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        검색결과 480

        21.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To elucidate the effect of cellular phone electromagnetic wave (EMW) exposure on the developing cerebellar cortex of neonatal Sprague-Dawley rats, animals were exposed to cellular phone electromagnetic waves for 1 hr per day for 3 weeks. At the end of the experimental period, animals were sacrificed by cardiac perfusion, after which histological samples were prepared and observed microscopically. In the EMW exposure group, external granule cells were remained partially in the external granular layer without migrating into the internal granular layer. In addition, dark stained shrunken Purkinje cells with pyknotic nuclei increased and the outline of cells became irregular and showed degenerative signs, such as mitochondrial swelling and disrupted cristae. Moreover, the cisternae of rough endoplasmic reticula and Golgi complex were severely swollen. Bergmann glial cells adjacent to the dark stained Purkinje cells were swollen and cytoplasmic organelles were scant. Dark stained shrunken granule cells were also observed and the outline of cells was irregular. The results of the present study suggest that cellular phone EMW exposure to neonatal Sprague-Dawley rats leads to a partial delay of early migration of cerebellar cortical cells and degenerative changes in Purkinje cells, Bergmann glial cells and granule cells.
        4,000원
        23.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Dawley 계 숫컷 흰쥐(200∼210g)를 정상군, CCl4-대조군, CCl4-실험군으로 나누어 실험군은 갈근 에탄올 추출물을 1,000mg/kg,b.w의 용량으로 1일1회7일간 경구 투여 후 사염화탄소를 0.6mg/kg,b.w의 용량으로 복강내 주사 후 다음날 개복하여 혈청내의 Alanine aminotransferase(ALT), Aspartate aminotransferase(AST), Alkaline phosphatase(ALP), Glutamyltranspeptidase(γ-GT), Lactate dehydro-genase(LDH)의 활성도와 중성지방, 콜레스테롤 함량을 측정한 결과 갈근 추출물 투여 군에서 CCl4-대조군과 비교하여 유의적인 감소(p<0.05)를 나타내었으며, HDL-콜레스테롤은 유의적인 증가(P0.05)를 나타내었다. 간조직중의 지질과산화 함량과 Catalase(CAT),Glutathione peroxiddase (GSH-Px)의 항산화 효소 활성은 유의적인 감소를 나타내었다. 반면에 간 조직중의 glutathione 함량은 유의적인 증가를 나타내었다. 이 실험 결과 갈근 에탄올 추출물은 사염화탄소 투여에 의한 간 손상을 억제하는 보호물질과 항산화 물질을 함유하고 있음을 알 수 있었다.
        4,000원
        24.
        2017.06 구독 인증기관 무료, 개인회원 유료
        Recent studies indicate that mitochondria are an important source of reactive oxygen species (ROS) in the spinal dorsal horn. In our previous study, application of malate, a mitochondrial electron transport complex I substrate, induced a membrane depolarization, which was inhibited by pretreatment with ROS scavengers. In the present study, we used patch clamp recording in the substantia geletinosa (SG) neurons of spinal slices, to investigate the cellular mechanism of mitochondrial ROS on neuronal excitability. DNQX (an AMPA receptor antagonist) and AP5 (an NMDA receptor antagonist) decreased the malate-induced depolarization. In an external calcium free solution and addition of tetrodotoxin (TTX) for blockade of synaptic transmission, the malateinduced depolarization remained unchanged. In the presence of DNQX, AP5 and AP3 (a groupⅠ metabotropic glutamate receptor (mGluR) antagonist), glutamate depolarized the membrane potential, which was suppressed by PBN. However, oligomycin (a mitochondrial ATP synthase inhibitor) or PPADS (a P2 receptor inhibitor) did not affect the substrates-induced depolarization. These results suggest that mitochondrial substrate-induced ROS in SG neuron directly acts on the postsynaptic neuron, therefore increasing the ion influx via glutamate receptors.
