• The Korean Journal of Nuclear Medicine
• /
• 제28권2호
• /
• pp.177-185
• /
• 1994

Pharmacologic coronary vasodilation in conjunction with myocardial perfusion scintigraphy has become an alternative to dynamic exercise test for the diagnosis and risk stratification of coronary artery disease, especially in patients who are unable to perform adequate exercise. Dipyridamole and adenosine have been used for pharmacologic stress testing with myocardial perfusion imaging. Adenosine is a potent coronary vasodilator with rapid onset of action, short half-life, near maximal coronary vasodilation and less serious side effects. ST segment depression has been reported in about 7-15% of patients with coronary artery disease receiving dipyridamole in conjunction with myocardial perfusion imaging. The exact cause and clinical significance are not known. In order to evaluate the relationship between adenosine-induced ST segment depression during $^{99m}Tc$-MIBI myocardial perfusion scintigraphy and the severity of coronary artery disease, we performed $^{99m}Tc$-MIBI imaging after intravenous Infusion of adenosine In 120 patients with suspected coronary artery disease. Of the 120 patients, 28 also performed coronary angiography. There were 24 patients with ST segment depression during $^{99m}Tc$-MIBI scintigraphy and 96 patients without ST segment depression. Adenosine was infused Intravenously at a dose of 0.14mg/kg per minute lot 6minutes and $^{99m}Tc$-MIBI was injected at 3 minute. We then com-pared the hemodynamic changes, side effects, scintigraphic and angiographic findings. Heart rate increased $90{\pm}19$ beats/minute in the group with ST depression compared with $80{\pm}16$ beats/minute in the group without ST depression(p<0.05). Baseline systolic blood pressure was significantly higher in the group with ST depression($152{\pm}27$ mmHg) than in the group without 57 depression($140{\pm}21$mmHg, p<0.05). Double product at baseline($10.90{\pm}2.77$ versus $9.55{\pm}2.34\;beats/minute{\times}mmHg$) and during adenosine infusion($12.72{\pm}3.89$ versus $10.83{\pm}2.98\;beats/minute{\times}mmHg$) were significantly higher in the group with ST depression(p<0.05). The incidence of anginal chest pain was also significantly higher in the group with ST depression(ST versus 29%, p<0.0001). The $^{99m}Tc$-MIBI images were abnormal in 23(96%) patients with ST segment depression and 66(69%) patients without ST segment depression(p<0.05). In patients with ST segment depression, there were more reversible perfusion defects than in patients without ST segment depression(83 versus 55%, p<0.05). The number of abnormal segments were significantly higher in the group with ST depression($3.05{\pm}2.01$ versus $1.51{\pm}1.45$, p<0.005). In patients with ST segment depression, there were more segments of reversible perfusion defects than in patients without segment depression($2.15{\pm}2.11$ versus $0.89{\pm}1.24$, p<0.05). There were no differences in the angiographic severity by vessel(p ; NS). We concluded that ST segment depression during $^{99m}Tc$-MIBI myocardial perfusion scintigraphy with Intravenous adenosine is related to the severity of coronary artery disease.

• Journal of Life Science
• /
• 제14권4호
• /
• pp.650-656
• /
• 2004

Oryza grandiglumis (CCDD, 2n=48), one of the wild rice species, has been known to possess fungal-,bacterial-, and insect-resistance against sheath blight, rice blast, bacterial leaf blight and brown plant hopper (Nilaparvata lugens). To rapidly isolate differentially expressed genes responding to fungal and wounding stress, wounding and yeast extract were treated to O. grandiglumis for 24 hrs. Suppression subtractive hybridization (SSH) method was used to obtain differentially expressed genes from yeast extract and wounding treated plants. Seven hundreds and seventy six clones were obtained by subcloning PCR product, and colony array and screening were carried out using radio-isotope labeled cDNA probes prepared from the wounding and yeast extract treated plants. One hundred and fifteen colonies were confirmed as true positive ones. Average insert size of the clones were ranged from 400 bp to 700 bp and all the inserts were sequenced. To decide the identity of those clones, sequences were analyzed by sequence homology via GenBank database. The homology search result showed that 68 clones were matched to the genes with known function; 16 were related to primary metabolism, 5 to plant retrotransposons, 5 to defense related metallothionein-like genes. In addition to that, others were matched to various genes with known function in amino acid synthesis and processing, membrane transport, and signal transduction, so on. In northern blot analysis, induced expressions of ogwfi-161, ogwfi-646, ogwfi-663, and ogwfi-695 by wounding and yeast extract treatments were confirmed. The result indicates that SSH method is very efficient for rapid screening of differentially expressed genes.

