• Title/Summary/Keyword: Protective agents

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Matrix metalloproteinase-13 downregulation and potential cartilage protective action of the Korean Red Ginseng preparation

  • Lee, Je Hyeong;Shehzad, Omer;Ko, Sung Kwon;Kim, Yeong Shik;Kim, Hyun Pyo
    • Journal of Ginseng Research
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    • v.39 no.1
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    • pp.54-60
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    • 2015
  • Background: The present study was designed to prepare and find the optimum active preparation or fraction from Korea Red Ginseng inhibiting matrix metalloproteinase-13 (MMP-13) expression, because MMP-13 is a pivotal enzyme to degrade the collagen matrix of the joint cartilage. Methods: From total red ginseng ethanol extract, n-BuOH fraction (total ginsenoside-enriched fraction), ginsenoside diol-type-enriched fraction (GDF), and ginsenoside triol-type-enriched fraction (GTF) were prepared, and ginsenoside diol type-/F4-enriched fraction (GDF/F4) was obtained from Panax ginseng leaf extract. Results: The n-BuOH fraction, GDF, and GDF/F4 clearly inhibited MMP-13 expression compared to interleukin-$1{\beta}$-treated SW1353 cells (human chondrosarcoma), whereas the total extract and ginsenoside diol-type-enriched fraction did not. In particular, GDF/F4, the most effective inhibitor, blocked the activation of p38 mitogen-activated protein kinase (p38 MAPK), c-Jun-activated protein kinase (JNK), and signal transducer and activator of transcription-1/2 (STAT-1/2) among the signal transcription pathways involved. Further, GDF/F4 also inhibited the glycosaminoglycan release from interleukin-$1{\alpha}$-treated rabbit cartilage culture (30.6% inhibition at $30{\mu}g/mL$). Conclusion: Some preparations from Korean Red Ginseng and ginseng leaves, particularly GDF/F4, may possess the protective activity against cartilage degradation in joint disorders, and may have potential as new therapeutic agents.

Preparation and application of silica-based coatings for corrosion protection of marine structures (해양구조물용 silica 기반 내해수성 코팅제의 제조 및 응용)

  • Lee, Byeong Woo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.31 no.3
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    • pp.137-142
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    • 2021
  • In this study, the development of the room temperature curable silica-based coating compositions for anticorrosive and antifouling performance in marine environments was carried out. The marine (plant) structures with many exposed parts are operated in harsh marine environments such as strong ultraviolet rays, extreme temperature differences and salt water corrosion. Organic paints that are easily degraded under these environments and easily eroded by physical stimuli such as waves can not play a role properly. Dense ceramic coatings on marine structures provide careful protections even in saltwater environments due to their high hardness and rust resistance. Therefore, in the case of ceramic coatings, their use and application range in marine structures can be greatly improved due to their functional advantages. In the present study, silica-based coating compositions based on colloidal silica with silane coupling agents, curing salts, and ceramic fillers were developed, and their applications as protective coatings for corrosion protection and fouling prevention in seawater were also studied.

Protective Measures From Solar Ultraviolet Radiation for Beach Lifeguards in Tuscany (Italy): Shade and Clothing Strategies

  • Daniele Grifoni;Giulio Betti;Andrea Bogi;Lucia Bramanti;Alessandra Chiarugi;Bernardo Gozzini;Marco Morabito;Francesco Picciolo;Francesco Sabatini;Lucia Miligi
    • Safety and Health at Work
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    • v.13 no.4
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    • pp.421-428
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    • 2022
  • Background: The exposure to solar ultraviolet radiation is a significant risk factor generally underestimated by outdoor workers and employers. Several studies have pointed out that occupational solar exposure increased eye and skin diseases with a considerable impact on the lives and productivity of affected workers. The main purpose of this study was to evaluate the effectiveness against ultraviolet radiation of some measures recently undertaken for the protection of lifeguards in a coastal area of Tuscany. Methods: Different shading structures (gazebos and beach umbrella) were tested during a sunny summer's day on a sandy beach by means of two radiometers; the UV protection offered by some T-shirts used by lifeguards was also tested in the laboratory with a spectrophotometer. Results: The analysed shading structures strongly reduced the ultraviolet radiation by up to 90%, however a not always negligible diffuse radiation is also present in the shade, requiring further protective measures (T-shirt, sunglasses, sunscreen, etc.); the tested T-shirts showed a very good-excellent protection according to the Australian/New Zealand standard. Conclusion: Results obtained in this study suggest how the adoption and dissemination of good practices, including those tested, could be particularly effective as a primary prevention for lifeguards who are subjected to very high levels of radiation for long periods.