        4,000원
        25.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Mesenchymal stem cells (MSCs) have been considered an alternative source of neuronal lineage cells, which are difficult to isolate from brain and expand in vitro. Previous studies have reported that MSCs expressing Nestin (Nestin+ MSCs), a neuronal stem/progenitor cell marker, exhibit increased transcriptional levels of neural development-related genes, indicating that Nestin+ MSCs may exert potential with neurogenic differentiation. Accordingly, we investigated the effects of the presence of Nestin+ MSCs in bone-marrow-derived primary cells (BMPCs) on enhanced neurogenic differentiation of BMPCs by identifying the presence of Nestin+ MSCs in uncultured and cultured BMPCs. The percentage of Nestin+ MSCs in BMPCs was measured per passage by double staining with Nestin and CD90, an MSC marker. The efficiency of neurogenic differentiation was compared among passages, revealing the highest and lowest yields of Nestin+ MSCs. The presence of Nestin+ MSCs was identified in BMPCs before in vitro culture, and the highest and lowest percentages of Nestin+ MSCs in BMPCs was observed at the third (P3) and fifth passages (P5). Moreover, significantly the higher efficiency of differentiation into neurons, oligodendrocyte precursor cells and astrocytes was detected in BMPCs at P3, compared with P5. In conclusion, these results demonstrate that neurogenic differentiation can be enhanced by increasing the proportion of Nestin+ MSCs in cultured BMPCs.
        4,000원
        26.
        2017.05 구독 인증기관·개인회원 무료
        Embryo transfer is one of the important process of assisted reproductive technology (ART) and that is associated with uterus endometrial receptivity. Recently, mouse endometrial stimulation by artificial injury had shown the favorable effect on conception. In this experiment, we used uterus stimulation method that injury the endometrium to increase implantation rate for spontaneous Diabetes Mellitus (sDM) rat. Rats are divided into several groups involved a control group. We performed the surgical method to Experimental group bilaterally or unilaterally After that, we investigated morphological change and calculated implanted embryos respective sides of the uterus. The number of implanted embryo in the experimental group was significantly higher and there were lots of morphological changes including glands and endometrial cells that support implantation. Our results showed that rat uterus endometrial injury in ART help enhancing implantation rate.
        27.
        2017.05 구독 인증기관·개인회원 무료
        Several species show low sensitivity to IVM, and the development of optimized medium possible oocyte quality and stable growth. Furthermore, adding additive to the medium can effectively reducing development cost and leads to easy handling of oocytes. Isoliquritigenin and formononetin are extracts found in licorice. Previous studies reported that isoliquritigenin and formononetin affected the activity of sperm, but the oocytes are unknown. This study adds isoliquritigenin or formononetin to αMEM to mature oocytes under simple IVC conditions. Recovered oocytes are cultured in αMEM, isoliquritigenincontaining medium and formononetin-containing medium. In study we proved that in addition to the medium, above the quality of oocytes cultured when specific additives were added, more stable growth is possible. collection and IVM of oocyte. SD rats at 6 to 8 wks of age are injected is intraperitoneal with 30 IU/mL of PMSG and 48 hrs later, HCG 50 IU/mL is intraperitoneal injected. Oocytes are collected ovary after 17 hrs. Collected oocytes are cultured for 16 hrs with 200 μL αMEM and 200 μL αMEM containing isoliquritigenin or formononetin at 0, 0.01, 0.02, 0.04, 0.1 mg/mL. Also, isoliquritigenin and formononetin were mixed with 200 μL αMEM at a ratio of 0.25: 0.75, 0.50: 0.50, and 0.75: 0.25 mg/mL respectively. Oocytes supplemented with isoliquritigenin and Formononetin had high quality than oocytes cultured with αMEM and showed an increase in the IVF fertility rate. Our experimental results indicate that using isoliquritigenin, formononetin when cell culture, rather than used only in medium, more effective oocyte quality and stable growth.