• Korean Journal of Food Science and Technology
• /
• 제49권5호
• /
• pp.524-531
• /
• 2017

The study aimed to investigate the antioxidant activity and neuroprotective effect of the ethyl acetate fraction from Orostachys japonicus A. Berger extract (EFOJ) and its main constituent compounds. Among all fractions, the highest content of total phenolics was found in EFOJ. The antioxidant activity of EFOJ was confirmed through the 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 1-1-diphenyl-2-picryl-hydrazyl (DPPH), ferric reducing antioxidant power (FRAP) assays and the inhibitory effect of malondialdehyde (MDA). In addition, we ascertained that EFOJ not only decreased the intracellular ROS level, but also protected the neuronal cells against $H_2O_2$-induced oxidative stress. In liquid chromatography-mass spectrometry analysis, the following were found to be the main compounds of EFOJ: quercetin-3-O-glucoside, kaempferol-3-O-rutinoside, kaempferol-3-O-glucoside, and kaempferol-3-O-rhamnoside. Consequently, these results suggested that the protective effect on neuronal cells was based on the antioxidant activities of the physiologically active compounds of Orostachys japonicus A. Berger extract, which could therefore help to mitigate neurodegenerative diseases.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제27권5호
• /
• pp.373-384
• /
• 2001

Cellular proliferation is an intricately regulated process mediated by the coordinated interactions of critical growth control genes. Two of these factors in mammalian cells are the p53 and mdm-2 genes. A protein product of the mem-2 oncogene has been recently shown to associate with the protein encoded by the tumor suppressor gene p53. The p53 tumor suppressor protein is stabilized in response to DNA damage and other stress signals and causes the cell to undergo growth arrest or apoptosis, thus preventing the establishment of mutations in future cellular generations. Mutation or loss of p53 is a very common event in tumor progression. It occurs in about 50% of all tumors analysed including of colon, lung, breast and liver. The cellular mdm-2 gene, which has potential transforming activity that can be activated by overexpression, is amplified in a significant percentage of human sarcoma and in other mammalian tumors. Proteins encoded by the mdm-2 gene are able to bind to the p53 protein and, when overexpressed, can inhibit p53's transcriptional activation function, thus mdm-2 can act as a negative regulator of p53 function. Experimental study was performed to observe the relationship between p53 gene mutation and mdm-2 protein expression and apply the results to the clinical activity. 36 golden syrian hamster each weighing $60{\sim}80g$ were used and painted with 0.5% DMBA by 3 times weekly on the right buccal cheek(experimental side) for 6, 8, 10, 12, 14 and 16 weeks. Left buccal cheek(control side) was treated with mineral oil as the same manner to the right side. The hamsters were sacrificed on the 6, 8, 10, 12, 14 & 16 weeks. Normal and tumor tissues from paraffin block were examined for histology and immunohistochemistry observation, and were completely dissected by microdissection and DNA from both tissue were isolated by proteins K/phenol/chloroform extraction. Segments of the hamster p53 exons 5, 6, 7 and 8 were amplified by PCR using the oligonucleotide primers, and then confirmational change was observed by SSCP respectively. The results were as follows : 1. Dysplasia at 6 weeks, carcinoma in situ at 8 weeks and invasive carcinoma from 10 weeks could be observed in experimental groups. 2. p53 mutations were detected in 10 of the 36(28%) and the exons 6(6 of the 10 : 60%) was the most hot spot area among the highy conserved region(exons 5, 6, 7 & 8). 3. Immunohistochemical study confirmed 22 of the 36(61%) of p53 expression involving 10 of p53 mutations. 4. mdm-2 expression of was showed in 3 of the 36(8%) involving 1 of the 22 of p53 expression and 2 of the 14 of p53 non-expression. From the above results, mutation of p53 gene or expression of p53 protein may have the influence of the DMBA induced carcinoma of hamster buccal pouch but the expression of mdm-2 protein may not have relationship with tumorigenesis.

