• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.102-110
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• 2018

A bacterial strain capable of metabolizing myo-inositol (MI) and converting to other substances was isolated from soil of orchard. The isolate, named YB-46, was grown on minimal medium supplemented with MI as the sole carbon source and was presumed to belonging to genus Enterobacter according to the 16S rDNA sequence. Escherichia coli transformant converting MI into unknown metabolites was selected from a metagenomic library prepared with fosmid pCC1FOS vector. Plasmid was isolated from the transformant, and the inserted gene was partially sequenced. From the nucleotide sequence, an iolG gene was identified to encode myo-inositol dehydrogenase (IolG) consisting of 336 amino residues. The IolG showed amino acid sequence similarity of about 50% with IolG of Enterobacter aerogenes and Bacillus subtilis. The His-tagged IolG (HtIolG) fused with hexahistidine at C-terminus was produced and purified from cell extract of recombinant E. coli. The purified HtIolG showed maximal activity at $45^{\circ}C$ and pH 10.5 with the highest activity for MI and D-glucose, and more than 90% of maximal activity for D-chiro-inositol, D-mannitol and D-xylose. $K_m$ and $V_{max}$ values of the HtIolG for MI were 1.83 mM and $0.724{\mu}mol/min/mg$ under the optimal reaction condition, respectively. The activity of HtIolG was increased 1.7 folds by $Zn^{2+}$, but was significantly inhibited by $Co^{2+}$ and SDS.

• Medical Lasers
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• v.9 no.1
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• pp.44-50
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• 2020

Background and Objectives To evaluate the rotational stability of AcrySof toric intraocular lenses (IOL) by considering lapse of postoperative time and influence of capsulorhexis contraction. Materials and Methods A prospective, masked, single center study was conducted on 19 patients who had undergone microcoaxial cataract surgery and AcrySof toric IOL implantation. Slit-lamp retroillumination photographs of anterior segments were obtained from all patients after 1 week, 1 month and 3 months post-surgery. The degree of alteration of the postoperative IOL axis alignment and the amount of anterior capsular shrinkage were analyzed using Adobe Photoshop software. Results The mean degree of toric IOL axis misalignment was 2.18 (±20.2) degrees at 3 months follow-up. Quadrant analysis of the capsulorhexis aperture area at 1 week and 1 month post-operative, showed counterclockwise IOL rotation when the capsule contraction was dominant in the haptic part as well as clockwise rotation when dominant in the non-haptic part (p = 0.015). Conclusion The direction and degree of AcrySof toric IOL rotation differed throughout the follow-up period. Since most misalignments were found on the first post-operative day, physicians should try to minimize peri-operative risk factors that influence IOL rotation. There was also a correlation between the part of anterior capsule contraction and the direction of IOL rotation.

• Journal of Korean Medical Science
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• v.33 no.44
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• pp.275.1-275.15
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• 2018

Background: We compared the efficacy between trifocal and bifocal diffractive intraocular lens (IOL) implantation. Methods: Through PubMed, MEDLINE, EMBASE, and CENTRAL, we searched potentially relevant articles published from 1990 to 2018. Defocus curves, visual acuities (VAs) were measured as primary outcomes. Spectacle dependence, postoperative refraction, contrast sensitivity (CS), glare, and higher-order aberrations (HOAs) were measured as secondary outcomes. Effects were pooled using random-effects method. Results: We included 11 clinical trials, with a total of 787 eyes (395 subjects). The trifocal IOL group showed better binocular distance VA corrected with defocus levels of -0.5, -1.0, -1.5, and -2.5 diopter than the bifocal IOL group (All $P{\leq}0.004$). The trifocal IOL group showed better monocular uncorrected distance and intermediate VAs (mean difference [MD], -0.04 logarithm of the minimum angle of resolution [logMAR]; 95% confidence interval [CI], -0.07, -0.01; P = 0.006 and MD, -0.07 logMAR; 95% CI, -0.13, -0.01; P = 0.03, respectively). Postoperative refraction, glare, CS, and HOAs were not significantly different from each other. Conclusion: The overall findings indicate that trifocal diffractive IOL implantation is better than the bifocal diffractive IOL in intermediate VA, and provides similar or better in distance and near VAs without any major deterioration in the visual quality.

• Journal of Korean Biological Nursing Science
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• v.21 no.1
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• pp.12-21
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• 2019

Purpose: The purpose of this study was to review previous literature with an aim to explore the sleep disturbance level after a patient undergoes cataract surgery using an integrative review. Methods: We used the key words, 'cataract surgery', 'sleep', and 'intraocular lens' to find peer-reviewed publications in seven databases. Among 450 searched articles, eight articles were selected after exclusion of articles that did not meet the criteria. Results: Five of the articles submitted that subjective sleep quality of the patients with blue-filtering intraocular lens (BF-IOL) implant improved as compared to that before surgery. The change of saliva melatonin concentration after BF-IOL implant did not coincide in two of the articles. Two of the articles reported an increased level of intrinsically photosensitive retinal ganglion cells response after BF-IOL implantation. Conclusion: The published studies stated that BF-IOL implant did not have any negative impact on quality of sleep among cataract patients suffering with poor sleep. Rregardless of intraocular lens type, cataract surgery may increase photoreception of intrinsically photosensitive retinal ganglion cells one year after surgery although the mechanism was not clear. It is necessary to identify various factors influencing the quality of sleep such as gender and activities among cataract patients with BF-IOL implant in the future.