        28.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Free radicals originate due to the radiolysis of cytoplasmic water with low “Linear Energy Transfer” (LET) radiations. Naringenin (Ng) is a natural antioxidative compound found in citrus fruits. This study revealed that Naringenin (Ng) reduced the radiation damage of critical organs by scavenging oxidative free radicals. In the study, Ng was orally administrated to rats daily for 7 consecutive days, prior to whole body exposure to gamma-rays. The scavenging efficacy was evaluated biochemically by measuring the concentration of cytotoxic byproducts and the activity of enzymes relevant to oxidative free radicals, after extracting the organs from the exposed rat. We observed increased levels of malondialdehyde (MDA) concentration, and decrease in the activities of superoxide dismutase (SOD) and catalase (CAT) in the exposed control group. However, pretreatment with Ng significantly reduced the MDA concentration, and increased the activities of SOD and CAT, as compared to the control group, due to the free radical scavenging by Ng. The results indicate that Ng administration prior to irradiation could protect critical organs from radiation damage.
        4,000원
        29.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Lipoxygenase(LOX) 결핍 콩(05C4 및 LS, LOX2,3-free)과 일반콩(태광, LOX1,2,3-present)으로 제조된 된장의 급이가 고지방-콜레스테롤 식이성 흰쥐의 체내 지질성분 및 항산화 효소계에 미치는 영 향을 알아보고자 하였다. SD계 흰쥐는 정상군, 고지방-콜레스테롤 급이군(HFC), 고지방-콜레스테롤 식이+5% 된장 분말 급이군[HFC+D1, 태광된장; HFC+D2, 05C4된장; HFC+D3, LS된장)으로 구분하여 5주간 사육되었다. In vitro에서 된장의 콜레스테롤 흡착활성은 4mg/mL 농도에서 LS된장이 태광된장 에 비해 1.5배 높았다. 식이효율은 정상군에 비해 대조군에서 유의적으로 높았으며, LS된장 급이군 (HFC+D3)은 대조군에 비해 유의적으로 감소되는 경향이었다. Rö hrer 및 T.M.지수와 체지방 함량은 대조군에 비해 된장 급이군에서 모두 유의적으로 감소되었으며, 특히 Lee지수 및 BMI는 LOX 결핍콩 된장 급이군에서 유의적으로 감소되었다. 혈청 총 지질 및 중성지방 함량은 대조군에 비해 된장 급이군 에서 유의적으로 감소되었으나, 총 콜레스테롤, HDL-, LDL-콜레스테롤 및 심혈관질환 위험지수는 LS 된장 급이군만 유의적인 감소를 보였다. 혈청 AST 및 ALT 활성은 HFC+D1 및 HFC+D2간에는 유의차 가 없었고, HFC+D3은 HFC+D1 및 HFC+D2에 비해 유의적으로 낮은 수준이었다. 간 조직에서 총 지 질 함량은 HFC+D3이 대조군에 비해 약 25.2%의 감소되었으며(p<0.05), 중성지방 및 총 콜레스테롤 함량은 HFC+D2 및 HFC+D3이 대조군에 비해 유의적인 감소를 보였다. 분변 중의 중성지방 함량은 된 장 급이군 모두 대조군에 비해 26.2~40.3%의 증가를 보였으며(p<0.05), 총 콜레스테롤 함량은 LS된장 급이군만 유의적으로 증가하였다. 간 조직 중 SOD 활성은 대조군에 비해 05C4 및 LS된장 급이군에서 유의적으로 증가하였으며, catalase 및 GSH-px 활성은 된장 급이군 모두 대조군에 비해 유의적으로 증가하였다. UDPGT 활성은 된장의 급이 시 정상군과 유사한 수준으로 증가되었으며, 특히 LS된장 급 이군은 정상군에 비해 유의적으로 증가하였다. 따라서 LOX 결핍 콩으로 제조된 된장은 체내 지질 개선 및 항비만 활성에 긍정적인 도움이 될 것으로 판단된다.
