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        검색결과 15

        1.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Toll-like receptor 4 (TLR4) is known to contribute to the modulation of insulin resistance and systemic inflammation seen in obesity and the metabolic syndrome. The present study was performed to investigate the fertility competence of TLR4 knock out male mice (TLR4 mice) on a high-fat diet (HFD), compared to a normal-chow diet (NCD). The controls included wildtype (WT) mice fed on a HFD or NCD. Six-week-old male mice were fed with either a NCD or HFD for 20 weeks. Body and organ weights, serum levels of glucose, triglycerides and hepatoxicity, sperm quality and spermatogenesis were observed after the sacrifice. Also, randomly selected male mice were mated with virgin female mice after feeding of 19 weeks. The weight of the body and organs increased in WT and TLR4 mice on a HFD compared to those of mice on a NCD. The weights of the reproductive organs did not vary among the treatment groups. The motility and concentration of the epididymal spermatozoa decreased in both WT and TLR4 mice fed a HFD. The pregnancy rate and litter size declined in the HFD-fed WT mice compared to the HFD-fed TLR4 mice. In conclusion, the HFD alters energy and steroid metabolism in mice, which may lead to male reproductive disorders. However, fertility competence was somewhat restored in HFD-fed TLR4 male mice, suggesting that the TLR4 is involved in testis dysfunction due to metabolic imbalance.
        4,300원
        2.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Sirtuin 1 (SIRT1), the most conserved nicotinamide adenine dinucleotide-dependent protein deacetylase, is involved in the regulation of energy metabolism, genomic stability, and development. SIRT1 knockout (SIRT1) mice exhibit decreased energy expenditure and hypersensitivity to a high-fat diet (HFD). SIRT1 deficiency in the testis has also been shown to cause male infertility in animal models. Therefore, the present study was conducted to examine the alteration of the testicular function of SIRT1 mice on HFD. Six-week-old mice were fed ad libitum as wild type (WT) and SIRT1 male mice with either a control diet or with HFD for 32 weeks and then were sacrificed. The levels of biomarkers for hepatotoxicity, sex hormones, and cytokines were analyzed in the serum and blood-testis barrier, and the sperm morphology was examined in the testis and epididymal spermatozoa. Interestingly, an enlargement of seminal vesicles was observed in the SIRT1 mice fed with HFD. A significantly higher level of hepatotoxicity was also seen in these mice. The concentration of serum testosterone increased in HFD-fed SIRT1 mice compared to the controls. The levels of interleukin-1β and TNF-α increased in both HFD-fed WT and SIRT1 mice. In RT-PCR, the m RNA expression of tight junction protein 2 and claudin 3 significantly decreased in HFD-fed SIRT1 compared to those of the controls. Degenerative spermatocytes and spermatids were detected in the HFD-fed SIRT1 mice testicular section. Sperm motility decreased in WT and SIRT1 with HFD feeding, and sperm concentration decreased significantly in WT-HFD and SIRT1 mice with or without HFD feeding. Taken together, HFD can alter energy and steroid metabolism in SIRT1-deficient mice, which can lead to imbalances in motility and production of sperm and testosterone that can result in male reproductive disorders.
        4,300원
        3.
        2021.06 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Aluminum (Al) is one of the most widely applied metals in various industries. Anthropogenic activities of industrial waste result in increased accumulation of Al in natural water resources and aqueous organisms, leading to increased heavy metal pollution in the environment. This will ultimately associate with health risks to all living beings including humans. The present study addresses the possible toxic effects of Al on the motility and regeneration of planarians, using Dugesia japonica as the experimental animal model. Planarians were exposed to varying concentrations of Al (50–1,200 mg/L) for 1 hr, and subsequently evaluated for their motility, seizure-like behaviors, regeneration and alterations of the cell-organelles in their body. Results of the study exhibit that increasing Al concentrations lead to decreased motility and increased seizure-like behaviors, especially the c-type and head bob behaviors in planarians (p<0.05). The regeneration ability in the tail segments was reduced by increased Al concentrations, and the eyespot and optic nerves were more clearly observed in the control groups than planarians exposed to Al. Organelle analysis revealed morphological abnormalities in the mitochondria, golgi apparatus, endoplasmic reticulum, and cilia in the head region of planarians, as compared to the control groups. Taken together, our results indicate that exposure to Al alters the behavior of planarians and delays the regeneration of amputated body parts. Therefore, we suggest that Al exposure adversely can affect the lives of aquatic organisms, and induce toxicity such as cell abnormalities in animals.
