• Title/Summary/Keyword: Activity assay

Search Result 5,711, Processing Time 0.043 seconds

Exploration of Virulence Markers and Genes of Listeria monocytogenes Isolated from Animal Products (축산물유래 Listeria monocytogenes의 virulence marker 및 gene 조사)

  • Yi, Chul-Hyeon;Song, Hyeon-Ho;Kim, Mi-Ryung;Kang, Ho-Jo;Son, Won-Geun
    • Journal of Food Hygiene and Safety
    • /
    • v.23 no.3
    • /
    • pp.248-256
    • /
    • 2008
  • To investigate the epidemiological characteristics of 68 Listeria monocytogenes isolates, including 11 reference strains and 57 isolates from imported US beef, domestic meats(beef, pork, chicken meat), raw milk, and milk plants. L. monocytogenes was to evaluate the production of virulence proteins, such as hemolysin(LLO) and lecithinase(LCP), the adsorption of Congo red(CRA), and to detect virulence genes using the polymerase chain reaction(PCR). In the study of virulence protein production, 68(100%), 62(91.2%), and 54(79.4%) of the 68 L. monocytogenes strains were positive for LLO production, the LCP test, and the CRA test, respectively, while strains of other species, such as L. innocua, L. gray, L. murrayi, and L. welshimeri, were not. There were no significant differences between L. monocytogenes serotypes and the ability to produce LLO or LCP. L. monocytogenesstrains had very high hemolytic titers(2 to 16 fold), while the other Listeria species, other than L. ivanovii and L. seeligeri, did not. The hemolysin activities of L. monocytogenes, L. ivanovii, and L. seeligeri usually exceeded 1.0 HU/mg, while those of other Listeria spp. were less than 0.04 HU/mg. In the PCR assay, all of the L. monocytogenes strains contained the hlyA, plcA, plcB, inlA, and inlB virulence genes and produced a product of the expected size. In the PCR of the actA gene, the expected 385-bp product was seen in 39(57.4%) L. monocytogenesstrains, while an unexpected 268-bp product was seen in 29(42.6%) strains. Most L. monocytogenes strains isolated from Hanwoo beef produced the 385-bp actA gene product, while strains of imported US beef usually produced the 268-bp actA gene product. By contrast, no virulence gene products were amplified in the other Listeria spp.

Effect of Xanthine Oxidase Inhibitor on Cerebral Hypoxia-Ischemia in Neonatal Rats (Xanthine Oxidase Inhibitor가 저산소성-허혈성 뇌손상이 유도된 신생쥐에 미치는 영향)

  • Choi, Dae-Ho;Oh, Yeon-Kyun;Park, Seung-Tak
    • Clinical and Experimental Pediatrics
    • /
    • v.45 no.6
    • /
    • pp.732-742
    • /
    • 2002
  • Purpose : In order to evaluate the hypoxia-ischemia(H-I) induced neurotoxicity and the protective effect of xanthine oxidase(XO) inhibitor(allopurinol), cell number, cell viability, lactate dehydrogenase(LDH), protein synthesis(PS) and protein kinase C(PKC) activity were measured in cerebral neurons and astrocytes. Methods : Cytotoxic effect was measured by in vitro assay at 12-72 hours after H-I on cerebral neurons and astrocytes derived from 7-day old neonatal rats which were subjected to unilateral common carotid artery occlusion and exposed to hypoxic condition for 3 hours. The protective effect of XO inhibitor was examined by the cell number, cell viability, LDH and PS on 14 days after H-I with allopurinol intraperitoneal injection 15 minutes prior to H-I. In addition, the effect of allopurinol on PKC activity in hypoxic conditions was examined in neurons. Results : 72 hours from H-I, the cell numbers and viability were decreased significantly in time-dependent manner on neurons and those of astrocytes also decreased slightly, compared with control. In neonatal rats treated with H-I, the cell number, cell viability, and PS in neurons were decreased, but LDH was increased significantly compared with control. In neonatal rats pretreated with allopurinol, the cell number and viability, and PS in neurons were increased and LDH was decreased significantly compared with H-I. PKC was increased remarkably after hypoxic condition. But PKC was decreased significantly against hypoxic condition after allopurinol pretreatment. Conclusion : From these results, it is suggested that H-I is more toxic in neurons than astrocytes and allopurinol is very protective with increasing of PS, and decreasing of LDH and PKC in neurons from hypoxic-ischemic condition.

