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Efficiency and Midgut Histopathological Effect of the Newly Isolated Bacillus thuringiensis KS ${\delta}$-Endotoxins on the Emergent Pest Tuta absoluta

  • Jamoussi, Kais;Sellami, Sameh;Nasfi, Zina;Krichen-Makni, Saloua;Tounsi, Slim
    • Journal of Microbiology and Biotechnology
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    • v.23 no.8
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    • pp.1099-1106
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    • 2013
  • Tuta absoluta (Povolny, 1994) is a devastating moth to the Solanaceae plants. It is a challenging pest to control, especially on tomatoes. In this work, we studied the entomopathogenic activity of the Cry-forming ${\delta}$-endotoxins produced by Bacillus thuringiensis strain KS and B. thuringiensis kurstaki reference strain HD1 against T. absoluta. These strains carried the cry2, cry1Ab, cry1Aa/cry1Ac, and cry1I genes, and KS also carried a cry1C gene. The ${\delta}$-endotoxins of KS were approximately twofold more toxic against the third instar larvae than those of HD1, as they showed lower 50% and 90% lethal concentrations (0.80 and 2.70 ${\mu}g/cm^2$ (${\delta}$-endotoxins/tomato leaf)) compared with those of HD1 (1.70 and 4.50 ${\mu}g/cm^2$) (p < 0.05). Additionally, the larvae protease extract showed at least six caseinolytic activities, which activated the KS and HD1 ${\delta}$-endotoxins, yielding the active toxins of about 65 kDa and the protease-resistant core of about 58 kDa. Moreover, the histopathological effects of KS and HD1 ${\delta}$-endotoxins on the larvae midgut consisted of an apical columnar cell vacuolization, microvillus damage, and epithelial cell disruption. These results showed that the KS strain could be a candidate for T. absoluta control.

Cordyceps militaris alleviates non-alcoholic fatty liver disease in ob/ob mice

  • Choi, Ha-Neul;Jang, Yang-Hee;Kim, Min-Joo;Seo, Min Jeong;Kang, Byoung Won;Jeong, Yong Kee;Kim, Jung-In
    • Nutrition Research and Practice
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    • v.8 no.2
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    • pp.172-176
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    • 2014
  • BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is becoming an important public health problem as metabolic syndrome and type 2 diabetes have become epidemic. In this study we investigated the protective effect of Cordyceps militaris (C. militaris) against NAFLD in an obese mouse model. MATERIALS/METHODS: Four-week-old male ob/ob mice were fed an AIN-93G diet or a diet containing 1% C. militaris water extract for 10 weeks after 1 week of adaptation. Serum glucose, insulin, free fatty acid (FFA), alanine transaminase (ALT), and proinflammatory cytokines were measured. Hepatic levels of lipids, glutathione (GSH), and lipid peroxide were determined. RESULTS: Consumption of C. militaris significantly decreased serum glucose, as well as homeostasis model assessment for insulin resistance (HOMA-IR), in ob/ob mice. In addition to lowering serum FFA levels, C. militaris also significantly decreased hepatic total lipids and triglyceride contents. Serum ALT activities and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin-6 (IL-6) levels were reduced by C. militaris. Consumption of C. militaris increased hepatic GSH and reduced lipid peroxide levels. CONCLUSIONS: These results indicate that C. militaris can exert protective effects against development of NAFLD, partly by reducing inflammatory cytokines and improving hepatic antioxidant status in ob/ob mice.

Stigmalactam from Orophea Enterocarpa Induces Human Cancer Cell Apoptosis Via a Mitochondrial Pathway

  • Banjerdpongchai, Ratana;Wudtiwai, Benjawan;Pompimon, Wilart
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.23
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    • pp.10397-10400
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    • 2015
  • Stigmalactam, an aristolactam-type alkaloid extracted from Orophea enterocarpa, exerts cytotoxicity against several human and murine cancer cell lines, but the molecular mechanisms remain elusive. The aims of this study were to identify the mode and mechanisms of human cancer cell death induced by stigmalactam employing human hepatocellular carcinoma HepG2 and human invasive breast cancer MDA-MB-231 cells as models, compared to normal murine fibroblasts. It was found that stigmalactam was toxic to HepG2 and MDA-MB-231 cells with $IC_{50}$ levels of $23.0{\pm}2.67{\mu}M$ and $33.2{\pm}4.54{\mu}M$, respectively, using MTT assays. At the same time the $IC_{50}$ level towards murine normal fibroblast NIH3T3 cells was $24.4{\pm}6.75{\mu}M$. Reactive oxygen species (ROS) production was reduced in stigmalactam-treated cells dose dependently after 4 h of incubation, indicating antioxidant activity, measured by using 2',7',-dichlorohydrofluorescein diacetate and flow cytometry. Caspase-3 and caspase-9 activities were increased in a dose response manner, while stigmalactam decreased the mitochondrial transmembrane potential dose-dependently in HepG2 cells, using 3,3'-dihexyloxacarbocyanine iodide and flow cytometry, indicating mitochondrial pathway-mediated apoptosis. In conclusion, stigmalactam from O. enterocarpa was toxic to both HepG2 and MDA-MB-231 cells and induced human cancer HepG2 cells to undergo apoptosis via the intrinsic (mitochondrial) pathway.