        4,900원
        30.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to investigate the effects of low-intensity cardiac rehabilitation exercise on the cardiac function and the degree of fibrosis in an older white rat model. This study used male Sprague- Dawley white rats that were 50 weeks old. After the acute myocardial infarction induction, Twenty of the rats were randomly allocated into an experimental group and a control group, and each of the groups consisted of 8 rats. In the experimental group, the exercise was conducted for six weeks, 30 minutes a day, five days a week, using a Rotarod treadmill for animals. The degree of myocardial fibrosis was significantly repressed in the experimental group(13.69±1.90%) and in the control group(15.67±1.54%)(p<0.05). However, fractional shortening and ejection fraction did not show a significant difference. The results of this study suggest that cardiac rehabilitation with low intensity treadmill exercise repress the myocardial fibrosis.
        4,000원
        31.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        There is a growing interest in the application of primary hepatocytes for treatment of liver diseases in humans and for drug development. Several studies have focused on long-term survival and di-differentiation blocking of primary hepatocytes in an in vitro culture system. Therefore, the present study also aimed to optimize an in vitro culture system using primary rat hepatocytes. Primary rat hepatocytes from 6-week-old male Crl:CD rats were isolated using a modified two-step collagenase perfusion. Healthy 3.5 × 106 primary rat hepatocytes were seeded into a 2 dimensional (2D) culture in a 25T culture flask coated with collagen type I or into a 3D culture in a 125-ml spinner flask for 7 days. Production of plasma protein (ALB and TF), apoptosis (BAX and BCL2), and CYP (CYP3A1) related genes were compared between the 2D and 3D culture systems. The 3D culture system had an advantage over the 2D system because of the relatively high expression of ALB and low expression of BAX in the 3D system. However, the level of CYP3A1 did not improve in the 3D culture with and without the presence of a dexamethasone inducer. Therefore, 3D culture has an advantage for albumin production and primary rat hepatocyte survivability, but a low expression of CYP3A1 indicated that primary rat hepatocytes require a high–density culture for stress reduction by continuous flow.
        4,000원
        32.
        2016.06 구독 인증기관 무료, 개인회원 유료
        Tooth development shows dynamic morphological changes from the stages of cap to hard tissue formation and is strictly regulated during development. In the present study, we compared expression and localization of 3 major enamel matrix proteins in rats: amelogenin, enamel and ameloblastin. DD-PCR and RT-PCR revealed differential expression of the major proteins from the cap stage to root stage. Immunofluorescence staining results indicated that amelogenin was not detected in either inner enamel epithelium or reduced enamel epithelium, but highly immunoreactive in preameloblasts and ameloblasts; in addition, it was sporadically expressed in preodontoblasts abutting preameloblasts. Ameloblastin expression was also observed in not only differentiated ameloblasts but also osteoblasts. Immunoreactivity to ameloblastin in ameloblasts was strong in Tomes' processes. Enamelin was exclusively localized along the entire newly formed and maturing enamel. Enamelin was largely localized in near Tomes' processes and enamel rods in maturing enamel. Alendronate treatment resulted in down-regulation of amelogenin and ameloblastin at both transcription and translation levels; whereas, enamelin expression was unchanged in response to the treatment. These results suggested that amelogenin, ameloblastin and enamelin might be implicated in cell differentiation, adhesion of ameloblasts to enamel and enamel crystallization during enamel matrix formation, respectively.
        4,000원
        33.
        2016.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of the study was to investigate effects of Low intensity cardiac rehabilitation, using a treadmill, on the myocardial structure. We identified the effects by analyzing changes in the rats' weights and the results of biopsies. Twenty Sprague-Dawley male rats, 50 weeks old, were randomly divided into the exercise group and the control group. myocardial infarction( MI) was induced by ligaturing their left anterior descending artery. After the acute MI induction, two rats of each group began to fall dead, therefore, eight of each group completed at the end of the experiment. We used treadmills for animals for the exercise group. This exercise group performed 30 minutes of exercise five times per week for six weeks, while the control group did not perform any exercise. No statistically significant differences in weight were found in within group comparison and between group comparison. Furthermore, we observed histological changes in the myocardium using Hematoxylin & Eosin and Masson's trichrome staining in both groups. Low-intensity exercise inhibited myocardial fibrosis, may serve as a reference in the cardiopulmonary field, which plays a role in rehabilitating patients with cardiac disorders, including acute MI.
        4,000원
        34.
