1.The Evolving Policy Debate on Border Closure in Korea
SuJin KANG ; Jihyun MOON ; Heewon KANG ; Heekyoung NAM ; Sangwoo TAK ; Sung-Il CHO
Journal of Preventive Medicine and Public Health 2020;53(5):302-306
Objectives:
In this paper, we aimed to investigate the evolving debate over border closure in Korea during the coronavirus disease 2019 (COVID-19) pandemic, to address the main themes associated with border closure, and to discuss the factors that need to be considered when making such decisions.
Methods:
We collated and reviewed previously conducted review studies on border closures during infectious disease outbreaks to derive relevant themes and factors.
Results:
According to our systematic review on border closures and travel restrictions, the effects of such containment efforts are limited. We suggest considering the following factors when determining whether to impose border closure measures: (1) disease characteristics, (2) timeliness of implementation, (3) transmission delay and the basic reproduction number, (4) globalization and pandemics, and (5) social and economic costs.
Conclusions
Our assessment indicates that the effects of border closures are at best temporary and limited. Alternative measures must be contemplated and implemented to suppress the spread of COVID-19 in particular and infectious diseases more broadly.
2.Dangyuja (Citrus grandis Osbeck) Peel Improves Lipid Profiles and Alleviates Hypertension in Rats Fed a High-Fat Diet.
Hyun Ju HONG ; Ju Youn JIN ; Heekyoung YANG ; Won Young KANG ; Dong Geon KIM ; Sunyi LEE ; Younghun CHOI ; Jae Hoon KIM ; Chang Hoon HAN ; Young Jae LEE
Laboratory Animal Research 2010;26(4):361-367
Obesity is a major public health problem and significant risk factor for many serious diseases including coronary artery disease, cancer, and diabetes. This study was performed to investigate the hypolipidemic effects and anti-hypertensive effect of Dangyuja (Citrus grandis Osbeck) peel, which is bred on Jeju island, in rats fed a high-fat diet. This study was conducted on 4 equal rat groups which were fed as follows; normal diet group (ND), high fat diet group (HFD), high fat diet supplemented with powdered peel of Dangyuja (1%, wt/wt) group (HFD+Dangyuja), and high fat diet treated with sibutramine simultaneously at a dose of 10 mg/kg group (HFD+Sibutramine). After feeding the high fat diet, body weight gain and relative weight of adipose tissues and liver significantly increased in HFD group, but Dangyuja peel supplementation protected these HFD-induced changes. The levels of serum triglyceride, total cholesterol, low-density lipoprotein (LDL)-cholesterol, and the atherogenic index significantly decreased in the HFD+Dangyuja peel group compared with the HFD group. The systolic blood pressure was significantly increased by feeding the high fat diet, whereas the supplementation of Dangyuja peel effectively prevented the elevation of blood pressure. Therefore, these results suggest that Dangyuja exerts a beneficial effect on obesity by improving lipid metabolism and alleviating obesity-related hypertension.
Animals
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Blood Pressure
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Body Weight
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Cholesterol
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Coronary Artery Disease
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Cyclobutanes
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Diet
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Diet, High-Fat
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Hypertension
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Lipid Metabolism
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Lipoproteins
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Liver
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Obesity
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Public Health
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Rats
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Risk Factors
3.Efficient Liquid Media for Encystation of Pathogenic Free-Living Amoebae.
Hae Jin SOHN ; Heekyoung KANG ; Ga Eun SEO ; Jong Hyun KIM ; Suk Yul JUNG ; Ho Joon SHIN
The Korean Journal of Parasitology 2017;55(3):233-238
Pathogenic Naegleria fowleri, Acanthamoeba castellanii, and Acanthamoeba polyphaga, are distributed worldwide. They are causative agents of primary amoebic meningoencephalitis or acanthamoebic keratitis in humans, respectively. Trophozoites encyst in unfavorable environments, such as exhausted food supply and desiccation. Until recently, the method of N. fowleri encystation used solid non-nutrient agar medium supplemented with heat-inactivated Escherichia coli; however, for the amoebic encystment of Acanthamoeba spp., a defined, slightly modified liquid media is used. In this study, in order to generate pure N. fowleri cysts, a liquid encystment medium (buffer 1) modified from Page’s amoeba saline was applied for encystation of N. fowleri. N. fowleri cysts were well induced after 24 hr with the above defined liquid encystment medium (buffer 1). This was confirmed by observation of a high expression of differential mRNA of nfa1 and actin genes in trophozoites. Thus, this liquid medium can replace the earlier non-nutrient agar medium for obtaining pure N. fowleri cysts. In addition, for cyst formation of Acanthamoeba spp., buffer 2 (adjusted to pH 9.0) was the more efficient medium. To summarize, these liquid encystment media may be useful for further studies which require axenic and pure amoebic cysts.
Acanthamoeba
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Acanthamoeba castellanii
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Actins
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Agar
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Amoeba*
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Desiccation
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Escherichia coli
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Food Supply
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Humans
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Hydrogen-Ion Concentration
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Keratitis
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Meningoencephalitis
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Methods
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Naegleria fowleri
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RNA, Messenger
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Trophozoites
4.Anti-oxidant activities of kiwi fruit extract on carbon tetrachloride-induced liver injury in mice.