Protective Effect of Kefir Grain Against Dextran Sodium Sulfate-Induced Colitis in Rats (Dextran Sodium Sulfate로 대장염을 유도한 흰쥐에서 캐피어 원말의 장보호 효과)

  • Ko, Young-Eun;Kim, Mi-Kyoung;Cho, Han-Young;Lee, In-Young;Ly, Sun-Yung
    • Journal of Nutrition and Health
    • /
    • v.41 no.5
    • /
    • pp.391-401
    • /
    • 2008
  • Probiotics have emerged as a potential treatment modality for numerous gastrointestinal disorders, including IBD. However, few probiotics have undergone appropriate preclinical screening in vivo. Kefir is considered a probiotic, benefiting the host through its effects in the intestinal tract. Despite numerous studies examining the action of probiotics on the host organism, few have analyzed the effects on intestinal environment. We assessed the protective effect of kefir for three weeks before inducing colitis with 2% dextran sodium sulfate for five days. The DSS loads were similar in all DSS treatment group. The results of the experiment are as follows. Food intake and FER of experimental groups were not significantly different each other, but water consumption tended to be higher in all DSS treatment groups as compared with the normal control. And visual inspection of feces revealed mild diarrhea in rat given 2% DSS. The anti-inflammatory activity of kefir was determined by myeloperoxidase activity during the DSS treatment, and there was no significant difference in any group. The levels of thiobarbituric acid reactive substances (TBARS) as a colonic lipid peroxidation were significantly lower in the kefir intake groups than in rats treated with 2% DSS alone. The DNA % in tail and tail moment values as a DNA damage level of the blood lymphocytes in kefir intake groups tended to be lower than 2% DSS treatment alone, especially tail lengths were significantly diminished. According to the colonic histopathological assay, there were a severe inflammation of lamina propria and submucosa and mild edema in mucosa and sub mucosa in DSS alone treated group. We found a slight regenerative change in kefir treatment groups. In our experiments, this means that ulcerative colitis related to oxidative injury might be prevented by kefir as a probiotic. Further studies of the potential benefits of kefir as a probiotic in inflammatory condition are encouraged.

Antioxidant Activities of Ipomoea batatas L. Lam. (Purple Sweet Potato) Extracts Cultured in Korea (국내산 자색고구마(Ipomoea batatas L. Lam.) 추출물의 항산화활성 평가)

  • Kong, Bong Ju;Han, Sung Soo;Ha, Ji Hoon;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.40 no.4
    • /
    • pp.423-430
    • /
    • 2014
  • In this study, the antioxidative effects for the extracts of purple sweet potato (Ipomoea batatas L. Lam.) were investigated. The purple sweet potato was extracted with 70% ethanol and the ethyl acetate fraction was obtained from the extracts. The yields of extract and ethyl acetate fraction were 39.2% and 3.49% per dried powder, respectively. To confirm the antioxidative effects of the extracts, free radical scavenging activities (1,1-diphenyl-2-picrylhydrazyl), total antioxidant capacity by luminol-dependent chemiluminescence assay and the protective effects against reactive oxygen species (ROS) in erythrocytes were measured. Free radical scavenging activities ($FSC_{50}$) of the 70% ethanol extract and ethyl acetate fraction were $90.16{\mu}g/mL$ and $7.69{\mu}g/mL$, respectively. The free radical scavenging activity of ethyl acetate fraction was higher than that of (+)-${\alpha}$-tocopherol ($8.98{\mu}g/mL$). Total antioxidant capacities ($OSC_{50}$) of the 70% ethanol extract and ethyl acetate fraction were $5.75{\mu}g/mL$ and $1.92{\mu}g/mL$, respectively. The capacity of ethyl acetate fraction was similar to L-ascorbic acid, known as a prominent water soluble antioxidant ($1.50{\mu}g/mL$). The cellular protective effects of the ethyl acetate fractions on the $^1O_2$-induced cellular damage of human erythrocytes were increased in a concentration dependent manner ($5{\sim}50{\mu}g/mL$). The ${\tau}_{50}$ value in $5{\mu}g/mL$ was 45.6 min which was higher than that of (+)-${\alpha}$-tocopherol in all concentrations. These results indicate that the ethyl acetate fraction of purple sweet potato (I. batatas) has the excellent antioxidative capacity and could be applicable to anti-aging cosmeceutical ingredients for skin aging inhibition.