        4,000원
        4.
        2021.06 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Lead (Pb) is a major heavy metal that augments environmental pollution and is a health risk to living organisms. This study was performed to investigate the effect of lead on characteristics of planarian, Dugesia japonica. Briefly, planarians were cultivated in water containing different concentrations (0–400 mg/L) of Pb, and incubated for varying durations (1, 3, and 5 hr). After termination of the incubation time, motility and seizure-like behaviors (c-like, head-bop, snake-like, and screw-like) of the planarians were counted in fresh water. Results showed that increasing Pb concentration and time resulted in decreased motility of the planarians (p<0.05). Increasing concentrations of Pb also resulted in significant increase in the seizure-like behavioral patterns, in particular the c-like and head-bop behaviors. In order to examine eye regeneration, the head region was cut, and rest of the body was incubated in water in the absence or presence of Pb, until emergence of the eye extrusion. Formation of eye spots was initiated in amputated fragments of the control group (without Pb) on day 4 after incubation, whereas appearance of the eye spots was delayed in planarian exposed to 200 mg/L Pb. Moreover, immunohistochemistry revealed that formation of the optic nerve was delayed in planarians exposed to Pb. Thus, our studies determined that planarians exposed to high concentrations of Pb resulted in decreasing motility and induction of seizure-like behaviors, as well as delayed eye regeneration. Results of the current study therefore validate that exposure to lead has a negative effect on the lifespan of aquatic organisms and can cause disturbance of the nervous system in animals, thereby implying the possibility of threatening health.
        4,000원
        5.
        2021.03 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        This study was undertaken to evaluate the toxic effect of cadmium sulfate (Cds) on planarians (Dugesia japonica), and the suitability of planarians as an alternative animal model for toxicity studies. Planarians were exposed to varying concentrations of experimental solutions containing 0.1–25 mg/L Cds, and incubated for 1, 3, and 5 hrs. Motility, seizure-like behaviors (c-like, head-bop, snake-like, and screw-like) and regeneration ability of the amputated fragment were subsequently evaluated. Results showed decreased motility with increasing concentrations of Cds (p<0.05), with the lowest motility being observed at the highest concentration of 25 mg/L Cds. Results also indicate that seizure-like behavior patterns were significantly affected by increments in the Cds concentrations, especially the c-like and head-bop behaviors were notably increased. Compared to the control, the regeneration ability of the planarians was decreased in the experimental solutions containing Cds. Planarians exposed to Cds showed either delayed eye formation or no eye regeneration during incubation. Moreover, increased concentrations of Cds resulted in failure to regenerate and death of the planarians. In conclusion, this study confirm that the heavy metal Cds exerts a toxic effect on planarians. Furthermore, the performances of the planarians in the experimental period exhibit their suitability as an alternative animal model for toxicity studies.
        4,000원
        6.