3,4,5-Trihydroxycinnamic Acid Inhibits LPS-Induced iNOS Expression by Suppressing NF-${\kappa}B$ Activation in BV2 Microglial Cells

  • Lee, Jae-Won;Bae, Chang-Jun;Choi, Yong-Jun;Kim, Song-In;Kim, Nam-Ho;Lee, Hee-Jae;Kim, Sung-Soo;Kwon, Yong-Soo;Chun, Wan-Joo
    • The Korean Journal of Physiology and Pharmacology
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    • v.16 no.2
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    • pp.107-112
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    • 2012
  • Although various derivatives of caffeic acid have been reported to possess a wide variety of biological activities such as neuronal protection against excitotoxicity and anti-inflammatory property, the biological activity of 3,4,5-trihydroxycinnamic acid (THC), a derivative of hydroxycinnamic acids, has not been clearly examined. The objective of the present study is to evaluate the anti-inflammatory effects of THC on lipopolysaccharide (LPS)-stimulated BV2 microglial cells. THC significantly suppressed LPS-induced excessive production of nitric oxide (NO) and expression of iNOS, which is responsible for the production of iNOS. THC also suppressed LPS-induced overproduction of pro-inflammatory cytokines such as IL-$1{\beta}$and TNF-${\alpha}$ in BV2 microgilal cells. Furthermore, THC significantly suppressed LPS-induced degradation of $I{\kappa}B$, which retains NF-${\kappa}B$ in the cytoplasm. Therefore, THC attenuated nuclear translocation of NF-${\kappa}B$, a major pro-inflammatory transcription factor. Taken together, the present study for the first time demonstrates that THC exhibits antiinflammatory activity through the suppression of NF-${\kappa}B$ transcriptional activation in LPS-stimulated BV2 microglial cells.

Anti-inflammation effect of Exercise and Korean red ginseng in aging model rats with diet-induced atherosclerosis

  • Lee, Jin;Cho, Joon-Yong;Kim, Won-Kyu
    • Nutrition Research and Practice
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    • v.8 no.3
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    • pp.284-291
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    • 2014
  • BACKGROUND/OBJECTIVES: The aim of this study was to investigate the effects of exercise (EX) and Korean red ginseng (KRG) on inflammation mechanism in aging model rats with diet-induced atherosclerosis. MATERIALS/METHODS: Forty-eight male Sprague-Dawley rats were divided into 6 groups: Young control (Y-C), Aging control (A-C), A-C with HFD (AHF), AHF with EX (AHF-EX), AHF-EX with KRG (AHF-EX+RG), and AHF with KRG (AHF-RG). Aging was induced by D-gal (100mg/kg) and atherosclerosis was induced by HFD (60% fat) for 9 weeks. The experimental rats were performed swimming (60 min/day, 5 days/week) and supplied KRG orally (dose of 200 mg/kg) for 8 weeks. All rat aorta samples were harvested for biochemical and immunohistochemical analyses. REULTS: The EX and KRG supplementation significantly inhibited body weight and levels of TC, TG, LDL-C, and enhance of HDL-C compared with untreated AHF groups. AHF-EX, AHF-EX+RG, and AHF-RG group showed a decreased plasma CRP and increase plasma NO activities compared to AHF group. In addition, these groups revealed reduced 4-HNE, NF-kB, TNF-, ${\alpha}$, IL-6, COX-2, ICAM-1, VCAM-1 and enhanced eNOS expression in the aorta. CONCLUSION: These results suggest that EX alone, KRG alone, and combined treatment of EX and KRG may be an effective anti-inflammatory therapeutic for the atherosclerosis, possibly acting via the decreased of CRP and pro-inflammation proteins and the increased NO and eNOS.

