• Journal of the Korean Physical Society
• /
• v.73 no.11
• /
• pp.1764-1773
• /
• 2018

A-PET is a quad-head PET scanner developed for use in small-animal imaging. The dimensions of its volumetric field of view (FOV) are $46.1{\times}46.1{\times}46.1mm^3$ and the gap between the detector modules has been minimized in order to provide a highly sensitive system. However, such a small FOV together with the quad-head geometry causes image quality degradation. The main factor related to image degradation for the quad-head PET is the mispositioning of events caused by the penetration effect in the detector. In this paper, we propose a precise method for modelling the system at the high spatial resolution of the A-PET using a LOR (line of response) based ML-EM (maximum likelihood expectation maximization) that allows for penetration effects. The proposed system model provides the detection probability of every possible ray-path via crystal sampling methods. For the ray-path sampling, the sub-LORs are defined by connecting the sampling points of the crystal pair. We incorporate the detection probability of each sub-LOR into the model by calculating the penetration effect. For comparison, we used a standard LOR-based model and a Monte Carlo-based modeling approach, and evaluated the reconstructed images using both the National Electrical Manufacturers Association NU 4-2008 standards and the Geant4 Application for Tomographic Emission simulation toolkit (GATE). An average full width at half maximum (FWHM) at different locations of 1.77 mm and 1.79 mm are obtained using the proposed system model and standard LOR system model, which does not include penetration effects, respectively. The standard deviation of the uniform region in the NEMA image quality phantom is 2.14% for the proposed method and 14.3% for the LOR system model, indicating that the proposed model out-performs the standard LOR-based model.

• Journal of Biomedical Engineering Research
• /
• v.42 no.1
• /
• pp.25-30
• /
• 2021

Objective: The aim of this study is to consider the effect of skin tissue necrosis by improving blood flow in animal skin models for low frequency pulsed electromagnetic fields (LF_PEMF) stimulation. Methods: Twenty rats (Wistar EPM-1 male, 280-320 g) were randomly divided into control groups (n=10) and the PEMF groups (n=10). To induce necrosis of the skin tissue, skin flap was treated in the back of the rat, followed by isolation film and skin flap suturing. Subsequently, the degree of necrosis of the skin tissue was observed for 7 days. The control group did not perform any stimulation after the procedure. For the PEMF group, LF_PEMF (1 Hz, 10 mT) was stimulated in the skin flap area, for 30 minutes a day and 7 days. Cross-polarization images were acquired at the site and skin tissue necrosis patterns were analyzed. Results: In the control group, skin tissue necrosis progressed rapidly over time. In the PEMF group, skin tissue necrosis was slower than the control group. In particular, no further skin tissue necrosis progress on the day 6. Over time, a statistically significant difference from the continuous necrosis progression pattern in the control group was identified (p<0.05). Conclusions: It was confirmed that low frequency pulsed electromagnetic fields (LF_PEMF) stimulation can induce relaxation of skin tissue necrosis.

• Journal of Biomedical Engineering Research
• /
• v.42 no.3
• /
• pp.94-99
• /
• 2021

Atopic dermatitis (AD), a chronic inflammatory skin disease, is characterized by itchy and age-dependent lesions. Previous studies have shown that pulsed electromagnetic field (PEMF) significantly improved chronic ulcers and ununited fractures, providing an evidence for the application of PEMF in resolving inflammation caused by AD. This study investigated the anti-inflammatory effect of PEMF on DNCB-induced AD in animal models. Five male hairless mice (6 weeks old) per group were assigned to a normal group, a sham group, and two PEMF groups (15Hz, 75Hz). Mice were treated with 2,4-Dinitrochlorobenzene (DNCB) to induce uniform AD among all groups excluding a normal group. To examine the inflammatory progress and the improvement of AD after the PEMF stimulation, images are taken with various cameras for non-invasive evaluation and the results are expressed using principal component analysis (PCA) for visualization. The results of this study demonstrated that PEMF effectively improved skin lesions without the use of drugs.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.34 no.5
• /
• pp.245-254
• /
• 2020

The purpose of this study was to investigate the effects of natural herb mixture containing Laminaria japonica Areschoung (LAM) on fine dust-induced bronchitis in mice. Laminaria japonica Areschoung is main content of LAM, which is including fucoidan. Fucoidan extracted from phaophyta is known to prevent bronchitis and to defend against bacteria and virus infection. In this study, we experienced the effect of LAM on bronchitis and investigated gene expressions (e.g ; IL-8, COX-2, MCP-1) and bio-markers (e.g ; IL-8, PGE2, MUC5AC) associated with bronchitis by using A549 cells. Also, we investigated whether LAM can suppress the bronchitis in fine dust-induced animal models. We injected fine dust (50 ㎕) twice as INT (Intra-Nasal-Trachea) method. Then LAM (200 mg/kg and 400 mg/kg) were oral administered for 14 days. We analyzed the number of immune cells, immunoglobulin E, bio-markers level associated with bronchitis. LAM significantly decreased bio-marker (IL-1β, IL-6, IL-8, TNF-α, Histamine, PGE2), immune cells (white blood cell, neutrophil, lymphocyte, monocyte), and immunoglobulin E, that are increased by fine dust. Taken together, this study suggest that LAM can be used as effective herbal extract for bronchitis.