        2020.12 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Cyanobacteria (blue green algae) blooms formed in natural water resources due to the environmental pollution produce toxic compounds as secondary metabolites, causing health hazards to both humans and other living beings. Microcystin is a well-known toxin produced by cynobacteria. The present study was undertaken to evaluate varying concentrations and exposure times of two different forms of microcystin, viz., -LR (MCLR) and -LA (MCLA), on the motility and seizure-like behavior of planarian (Dugesia japonica). Compared to control, reduced motility was observed in both the MCLR or MCLA treated groups, but did not differ significantly with increasing concentrations of microcystin. However, the number of seizure-like behaviors were increased dose-dependently in planarian exposed to MLCR or MCLA. Exposure time to microcystine also affected the motility and seizure-like behaviors of planarians; 24 hrs incubation with MCLR, and 48 and 96 hrs exposure to MCLA, showed significantly (p<0.05) lower motility, as compared to the control. Assessing regeneration of the planarians revealed the simultaneous completion of eye formation at day 9 in planarians incubated in the absence or presence of MCLR or MCLA, thereby indicating that exposure to microcystin has no effect on the process. In conclusion, we determined that exposure to microcystins resulted in decrease in the number of motility, and induced abnormal behavior pattern in planarians. Further studies are required to identify the toxicity of microcystin that affects aquatic ecosystems.
        4,000원
        7.
        2019.06 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Nicotine is a component of tobacco products and is one of the most commonly abused substances that leads to addiction. Therefore, the present study was performed to investigate the behavioral pattern and toxicity by nicotine exposure in planarians. Basically, planarians were exposed to different concentration of nicotine for 5 min. To investigate detoxification effect, planarians were exposed to nicotine for 5 min, and treated glycyrrhizin for 5 min, then motility and seizure-like behavior were observed for 5 min. As a result, the motility of nicotine-exposed planarians decreased approximately more than 50% compared to freshwater control. However, the motility of glycyrrhizin-exposed planarians recovered than nicotineexposed planarians. In the assessment of seizure-like behavioral pattern, planarians exposed to nicotine showed head-bop or c-like type rather than screw-like or snake-like patterns. However, planarians exposed to glycyrrhizin showed no seizure-like behavior. To examine the oxidative stress response, planarians were cultured in fresh water containing 1 mM nicotine for 1 day. Planarians were homogenized and extracted to assay the contents of reactive oxygen species (ROS), lipid hydroperoxides (LH), glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). The result showed that a significantly higher level of ROS, LH indicated in planarians exposed to nicotine, on the other hand, glycyrrhizin-exposed planarians were significantly decreased ROS, LH levels. In conclusion, the motility decreased when planarians were exposed to nicotine, in a dose-dependent manner, whereas seizurelike behavior increased. Nicotine induced behavioral disturbances and cell toxicity in planarians were recovered by glycyrrhizin, suggesting a candidate substance for nicotine addiction treatment.
        4,000원
        8.
        2018.12 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        The objectives of this study were to find out the plant to enhance immune activity among 42 kinds of foods frequently consumed by the Korean elderly consisting of 5 food groups and 5 wild plants. Each sample was assessed the immunoactive effect by measuring NFkB/ AP1 gene expression, nitric oxide and cytokine production in RAW-Blue™ cell. Soybean sprouts of 47 plants showed the highest NF-κB/AP1 gene expression at the level of 1.13 ± 0.03 (O.D. 650 nm) and Soritae, sweet potato, banana, apple, garlic, crown daisy, cabbage and Ailanthus altissima also had high activity of NF-kB/AP1 gene in RAW-Blue™ cell stimulated by LPS. NO production of Ailanthus altissima was significantly higher than that of other plants and 16 plants of glutinous sorghum, black rice, Seoritae, Heuktae, sweet potato, banana, apple, garlic, mungbean sprouts, spinach, crown daisy, young pumpkin, cabbage, soybean sprouts, Actinidia arguta and Aster scaber were the next best activity. The above results selected 17 out of 47 plant samples. Moreover, soybean sprouts was significantly shown to increase TNF-α (1,509.55 ± 1.38 pg/mL) and IL-1β (54.56 ± 1.08 pg/mL) cytokines in comparison with RAW-Blue cell stimulated by LPS. According to the results of in vitro evaluation, the ethanol extract of soybean sprout increased the production of immune-enhancing cytokines by proliferation of macrophages. In addition, NF-kB transcription factor activity and NO production ability were excellent, and it was selected as a material having excellent immunological activity.
