• Journal of the Korean neurological association
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• v.36 no.4
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• pp.333-336
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• 2018

Carotid free-floating thrombus (FFT) is a rare cause of stroke. The FFT is commonly associated with an atherosclerotic plaque rupture, but other causes need to be examined in young patients. We report a case of 31-year-old male patient with recurrent ischemic stroke caused by carotid FFT. Although initial laboratory test was unremarkable, recurrent stroke events led us to perform additional study and antiphospholipid syndrome (APLS) was diagnosed. Repetitive testing for APLS seems considerable when young patients present with recurrent stroke.

• Bulletin of the Korean Chemical Society
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• v.17 no.2
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• pp.192-198
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• 1996

We present a theoretical formulation of diffusion process on solid surface based on multidimensional transition state theory (TST). Surface diffusion of single adatom results from hopping processes on corrugated potential surface and is affected by surface vibrations of surface atoms. The rate of rare events such as hopping between lattice sites can be calculated by transition state theory. In order to include the interactions of the adatom with surface vibrations, it is assumed that the coordinates of adatom are coupled to the bath of harmonic oscillators whose frequencies are those of surface phonon modes. When nearest neighbor surface atoms are considered, we can construct Hamiltonians which contain terms for interactions of adatom with surface vibrations for the well minimum and the saddle point configurations, respectively. The escape rate constants, thus the surface diffusion parameters, are obtained by normal mode analysis of the force constant matrix based on the Hamiltonian. The analysis is applied to the diffusion coefficients of W, Ir, Pt and Ta atoms on the bcc(110) plane of W in the zero-coverage limit. The results of the calculations are encouraging considering the limitations of the model considered in the study.

• Journal of Medicine and Life Science
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• v.17 no.3
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• pp.103-106
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• 2020

Bone marrow failure, such as aplastic or myelophthisic anemia, can occur due to an underlying lymphoid malignancy and cause life-threatening events. A 58-year-old man diagnosed with angioimmunoblastic T-cell lymphoma had recently visited the emergency department because of an altered level of consciousness caused by acute severe anemia. The laboratory findings were strongly suggestive of bone marrow failure syndrome. Bone marrow examination was immediately performed and, subsequently, dexamethasone was initiated to control the underlying lymphoma. Intravenous immunoglobulin was also administered in combination due to combined immune hemolytic anemia and thrombocytopenia. Bone marrow examination revealed a packed marrow with marked fibrosis and lymphoma involvement. A diagnosis of secondary myelofibrosis related to the underlying lymphoma was made, and sequential combination chemotherapy was introduced despite the presence of severe anemia and thrombocytopenia. After combination chemotherapy, his hematologic profile and underlying lymphoma improved. Better understanding of various hematologic manifestations and knowledge of the rare condition of lymphoma are essential for appropriate diagnostic approaches and treatment.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.22 no.2
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• pp.46-52
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• 2022

Inborn errors of metabolism (IEM) are very rare and genetically transmitted diseases and have man y different symptoms related with multisystemic involvement. More rarely, endocrinopathies can be an early and first symptom of IEM, but presents with signs of later complications in adolescent or adulthood. The mechanisms of endocrine dysfunction in IEM are poorly understood. Hypogonadotropic hypogonadism is common in hemochromatosis, adrenoleukodystrophy, galactosemia, and glycogen storage disease. Many girls with classic galactosemia are at high risk for premature ovarian insufficiency (POI), despite an early diagnosis and good control. Mitochondrial diseases are multisystem disorders and are characterized by hypo- and hypergonadotrophic hypogonadism, thyroid dysfunction and insulin dysregulation. Glycogen storage disorders (GSDs), especially type Ia, Ib, III, V are assocciated with frequent hypoglycemic events. IEM is a growing field and is not yet well recognized despite its consequences for growth, bone metabolism and fertility. For this reason, clinicians should be aware of these diagnoses and potential endocrine dysfunction.

• Journal of Yeungnam Medical Science
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• v.39 no.1
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• pp.62-66
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• 2022

Immune checkpoint inhibitor (ICI)-associated adrenal insufficiency is rare but may become a serious adverse event in patients treated with ICIs. The present case report documents two cases of adrenal insufficiency developed during chemotherapy plus tislelizumab (百泽安, Baize'an; BeiGene Ltd.) therapy in patients with advanced gastric cancer. Adrenal insufficiency developed after 6 and 13 cycles of treatment and was well controlled with hydrocortisone. The patients also developed hypothyroidism, which was managed with levothyroxine. Two patients showed a partial response, and one patient out of two achieved a near-complete response, sustaining over 11 months. Increased awareness of ICI-related adrenal insufficiency is crucial for early detection and prompt management of patients treated with ICIs.