Wonyoung KANG ; Heekyoung YANG ; Hyun Ju HONG ; Chang Hoon HAN ; Young Jae LEE
Korean Journal of Veterinary Research 2012;52(4):275-280
The kiwi (Actinidia deliciosa) is well known to contain anti-oxidants. In this study, we investigated the anti-oxidant effects of kiwi extract on carbon tetrachloride (CCl4) induced liver injury in BALB/c mice. The radical scavenging effect of 80% methanol extract of Halla-Gold kiwi was observed. For the animal study, mice were randomly divided into four groups: normal group, CCl4-induced model group, kiwi extract administered group, and silymarin treated group. The kiwi extract was provided daily for 10 days. At the 24 h after last administration, CCl4 was injected. The kiwi extract showed strong inhibitory effect of DPPH radicals and superoxide scavenging. In animal study, administration of CCl4 resulted in significantly elevated plasma levels of ALT and AST but they decreased in kiwi-extract pretreated group. Anti-oxidant enzymes such as GSH-px and GSH-rd were restored in the kiwi extract treatment group. Histopathological degeneration was also prevented in the kiwi extract treated group compared with of the control group, which exhibited CCl4-induced hepatotoxicity. On the basis of the obtained results, it can be concluded that kiwi extract showed protective effects, not only as anti-oxidant effects, but also in the protection of hepatotoxicity in CCl4-intoxicated mice.
Animals
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Antioxidants
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Carbon
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Carbon Tetrachloride
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Cytochrome P-450 CYP2E1
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Fruit
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Liver
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Methanol
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Mice
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Plasma
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Silymarin
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Superoxides
5.Cytopathic Change and Inflammatory Response of Human Corneal Epithelial Cells Induced by Acanthamoeba castellanii Trophozoites and Cysts
Hae Jin SOHN ; Ga Eun SEO ; Jae Ho LEE ; A Jeong HAM ; Young Hwan OH ; Heekyoung KANG ; Ho Joon SHIN
The Korean Journal of Parasitology 2019;57(3):217-223
Acanthamoeba castellanii has ubiquitous distribution and causes primary acanthamoebic keratitis (AK). AK is a common disease in contact lens wearers and results in permanent visual impairment or blindness. In this study, we observed the cytopathic effect, in vitro cytotoxicity, and secretion pattern of cytokines in human corneal epithelial cells (HCECs) induced by A. castellanii trophozoites and/or cysts. Morphological observation revealed that panked dendritic HCECs co-cultured with amoeba cysts had changed into round shape and gradually died. Such changes were more severe in co-culture with cyst than those of co-cultivation with trophozoites. In vitro cytotoxicity assay revealed the highest cytotoxicity to HCECs in the co-culture system with amoeba cysts. A. castellanii induced the expression of IL-1α, IL-6, IL-8, and CXCL1 in HCECs. Secreted levels of IL-1α, IL-6, and IL-8 in HCECs co-cultured with both trophozoites and cysts were increased at an early incubation time (3 and 6 hr). These results suggested that cytopathic changes and pro-inflammatory cytokines release of HCECs in response to A. castellanii, especially amoebic cysts, are an important mechanism for AK development.
Acanthamoeba castellanii
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Acanthamoeba
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Amoeba
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Blindness
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Coculture Techniques
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Cytokines
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Epithelial Cells
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Humans
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In Vitro Techniques
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Interleukin-6
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Interleukin-8
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Keratitis
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Trophozoites
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Vision Disorders
6.Multiple Endocrine Neoplasia Type 1 with Multiple Leiomyomas Linked to a Novel Mutation in the MEN1 Gene.
Heekyoung CHOI ; Sehyun KIM ; Jae Hoon MOON ; Yoon Hee LEE ; Yumie RHEE ; Eun Seok KANG ; Chul Woo AHN ; Bong Soo CHA ; Eun Jig LEE ; Kyung Rae KIM ; Hyun Chul LEE ; Seon Yong JEONG ; Hyun Ju KIM ; Sung Kil LIM
Yonsei Medical Journal 2008;49(4):655-661
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominantly inherited syndrome. MEN1 is characterized by the presence of functioning and nonfunctioning tumors or hyperplasia of the pituitary gland, parathyroid glands, and pancreatic islet cells. In addition, MEN1 carriers can have adrenal or thyroid tumors and non-endocrine tumors, such as lipomas, angiofibromas, and leiomyomas. Although leiomyoma is not a major component of MEN1, it is thought to occur more frequently than expected. However, there has been no report of a case of MEN1 with leiomyoma in Korea so far. This report describes a patient with multiple leiomyomas in MEN1. A 50-year-old woman was referred for further evaluation of elevated calcium levels and osteoporosis. Biochemical abnormalities included hypercalcemia with elevated parathyroid hormone. There was hyperprolactinemia with pituitary microadenoma in sella MRI. An abdominal MRI demonstrated adrenal nodules and leiomyomas in the bladder and uterus. Endoscopic ultrasonography demonstrated esophageal leiomyoma and pancreatic islet cell tumor. A subtotal parathyroidectomy with thymectomy was performed. Sequencing of the MEN1 gene in this patient revealed a novel missense mutation (D350V, exon 7). This is the first case of MEN1 accompanied with multiple leiomyomas, parathyroid adenoma, pituitary adenoma, pancreatic tumor, and adrenal tumor.
Base Sequence
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Female
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Humans
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Leiomyomatosis/genetics/*metabolism/*pathology/radiography
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Magnetic Resonance Imaging
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Middle Aged
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Multiple Endocrine Neoplasia Type 1/genetics/*metabolism
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Mutation/genetics