• Animal Bioscience
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• v.37 no.6
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• pp.1021-1030
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• 2024

Objective: R-loops are DNA:RNA triplex hybrids, and their metabolism is tightly regulated by transcriptional regulation, DNA damage response, and chromatin structure dynamics. R-loop homeostasis is dynamically regulated and closely associated with gene transcription in mouse zygotes. However, the factors responsible for regulating these dynamic changes in the R-loops of fertilized mouse eggs have not yet been investigated. This study examined the functions of candidate factors that interact with R-loops during zygotic gene activation. Methods: In this study, we used publicly available next-generation sequencing datasets, including low-input ribosome profiling analysis and polymerase II chromatin immunoprecipitation-sequencing (ChIP-seq), to identify potential regulators of R-loop dynamics in zygotes. These datasets were downloaded, reanalyzed, and compared with mass spectrometry data to identify candidate factors involved in regulating R-loop dynamics. To validate the functions of these candidate factors, we treated mouse zygotes with chemical inhibitors using in vitro fertilization. Immunofluorescence with an anti-R-loop antibody was then performed to quantify changes in R-loop metabolism. Results: We identified DEAD-box-5 (DDX5) and histone deacetylase-2 (HDAC2) as candidates that potentially regulate R-loop metabolism in oocytes, zygotes and two-cell embryos based on change of their gene translation. Our analysis revealed that the DDX5 inhibition of activity led to decreased R-loop accumulation in pronuclei, indicating its involvement in regulating R-loop dynamics. However, the inhibition of histone deacetylase-2 activity did not significantly affect R-loop levels in pronuclei. Conclusion: These findings suggest that dynamic changes in R-loops during mouse zygote development are likely regulated by RNA helicases, particularly DDX5, in conjunction with transcriptional processes. Our study provides compelling evidence for the involvement of these factors in regulating R-loop dynamics during early embryonic development.

• Korean Journal of Poultry Science
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• v.48 no.4
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• pp.193-206
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• 2021

This study aimed to identify the growth performance of Korean indigenous chicken pure-line by sex and twelve strains conserved in Poultry Research Institute, National Institute of Animal Science, Rural Development Administration. The effect of sex and strain on body weight was significantly different in every period, with males being heavier in all periods than females. In the case of biweekly weight gain, the tendency to increase rapidly from birth to six weeks old, and to decrease in the period from twelve to fourteen weeks old was common across all sex and strains. Depending on sex and strain, there were significant differences in age and the number of peaks. Regardless of sex and strain, the determination coefficient and adjusted determination coefficient showed high goodness of fit (99.1~99.9%) to growth functions. However, for each model, the goodness-of-fit had variations by sex and strains. von Betalanffy function had the best fit to growth curves in all the female strains except strain D. On the other hand, Gompertz function had the best fit for all the male strains except strain C. Logistic function showed the lowest goodness-of-fit in all sex and strains. Mature weights were in the order of von bertalanffy, Gompertz, and Logistic models, while growth ratio and maturing rate followed the order of logistic, gompertz, and von bertalanffy functions. This information could be useful for Korean indigenous chicken management and designing crossbreeding tests and breeding programs.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.319-326
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• 1999

