• Journal of Veterinary Clinics
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• v.35 no.4
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• pp.126-129
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• 2018

This study was performed to describe the outcome of pars plana retinopexy with perfluoro-n-octane (PFO)-silicone oil (SiO) exchange in dogs with rhegmatogenous retinal detachment in Seoul National University Veterinary Medical Teaching Hospital (SNU VMTH) from 2014 to 2017. Nine eyes of 8 dogs were included in this study. Medical records including signalment, history, duration from onset of blindness to surgical intervention, pre-operative findings, duration from surgery to regaining vision, and post-operative complications were evaluated. No eyes were visual before surgery. Duration from onset of blindness to surgical intervention was 2-30 days (median 8 days); duration from surgery to regain vision was 1-14 days (median 6 days); follow-up time was 15-1088 days (median 69 days). Post-operative complications were divided as temporary vs permanent conditions. Temporary complications were corneal ulcer, uveitis, retinal haemorrhage, glaucoma, subconjunctival leakage of SiO, and vitreal haemorrhage. Permanent complications were anterior chamber migration of SiO, retinal degeneration, corneal degeneration, re-detachment, and cataract. Six of 9 eyes regained functional vision, five of which remained visual throughout the follow-up time while the other one lost vision after 3 months because of uveitic glaucoma. In conclusion, pars plana retinopexy with PFO-SiO exchange provided fair outcome in 66.7% cases described in this study.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.113-113
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• 2001

Dopamine, a principal neurotransmitter in the central nervous system, accounts for 90% of total catecholamines. It serves as a precursor of certain hormones, melanins, noradrenalin and adrenalin. Parkinsonian disease (PD) is characterized by selective loss of dopaminergic neurons in the substantia nigra pars compacta and a significant dimunution in the neostriatal content of dopamine and its metabolites.(omitted)

• Journal of Korean Neurosurgical Society
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• v.55 no.4
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• pp.212-214
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• 2014

The synchondrosis between the dens and the body of axis normally fuses between 5 and 7 years of age. Until this age, synchondrosis fractures can occur in children. Most synchondrosis fractures are conventionally treated by external immobilization alone. We report a 10-year-old child with odontoid synchondrosis fracture who was treated by C1 lateral mass and C2 pars screw rod fixation with a successful outcome and discuss the possible reasons for occurrence of odontoid synchondrosis fracture in this older child as well as the indications for surgery in this condition.

• Animal cells and systems
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• v.1 no.3
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• pp.475-482
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• 1997

The antiserum against locustatachykinin I, originally isolated from brain and retrocerebral complex of the locust Locusta migratoria, has been used to investigate changes in number, localization, and structure of locustatachykinin I-immunoreactive (LomTK I-IR) neurons in the brains of the common cutworm, Spodoptera Iitura, during postembryonic development. These neurons are found at larval, pupal, and adult stages. In the larval stages, the first instar larva shows the first appearance of about 8 LomTK I-IR neurons. These neurons gradually increase in number from the second to fourth instar larvae which have the largest number of about 92 in all postembryonic stages. Thereafter, these neurons decrease to about 28 in number in the 5-day-old pupa. However, they begin to rise again from the 7-day-old pupal stage, eventually reaching to about 90 in the l-day-old adult. The developing larval brains contain cell bodies of these neurons in most neuromeres. After the metamorphosis of larva to pupa and adult, localization of these neuronal cell bodies is confined to the specific cerebral neuromeres. The 7-day-old pupal brain shows the location of these neuronal cell bodies in pars intercerebralis, pars lateralis of protocerebrum, deutocerebrum, tritocerebrum, optic lobe-near region, and subesophageal ganglion. In the l-day-old adult, however, the brain has these cell bodies only in some neuromeres of protocerebrum, deutocerebrum, and subesophageal ganglion. Throughout the postembryonic life, changes in structure of these neurons coincide with changes in number and localization of these neurons. These findings suggest that changes in number, localization, and structure of these neurons reflect differentiation of these neurons to adult type.