        4,200원
        9.
        2017.06 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Rubus coreanus is known to have diverse biological properties, such as free radical scavenging activity and antibacterial activity. In the present study, Rubus coreanus leaf and stem extract (RLSE) was used in boar semen preservation whether it has a beneficial effect on assisted reproductive technology (ART) in mammals. Boar spermatozoa were preserved in Beltsville thawing solution (BTS) in the presence of varying concentrations of RLSE (0-10 μg/mL). Sperm motility, sperm viability, and intracellular reactive oxygen species (ROS) levels were examined after 2 days of preservation. The percentage of total motile spermatozoa and progressive motile spermatozoa improved in the spermatozoa preserved with 0.5 μg/mL RLSE. Higher proportions of viable spermatozoa were seen in the presence of 0.5 and 1 μg/mL RLSE than in the control. Intracellular ROS levels decreased when the spermatozoa were preserved in BTS with 0.1–1 μg/mL RLSE. In order to examine the bacterial growth, E. coli was added to liquid semen diluted with antibiotics-free BTS in the presence or absence of RLSE. No anti-bacterial activity of RLSE against E. coli was observed during liquid semen preservation. Although there was no inhibition of E. coli growth, the addition of RLSE might help improve sperm motility and viability during boar semen preservation, suggesting it as a potential reagent for ART in mammals.
        4,000원
        10.
        2014.12 구독 인증기관 무료, 개인회원 유료
        Characteristics and immuno-modulatory effects of Enterococcus (E.) faecium JS1-8 isolated from Kimchi were investigated for potential probiotic use. We measured their acid, bile, and heat tolerances, adhesion properties in Caco-2 cells, antimicrobial activity against pathogenic bacteria, and bacteriocin-like substance-producing activity. Immuno-modulatory effects of E. faecium JS1-8 were measured by determination of nitric oxide (NO), nuclear factor-κB (NF-κB), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) production in RAW 264.7 cells or RAW BLUE cells. JS1-8 survived at pH 2.0 for 2 hr and showed tolerance to 0.3% oxgall bile salt, and it survived after exposure for 5 min at 80°C. JS1-8 showed high antimicrobial inhibition zones to Staphylococcus aureus (460 mm), Listeria monocytogenes (310 mm), Salmonella enteritidis (280 mm), and E. coli (150 mm). Bacteriocin-like substance produced by JS1-8 showed a broad spectrum of activity against Listeria monocytogenes KCCM 40307 and Lactobacillus sake KCCM 40264. Low concentration (1 × 107 CFU/mL) of heat-killed E. faecium JS1-8 induced statistically higher production of NO than Lactobacillus rhamnosus GG (LGG), which is a well-known immuno-modulatory lactic acid bacteria. Low and high (5 × 107 CFU/mL) concentrations of JS1-8 induced statistically higher production of NF-κB than that produced by LGG. We also found that JS1-8 increased production of pro-inflammatory cytokines such as IL-1β and TNF-α in a concentration-dependent manner. As a result, E. faecium JSI-8 could be used as a useful probiotic for controlling pathogens and enhancing host immune responses.
        4,000원
        11.
        2014.06 구독 인증기관 무료, 개인회원 유료
        The current study was conducted to evaluate the biocompatibility of α-1,3 galactosyltransferase knockout pig bone graft in a rat calvarial defect model. Porcine cancellous bones were harvested from general and alpha-gal KO pigs and washed with 70% ethanol solution and normal saline. Bone pieces of the alpha-gal KO pig underwent a chemical treatment process to delipidize and deproteinize the bone. Bone graft particles were freeze-dried and stored at −70°C until use. Each bone graft was implanted into the rat calvarial defect in a fresh general pig, fresh transgenic pig, and chemical-treated pig bone group. There was no systemic adverse effect on hematology or necropsy findings in all groups at 1 week and 4 weeks. In the microcomputed tomography analysis, bone volume increased significantly in the chemical-treated transgenic pig bone group, whereas bone mineral density decreased significantly in the fresh general pig bone group compared with other groups. Histological evaluation showed cellular infiltration located at the margin of the bone graft particles, especially in the fresh general pig bone group. These results indicate that fresh general pig bone can elicit a greater local inflammatory response than fresh transgenic pig bone. Further, chemical-treated transgenic pig bone graft was less immunogenic than fresh bone graft. In conclusion, transgenic pig bone is a more biocompatible graft material. In addition, chemical treatment can reduce bone graft immunogenicity by delipidizing and deproteinizing bone.