        2015.12 구독 인증기관 무료, 개인회원 유료
        Nitric Oxide (NO) is an important signaling molecule in the nociceptive process. Our previous study suggested that high concentrations of sodium nitroprusside (SNP), a NO donor, induce a membrane hyperpolarization and outward current through large conductances calcium-activated potassium (BKca) channels in substantia gelatinosa (SG) neurons. In this study, patch clamp recording in spinal slices was used to investigate the sources of Ca²+ that induces Ca²+-activated potassium currents. Application of SNP induced a membrane hyperpolarization, which was significantly inhibited by hemoglobin and 2-(4-carboxyphenyl) -4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide potassium salt (c-PTIO), NO scavengers. SNP-induced hyperpolarization was decreased in the presence of charybdotoxin, a selective BKCa channel blocker. In addition, SNP-induced response was significantly blocked by pretreatment of thapsigargin which can remove Ca²+ in endoplasmic reticulum, and decreased by pretreatment of dentrolene, a ryanodine receptors (RyR) blocker. These data suggested that NO induces a membrane hyperpolarization through BKca channels, which are activated by intracellular Ca²+ increase via activation of RyR of Ca²+ stores.
        4,000원
        35.
        2015.12 구독 인증기관 무료, 개인회원 유료
        Previous studies suggested that myelinated axons innervating rat molar pulps undergo morphological changes in their peripheral course. However, little information is available on the morphological feature of the parent axons at the site of origin. We therefore investigated the size of the myelinated parent axons and their morphological features at the proximal sensory root of the trigeminal ganglion by horseradish peroxidase (HRP) injection into rat upper molar pulps and subsequent light and electron microscopy. A total of 248 HRP-labeled myelinated axons investigated were highly variable in the size. Fiber area, fiber diameter, axon area (axoplasm area), axon diameter (axoplasm diameter), and myelin thickness were 11.32 ± 8.36 μm2 (0.80~53.17 μm2), 3.99 ± 1.53 μm (1.08~9.26 μm), 8.70 ± 6.30 μm2 (0.70~41.83 μm2), 3.13 ± 1.13 μm (0.94~7.20 μm) and 0.43 ± 0.23 μm (0.07~1.06 μm), respectively. The g-ratio (axon diameter / fiber diameter) of the labeled axons was 0.79 ± 0.05 (0.61~0.91). Axon diameter was highly correlated with myelin thickness (correlation coefficients, r=0.83) but little correlated with g-ratio (r=−0.33) of individual myelinated parent axons. These results indicate that myelin thickness of the myelinated parent axons innervating rat molar pulps increase with increasing axon diameter, thus maintaining a constant g-ratio.
        4,000원
        36.
        2015.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Probiotics is known improve the microenvironment of colon; however, the metagenomic DNA study of its lactic acid bacteria in constipation induced by loperamide is not clearly understood. In the present study, we investigated the reduction of the lactic acid bacteria in case of constipation, in normal and loperamide-induced rat. Lactic acid powder (lactic acid bacteria 19) was prepared from Chong Kun Dang Pharmaceutical Corporation. After 2 weeks of oral administration, the group treated with the higher concentration of lactic acid bacteria (109 CFU/mL per kg of body weight) following loperamide treatment was the most effective in increasing number, weight, and water content of feces. A similar but significant increase was found in the group treated with lower concentration of lactic acid bacteria (107 CFU/mL per kg of body weight) after loperamide treatment. The concentrations of acetic acid and propionic acid in feces in the loperamide-induced rat with high concentration lactic acid, were significantly higher than that of others. Furthermore, gastrointestinal transit ratio as well as the length and area of intestinal mucosa were significantly increased after treatment with lactic acid bacteria in loperamideinduced rat. Metagenomics DNA analysis indicated that the microorganism homology in cecum was similar between the groups of normal (NOR) and HIG. Our results show that lactic acid bacteria were effective in improving the constipation.
        4,000원
        38.