The Relationship between the Salivary IgA against AgI/II of S. mutans and Dental Caries Experience among Children and Adults (소아와 성인의 타액 내 AgI/II 특이 IgA 와 우식경험도의 관계)

  • Lim, Su-Min;Kim, Jae-Gon;Baik, Byeong-Ju;Yang, Yeon-Mi;Kim, Su-Kyung;Lee, Kyung-Yol
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.35 no.4
    • /
    • pp.671-676
    • /
    • 2008
  • AgI/II of Streptococcus mutans(S. mutans) is an important virulence factor that contributes to the pathogenesis of S. mutans-induced dental caries. In oral cavity, salivary IgA antibodies act as safeguards against enormous challenges from oral bacteria. IgA antibodies inhibit adherence of cariogenic microorganisms to hard surfaces. Analysis of salivary IgA against AgI/II can be very useful diagnostic and powerful communication tools to the dental caries The purpose of this study was to investigate correlation between salivary AgI/II specific IgA and incidence of dental caries among children and young adults. Subjects consisted of 28 children and 18 adults. They were assigned to four groups : Group I deft index $\leq$3), Group II(deft index $\geq$4), Group III(DMFT index $\leq$3), Group IV(DMFT index $\geq$4) and they was divided two groups into caries resistant group and caries susceptible group. The study group were examined caries activity and their salivary IgA was evaluated by enzyme-linked immunosorbent assay. The results are as follows : 1. There was a positive correlation between the number of S. mutans and caries activity. 2. The titer of salivary IgA against the AgI/II was significantly higher in caries resistant group than caries susceptible group(p<0.01). 3. The titer of salivary IgA against the AgI/II in Group III was significantly higher than Group II(p<0.05).

  • PDF

TNF-α in the Pleural Fluid for the Differential Diagnosis of Tuberculous and Malignant Effusion (결핵성 및 악성흉수의 감별에 있어 흉수 내 TNF-α의 유용성)

  • Kim, Hye Jin;Shin, Kyeong Cheol;Lee, Jae Woong;Kim, Kyu Jin;Hong, Yeong Hoon;Chung, Jin Hong;Lee, Kwan Ho
    • Tuberculosis and Respiratory Diseases
    • /
    • v.59 no.6
    • /
    • pp.625-630
    • /
    • 2005
  • Background : Determining the cause of an exudative pleural effusion is sometimes quite difficult, especially between malignant and tuberculous effusions. Twenty percent of effusions remain undiagnosed even after a complete diagnostic evaluation, including pleural biopsy. The activity of tumor necrosis factor-alpha (TNF-${\alpha}$), which is the one of proinflammatory cytokines, is increased in both infectious and malignant effusions. The aim of this study was to investigate the diagnostic efficiency of TNF-${\alpha}$ activity in distinguishing tuberculous from malignant effusions. Methods : 46 patients (13 with malignant pleural effusion, 33 with tuberculous pleural effusion) with exudative pleurisy were included. TNF-${\alpha}$ concentrations were measured in the pleural fluid and serum samples using an enzyme-linked immunosorbent assay (ELISA). In addition, TNF-${\alpha}$ ratio (pleural fluid TNF-${\alpha}$ : serum TNF-${\alpha}$) was calculated. Results : TNF-${\alpha}$ concentration and TNF-${\alpha}$ ratio in the pleural fluid were significantly higher in the tuberculous effusions than in the malignant effusions (p<0.05). However, the serum levels of TNF-${\alpha}$ in the malignant and tuberculous pleural effusions were similar (p>0.05). The cut off points for the pleural fluid TNF-${\alpha}$ level and TNF-${\alpha}$ ratio were found to be 136.4 pg/mL and 6.4, respectively. The sensitivity, specificity and area under the curve were 81%, 80% and 0.82 for the pleural fluid TNF-${\alpha}$ level (p<0.005) and 76%, 70% and 0.72 for the TNF-${\alpha}$ ratio (p<0.05). Conclusion : We conclude that pleural fluid TNF-${\alpha}$ level and TNF-${\alpha}$ ratio can distinguish a malignant pleural effusion from a tuberculous effusion, and can be additional markers in a differential diagnosis of tuberculous and malignant pleural effusion. The level of TNF-${\alpha}$ in the pleural fluid could be a more efficient marker than the TNF-${\alpha}$ ratio.