        4,000원
        12.
        2013.12 구독 인증기관 무료, 개인회원 유료
        In this study, characteristics and immuno-modulatory effects of Weissella cibaria JW15 isolated from Kimchi, traditional Korean fermented food, were examined for investigation of the capacity of potentially probiotic strains. We measured acid, bile, and heat tolerance, adhesive properties to intestinal epithelial cells, and inhibitory activity against pathogens. JW15 could survive at pH 3.0 for 2 hr, but not at pH 2.0. JW15 also showed tolerance to 0.3% oxgall bile salt, and heat tolerance at 70°C and 80°C for 5 min, respectively. Adhesive ability to Caco-2 cells was similar to that of Lactobacillus rhamnosus GG (LGG), a well-known commercial probiotic. JW15 exhibited antimicrobial activities to pathogenic bacteria such as Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, and Salmonella enteritidis. The immuno-modulatory effects of JW15 were compared with those of LGG, a well-known immune enhancer. For analysis, production of nitric oxide (NO), NF-κB (Nuclear factor κB), Interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) was measured. The concentration of NO induced by JW15 was higher than that by LGG at low concentration (1 × 107 cfu/mL). Low and high (5 × 107 CFU/mL) concentration of JW15 induced statistically higher production of NF-κB, IL-1β, and TNF-α than that produced by LGG, respectively. In conclusion, Weissella cibaria JW15 had ability as a probiotic strain, including acid, bile, and heat tolerance, adhesive properties to intestinal epithelial cells, and inhibitory activity against pathogens. In addition, JW15 showed better immuno-modulatory effects than LGG when NO, NF-κB, IL-1β, and TNF-α were measured. According to these results, the characteristics and immunomodulating activity of Weissella cibaria JW15 are suitable for consideration as a potential probiotic.
        4,000원
        13.
        2012.12 구독 인증기관 무료, 개인회원 유료
        Lactic acid bacteria (LAB) are known to promote activation of macrophages, selectively eliminate harmful intestinal bacteria that enter the body, and increase secretion of cytokines, chemokines, and inflammatory mediators that boost the immune system. In the current study, the immune-enhancing effects of five Leuconostoc stains (Leu. kimchii WK18, Leu. citreum DH33, Leu. mesenteroides DH34, SE34, and GY17) isolated from traditional Korean fermented food, Kimchi, were evaluated. Lactobacillus rhamnosus GG (LGG), which is known for its extraordinary immunopotentiating activity, was used as a reference strain. According to the results, several heat-killed Leuconostoc strains induced a higher level of NO, IL-1β, or TNF-α production than the LGG strain. Collectively, results of the current study suggest that Leuconostoc strains could enhance immune response through activation of macrophages, and could be significant references when verifying the possibility for use of Leuconostoc strains as probiotics, starter, dietary supplement, or immune-enhancing medicine.
        3,000원
        14.