Orostachys japonicus Hexane Fraction Attenuates Pro-inflammatory Cytokines in LPS-activated Macrophage Cells by Suppression of AP-1 and IRF3 Transcription Factors (LPS로 유도된 대식세포에 대한 와송 핵산추출물의 AP-1과 IRF3 전사인자의 억제에 의한 전염증성 사이토카인의 감소 효과)

  • Lee, Hyeong-Seon
    • Microbiology and Biotechnology Letters
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    • v.48 no.3
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    • pp.310-315
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    • 2020
  • Orostachys japonicus (O. japonicus) is known as a medicinal plant for the treatment of various symptoms. This study investigated the anti-inflammatory effect of the hexane fraction from O. japonicus (OJH) on the LPS-stimulated response in RAW 264.7 macrophage cells. This study was conducted to confirm the effect of cell cytotoxicity and production of reactive oxygen species (ROS) in OJH-treated macrophage cells. Additionally, pro-inflammatory cytokines and transcription factors were determined using RT-PCR and western blotting assay. OJH showed no change in lactate dehydrogenase (LDH) levels and exhibited reduced ROS levels in LPS-induced inflammatory cells. Moreover, OJH significantly suppressed the mRNA levels of proinflammatory cytokines, including IL-1β, IL-2, IL-6, TNF-α, and IP-10. Furthermore, OJH effectively inhibited the protein levels of AP-1 (p-c-Jun and p-c-Fos) and p-IRF3 in a dose-dependent manner. In conclusion, our results demonstrate that OJH exhibits strong anti-inflammatory activities via regulation of inflammatory factors.

Preventive Effects of Chitosan on the Disorders of Hepatic Functions and Lipid Metabolism in Rats Treated with 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) (다이옥신계 TCDD (2, 3, 7, 8-tetrachlorodibenzo-p-dioxin)에 노출된 흰쥐의 지질대사 및 간 독성물질대사에 관한 키토산의 예방효과)

  • Lee Joon-Ho;Hwang Seok-Youn;Lee Yeon-Sook
    • Journal of Nutrition and Health
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    • v.38 no.9
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    • pp.689-697
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    • 2005
  • This study was conducted to fine out the preventive effects of chitosan and chitosan oligomer on the disorders of hepatic functions and lipid metabolism induced by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) using adult male rats (SD) for four weeks. Rats were fed chitosan ($4\%$) or chitosan oligomer ($4\%$) diets respectively before 3weeks of TCDD treatment (50 ug/kg BW) by intraperitoneal injection and then continually supplied these diets for one week until being sacrificed. The elevation of serum total and LDL cholesterol levels induced by TCDD treatment was significantly reduced in the rats fed chitosan diets. The increment of liver triglyceride levels caused by TCDD treatment was tended to suppress in all rats fed chitosan and chitosan oligomer diets. Fecal total lipid and cholesterol excretion were high levels in the rats fed chitosan diets. The hepatic cytosolic catalase activities significantly decreased by TCDD treatment appeared recovering trend by chitosan diets. In hepatic microsomal cytochrome p-450, NADPH cytochrome p-450 reductase, ethoxycoumarin-o-deethylase (ECOD) and benzphetamin N-demethylase (BPND) chitosan than chitosan oligomer diets apparently decreased the increasing levels by TCDD treatment. In histochemical observation the fat droplets and apoptosis of hepatocytes by TCDD treatment were markedly alleviated by chitosan and chitosan oligomer diets. These results indicate that chitosan, more than chitosan oligomer can exert preventive effects on some disorders of hepatic functions and lipids accumulation by TCDD.

Epigallocatechin-3-Gallate (EGCG) Attenuates Traumatic Brain Injury by Inhibition of Edema Formation and Oxidative Stress