Inhibitory Effects of Myelophycus simplex Papenfuss Methanol Extract on Melanogenesis in B16F10 Melanoma Cells (바위수염 메탄올 추출물이 B16F10 흑색종 세포에서의 멜라닌합성에 미치는 영향)

  • Kim, Hyang Suk;Cheon, Ji Min;Kwon, Da Hye;Choi, Eun Ok;Kim, Min Ju;Choi, Yung Hyun;Kim, Byung Woo;Hwang, Hye Jin
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.46 no.1
    • /
    • pp.34-38
    • /
    • 2017
  • Myelophycus simplex Papenfuss, a type of brown algae, is known to be majorly distributed in along the southern coast of Korea and Japan. The purpose of this study was to investigate the effects of M. simplex Papenfuss methanol extract (MSPME) on melanogenesis in ${\alpha}$-melanocyte-stimulating hormone-stimulated B16F10 melanoma cells. Melanin contents of B16F10 melanoma cells were decreased by 27, 41, and 59% in a dose-dependent manner, upon MSPME treatment at 100, 300, and $500{\mu}g/mL$, respectively. Tyrosinase activities in B16F10 melanoma cells were decreased by 18, 49, and 61% in a dose-dependent manner, upon MSPME treatment at 100, 300, and $500{\mu}g/mL$, respectively. MSPME suppressed expression of tyrosinase, tyrosinase-related protein-1, tyrosinase-related protein-2, and melanocyte-inducing transcription factor in B16F10 melanoma cells. Concentration of $50{\mu}g/mL$ of MSPME especially induced greater decreases in tyrosinase activity, melanin contents, and melanogenic enzyme protein expressions. This results indicate that MSPME inhibits melanin synthesis and tyrosinase activity, and M. simplex Papenfuss extract may be an ideal candidate as a skin whitening agent.

THE EFFECTS OF TRANSFORMING GROWTH FACTOR-$\beta$ ON THE VIABILITY OF HUMAN PERIODONTAL LIGAMENT CELL AND ON THE EXPERIMENTAL TOOTH MOVEMENT IN RAT (Transforming growth factor-$\beta$가 인체 치주 인대세포 활성 및 백서의 실험적 치아 이동에 미치는 영향에 관한 연구)

  • Park, Yun-Kyung;Kim, Sang-Cheol
    • The korean journal of orthodontics
    • /
    • v.28 no.2 s.67
    • /
    • pp.311-327
    • /
    • 1998
  • The purpose of this study was to evaluate the effects of Transforming Growth Factor-${\beta}$ (TGF-${\beta}$) on the viability of human periodontal ligament cells, in-vitro and on the experimental tooth movement in rat, in-vivo. Human periodontal ligaments were cultured from the first premolar tooth extracted for the purpose of the orthodontic treatment. 0.1, 1, 5 and 10ng/m1 of TGF-${\beta}$ was given to the cultured wells, respectively and the viability was evaluated by MTT assay. Twenty Sprague-Dawley rats were divided into 5 experimental groups(4 rats in each) where 100g of force was applied from helical spring across the maxillary incisors. TGF-${\beta}$ was injected via Hamilton syringe into the periodontal ligament at the mesial and the distal surface of a maxillary incisor of 2 rats in each experimental group. Phosphate buffer saline(PBS) was injected in 2 other rats as controls. Experimental groups were sacrificed at 1, 3, 7, 14 and 28 days after force application, respectively. The obtained tissues were evaluated histologically. The obtained results were as follows: 1. The viability of periodontal ligament cells in 0.1ng/ml of TGF-${\beta}$ was not significantly different from that of control at 1-, 2- and 3-day of cultivation. 2. The viability of periodontal ligament cells was significantly increased at 3-day in 1ng/ml or 5ng/ml of TGF-${\beta}$, and at 2-,3-day in 10ng/ml of of TGF-${\beta}$. 3. The zone of hyalinization in periodontal ligament in pressure side was smaller in TGF-${\beta}$ injection group than that in control group at 3-day after the application of experimental force in rat. But no difference was seen after 7-day. 4. Osteoclastic activity and capillary prolieferation in pressure side were greater in TGF-${\beta}$ injection group than that in control group at 3-day to 7-day. 5. Osteoblastic activity and new bone fomation in tension side were greater in TGF-${\beta}$ injection group than that in control group at 3-day to 14-day.

