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Biomedical subjects

Bong-Hyun Kim

Publications and source records attributed to Bong-Hyun Kim.

2 recordsLinked to original sources

Lightless cataract surgery using a near-infrared operating microscope.

PURPOSE: To describe the near-infrared (NIR) operating microscopy (NIOM) system using the NIR wavelength as the illumination source and to evaluate the feasibility of this system for lightless cataract surgery. SETTING: HenAm Kim Eye Center, Haenam-Gun, South Korea. METHODS: In this noncomparative interventional case series, cataract surgery was performed in 4 patients with bilateral cataract using the NIOM system in 1 eye and conventional microscopy in the fellow eye. The primary components of the system include an optical filter, a stereoscopic camera, head-mounted displays, and a recording system. This system uses invisible NIR (wavelength 850 to 1300 nm) illumination to facilitate cataract surgery without light. The differences between the NIOM system and conventional microscopy during cataract surgery were evaluated. RESULTS: The NIOM system provided excellent 3-dimensional viewing in real time. The image resolution was sufficient while performing all steps of cataract surgery. Immediately postoperatively and at 10 and 30 minutes and 1 hour, the visual acuity was better in the 4 eyes in which the NIOM system was used than in the 4 eyes in which conventional microscopy was used. However, using the NIOM system required good surgical skill. CONCLUSIONS: Lightless cataract surgery using the NIOM system seems useful for obtaining good visual acuity immediately postoperatively. The system may also reduce the incidence of light-induced retinal toxicity and the need for mydriatic administration and be a good educational tool.

Aged↗

COG4849 is a novel family of nucleotidyltransferases.

Only a minority of currently known protein families is characterized structurally. This makes homology-based structure modeling an essential instrument that can be viewed as the first approximation to experimental determination of protein structure. Using sequence similarity searches, we detected a distant similarity between a family of uncharacterized hypothetical proteins, COG4849, and the family of tRNA nucleotidyltransferases. The suggested remote homology between the N-terminal domain of COG4849 and the catalytic domain of tRNA nucleotidyltransferase was further supported by comparison of sequence profiles, methods for fold recognition and structure modeling. The combined multiple alignment of the two families reveals shared conservation of functionally important motifs and suggests the similarity in catalytic mechanisms of the performed reactions. Our results suggest that (i) the N-terminal domain of proteins from COG4849 shares structural similarity with the catalytic domain of tRNA nucleotidyltransferase, and (ii) this domain catalyzes the nucleotidyl transfer reaction involving two metal ions.

Bacterial Proteins↗