Recently, it is continuously rising to concern about the health risk being induced by microorganisms in food such as Escherichia coli O157:H7 and Listeria monocytogenes. Various organizations and regulatory agencies including U.S.FPA, U.S.DA and FAO/WHO are preparing the methodology building to apply microbial quantitative risk assessment to risk-based food safety program. Microbial risks are primarily the result of single exposure and its health impacts are immediate and serious. Therefore, the methodology of risk assessment differs from that of chemical risk assessment. Microbial quantitative risk assessment consists of tow steps; hazard identification, exposure assessment, dose-response assessment and risk characterization. Hazard identification is accomplished by observing and defining the types of adverse health effects in humans associated with exposure to foodborne agents. Epidemiological evidence which links the various disease with the particular exposure route is an important component of this identification. Exposure assessment includes the quantification of microbial exposure regarding the dynamics of microbial growth in food processing, transport, packaging and specific time-temperature conditions at various points from animal production to consumption. Dose-response assessment is the process characterizing dose-response correlation between microbial exposure and disease incidence. Unlike chemical carcinogens, the dose-response assessment for microbial pathogens has not focused on animal models for extrapolation to humans. Risk characterization links the exposure assessment and dose-response assessment and involve uncertainty analysis. The methodology of microbial dose-response assessment is classified as nonthreshold and thresh-old approach. The nonthreshold model have assumption that one organism is capable of producing an infection if it arrives at an appropriate site and organism have independence. Recently, the Exponential, Beta-poission, Gompertz, and Gamma-weibull models are using as nonthreshold model. The Log-normal and Log-logistic models are using as threshold model. The threshold has the assumption that a toxicant is produce by interaction of organisms. In this study, it was reviewed detailed process including risk value using model parameter and microbial exposure dose. Also this study suggested model application methodology in field of exposure assessment using assumed food microbial data(NaCl, water activity, temperature, pH, etc.) and the commercially used Food MicroModel. We recognized that human volunteer data to the healthy man are preferred rather than epidemiological data fur obtaining exact dose-response data. But, the foreign agencies are studying the characterization of correlation between human and animal. For the comparison of differences to the population sensitivity: it must be executed domestic study such as the establishment of dose-response data to the Korean volunteer by each microbial and microbial exposure assessment in food.

• Molecules and Cells
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• v.38 no.9
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• pp.796-805
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• 2015

Gintonin is a novel ginseng-derived lysophosphatidic acid (LPA) receptor ligand. Oral administration of gintonin ameliorates learning and memory dysfunctions in Alzheimer's disease (AD) animal models. The brain cholinergic system plays a key role in cognitive functions. The brains of AD patients show a reduction in acetylcholine concentration caused by cholinergic system impairments. However, little is known about the role of LPA in the cholinergic system. In this study, we used gintonin to investigate the effect of LPA receptor activation on the cholinergic system in vitro and in vivo using wild-type and AD animal models. Gintonin induced $[Ca^{2+}]_i $ transient in cultured mouse hippocampal neural progenitor cells (NPCs). Gintonin-mediated $[Ca^{2+}]_i $ transients were linked to stimulation of acetylcholine release through LPA receptor activation. Oral administration of gintonin-enriched fraction (25, 50, or 100 mg/kg, 3 weeks) significantly attenuated scopolamine-induced memory impairment. Oral administration of gintonin (25 or 50 mg/kg, 1 2 weeks) also significantly attenuated amyloid-${\beta}$ protein ($A{\beta}$)-induced cholinergic dysfunctions, such as decreased acetylcholine concentration, decreased choline acetyltransferase (ChAT) activity and immunoreactivity, and increased acetylcholine esterase (AChE) activity. In a transgenic AD mouse model, long-term oral administration of gintonin (25 or 50 mg/kg, 3 months) also attenuated AD-related cholinergic impairments. In this study, we showed that activation of G protein-coupled LPA receptors by gintonin is coupled to the regulation of cholinergic functions. Furthermore, this study showed that gintonin could be a novel agent for the restoration of cholinergic system damages due to $A{\beta}$ and could be utilized for AD prevention or therapy.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.1
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• pp.106-111
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• 2007