  • PDF

Antioxidant Activity of Ethanol Extracts from Horseweed (Erigeron canadensis L.) with Pretreatment Conditions (전처리조건에 따른 망초(Erigeron canadensis L.) 에탄올 추출물의 항산화활성)

  • Woo, Koan-Sik;Song, Seuk-Bo;Oh, Byeong-Geun;Seo, Myung-Chul;Ko, Jee-Yeon;Lee, Jae-Saeng;Kang, Jong-Rae;Nam, Min-Hee;Jeong, Heon-Sang
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.38 no.9
    • /
    • pp.1279-1283
    • /
    • 2009
  • In order to investigate the potential characteristics of horseweed (Erigeron canadensis L.) recognized with weeds for the application to food industry, the antioxidative properties of horseweed were measured with total polyphenol, flavonoid, tannin, chlorophyll contests and antioxidant activities. Total polyphenol, flavonoid, tannin, and chlorophyll content were 63.32, 27.71, 161.19, and 428.85 mg/g in the extracts of fresh horseweed (FHE), respectively. The extracts of dry horseweed (DHE) on $40^{\circ}C$ for 48 hr were 89.25, 33.44, 210.44, and 229.29 mg/g, and the extracts of dry horseweed after blanching (BDHE) were 115.49, 45.51, 252.54, and 283.07 mg/g, respectively. $IC_{50}$ of EDA (electron donating ability, %) and AEAC (L-ascorbic acid equivalent antioxidant capacity) were 5.5527 mg/mL and 192.78 mg AA eq/g sample in the FHE, respectively. The DHE were 0.4710 mg/mL and 194.05 mg AA eq/g sample, and the BDHE were 0.4135 mg/mL and 242.40 mg AA eq/g sample, respectively. Horseweed, where the antioxidant activity is excellent, is thought to be potentially useful with foodstuffs.

The Role of Heme Oxygenase-1 in Lung Cancer Cells (폐암세포주에서 Heme Oxygenase-1의 역할)

  • Jung, Jong-Hoon;Kim, Hak-Ryul;Kim, Eun-Jung;Hwang, Ki-Eun;Kim, So-Young;Park, Jung-Hyun;Kim, Hwi-Jung;Yang, Sei-Hoon;Jeong, Eun-Taek
    • Tuberculosis and Respiratory Diseases
    • /
    • v.60 no.3
    • /
    • pp.304-313
    • /
    • 2006
  • Background : Heme oxygenase-1 (HO-1) is an inducible enzyme that catalyzes the oxidative degradation of heme to form biliverdin, carbon monoxide (CO), and free iron. The current evidence has indicated a critical role of HO-1 in cytoprotection and also in other, more diverse biological functions. It is known that the high expression of HO-1 occurs in various tumors, and that HO-1 has an important role in rapid tumor growth because of its antioxidative and antiapoptotic effects. Therefore, the role of HO-1 was analyzed in human lung cancer cell lines, and especially in the A549 cell line. Material and Methods : Human lung cancer cell lines, i.e., A549, NCI-H23, NCI-H157 and NCI-H460, were used for this study. The expression of HO-1 in the untreated state was defined by Western blotting. ZnPP, which is the specific HO inhibitor we used, and the viability of cells were tested for by conducting MTT assaysy. The HO enzymatic activity, as determined via the bilirubin level, was also indirectly measured. Moreover, the generation of intracellular hydrogen peroxide (H2O2) was monitored fluorimetrically with using a scopoletin-horse radish peroxidase (HRP) assay and 2',7'-dichlorofluorescein diacetate (DCFH-DA). We have also transfected small HO-1 interfering RNA (siRNA) into A549 cells, and the apoptotic effects were evaluated by flow cytometric analysis and Western blotting. Results : The A549 cells had a greater expression of HO-1 than the other cell lines, whereas ZnPP significantly decreased the viability of the A549 cells more than the viability of the other lung cancer cells in a dose-dependant fashion. Consistent with the viability, the HO enzymatic activity also was decreased. Moreover, intracellular H2O2 generation via ZnPP was induced in a dose-dependent manner. Apoptotic events were, then induced in the HO-1 siRNA transfected A549 cells. Conclusion : HO-1 provides new important insights into the possible molecular mechanism of the antitumor therapy in lung cancer.