• Electronics and Telecommunications Trends
• /
• v.36 no.1
• /
• pp.54-63
• /
• 2021

Since the recent COVID-19 pandemic, countries have been strengthening trade protection for their security, and the importance of securing strategic materials, such as food, is drawing attention. In addition to the cultural aspects, the global preference for food produced in Korea is increasing because of the Korean Wave. Thus, the Korean food industry can be developed into a high-value-added export food industry. Currently, Korea has a low self-sufficiency rate for foodstuffs apart from rice. Korea also suffers from problems arising from population decline, aging, rapid climate change, and various animal and plant diseases. It is necessary to develop technologies that can overcome the production structures highly dependent on the outside world of food and foster them into export-type system industries. The global agricultural industry-related technologies are actively being modified via data accumulation, e.g., environmental data, production information, and distribution and consumption information in climate and production facilities, and by actively expanding the introduction of the latest information and communication technologies such as big data and artificial intelligence. However, long-term research and investment should precede the field of living organisms. Compared to other industries, it is necessary to overcome poor production and labor environment investment efficiency in the food industry with respect to the production cost, equipment postmanagement, development tailored to the eye level of field workers, and service models suitable for production facilities of various sizes. This paper discusses the flow of domestic and international technologies that form the core issues of the site centered on the 4th Industrial Revolution in the field of agriculture, livestock, and fisheries. It also explains the environmental awareness production technologies centered on sustainable intelligence platforms that link climate change responses, optimization of energy costs, and mass production for unmanned production, distribution, and consumption using the unstructured data obtained based on detection and growth measurement data.

• The Korean Journal of Physiology and Pharmacology
• /
• v.26 no.1
• /
• pp.47-57
• /
• 2022

Stiripentol is an anti-epileptic drug for the treating of refractory status epilepticus. It has been reported that stiripentol can attenuate seizure severity and reduce seizure-induced neuronal damage in animal models of epilepsy. The objective of the present study was to investigate effects of post-treatment with stiripentol on cognitive deficit and neuronal damage in the cornu ammonis 1 (CA1) region of the hippocampus proper following transient ischemia in the forebrain of gerbils. To evaluate ischemia-induced cognitive impairments, passive avoidance test and 8-arm radial maze test were performed. It was found that post-treatment with stiripentol at 20 mg/kg, but not 10 or 15 mg/kg, reduced ischemia-induced memory impairment. Transient ischemia-induced neuronal death in the CA1 region was also significantly attenuated only by 20 mg/kg stiripentol treatment after transient ischemia. In addition, 20 mg/kg stiripentol treatment significantly decreased ischemia-induced astrocyte damage and immunoglobulin G leakage. In brief, stiripentol treatment after transient ischemia ameliorated transient ischemia-induced cognitive impairment in gerbils, showing that pyramidal neurons were protected and astrocyte damage and blood brain barrier leakage were significantly attenuated in the hippocampus. Results of this study suggest stiripentol can be developed as a candidate of therapeutic drug for ischemic stroke.

• Imaging Science in Dentistry
• /
• v.52 no.1
• /
• pp.61-66
• /
• 2022

Purpose: This study aimed to compare the therapeutic effects of corticosteroid irrigations and normal saline irrigations in the early inflammatory state of the salivary gland. Materials and Methods: Adult male Wistar rats were divided into experimental (n=6) and control (n=3) groups. Inflammation was induced in the experimental subjects on both sides of the submandibular gland with ligation. After 14 days, both sides of the glands were de-ligated and retroductal irrigation using saline (n=3) and a corticosteroid (n=3) was performed on the left sides only. The controls (n=3) were used to normalize the gland state for the effects of diet and aging. Magnetic resonance imaging was performed to confirm inflammation and post-irrigation gland recovery by measuring relative signal intensity (SI). The glands were excised for histological examination. Results: All experimental animals showed inflamed glands with increased SI and subsequent recovery of the gland with decreased SI to varying degrees. The SI of the controls showed no significant changes during the overall period. The mean SI change of the irrigated gland was higher than that of the non-irrigated side, without a significant difference. The corticosteroid-irrigated glands showed a greater change in SI than that of the saline-irrigated glands. Histology revealed that inflammation was not observed in most of the irrigated glands, while mild to moderate quantities inflammatory cells were found in non-irrigated glands. Conclusion: Corticosteroid irrigation mitigated the early stages of salivary gland inflammation more effectively than normal saline.