• Journal of Dental Anesthesia and Pain Medicine
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• v.23 no.5
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• pp.287-291
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• 2023

Sugammadex has shown faster reversal of steroidal neuromuscular blockade (NMB) than neostigmine, a traditional reversal agent for NMB, even in the intense block phase. This efficiency is possible because of the unique mechanism of action by encapsulating the NMB molecules. Therefore, with the use of sugammadex, we can also expect to avoid direct interactions with the cholinergic system and its subsequent side effects, which are disadvantages of traditional drugs. However, despite these benefits and US Food and Drug Administration (FDA) approval in 2015, rare adverse events associated with sugammadex have been reported. Herein, we report a case of bronchospasm that developed immediately after sugammadex administration.

• Communications for Statistical Applications and Methods
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• v.30 no.6
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• pp.531-550
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• 2023

The estimation of extreme quantiles is one of the main objectives of statistics of extremes (which deals with the estimation of rare events). In this paper, a robust estimator of extreme quantile of a heavy-tailed distribution is considered. The estimator is obtained through the minimum density power divergence criterion on an exponential regression model. The proposed estimator was compared with two estimators of extreme quantiles in the literature in a simulation study. The results show that the proposed estimator is stable to the choice of the number of top order statistics and show lesser bias and mean square error compared to the existing extreme quantile estimators. Practical application of the proposed estimator is illustrated with data from the pedochemical and insurance industries.

• Journal of Korean Neurosurgical Society
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• v.67 no.3
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• pp.345-353
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• 2024

Objective : Blood-blister aneurysms (BBAs) of the internal carotid artery (ICA) are challenging lesions with high morbidity and mortality rates. Although research on BBAs is well documented in different populations, the study of BBAs in the Tibetan population is extremely rare. This study aimed to evaluate the characteristics of BBAs and analyze the treatment modalities and long-term outcomes in the Tibetan population in comparison with the Han population. Methods : The characteristics of patients with BBAs of the ICA from January 2009 to January 2021 at our institution were reviewed. The features of aneurysms, treatment modalities, complications, and follow-up outcomes were retrospectively analyzed. Results : A total of 130 patients (41 Tibetan and 89 Han patients) with BBAs of the ICA who underwent treatment were enrolled. Compared with the Han group, the Tibetan group significantly demonstrated a high ratio of BBAs among ICAs (8.6%, 41/477 vs. 1.6%, 89/5563; p<0.05), a high ratio of vasospasm (34.1%, 14/41 vs. 6.7%, 6/89; p=0.001), a high risk of ischemic events (43.9%, 18/41 vs. 22.5%, 20/89; p<0.05), and a low ratio of good outcomes (modified Rankin scale, 0-2) at the 1-year follow-up (51.2%, 21/41 vs. 74.2%, 66/89; p<0.05). The multivariate regression model showed that ischemic events significantly contributed to the prediction of outcomes at 1 year. Further analysis revealed that microsurgery and vasospasm were associated with ischemic events. Conclusion : In comparison with Han patients, the Tibetan population had a high ratio of BBA occurrence, a high incidence of ischemic events, and a high ratio of poor outcomes. The endovascular approach showed more benefits in BBA patients.

• Tuberculosis and Respiratory Diseases
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• v.73 no.4
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• pp.231-233
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• 2012

Tadalafil is a phosphodiesterase-5 inhibitor (PDE5I), which is widely used to treat erectile dysfunction. Although PDE5Is have excellent safety profiles, and most of the side effects are mild, rare serious adverse events have been reported in association with PDE5Is. Thrombosis is one of those events, and a few previous reports have suggested the association of PDE5Is with thrombosis. We report the case of a 61-year-old male who developed pulmonary embolism combined with pulmonary infarction directly after taking tadalafil. Both the patient and the physician suspected tadalafil as the culprit drug, as the patient was in an otherwise healthy condition. However, after extensive evaluation, we noticed that factor VIII levels were elevated. Prior reports suggesting the association between thrombosis and PDEIs either lack complete information on coagulation factors, or show inconsistencies in their results. Physicians should operate caution prior to accepting the diagnosis of adverse drug reaction.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.710-720
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• 2017

In Korea, many nuclear power plants operate at a single site based on geographical characteristics, but the population density near the sites is higher than that in other countries. Thus, multiunit accidents are a more important consideration than in other countries and should be addressed appropriately. Currently, there are many issues related to a multiunit probabilistic safety assessment (PSA). One of them is the quantification of a multiunit PSA model. A traditional PSA uses a Boolean manipulation of the fault tree in terms of the minimal cut set. However, such methods have some limitations when rare event approximations cannot be used effectively or a very small truncation limit should be applied to identify accident sequence combinations for a multiunit site. In particular, it is well known that seismic risk in terms of core damage frequency can be overestimated because there are many events that have a high failure probability. In this study, we propose a quantification method based on a Monte Carlo approach for a multiunit PSA model. This method can consider all possible accident sequence combinations in a multiunit site and calculate a more exact value for events that have a high failure probability. An example model for six identical units at a site was also developed and quantified to confirm the applicability of the proposed method.