• Applied Microscopy
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• v.14 no.2
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• pp.52-65
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• 1984

The ultrastructure of the pars distalis of the adenohypophysis was studied in the female Korean native goat ($10{\sim}16kg$, B.W.) by electron microscopy. Six granular cells and one agranular cell were recognized according to the characteristic patterns of secretory granules and cell organelles. Type I cells were. large, round or oval and contained the largest granules of 290 to 490 nm in diameter, Their endoplasmic reticula were well developed and packed with parallel lamellae close to nuclear membrane. Type II cells were elongate or polygonal. They contained granules of 220 to 390 nm in diameter and well developed Golgi complex. Type III cells were round, oval or angular and contained granules of 150 to 300 nm in diameter. Their endoplasmic reticula were coarsely scattered among the granules and provided an intracellular compartment for segregation in groups. Type IV cells were oval or round and contained granules of 120 to 280 nm in diameter. Their endoplasmic reticula were arranged at one pole of cytoplasm. Type V cells were round or polygonal and contained small granules of 110 to 140 nm in diameter Their endoplasmic reticula were packed with regularly parallel lamellae. Type VI cells were stellate and irregular in shape and had cytoplasmic processes projecting between the neighboring cells. Their granules were less than 130 nm in diameter, the smallest among the cells of the pars distalis. Agranular cells had no granules or a few, if any. They were stellate or irregular in shape.

• Journal of Korean Neurosurgical Society
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• v.49 no.6
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• pp.351-354
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• 2011

Objective : This investigation was conducted to evaluate a new, safe entry point for the C2 pedicle screw, determined using the anatomical landmarks of the C2 lateral mass, the lamina, and the isthmus of the pars interarticularis. Methods : Fifteen patients underwent bilateral C1 lateral mass-C2 pedicle screw fixation, combined with posterior wiring. The C2 pedicle screw was inserted at the entry point determined using the following method : 4 mm lateral to and 4 mm inferior to the transitional point (from the superior end line of the lamina to the isthmus of the pars interarticularis). After a small hole was made with a high-speed drill, the taper was inserted with a 30 degree convergence in the cephalad direction. Other surgical procedures were performed according to Harm's description. Preoperatively, careful evaluation was performed with a cervical X-ray for C1-C2 alignment, magnetic resonance imaging for spinal cord and ligamentous structures, and a contrast-enhanced 3-dimensional computed tomogram (3-D CT) for bony anatomy and the course of the vertebral artery. A 3-D CT was checked postoperatively to evaluate screw placement Results : Bone fusion was achieved in all 15 patients (100%) without screw violation into the spinal canal, vertebral artery injury, or hardware failure. Occipital neuralgia developed in one patient, but this subsided after a C2 ganglion block. Conclusion : C2 transpedicular screw fixation can be easily and safely performed using the entry point of the present study. However, careful preoperative radiographic evaluation, regardless of methods, is mandatory.

• Journal of Preventive Medicine and Public Health
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• v.50 no.6
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• pp.347-360
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• 2017

Objectives: This meta-analysis aimed to evaluate congenital malformations in infants conceived by assisted reproductive techniques (ART), compared with infants conceived spontaneously. Methods: In this study, available resources searched to find relevant articles included PubMed, ScienceDirect, Scopus, Google Scholar, Cochrane, ProQuest, Iranmedex, Magiran, and Scientific Information Database. After extracting the necessary information from evaluated articles, meta-analysis on the articles' data was performed using Stata version 11.2. Results: In this study, from a total of 339 articles, extracted from the initial investigation, ultimately 30 articles were selected for meta-analysis that assessed the use of ART on the risk of congenital abnormalities and some birth complications on 5 470 181 infants (315 402 cases and 5 154 779 controls). The odds ratio (95% confidence interval [CI]) for low birth weight was 1.89 (95% CI, 1.36 to 2.62), preterm labor 1.79 (95% CI, 1.21 to 2.63), cardiac abnormalities 1.43 (95% CI, 1.27 to 1.62), central nervous system abnormalities 1.36 (95% CI, 1.10 to 1.70), urogenital system abnormalities 1.58 (95% CI, 1.28 to 1.94), musculoskeletal disorders 1.35 (95% CI, 1.12 to 1.64), and chromosomal abnormalities in infants conceived by ART was 1.14 (95% CI, 0.90 to 1.44), which were all statistically significant, except chromosomal abnormalities. Conclusions: The risk of congenital abnormalities and some birth complications were significantly higher in ART than normal conception, while chromosomal abnormalities were not; therefore, the application of ART should be selected individually for patients by detailed assessment to reduce such risks in the population.