• Macromolecular Research
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• v.16 no.7
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• pp.614-619
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• 2008

Copolymers of phenyl alkyl acrylates/methacrylates are used clinically as soft materials for the foldable intraocular lens (IOL) to treat cataracts. In this study, copolymers of 2-phenylethyl acrylate (PEA) and 2-phenylethyl methacrylate (PEMA) of various compositions were prepared using free radical polymerization in solution. The composition of the copolymers was determined by $^1H$-NMR analysis. The reactivity ratios of the monomers were calculated using the conventional Fineman-Ross or Kelen-Tudos method. The reactivity ratio of PEA ($r_1$) and PEMA ($r_2$) were estimated to be 0.280 and 2.085 using the Kelen-Tudos method, respectively. These values suggest that PEMA is more reactive in copolymerization than PEA, and the copolymers will have a higher content of PEMA units. The glass transition temperature ($T_g$) of the copolymers increased with increasing PEMA content. The molecular weight and polydispersity indices ($M_w/M_n$) of the polymers were determined by GPC. Overall, these results are expected to be quite useful in applications to foldable soft IOL materials.

• Journal of the korean veterinary medical association
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• v.40 no.10
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• pp.913-924
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• 2004

• Journal of Power Electronics
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• v.14 no.5
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• pp.989-999
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• 2014

High-performance Current Source Inverter (CSI)-fed, variable speed alternating current drives are prepared for various industrial applications. CSI-fed Induction Motor (IM) drives are managed by using different control methods. Noteworthy methods include scalar Control (V/f), Input-Output Linearization (IOL) control, Field-Oriented Control (FOC), and Direct Torque Control (DTC). The objective of this work is to compare the dynamic performance of the aforementioned drive control methods for CSI-fed IM drives. The dynamic performance results of the proposed drives are individually analyzed through sensitivity tests. The tests selected for the comparison are step changes in the reference speed and torque of the motor drive. The operation and performance of different vector control methods are verified through simulations with MATLAB/Simulink and experimental results.

• Journal of Preventive Medicine and Public Health
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• v.27 no.4 s.48
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• pp.807-814
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• 1994

This study is to find out changes in medical practice at a university hospital before and after covering intraocular lens (IOL) from the health insurance benefit. The coverage started on March 1, 1993 and a total of 596 cases who were discharged from July 1 to December 31, 1992 and 580 cases who were discharged from July 1 to December 31, 1993 were analyzed. Since the standard reimbursement scheme was changed from March 1, 1993, the charges for 1992 were transformed into 1993 scheme. Major findings are as follows: Average length of stay was statistically significantly decreased from 8.24 days in 1992 to 6.86 days in 1993. Charges except IOL has been statistically significantly decreased from 501,000 Won in 1992 to 444,000 Won in 1993. Charges for drugs and injection have been reduced. However, charge per day for them was not much different. This is due to decrease in length of stay. Charges for laboratory tests and radiologic examination were quite the same. Charges which are not covered by the insurance remained the same. The revenue of the hospital was reduced as expected. However, the hospital reduced the length of stay and increase the turnover rate In order to compensate the potential loss of revenue due to the difference of reimbursement between the out-of-pocket expense and the insurance coverage. By introducing the IOL benefit in the insurance, the insured pays less, hospital generates more revenue through shortening the hospital stay, and the total medical care cost becomes less nationwidely.

• Korean Journal of Ophthalmology
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• v.32 no.6
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• pp.497-505
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• 2018

Purpose: To evaluate and compare published methods of calculating intraocular lens (IOL) power following myopic laser refractive surgery. Methods: We performed a retrospective review of the medical records of 69 patients (69 eyes) who had undergone myopic laser refractive surgery previously and subsequently underwent cataract surgery at Samsung Medical Center in Seoul, South Korea from January 2010 to June 2016. None of the patients had pre-refractive surgery biometric data available. The Haigis-L, Shammas, Barrett True-K (no history), Wang-Koch-Maloney, Scheimpflug total corneal refractive power (TCRP) 3 and 4 mm (SRK-T and Haigis), Scheimpflug true net power, and Scheimpflug true refractive power (TRP) 3 mm, 4 mm, and 5 mm (SRK-T and Haigis) methods were employed. IOL power required for target refraction was back-calculated using stable post-cataract surgery manifest refraction, and implanted IOL power and formula accuracy were subsequently compared among calculation methods. Results: Haigis-L, Shammas, Barrett True-K (no history), Wang-Koch-Maloney, Scheimpflug TCRP 4 mm (Haigis), Scheimpflug true net power 4 mm (Haigis), and Scheimpflug TRP 4 mm (Haigis) formulae showed high predictability, with mean arithmetic prediction errors and standard deviations of $-0.25{\pm}0.59$, $-0.05{\pm}1.19$, $0.00{\pm}0.88$, $-0.26{\pm}1.17$, $0.00{\pm}1.09$, $-0.71{\pm}1.20$, and $0.03{\pm}1.25$ diopters, respectively. Conclusions: Visual outcomes within 1.0 diopter of target refraction were achieved in 85% of eyes using the calculation methods listed above. Haigis-L, Barrett True-K (no history), and Scheimpflug TCRP 4 mm (Haigis) and TRP 4 mm (Haigis) methods showed comparably low prediction errors, despite the absence of historical patient information.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.103-104
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• 2010