Standardization of the first Korean national reference standard for snake () antivenom.

In 2017, the second national reference standard (NRS) for Gloydius snake venom was established to replace the first NRS for Gloydius snake venom. In connection with the second venom NRS, a candidate for the first NRS for Gloydius snake antivenom was produced in 2017. In this study, the qualification of the candidate was estimated and the potency was determined by a collaborative study.

Beneficial effect of diosgenin as a stimulator of NGF on the brain with neuronal damage induced by Aβ-42 accumulation and neurotoxicant injection.

To investigate the beneficial effects of diosgenin (DG) on the multiple types of brain damage induced by Aβ-42 peptides and neurotoxicants, alterations in the specific aspects of brain functions were measured in trimethyltin (TMT)-injected transgenic 2576 (TG) mice that had been pretreated with DG for 21 days. Multiple types of damage were successfully induced by Aβ-42 accumulation and TMT injection into the brains of TG mice. However, DG treatment significantly reduced the number of Aβ-stained plaques and dead cells in the granule cells layer of the dentate gyrus.

Monitoring of antibiotic resistance in bacteria isolated from laboratory animals.

The drug resistance of microorganisms isolated from laboratory animals never treated with antibiotics is being reported consistently, while the number of laboratory animals used in medicine, pharmacy, veterinary medicine, agriculture, nutrition, and environmental and health science has increased rapidly in Korea. Therefore, this study examined the development of antimicrobial resistance in bacteria isolated from laboratory animals bred in Korea. A total of 443 isolates (7 species) containing 5 Sphingomonas paucimobilis, 206 Escherichia coli, 60 Staphylococcus aureus, 15 Staphylococcus epidermidis, 77 Enterococcus faecalis, 27 Citrobacter freundii, 35 Acinetobacter baumannii were collected from the nose, intestine, bronchus and reproductive organs of ICR mice and SD rats.

IL-6, VEGF, KC and RANTES are a major cause of a high irritant dermatitis to phthalic anhydride in C57BL/6 inbred mice.

Background: In previous studies, several strains of mice were used as chemical-induced skin irritation models to identify immunological hazards and elucidate the molecular and cellular mechanisms by which irritant dermatitis disease occur. BALB/c and C57BL/6 mice have been used for most of these experiments. Although there are some differences in the immune response to chemical allergens between these strains, few studies have been conducted to determine what regulatory factors contribute to these variations.

Effects of air transportation cause physiological and biochemical changes indicative of stress leading to regulation of chaperone expression levels and corticosterone concentration.

Laboratory animals generally experience numerous unfamiliar environmental and psychological influences such as noises, temperatures, handling, shaking, and smells during the process of air transportation. To investigate whether stress induced by air transportation affects stress-related factors in animals, the levels of hormone and chaperone protein were measured in several tissues of F344 rats transported for 13 h and not transported. Herein, we conclude that the levels of corticosterone, HSP70, and GRP78 were significantly increased in the transported group compare to not transported group, but they were rapidly restored to the not transported group level after a recovery period of one week.

Microarray analysis of insulin-regulated gene expression in the liver: the use of transgenic mice co-expressing insulin-siRNA and human IDE as an animal model.

To characterize the changes in global gene expression in the livers of H1/siRNAinsulin-CMV/hIDE transgenic (Tg) mice in response to the reduced bioavailability of insulin, total RNA extracted from the livers of 20-week-old Tg and non-Tg mice was converted to cDNA, labeled with biotin and hybridized to oligonucleotide microarrays. The microarray results were confirmed by a real-time reverse transcription-polymerase chain reaction. Two hundred and fifty-one and 73 genes were up- and down-regulated, respectively by insulin in H1/siRNAinsulin-CMV/hIDE Tg mice compared to the controls.

Selenium acts as an insulin-like molecule for the down-regulation of diabetic symptoms via endoplasmic reticulum stress and insulin signalling proteins in diabetes-induced non-obese diabetic mice.

To investigate whether selenium (Sel) treatment would impact on the onset of diabetes,we examined serum biochemical components including glucose and insulin,endoplasmic reticulum (ER) stress and insulin signalling proteins, hepatic C/EBP-homologous protein (CHOP) expression and DNA fragmentation in diabetic and non- diabetic conditions of non-obese diabetic (NOD) mice. We conclude that (i) Sel treatment induced insulin-like effects in lowering serum glucose level in Sel-treated NOD mice, (ii) Sel-treated mice had significantly decreased serum biochemical components associated with liver damage and lipid metabolism, (iii) Sel treatment led to the activation of the ER stress signal through the phosphorylation of JNK and eIF2 protein and insulin signal mechanisms through the phosphorylation of Akt and PI3 kinase, and (iv) Sel-treated mice were significantly relieved apoptosis of liver tissues indicated by DNA fragmentation assay in the diabetic NOD group. These results suggest that Sel compounds not only serve as insulin-like molecules for the downregulation of glucose level and the incidence of liver damage, but may also have the potential for the development of new drugs for the relief of diabetes by activating the ER stress and insulin signalling pathways.

Significant change in insulin production, glucose tolerance and ER stress signaling in transgenic mice coexpressing insulin-siRNA and human IDE.

The dual expression system for the suppression and clearance of insulin has not been previously used to produce transgenic mice for diabetes-related disease. The aim of this study was to produce new transgenic mice coexpressing specific insulin small interfering RNA (siRNA) sequences and the human insulin degrading enzyme (hIDE) gene in order to examine the diabetes-like phenotype. To achieve this, a new lineage of transgenic mice was produced by the microinjection of the dual expression constructs (pH1/siRNAinsulin-CMV/hIDE) into mouse fertilized eggs.