• Molecules and Cells
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• v.46 no.9
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• pp.538-544
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• 2023

The formation of uniform vitreous ice is a crucial step in the preparation of samples for cryogenic electron microscopy (cryo-EM). Despite the rapid technological progress in EM, controlling the thickness of vitreous ice on sample grids with reproducibility remains a major obstacle to obtaining high-quality data in cryo-EM imaging. The commonly employed classical blotting process faces the problem of excess water that cannot be absorbed by the filter paper, resulting in the formation of thick and heterogeneous ice. In this study, we propose a novel approach that combines the recently developed nanowire self-wicking technique with the classical blotting method to effectively control the thickness and homogeneity of vitrified ice. With simple procedures, we generated a copper oxide spike (COS) grid by inducing COSs on commercially available copper grids, which can effectively remove excess water during the blotting procedure without damaging the holey carbon membrane. The ice thickness could be controlled with good reproducibility compared to non-oxidized grids. Incorporated into other EM techniques, our new modification method is an effective option for obtaining high-quality data during cryo-EM imaging.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.2
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• pp.119-126
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• 2003

Objective: This study was carried out to compare the clinical outcomes of intracytoplasmic sperm injection (ICSI) in patients with obstructive azoospermia according to sperm retrieval site and technique; microsurgical epididymal sperm aspiration (MESA), percutaneous epididymal sperm aspiration (PESA), testicular sperm extraction by open biopsy (TESE). Methods: The outcomes of ICSI and IVF-ET were evaluated and compared among 3 groups. Seventy three men suffering from infertility due to obstructive azoospermia had 107 ICSI cycles using MESA (21 cycles in 15 patients), PESA (26 cycles in 17 patients) and TESE (60 cycles in 41 patients). Results: In the clinical outcomes in patients undergoing ICSI with epididymal or testicular sperm, there were no significant differences in fertilization rate (66.1% vs. 60.5%), cleavage rate (94.9% vs. 97.6%), cumulative embryo score (CES) (51.3 vs. 58.8), implantation rate (7.9% vs. 6.1), and clinical pregnancy rate per ET (30.4% (14/46) vs. 25.4% (15/59)) between both groups. Also, in the clinical outcomes in ICSI patients using MESA, PESA, TESE, there were no significant differences in fertilization rate (61.8%, 69.4%, 60.5%), cleavage rate (92.1%, 97.3%, 97.6%), CES (38.1, 52.0, 58.8), implantation rate (9.5%, 6.6%, 6.1%), and clinical pregnancy rate per ET (35% (7/20), 26.9% (7/26), 25.4% (15/59)) among 3 groups. Conclusion: When compared with MESA or TESE, PESA, the clinical outcomes were similar in ICSI patients with obstructive azoospermia whatever the origin or the technique of sperm retrieval. However, we considered PESA is more time-saving and cost effective for ICSI in patients with obstructive azoospermia.

• Animal cells and systems
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• v.14 no.1
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• pp.11-15
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• 2010

Long-term working memory (LTWM) is a subdivision concept of working memory and indicates the enhancement of performance in a working memory task. LTWM has been shown in humans who have been engaged in a specific task requiring working memory over a long time. However, there is very little understanding of the exact mechanism of LTWM because of limitations of experimental methods in human studies. We have modified the standard T-maze task, which is used to test working memory in mice, to demonstrate LTWM in an animal model. We observed an enhancement of performance by repeated experience with the same working memory load in mice, which can be regarded as an LTWM. This effect seems to depend on the condition wherein a delay was given. This task may be a good experimental protocol to assess LTWM in animal studies.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.47.2-47.2
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• 2015

At local, galaxy properties are well known to be clearly different in different environments. However, it is still an open question how this environment-dependent trend has been shaped. In this presentation, we will show the results of our investigation about the evolution of star-formation properties of galaxies over a wide redshift range, from z~2 to z~0.5, focusing its dependence on their stellar mass and environment. In the UKIDSS/UDS region, we estimated photometric redshifts and stellar population properties, such as stellar masses and star-formation rates, using the deep optical and near-infrared data available in this field. Then, we identified galaxy cluster candidates at z~0.5-2. Through the analysis and comparison of star-formation (SF) properties of galaxies in clusters and in field, we found interesting results regarding the evolution of SF properties of galaxies: (1) regardless of redshifts, stellar mass is a key parameter controlling quenching of star formation in galaxies; (2) At z<1, environmental effects become important at quenching star formation regardless of stellar mass of galaxies; and (3) However, the result of the environmental quenching is prominent only for low mass galaxies (M* < $10^{10}M_{\odot}$) since the star formation in most of high mass galaxies are already quenched at z > 1.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.162-162
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• 2012

ZnPc and CuPc molecules stacked similar way in the film, but showed different growth modes in thermal evaporation. The distribution of CuPc crystals did not change by the film thickness, whereas the distribution of ZnPc became random as the increase of the film thickness. The disc type nanograins of CuPc were quite regularly distributed at the initial growth regime and the regular distribution of nanograins was kept during the film growth. On the other hand, ZnPc consisted in ellipsoid shaped nanograins and the distribution of nanograins was not regular in the initial growth regime. The irregular distribution of nanograins changed to the regular mode at the later growth regime by showing structure factor in GISAXS measurement. The different initial nanograin distribution in ZnPc and CuPc was related to the different nanostructure in the mixed layer with C60 to form the bulk heterojunction.