The current study was conducted to determine the optimum length of feed withdrawal for pre-harvest broilers. A total of three hundred broilers were sampled from an industrial population, and 30 chicks for each weight group (e.g., 1.5 and 2.5 kg) were randomly assigned to feed withdrawal treatments for 0, 3, 6, 9 and 12 h. Weight loss, yield, muscle pH, objective meat color and weights of gastro intestinal contents, crop, gizzard, provenriculus, small intestine, caecum, and rectum were determined. Live weight loss was significantly (p<0.05) increased as length of feed withdrawal extended. A significant (p<0.05) carcass yield for both 1.5 and 2.5 kg groups coincided after 9 and 6 h feed withdrawal, respectively. Net weights of intestinal contents for crop and gizzard were significantly (p<0.05) reduced by 6 h, and the reduction for proventriculus and small intestine occurred from 3 h. A noticeable effect of feed withdrawal on pH for breast muscle at 3 h postmortem occurred only when chicks were fasted for 3 h of which pH (6.05) was significantly (p<0.05) higher than that for other groups including the control (5.74). There was a linear tendency of higher lightness (Hunter L* value) numerically for chicks fasted for longer periods. The highest coefficient of determinations of regression models to estimate weight loss as a function of fasting period and body weights were achieved, when the models included both linear and quadratic terms for fasting period, and linear term for both 1.5 ($R^2=0.76$) and 2.5 kg ($R^2=0.78$) body weight groups. Given the practical aspect, approximately 1.5 kg of body weight is dominant, weight loss could be predicted by the following function; live weight $loss=26.6-0.28{\times}(fasting period)^2+12.34{\times}pasting\;period-0.012{\times}body\;weight$, $R^2=0.76$. Current data implied that the optimum fasting time for pre-slaughter chicks varied depending on slaughter weight; 6 and 9-h fasting were recommendable for 2.5 and 1.5 kg chicks, with little effect on objective meat color.

• Molecules and Cells
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• v.43 no.11
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• pp.909-920
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• 2020

Cytosolic Ca²⁺ levels ([Ca²⁺]_c) change dynamically in response to inducers, repressors, and physiological conditions, and aberrant [Ca²⁺]_c concentration regulation is associated with cancer, heart failure, and diabetes. Therefore, [Ca²⁺]_c is considered as a good indicator of physiological and pathological cellular responses, and is a crucial biomarker for drug discovery. A genetically encoded calcium indicator (GECI) was recently developed to measure [Ca²⁺]_c in single cells and animal models. GECI have some advantages over chemically synthesized indicators, although they also have some drawbacks such as poor signal-to-noise ratio (SNR), low positive signal, delayed response, artifactual responses due to protein overexpression, and expensive detection equipment. Here, we developed an indicator based on interactions between Ca²⁺-loaded calmodulin and target proteins, and generated an innovative GECI sensor using split nano-luciferase (Nluc) fragments to detect changes in [Ca²⁺]_c. Stimulation-dependent luciferase activities were optimized by combining large and small subunits of Nluc binary technology (NanoBiT, LgBiT:SmBiT) fusion proteins and regulating the receptor expression levels. We constructed the binary [Ca²⁺]_c sensors using a multicistronic expression system in a single vector linked via the internal ribosome entry site (IRES), and examined the detection efficiencies. Promoter optimization studies indicated that promoter-dependent protein expression levels were crucial to optimize SNR and sensitivity. This novel [Ca²⁺]_c assay has high SNR and sensitivity, is easy to use, suitable for high-throughput assays, and may be useful to detect [Ca²⁺]_c in single cells and animal models.

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.707-717
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• 2018

Leukocytes are reportedly the first line of the innate immune defense and essential for the control of common bacterial infections. Therefore, in this work, the antibacterial activity of crocodile leukocyte extract against Propionibacterium acnes was evaluated, and we also characterized the related activity of skin infection. The leukocyte extract showed the minimum inhibitory concentration to be $100{\mu}g/ml$ to P. acnes. SEM imaging demonstrated that the leukocyte extract adversely affected P. acnes cell permeability in a concentration-dependent manner. Furthermore, the crocodile leukocyte extract could significantly reduce proinflammatory markers and decrease inflammatory signs in infected mouse ears. The crude leukocyte extract was further purified using FPLC and RP-HPLC. The resulting fraction F5 was indicated as the anti-acne peptide-containing fraction. The molecular mass of the peptide contained in F5 was calculated to be 4,790.5 Da. N-Terminal sequencing revealed the amino acid sequence as GPEPVPAIYQ, which displays similarities to immunoglobulin A and leucine-rich repeat neuronal protein. This is the first reported amino acid sequence of a crocodile leukocyte extract that possesses anti-acne activity. To attempt to use it in a prototype cosmetic, an anti-acne gel containing crude crocodile leukocyte extract was formulated, resulting in seven gel formulations (G1, G2, G3, G4, G5, G6, and G7). The formulations G5, G6, and G7 exhibited 2-fold higher anti-acne activity than G1-G4. Investigation of accelerating stability studies of anti-acne gel formulations G5, G6, and G7 demonstrated that a low storage temperature ($4^{\circ}C$) is suitable for maintaining the physical properties and biological activity of the anti-acne gel products.