• Journal of Ginseng Research
• /
• v.46 no.1
• /
• pp.11-22
• /
• 2022

Spinal cord injury (SCI) is defined as damage to the spinal cord that temporarily or permanently changes its function. There is no definite treatment established for neurological complete injury patients. This study investigated the effect of ginseng extract and ginsenosides on neurological recovery and antioxidant efficacies in rat models following SCI and explore the appropriate dosage. Searches were done on PubMed, Embase, and Chinese databases, and animal studies matches the inclusion criteria were selected. Pair-wise meta-analysis and subgroup analysis were performed. Ten studies were included, and the overall methodological qualities were low quality. The result showed ginseng extract and ginsenosides significantly improve neurological function, through the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale (pooled MD = 4.40; 95% CI = 3.92 to 4.88; p < 0.00001), significantly decrease malondialdehyde (MDA) (n = 290; pooled MD = -2.19; 95% CI = -3.16 to 1.22; p < 0.0001) and increase superoxide dismutase (SOD) levels (n = 290; pooled MD = 2.14; 95% CI = 1.45 to 2.83; p < 0.00001). Both low (<25 mg/kg) and high dosage (25 mg/kg) showed significant improvement in the motor function recovery in SCI rats. Collectively, this review suggests ginseng extract and ginsenosides has a protective effect on SCI, with good safety and a clear mechanism of action and may be suitable for future clinical trials and applications.

• Journal of Veterinary Science
• /
• v.21 no.1
• /
• pp.9.1-9.15
• /
• 2020

Regenerative therapy holds great promise in the development of cures of some untreatable diseases such as cardiovascular diseases, and pluripotent stem cells (PSCs) including induced PSCs (iPSCs) are the most important regenerative seed cells. Recently, differentiation of human PSCs into functional tissues and cells in vitro has been widely reported. However, although porcine reports are rare they are quite essential, as the pig is an important animal model for the in vitro generation of human organs. In this study, we reprogramed porcine embryonic fibroblasts into porcine iPSCs (piPSCs), and differentiated them into cluster of differentiation 31 (CD31)-positive endothelial cells (ECs) (piPSC-derived ECs, piPS-ECs) using an optimized single-layer culture method. During differentiation, we observed that a combination of GSK3β inhibitor (CHIR99021) and bone morphogenetic protein 4 (BMP4) promoted mesodermal differentiation, resulting in higher proportions of CD31-positive cells than those from separate CHIR99021 or BMP4 treatment. Importantly, the piPS-ECs showed comparable morphological and functional properties to immortalized porcine aortic ECs, which are capable of taking up low-density lipoprotein and forming network structures on Matrigel. Our study, which is the first trial on a species other than human and mouse, has provided an optimized single-layer culture method for obtaining ECs from porcine PSCs. Our approach can be beneficial when evaluating autologous EC transplantation in pig models.

• The Korea Journal of Herbology
• /
• v.29 no.5
• /
• pp.55-63
• /
• 2014

Objectives : The purpose of this study was verification of the restoration ability effect of Danggwisusan extract(DG) in wound induced Rat. Methods : It needed to make a scar(around $2{\times}2cm^2$) on the top of the fascia in the back of the rats and then the rats were divided into 4groups(n=6). Control was not treated at all, where as DG was orally medicated DG, Terra was percutaneously applied Terramycin, and DG + Terra was both orally medicated DG and percutaneously applied Terramycin per day for three weeks. Results : 93% or higher cell viability was observed in all tested groups from 1, 10, $100{\mu}g/m{\ell}$ in RAW 264.7cells. The DG decreased NO and cytokine production activity dose dependently. The production of IL-$1{\beta}$, IL-6 and TNF-${\alpha}$ were decreased by 46%, 46% and 40% in DG treated $100{\mu}g/m{\ell}$. The size of wound was significantly decreasing in DG, Terra, DG + Terra. WBC was significantly reduced in DG and DG + Terra. Monocyte was significantly reduced in DG, Terra and DG + Terra. Neutrophil was also reduced in DG, DG + Terra but not meaningless. The mRNA expression of MMP-1 was significantly reduced in Terra, MMP-2 was significantly reduced in DG, Terra, DG + Terra, and MMP-9 was significantly reduced in DG + Terra. Conclusions : According to the results, we thought that DG showed anti-inflammatory activities on the RAW 264.7cells in mouse macrophage and in adult rat wound. Moreover, the progress of recovery was found visually, heamatologically, genetically and histopathologically. In conclusion, it could be thought that DG has effect on the treating of wound.