        2015.09 구독 인증기관 무료, 개인회원 유료
        The salivary gland undergoes complex process of growth and differentiation of the branching morphogenesis of ductal system during the prenatal and early postnatal periods which are regulated by various elements in the extracellular matrix. Extracellular matrix metalloproteinase inducer (EMMPRIN) is a cell adhesion molecule. In the present study, localization and expression of EMMPRIN in development and effects of chorda-lingual denervation and cyclosporine A (CsA) treatment on the EMMPRIN expression were investigated. Immunohistochemistry, RT-PCR and Western blot were used to determine expression level. Immunohistochemistry revealed that EMMPRIN was localized specifically in the cytoplasm of ductal cells, not acini of the submandibular gland all the postnatal periods. At prenatal day 18, when the formation of ducts was not definite, no immunoreactivity was observed. Both Western blot and RT-PCR analyses revealed that EMMPRIN expression was maintained up to postnatal day 7, decreased after postnatal day 10. The EMMPRIN expression was upregulated by the surgical denervation of the chorda-lingual nerve in the gland as well as by the CsA treatment. The present study suggests that EMMPRIN is a crucial molecule for maintaining physiological functions of the salivary gland.
        4,000원
        39.
        2015.08 구독 인증기관 무료, 개인회원 유료
        이 연구에서는 정소가 제거된 흰쥐에 비타민 E와 셀레늄(Selevit)을 5주간 투여 후 체중, 장기 무게, 혈액학적 그리고 생화학적 변화를 관찰하였다. 체중의 변화에서는 모든 실험군에서 증가가 나타냈다. Orch+Selevit군의 체중 증가는 11.2±10.25 g으로 가장 낮았으며, Intact군, Sham군, Orch군과 비교 시 유의적으로 감소되었다. 장기 무게의 변화에서는 Orch+Selevit군의 심장과 간장 무게는 Intact군, Sham군과 비교 시 유의적으로 감소되었다. Intact군, Sham군, Orch군의 신장 무게는 Orch+Selevit군 비교 시 유의적인 증가를 확인하였다. 백혈구 수의 혈액학적 변화에서는 Orch+Selevit군은 다른 모든 군과 비교해 유의적인 증가를 확인하였으며, 적혈구수, 평균적혈구용적, 평균적혈구혈색소량, 평균적혈구색소농도 등과 같은 혈액학적 측정치에서는 유의성은 인정되지 않았다. 생화학적 변화에서는 Orch+Selevit군의 혈청총단백질, 알부민은 Orch군과 비교 시 유의적으로 증가하였으며, 알부민은 Intact군, Sham군 그리고 Orch군과 비교 시 유의적으로 감소했다. AST와 ALT는 모든 실험군에서 유의성이 없었다.
        4,000원
        40.
        2015.06 구독 인증기관 무료, 개인회원 유료
        Growing evidence suggests that mitochondrial reactive oxygen species (ROS) are involved in various pain states. This study was performed to investigate whether ROS-induced changes in neuronal excitability in trigeminal subnucleus caudalis are related to ROS generation in mitochondria. Confocal scanning laser microscopy was used to measure ROS-induced fluorescence intensity in live rat trigeminal caudalis slices. The ROS level increased during the perfusion of malate, a mitochondrial substrate, after loading of 2′,7′-dichlorofluorescin diacetate (H2DCF-DA), an indicator of the intracellular ROS; the ROS level recovered to the control condition after washout. When pre-treated with phenyl N-tert-butylnitrone (PBN) and 4-hydroxy-2,2,6,6-tetramethylpiperidene-1-oxyl (TEMPOL), malate-induced increase of ROS level was suppressed. To identify the direct relation between elevated ROS levels and mitochondria, we applied the malate after double-loading of H2DCF-DA and chloromethyl-X-rosamine (CMXRos; MitoTracker Red), which is a mitochondria- specific fluorescent probe. As a result, increase of both intracellular ROS and mitochondrial ROS were observed simultaneously. This study demonstrated that elevated ROS in trigeminal subnucleus caudalis neuron can be induced through mitochondrial-ROS pathway, primarily by the leakage of ROS from the mitochondrial electron transport chain.
        4,000원
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