• Tuberculosis and Respiratory Diseases
• /
• 제63권6호
• /
• pp.497-506
• /
• 2007

Background: The present investigation was performed in rats and isolated human neutrophils in order to confirm the presumptive role of the positive feedback loop of cytosolic phospholipase $A_2$ ($cPLA_2$) activation by plateletactivating factor (PAF). Methods: The possible formation of the positive feedback loop of the $cPLA_2$ activation and neutrophilic respiratory burst was investigated in vivo and in vitro by measurement of the parameters denoting acute lung injury. In addition, morphological examinations and electron microscopic cytochemistry were performed for the detection of free radicals in the lung. Results: Five hours after intratracheal instillation of PAF ($5{\mu}g/rat$), the lung leak index, lung myeloperoxidase (MPO) activity, the number of neutrophils and the concentration of cytokine-induced neutrophil chemoattractant (CINC) in bronchoalveolar lavage fluid were increased by PAF as compared with those of control rats. The NBT assay and cytochrome-c reduction assay revealed an increased neutrophilic respiratory burst in isolated human neutrophils following exposure to PAF. Lung and neutrophilic $cPLA_2$ activity were increased following PAF exposure and exposure to hydrogen peroxide increased $cPLA_2$ activity in the lung. Histologically, inflammatory findings of the lung were observed after PAF treatment. Remarkably, as determined by $CeCl_3$ cytochemical electron microscopy, increased production of hydrogen peroxide was identified in the lung after PAF treatment. Conclusion: PAF mediates acute oxidative lung injury by the activation of $cPLA_2$, which may provoke the generation of free radicals in neutrophils.

• Journal of the East Asian Society of Dietary Life
• /
• 제24권6호
• /
• pp.759-767
• /
• 2014

This study examined the effect of Momordica charantia L. (bitter melon: BM) on lipid and hepatic antioxidative enzyme levels in diabetic rats. Diabetes mellitus was induced in male Sprague-Dawley rats by injection of streptozotocin (STZ), and rats were fed for 4 weeks with experimental groups divided into four groups: a normal control group, STZ-control and STZ-BM 5% & STZ-BM 10% treated groups. Levels of free fatty acids (FFA), high-density lipoprotein cholesterol (HDL-chol), triglycerides (TG) in plasma and malondialdehyde (MDA) & protein in liver, catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), and xanthine oxidase (XOD) were measured in liver cytosol. Level of HDL-chol significantly increased in the STZ-BM 5% diabetic group. TG & FFA levels were significantly higher in all diabetic groups compared to the control group. MDA and protein levels were significantly higher in the STZ-BM 5% group compared to all other experimental group. CAT level was higher in the supplementary group with BM compared to the STZ-control group, although the difference was not significantly different. SOD level was not significant in any experimental groups. GST level was significantly higher in the BM-treated groups compared to the STZ-control group. XOD level was significantly lower in the BM 5% group and significantly decreased in all experimental groups. These results show that supplementation of BM fruit powder may have beneficial effects on diabetic complications and damage caused by oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
• /
• 제32권2호
• /
• pp.278-286
• /
• 2003

Alcohol is well known agent which can damage the human tissues such as liver via stimulating lipid peroxidation. On the other hand, carotenoids in addition to vitamins A, C and I play important roles in protecting these oxidative damages as well as preventing the production of free radicals. This study was carried out to investigate the effect of dietary vitamin A on lipid peroxidation and antioxidants status in ethanol-treated rats. In the experiment, male Sprague-Dawley rats weighing 160~180 g were given a liquid diet containing 36% of total calories as ethanol for 7 weeks. The pair-fed control rats received an isocaloric amount of diet containing sucrose instead of ethanol on the following day Additionally, the liquid diet contained adequate amount of $\beta$-carotene, retinyl acetate or 13-sis-reinoic acid except vitamin A-deficient diet. The results obtained are as follows. The levels of plasma and hepatic lipid peroxide were increased after chronic ethanol feeding in rats. Retinyl acetate supplementation significantly reduced lipid peroxidation induced by ethanol feeding Glucose 6-phosphatase activity was significantly reduced in rats fed vitamin A-deficient diet with ethanol and alkaline phosphatase activity was significantly induced in rats fed 13-cis-reinoic acid diet with ethanol. Catalase and alcohol dehydrogenase activities did not show a consistent tendency in experiment groups. The hepatic antioxidant enzyme activities did not significantly changed by chronic ethanol feeding groups. The striking decrease in conversion of $\beta$-carotene to retinol was observed in rats fed a $\beta$-carotene diet with ethanol feeding The level of retinol and retinoic acid in plasma and liver was decreased after chronic ethanol administration Based on this result, these data suggest that ethanol feeding enhances oxidative stress especially in those fed a vitamin A-deficient diet, and vitamin A supplementation, especially, retinyl acetate intake can prevent enhanced lipid peroxidation and related damage to some extent.