        2009.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Dipterans are excellent insects to serve as forensic indicators to determine the postmortem interval of a human corpse. Therefore, we undertook a study to identify the major dipterans that are attracted to and develop in vertebrate carcasses. To determine what dipterans occur in Korea, chicken carcasses were placed in various habitats including the forest, open field, stream bank, greenhouse, rooftop, rice paddy, Chinese cabbage field, vacant hut, and pond at different times of the year. The dipterans were collected at various time intervals after placement in each habitat until the end of decomposition and identified. Our results showed that 49 identified and unidentified dipteran species from 36 genera in 19 families were collected from the carcasses. Habitat placement influenced the number of species isolated from the carcasses. For example, 39 species were collected from the forest habitat, 28 species from the open field, stream bank, or greenhouse each, 16 species from a vacant home, and 12 species from the pond. The dipteran species that were collected from all habitats were Phaenicia sericata, Lucilia illustris, and Lucilia sp. in the family Calliphoridae and Boettcherisca peregrine in the family Sarcophagidae. Other dipteran species that were isolated depended on carcass placement that is, fewer dipteran species were observed from carcasses in the backpack and much more species were recorded from unburied carcasses than buried carcasses. P. sericata, L. illustris, Lucilia sp., B. peregrine and an unidentified sarcophagid species were observed year round, but some dipterans showed seasonal differences.
        4,200원
        15.
        2015.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구에서 사용한 홍삼 전분은 홍삼 농축액 제조 공정에서 발생하는 부산물중 하나로 현재까지는 특별한 활용도가 없었다. 하지만 홍삼 농축액 제조 과정에서 발생되는 홍삼 유래의 물질로 홍삼의 유효 성분인 진세노사이드 및 각종 유리당, 탄수화물 등이 풍부한 안전한 소재로서의 가능성을 알아보고자 하였다. 홍삼전분을 이용한 새로운 홍삼막걸리의 차별화를 위하여 제품의 진세노사이드 함량, 유기산, 유리당, 효모수 등을 분석하였다. 효모 생균수의 변화 조사결과 4℃에서 저장하였을 때는 저장 20일까지 효모 균수에 큰 변화가 없었지만 25℃ 저장에서는 저장 20일에 초기 효모균수의 약 75%가 감소되었다. 유기산분석 결과 막걸리에서는 lactic acid가 4.16 mg/mL의 농도로 가장 많았으며, 그 다음으로는 citric acid 0.88 mg/mL, malic acid 0.39 mg/mL의 순서로 많았다. 저장 초기에는 malic acid의 함량이 4℃ 및 25℃에서 0.39 mg/mL 와 0.58 mg/mL 이었으나 저장일이 20일 경과하였을 때에는 0.46 mg/mL 그리고 0.17 mg/mL으로 측정되었고 대부분의 유기산은 저장기간에 관계없이 변화가 크게 나타나지 않았으나 butyric acid는 증가를 보였다. 20일 경에 lactic acid와 isobutyric acid는 감소하였으며 다른 종류의 유기산은 증가를 보였다. 유리당 분석결과 glucose가 4.4 mg/mL, sucrose 2.8 mg/mL 그리고 mannose 1.4 mg/mL 으로 막걸리의 주 구성당으로 분석되었으며 저장기간이 지속되면서 sucrose, glucose, mannose의 함량은 감소를 보여 알콜 발효의 주요 기질로 사용되었음을 보여주었다. 저장 4~8일 이후부터는 당이 급격히 감소하였으며 8일 이후부터는 큰 차이를 보이지 않았다. 이것은 저장 중 당분이 알콜과 탄산가스로 분해되었기 때문에 함량이 감소한 보여진다. 4℃에서 저장시, 일반적인 유통기간보다(10일) 긴 20일 동안 유리당의 변화를 보였으며 유리당은 12일 경에 sucrose, glucose와 mannose의 양은 1/2으로 감소하였다. 총산 및 pH 분석결과 각 저장온도에서 저장기간에 따른 pH의 변화는, 4℃에서 저장한 경우, 저장 4일경 pH 4.3에서 8일경 pH 3.8로 떨어지면서 저장기간 동안 서서히 감소되었다. 25℃에서 저장한 경우, pH 4.6~3.2 수준으로 4℃ 저장 온도보다 25℃ 온도에서 pH가 낮게 관찰 되었고 진세노사이드 분석결과 함량은 2.47 mg/g으로 측정되었다.