  • Zhang, Bo;Wang, Bing;Cao, Shuhua;Wang, Yongqiang
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.6
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    • pp.491-497
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    • 2015
  • Traumatic brain injury (TBI) is a major cause of mortality and long-term disability, which can decrease quality of life. In spite of numerous studies suggesting that Epigallocatechin-3- gallate (EGCG) has been used as a therapeutic agent for a broad range of disorders, the effect of EGCG on TBI remains unknown. In this study, a weight drop model was established to evaluate the therapeutic potential of EGCG on TBI. Rats were administered with 100 mg/kg EGCG or PBS intraperitoneally. At different times following trauma, rats were sacrificed for analysis. It was found that EGCG (100 mg/kg, i.p.) treatment significantly reduced brain water content and vascular permeability at 12, 24, 48, 72 hour after TBI. Real-time PCR results revealed that EGCG inhibited TBI-induced IL-$1{\beta}$ and TNF-${\alpha}$ mRNA expression. Importantly, CD68 mRNA expression decreasing in the brain suggested that EGCG inhibited microglia activation. Western blotting and immunohistochemistry results showed that administering of EGCG significantly inhibited the levels of aquaporin-4 (AQP4) and glial fibrillary acidic protein (GFAP) expression. TBI-induced oxidative stress was remarkably impaired by EGCG treatment, which elevated the activities of SOD and GSH-PX. Conversely, EGCG significantly reduced the contents of MDA after TBI. In addition, EGCG decreased TBI-induced NADPH oxidase activation through inhibition of $p47^{phox}$ translocation from cytoplasm to plasma membrane. These data demonstrate that EGCG treatment may be an effective therapeutic strategy for TBI and the underlying mechanism involves inhibition of oxidative stress.

Addressing Mobile Agent Security through Agent Collaboration

  • Jean, Evens;Jiao, Yu;Hurson, Ali-R.
    • Journal of Information Processing Systems
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    • v.3 no.2
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    • pp.43-53
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    • 2007
  • The use of agent paradigm in today's applications is hampered by the security concerns of agents and hosts alike. The agents require the presence of a secure and trusted execution environment; while hosts aim at preventing the execution of potentially malicious code. In general, hosts support the migration of agents through the provision of an agent server and managing the activities of arriving agents on the host. Numerous studies have been conducted to address the security concerns present in the mobile agent paradigm with a strong focus on the theoretical aspect of the problem. Various proposals in Intrusion Detection Systems aim at securing hosts in traditional client-server execution environments. The use of such proposals to address the security of agent hosts is not desirable since migrating agents typically execute on hosts as a separate thread of the agent server process. Agent servers are open to the execution of virtually any migrating agent; thus the intent or tasks of such agents cannot be known a priori. It is also conceivable that migrating agents may wish to hide their intentions from agent servers. In light of these observations, this work attempts to bridge the gap from theory to practice by analyzing the security mechanisms available in Aglet. We lay the foundation for implementation of application specific protocols dotted with access control, secured communication and ability to detect tampering of agent data. As agents exists in a distributed environment, our proposal also introduces a novel security framework to address the security concerns of hosts through collaboration and pattern matching even in the presence of differing views of the system. The introduced framework has been implemented on the Aglet platform and evaluated in terms of accuracy, false positive, and false negative rates along with its performance strain on the system.

Cellular Biomarker of Membrane Stability and Hydrolytic Enzyme Activity in the Hemocytes of Benzo(a)pyrene-exposed Pacific oyster, Crassostrea gigas

  • Jo Qtae;Choy Eun-Jung;Park Doo Won;Jee Young-Ju;Kim Sung Yeon;Kim Yoon
    • Fisheries and Aquatic Sciences
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    • v.5 no.4
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    • pp.263-270
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    • 2002
  • The Pacific oysters, Crassostrea gigas, were stressed with different concentrations of benzo(a) pyrene and depurated to determine the hemocyte lysosomal membrane stability and hydrolytic enzymatic activity as a biomarker candidate to the chemical, using NRR (neutral red retention) and API ZYM System, respectively. The membrane damage measured as NRR decrease was significant with the increase of chemical concentration and exposure time (P<0.05), providing a possible tool for biomarker. Interestingly, the control showed intrinsic stress probably due to captive life in the laboratory, and a recovering trend was also found during the depuration. The benzo(a)pyrene-exposed oysters showed increased enzyme activities in alkaline phosphatase, esterase (C4), acid phosphatase, naphthol-AS-BI-phospho­hydrolase, $\beta$-galactosidase, $\beta$-glucuronidase, and N-acetyl- $\beta$-glucosaminidase. Of them, only two enzymes, acid phosphatase and alkaline phosphatase, showed some potential available for the generation of enzymatic biomarker in the oyster. The results are suggestive of the potential availability of the cellular and enzymatic properties as a biomarker. However, considering that a robust biomarker should be insensitive to natural stress coming from normal physiological variation, but sensitive to pollutants, a concept of intrinsic stress the animal possesses should be taken into consideration. This reflects the necessity of further research on the intrinsic stress affecting the cellular and enzymatic properties of the chemical­stressed oysters prior to using the data as a biomarker.