• Fibers and Polymers
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• v.4 no.1
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• pp.15-19
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• 2003

The self-assembly of asymmetric ABC triblock copolymers in the ordered structure is investigated using an isothermal-isobaric molecular dynamics simulation. Unlike symmetric A BC triblock copolymers, more fascinating mophologies are observed in asymmetric ones because of a larger difference of incompatibility between the components. Various modes of self-assembly in assymmetric ABC triblock copolymers are also observed depending on the block composition. When the composition of block A Is changed from 0.125: to 0.25 at the same $f_B$ : 0.25, the morphological transition from the “cylinder in cylinder” to “cylinders at cylinder” structure is observed in the simulation. In the case of ABC triblocks with $f_B$=0.5, a lamellar-type structure is changed to a cylinder-type structure with increasing the length of block A. When the midblock length increases further to $f_B$=0.625, the “spheres on cylinder” structure is observed in both the $A_{10}$$B_{50}$$C_{20}$ and $A_{20}$$B_{50}$$C_{10}$ triblocks. From these results, the phase diagram of ABC triblock copolymers can be constructed.

• Journal of Veterinary Clinics
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• v.32 no.1
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• pp.123-126
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• 2015

A 14-year-old, male Shih-tzu was presented with glaucoma in the left eye. Menace response was negative in the left eye. On ophthalmic examination, exotropia, buphthalmos, bulging of upper lateral globe and episcleral injection was detected in the left eye. Also, there was corneal edema, corneal pigmentation and hyphema in the left eye. The pupil was difficult to observe due to corneal lesions in the left eye. On ultrasonographic examination, an amorphous large mass protruding from the region of the optic disc into the vitreous was observed in the left eye. Enucleation was performed in the left eye. Histologically, the left intraocular mass was diagnosed as glioma. Immunohistochemically, the neoplastic cells were positive to glial fibrillary acidic protein.

• Journal of Korean Neurosurgical Society
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• v.52 no.5
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• pp.466-471
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• 2012

Objective : The aim of this study was to devise an objective clustering method for magnetoencephalography (MEG) interictal spike sources, and to identify the prognostic value of the new clustering method in adult epilepsy patients with cortical dysplasia (CD). Methods : We retrospectively analyzed 25 adult patients with histologically proven CD, who underwent MEG examination and surgical resection for intractable epilepsy. The mean postoperative follow-up period was 3.1 years. A hierarchical clustering method was adopted for MEG interictal spike source clustering. Clustered sources were then tested for their prognostic value toward surgical outcome. Results : Postoperative seizure outcome was Engel class I in 6 (24%), class II in 3 (12%), class III in 12 (48%), and class IV in 4 (16%) patients. With respect to MEG spike clustering, 12 of 25 (48%) patients showed 1 cluster, 2 (8%) showed 2 or more clusters within the same lobe, 10 (40%) showed 2 or more clusters in a different lobe, and 1 (4%) patient had only scattered spikes with no clustering. Patients who showed focal clustering achieved better surgical outcome than distributed cases (p=0.017). Conclusion : This is the first study that introduces an objective method to classify the distribution of MEG interictal spike sources. By using a hierarchical clustering method, we found that the presence of focal clustered spikes predicts a better postoperative outcome in epilepsy patients with CD.

• Journal of Veterinary Clinics
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• v.35 no.6
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• pp.282-285
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• 2018

A 7 years old, male, Afghan hound (case 1) and a 10 years old, castrated male, Pekingese (case 2) were referred with dyspnea. In case 1, thoracic radiographs showed moderate amount of pleural effusion and lobar sign in the left cranial lung lobe. Following computed tomographic (CT) examination, lung lobe torsion in left cranial lung lobe was diagnosed. In case 2, thoracic radiographs showed increased cranial lobar opacity but there was no evidence of pleural effusion. CT examination revealed an abrupt ending bronchus in the left cranial lung lobe. Based on the imaging diagnosis, left cranial lung lobectomy was performed in both cases. Case 1 showed increased lobar opacity and pleural effusion, while case 2 just showed less concrete evidence of lung lobe torsion on thoracic radiographs and marked severe chronic suppurative pneumonia was histopathologically confirmed. In conclusion, CT could be an important modality when atypical lung disease is suspicious.

• Journal of the korean academy of Pediatric Dentistry
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• v.51 no.1
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• pp.66-79
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• 2024

This study aimed to assess the prevalence and distribution pattern of dental anomalies in the permanent teeth of patients with non-syndromic cleft lip with or without cleft palate. Additionally, it aimed to compare differences in dental anomalies between cleft and non-cleft areas, considering gender and cleft phenotype. Panoramic radiographs of 164 patients diagnosed with non-syndromic orofacial clefts were retrospectively analyzed by a single examiner to confirm dental anomalies. The dental anomalies investigated included tooth agenesis, supernumerary teeth, microdontia, rotation, ectopic eruption, and enamel hypoplasia. Cleft phenotypes were categorized into 7 types based on medical and dental records. A significantly higher prevalence of supernumerary teeth was observed in males than females within non-cleft areas (p = 0.017), with no significant differences in other dental anomalies. In non-cleft area, patients with cleft palate exhibited a high prevalence of tooth agenesis (p < 0.0001) and microdontia (p = 0.012) compared to other cleft phenotypes. Maxillary incisor rotation was closely associated with adjacent tooth agenesis in unilateral cleft lip and palate cases (p = 0.034). This study suggests that the additional subphenotype based on dental anomalies in patients with orofacial cleft may serve as applicable clinical markers.