following the injection. RESULTS: In the triamcinolone group, CMT decreased from 656.71+/-194.37 micrometer at baseline to 312.46+/-102.14 micrometer at the four-week follow-up visit, while in the bevacizumab group, CMT decreased from 582.17+/-151.02 micrometer at baseline to 453.09+/-172.39 micrometer at the follow-up (p<0.05). The LogMAR best-corrected visual acuity converted from the Snellen visual acuity significantly improved in the triamcinolone group (from 0.89+/-0.38 to 0.67+/-0.33) compared to the bevacizumab group (from 0.79+/-0.31 to 0.70+/-0.34) [p<0.05]. CONCLUSIONS: Intravitreal injection of triamcinolone may offer advantages over bevacizumab in the short-term management of DME, specifically with respect to improvement in CMT and visual acuity.

Ocular Concentration after Subtenon and Intravitreal Injection of Triamcinolone Acetonide in Rabbits

PURPOSE: To improve our understanding of the pharmacokinetics of triamcinolone acetonide (TA) and TA concentration in ocular tissue, TA concentration was measured in ocular tissue after intravitreal and subtenon injection. METHODS: Fifteen rabbit eyes underwent subtenon TA injection (40 mg/1 ml), and another 15 rabbit eyes underwent intravitreal TA (4 mg/0.1 ml) injection. All eyes were enucleated at 1, 2, 4, 8, and 12 weeks after subtenon and intravitreal injection, and TA concentration in the aqueous and vitreous humor and the retina-choroid were measured by high performance liquid chromatography (HPLC). RESULTS: In cases of subtenon's TA injection, TA concentrations were 0 ng/ml, 136.7 ng/ml, 178.7 ng/ml, 0 ng/ml, and 0 ng/ml in the aqueous humor; 99.1 ng/ml, 125.7 ng/ml, 726.8 ng/ml, 0 ng/ml, and 0 ng/ml in the vitreous humor; 72.7 ng/ml, 304.6 ng/ml, 459.0 ng/ml, 0 ng/ml, and 0 ng/ml in the retina-choroid after 1, 2, 4, 8, and 12 weeks, respectively. In cases of intravitreal TA injection, the measured values were 0 ng/ml, 0 ng/ml, 0 ng/ml, 654.1 ng/ml, and 0 ng/ml in the aqueous humor; 28152.2 ng/ml, 13646.4 ng/ml, 11388.8 ng/ml, 10297.2 ng/ml, and 183.0 ng/ml in the vitreous humor; and 0 ng/ml, 27.9 ng/ml, 108.3 ng/ml, 0 ng/ml, and 0 ng/ml in the retina-choroid at each time point. CONCLUSIONS: Intravitreal TA injection may be more effective for drug delivery than subtenon TA injection, but subtenon TA injection seems to be an effective and safe technique.

The Development of Biodegradable Intrascleral Implant for Slow Releasing of Triamcinolone Acetonide

PURPOSE: In order to treat inflammatory and proliferative disorders of the posterior segment of the eye, the authors evaluated the use of a biodegradable intrascleral implant for slow release of triamcinolone acetonide (TA). METHODS: The intrascleral implant (1 mm thick and 3 mm in diameter) was made of alginic acid and PLA (poly (D, L-lactide)) containing 4 mg of TA. In vitro release of TA was evaluated by HPLC. To evaluate in vivo release of TA, the implant was placed into a scleral pocket in 18 rabbit eyes and the concentrations of TA in the aqueous humor, vitreous, and retina-choroid-sclera were measured by HPLC at 1, 2, 4, 8, and 12 weeks after implantation. The toxicity and biocompatibility of the implant were evaluated by slit lamp examination, IOP, electroretinogram, and light microscopy. RESULTS: In vitro study demonstrated that the implant released TA in controlled manner for at least 8 months. The TA detected in the vitreous after 8 to 12 weeks and was not detected in retina-choroid-sclera at 8 weeks after implantation. The TA was not detected in aqueous humor. No significant toxicity to the retina was observed. CONCLUSIONS: These results suggest that the intrascleral implant of TA could be a promising system for the delivery of steroids to the posterior segment of eye in cases of inflammatory or proliferative disorders of posterior segment.