• Korean Journal of Food Science and Technology
• /
• 제46권5호
• /
• pp.609-615
• /
• 2014

The cytoprotective effect of Moringa oleifera Lam. (drumstick tree) on neuronal cells was investigated to confirm the physiological benefits associated with this natural food resource. First, the drumstick tree extract was chemically analyzed to determine inherent nutritional constituents. Calcium and potassium were identified as the major mineral constituents, and palmitic acid (C16:0, 16.33%) and gadoleic acid (C20:01, 66.34%) were detected as the major fatty acids. Moreover, drumstick tree extract contained 94.78 mg/100 g vitamin E and 112.61 mg/100 g niacin. PC12 cells were used to study the cytoprotective effects of drumstick tree extract. Intracellular accumulation of reactive oxygen species was significantly reduced when $H_2O_2$ treated-neuronal cells were cultured in a medium containing the methanolic extract of drumstick tree, compared to cells treated with only $H_2O_2$. Cell viability assay using MTT showed that the extract protected cells against $H_2O_2$-induced neurotoxicity and inhibited LDH leakage from the cell membrane. Caspase assay showed that the extract exerted cytoprotective effect against apoptosis. Consequently, these data suggest that drumstick tree is a useful natural resource with positive effects on human health.

• Journal of Life Science
• /
• 제31권10호
• /
• pp.885-897
• /
• 2021

Schisandrae Fructus (SF) and Corni Fructus (CF) have been used for a long time for the prevention and treatment of various diseases. Although reports have highlighted the possibility of inhibiting the onset and progression of benign prostatic hyperplasia (BPH), studies on related mechanisms are still lacking. In this study, we investigated the potential of SF and CF in improving BPH by using a dihydrotestosterone (DHT)-induced in vitro BPH model using LNCaP prostate carcinoma cells. According to our results, water and ethanol extracts of SF and CF significantly inhibited the proliferation of LNCaP cells by DHT treatment and markedly downregulated the expression of DHT-induced BPH biomarkers and growth factors. They also regulated the expression of apoptosis regulatory factors and significantly reduced DHT-mediated oxidative stress. In addition, the protective effect on major factors involved in the pathogenesis of BPH was more effective in the ethanol extract treatment group than in the water extract group. Furthermore, the improvement effect on BPH was higher in the 1:1 combined treatment group than in the ethanol extract alone treatment group of SF and CF, and 60% ethanol extracts showed a better effect than 40% ethanol extracts. Therefore, our findings demonstrate that SF and CF can protect against BPH by preventing the hyperproliferation of prostate cells through the inhibition of the androgen signaling pathway, which was correlated with their antioxidant activities. Therefore, SF and CF extracts may be useful in the clinical treatment of BPH, and the combination of these two extracts can be synergistic.

• Journal of the Korean GEO-environmental Society
• /
• 제20권5호
• /
• pp.13-21
• /
• 2019

There are many cuts or natural rock slopes that remain stable for a long time in the natural environment with steep slopes ($65^{\circ}$ to $85^{\circ}$). In terms of design practice, the rock mass consisting of similar rock condition and geological structures is defined as a good continuum rock slope, and during the process of decision making angle of this rock slope, it will be important to establish the geotechnical properties estimating method of the continuum rock on the process of stability analysis in the early stages of design and construction. In this study, the stability analysis of a good continuum rock slope that can be designed as a steep slope proposed a practical method of estimating the shear strength by induced from the Hoek-Brown failure criterion, and in addition, the design applicability was evaluated through the stability analysis of steep rock slope. The existing method of estimating the shear strength was inadequate for practical use in the design, as the equivalent M-C shear strength corresponding to the H-B envelope changes sensitively, even with small variations in confining stress. To compensate for this problem, it was proposed to estimate equivalent M-C shear strength by iso-angle division method. To verify the design applicability of the iso-angle division method, the results of the safety factor and the displacement according to the change in angle of the cut slope constructed at the existing working design site were reviewed. The safety factor is FS=16~59 on the 1:0.5 slope, FS=12~52 on the 1:0.3 slope, most of which show a 10~12 percent reduction. Displacement is 0.126 to 0.975 mm on the 1:0.5 slope, 0.152 to 1.158 mm on the 1:0.3 slope, and represents an increase of 10 to 15%. This is a slightly change in normal proportion and is in good condition in terms of stability. In terms practical the working design, it was confirmed that applying the shear strength estimated by Iso-angle division method derived from the H-B failure criterion as a universal shear strength for a good continuum rock mass slope was also able to produce stable and economic results. The procedure for stability analysis using LEM (Limit Equilibrium Analysis Method) and FEM (Finite Element Analysis Method) will also be practical in the rock slope where is not distributed fault. The study was conducted by selecting the slope of study area as a good rock condition, establishing a verification for which it can be applied universal to a various rock conditions will be a research subject later on.