• Journal of Animal Environmental Science
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• v.14 no.1
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• pp.61-68
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• 2008

The roof structural model of liquid manure storage tank was designed to improve a structural safety and an ability of resistance to corrosion by the bad environmental condition with high humidity and high gas concentration. Due to corrosion of a general steel, the 5 years used materials were reduced to one-third of a new material in the result of a bending strength test. Some structural materials were tested to evaluate a strength and an anti-corrosion, and stainless steel pipe (STS439), steel angle with zinc hot dipping, rectangular steel pipe covered with FRP (Fiberglass Reinforced Plastics) resin were selected finally. A stainless steel is more expansive about $3{\sim}5$ times than general structural steel. But its durability under heavy corrosive environment is expected twice as long as general steel. The roof models were designed as closed cone type for each of the three structural materials. In the result of a FEM (Finite Element Method) structural analysis for the developed models, the safe snow depth was higher 2.3 times than a general roof structure, when elements of equal section modulus were used.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.115-121
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• 2011

The objective of this study was to develop models to predict freshness factors (total viable counts (TVC), pH, volatile basic nitrogen (VBN), trimethylamine (TMA), and thiobarbituric acid (TBA) values) and the storage period in beef using a visible and near-infrared (NIR) spectroscopic technique. A total of 216 beef spectra were collected during the storage period from 0 to 14 d at a $10^{\circ}C$ storage. A spectrophotometer was used to measure reflectance spectra from beef samples, and beef freshness spectra were divided into a calibration set and a validation set. Multi-linear regression (MLR) models using the stepwise method were developed to predict the factors. The MLR results showed that beef freshness had a good correlation between the predicted and measured factors using the selected wavelength. The correlation of determination ($r^2$), standard error of prediction (SEP), and ratio of standard deviation to SEP (RPD) of the prediction set for TVC was 0.74, 0.64, and 2.75 Log CFU/$cm^2$, respectively. The $r^2$, SEP, and RPD values for pH were 0.43, 0.10, and 1.10; those for VBN were 0.73, 1.45, and 2.00 mg%; those for TMA were 0.70, 0.19, and 2.58 mg%; those for TBA values were 0.73, 0.13, and 2.77 mg MA/kg; and those for storage period were 0.77, 1.94, and 2.53 d, respectively. The results indicate that visible and NIR spectroscopy can predict beef freshness during storage.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2008.04a
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• pp.5-20
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• 2008

GLP-1-based drugs (GLP-1 analogues and DPP IV inhibitors) and incretin mimetics are currently one of the most exciting classes of agents for type II diabetes. GLP-1, a gut peptide, is an incretin that potentiates glucose-dependent insulin release from the pancreas, slows GI-transit and stimulates the proliferation of beta-cells. DPP IV inhibitors act like incretins by inhibiting DPP IV which inactivates GLP-1. LC15-0133 is a competitive, reversible DPP IV inhibitor ($IC_{50}$ = 24 nM, Ki=0.247 nM) with excellent selectivity over other critical human proteases such as DPP II, DPP 8, elastase, trypsin. and urokinase. LC15-0133 showed long half-life and good bioavailability in rats and dogs. Inhibition of plasma DPP IV activity by LC15-0133 was kept more than 50% 24 hours after oral dosing in rats and dogs at 0.1 mg/kg and 0.02 mg/kg, respectively. The Minimum effective doses of LC15-0133 were 0.01 mg/kg for lowering blood glucose excursion during oral glucose tolerance test and 0.1 mg/kg for increasing glucose-induced GLP-1 response in C57BL/6 mice. Repeat oral administration of LC15-0133 for 1 month delayed the progression to diabetes and reduced HbA1c levels in a dose-dependent manner in Zucker Diabetic Fatty rats. In conclusion, LC15-0133 is a novel, potent, selective and orally active DPP IV inhibitor and showed an excellent blood glucose lowering effects in various animal models.