Artificial Retina Mimbrane Assembly Utilzing Intelligent Materials: Biocompatibility and Electorphysiologic Features

In recent studies there have been various attempts at replacing a damaged retina with an artificial one. This paper outlines the assembly of an artificial retina membrane by incorporating a photorective protein bacteriorhodopsin into an electrochemically syntheszed conducting polymer polypyrrole. An electrophysiologic test was conducted to evaluate the photoresponsiveness of the bacteriorhodopsin and rabbit eyes were used to examine the biocompatibility of the artificial retina. The electrophysiologic test analyzed both wave forms and amplitudes obtained by photostimulating the artificial retina membrane with various light intensites(0.2, 2, 20J). In the biocompatibility test, the artificial membrane was inserted into the anterior chambers(4 eyes) and vitreous cavities(8 eyes) of rabbits. The condition of the eyes was then observed for one month. At the end of the first moonth, the eyes were enucleated and a histological examination was carried out. The electrophysiologic study displayed negative reflection waves, which are characteristic in rhodpsin, and their amplitudes showed a correspondign increase with stronger light intensities. The results of the biocompatibility test demonstrated that inflammatory reactions were not prominent in either the anterior chambers or the vitreous cavities during the first month and the histological examinations revealed no specific findings. In conclusion, a membrane assembled utilizing an electroactive polymer and a phocial retina.

Choroidal Folds Secondary to an Orbital Tumor

Folding of the choroid, Bruchs membrane, and the overlying retina may occur in a variety of ocular and orbital diseases and after certain surgical procedures. A 34-year-old man experienced the decreased visual acuity and the protrusion and displacement in the right eye for at least 4 years. The protrusion of the patient was 13mm in the right eye and 6mm in the left eye with the aid of Hertels exophthalmometer. The right eye appeared downward deviation about 15 prism. The tumor located outside the muscle cone in the computed tomography and ultrasonography seemed to make the large choroidal folds involving the macula region. The retinal pigment epithelial atrophy was noted along long-standing choroidal folds. The tumor was removed by the lateral orbitotomy. The size of tumor was 20 x 15x 10mm. The postoperative protrusion was 6mm in the both eye. After removal of tumor, changes in the corneal refraction, visual acuity, and choroidal folds with the retinal pigment epithelial atrophy did not occur in comparison with the preoperative state.

Macroaneurysms of Retinal Arteries

Two patients with spontaneous intraretinal or subretinal hemorrhages were found, on evaluation by fluorescein angiography, to have macroaneurysms involving the major retinal arteries. Both patients were male in their seventies. One patient had a history of systemic hypertension. In the other patient, hypertension was discovered at the time of consultation. With absorption of the hemorrhage and the macular star, two patients experienced appreciable improvement in vision. Laser thrapy was not applied to both patients. The aneurysms diminished in size after 6 to 8 months as a result of fibrous changes within the arterial walls.

The Standard Electroretinogram in Non-diabetic Branch Retinal Vein Occlusion

We carried out five common electroretinographies according to the recommendation by the International Society of Clinical Electrophysiology of Vision in the eyes of 40 non-diabetic brach retinal vein occulusion. The clear media, no previous history of photocoagulation and no evidence of neovascularization of the retina and/or iris were criteria for inclusion in this study. The data were compared with those of fellow eyes, expecting that this procedure may provide a new feature that could have some clinical significance. The reduction of the summed amplitude of oscillatory potentials, and the timing delay of the cone response b-wave and 30Hz flicker responses were of most frequent occurrence. hence, the reduction of the summed amplitude of oscillatory potentials and the timing delay of the cone response b-wave and 30Hz flicker responses may be valuable indicators. These abnormalities represent overall inner retinal dysfunction. The cone response b-wave timing was more frequently affected than that of the maximal combined response b-wave. This fact may reflect that an ischemic lesion is located in the vicinity of the posterior pole of the fundus.

The Calculation of the Electroretinographic Power

To promote the electrophysiologic diagnostic efficiency, the program for calculation of the total power in the frequency domain and of the area in the time domain of the electroretinogram was designed. The total power is calculated by integration of the squared power spectrum obtained by Fourier transform (Parseval theorem) in the time domain. The dominant power is the power of the dominant frequency in power spectrum and is calculated by integration of the squared peak area spectrum. The sectional inegration of the squared power spectrum can be established by manual input. The inplemented software also has the functions that calculate the summed amplitud and area of the oscillatory potentials in the time domain. And it performs each functions by selection of pop-up menu with mouse to use conveniently under graphic interface, compatible with UTAS-E2000 system.