• Journal of Preventive Medicine and Public Health
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• v.53 no.3
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• pp.151-157
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• 2020

Objectives: The outbreak of coronavirus disease 2019 (COVID-19) is one of the main public health challenges currently facing the world. Because of its high transmissibility, COVID-19 has already caused extensive morbidity and mortality in many countries throughout the world. An accurate estimation of the basic reproduction number (R₀) of COVID-19 would be beneficial for prevention programs. In light of discrepancies in original research on this issue, this systematic review and meta-analysis aimed to estimate the pooled R₀ for COVID-19 in the current outbreak. Methods: International databases (including Google Scholar, Science Direct, PubMed, and Scopus) were searched to identify studies conducted regarding the R₀ of COVID-19. Articles were searched using the following keywords: "COVID-19" and "basic reproduction number" or "R₀." The heterogeneity among studies was assessed using the I² index, the Cochran Q test, and T². A random-effects model was used to estimate R₀ in this study. Results: The mean reported R₀ in the identified articles was 3.38±1.40, with a range of 1.90 to 6.49. According to the results of the random-effects model, the pooled R₀ for COVID-19 was estimated as 3.32 (95% confidence interval, 2.81 to 3.82). According to the results of the meta-regression analysis, the type of model used to estimate R₀ did not have a significant effect on heterogeneity among studies (p=0.81). Conclusions: Considering the estimated R₀ for COVID-19, reducing the number of contacts within the population is a necessary step to control the epidemic. The estimated overall R₀ was higher than the World Health Organization estimate.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.26-32
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• 2015

During the course of a severe accident in a light water nuclear reactor, large amounts of hydrogen can be generated and released into the containment during reactor core degradation. Additional burnable gases [hydrogen ($H_2$) and carbon monoxide (CO)] may be released into the containment in the corium/concrete interaction. This could subsequently raise a combustion hazard. As the Fukushima accidents revealed, hydrogen combustion can cause high pressure spikes that could challenge the reactor buildings and lead to failure of the surrounding buildings. To prevent the gas explosion hazard, most mitigation strategies adopted by European countries are based on the implementation of passive autocatalytic recombiners (PARs). Studies of representative accident sequences indicate that, despite the installation of PARs, it is difficult to prevent at all times and locations, the formation of a combustible mixture that potentially leads to local flame acceleration. Complementary research and development (R&D) projects were recently launched to understand better the phenomena associated with the combustion hazard and to address the issues highlighted after the Fukushima Daiichi events such as explosion hazard in the venting system and the potential flammable mixture migration into spaces beyond the primary containment. The expected results will be used to improve the modeling tools and methodology for hydrogen risk assessment and severe accident management guidelines. The present paper aims to present the methodology adopted by Institut de Radioprotection et de $S{\hat{u}}ret{\acute{e}}$ $Nucl{\acute{e}}aire$ to assess hydrogen risk in nuclear power plants, in particular French nuclear power plants, the open issues, and the ongoing R&D programs related to hydrogen distribution, mitigation, and combustion.

• Safety and Health at Work
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• v.7 no.1
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• pp.49-54
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• 2016

Background: Prolonged sitting leads to low back discomfort and lumbopelvic muscle fatigue. This study examined the characteristics of body perceived discomfort and trunk muscle fatigue during 1 hour of sitting in three postures in office workers. Methods: Thirty workers sat for 1 hour in one of three sitting postures (i.e., upright, slumped, and forward leaning postures). Body discomfort was assessed using the Body Perceived Discomfort scale at the beginning and after 1 hour of sitting. Electromyographic (EMG) signals were recorded from superficial lumbar multifidus, iliocostalis lumborum pars thoracis, internal oblique (IO)/transversus abdominis (TrA), and rectus abdominis muscles during 1 hour of sitting. The median frequency (MDF) of the EMG power spectrum was calculated. Results: Regardless of the sitting posture, the Body Perceived Discomfort scores in the neck, shoulder, upper back, low back, and buttock significantly increased after 1 hour of sitting compared with baseline values ($t_{(9)}=-11.97$ to -2.69, p < 0.05). The MDF value of the EMG signal of rectus abdominis, iliocostalis lumborum pars thoracis, and multifidus muscles was unchanged over time in all three sitting postures. Only the right and left IO/TrA in the slumped sitting posture was significantly associated with decreased MDF over time (p = 0.019 to 0.041). Conclusion: Prolonged sitting led to increased body discomfort in the neck, shoulder, upper back, low back, and buttock. No sign of trunk muscle fatigue was detected over 1 hour of sitting in the upright and forward leaning postures. Prolonged slumped sitting may relate to IO/TrA muscle fatigue, which may compromise the stability of the spine, making it susceptible to injury.