Signal Transduction Events Elicited by Natural Products: Role of MAPK and Caspase Pathways in Homeostatic Response and Induction of Apoptosis

  • Kong, Ah-Ng Tony;Yu, Rong;Chen, Chi;Mandlekar, Sandhya;Primiano, Thomas
    • Archives of Pharmacal Research
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    • v.23 no.1
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    • pp.1-16
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    • 2000
  • Many natural products elicit diverse pharmacological effects. Using two classes of potential chemopreventive compounds, the phenolic compounds and the isothiocyanates, we review the potential utility of two signaling events, the mitogen-activated protein kinases (MAPKs) and the ICE/Ced-3 proteases (caspases) stimulated by these agents in mammalian cell lines. Studies with phenolic antioxidants (BHA, tBHQ), and natural products (flavonoids; EGCG, ECG, and isothiocyanates; PEITC, sulforaphane), provided important insights into the signaling pathways induced by these compounds. At low concentrations, these chemicals may activate the MAPK (ERK2, JNK1, p38) leading to gene expression of survival genes (c-Fos, c-Jun) and defensive genes (Phase II detoxifying enzymes; GST, QR) resulting in survival and protective mechanisms (homeostasis response). Increasing the concentrations of these compounds will additionally activate the caspase pathway, leading to apoptosis (potential cytotoxicity). Further increment to suprapharmacological concentrations will lead to nonspecific necrotic cell death. The wider and narrow concentration ranges between the activation of MAPK/gene induction and caspases/cell death exhibited by phenolic compounds and isothiocyanates, respectively, in mammalian cells, may reflect their respective therapeutic windows in vivo. Consequently, the studies of signaling pathways elicited by natural products will advance our understanding of their efficacy and safety, of which many man become important therapeuitc drugs of the future.

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A Descriptive Study of Occupational Health Services in Self-employed Enterprises (Nanoscale Enterprises), Shiraz, Iran

  • Jahangiri, Mehdi;Rostamabadi, Akbar;Yekzamani, Parvaneh;Abadi, Bahare Mahmood;Behbood, Fariborz;Ahmadi, Seyyedeh Fatemeh;Momeni, Zahra
    • Safety and Health at Work
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    • v.7 no.4
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    • pp.317-321
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    • 2016
  • Background: This study was conducted with aim of providing an overview of the current status of occupational health services and identifying the most common harmful agents at workplaces of Iranian self-employed enterprises (Nano-Scale Enterprises). Methods: A cross-sectional study was performed among a random sample including 1,758 employees engaging in self-employed enterprises with 5 and less employees. Results: Coverage of occupational health surveillance was very poor, annual health examinations were been conducted only for 64 (3.64%) of males and 31 (1.76%) of females, and occupational health trainings were not included of the services at all. Personal Protective Equipment were available in 462 (26.3%) of the enterprises. only in 0.4% of the enterprises working processes were been equipped by a local exhaust ventilation system. Difficult postures were the most common (81.5%) adverse working conditions. Conclusion: This study revealed a poor level of the implementation of occupational health services in Iranian self-employed enterprises. Based on the findings, providing basic training on the occupational health, more enforcing in conduction of health examinations and providing PPE, and taking appropriate strategies aimed at eliminating or minimizing work environment harmful agents are the major factor that should be considered to improve the level of occupational health services among the studied enterprises.

Effects of Natural Products on the Induction of NAD(P)H: Quinone Reductase in Hepa 1c1c7 Cells for the Development of Cancer Chemopreventive Agents

  • Kim, Young-Mi;Chang, Il-Moo;Mar, Woong-Chon
    • Natural Product Sciences
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    • v.3 no.2
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    • pp.81-88
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    • 1997
  • NAD(P)H:quinone reductase (QR) is one of the protective phase II enzymes against toxicity that accomplishes the capacity of detoxification by modulating the effects of mutagens and carcinogens. The detoxification mechanism is that quinone reductase promotes the 2-electron reduction of quinones to hydroquinones which are less reactive. This study is to search new inducers of quinone reductase from natural products, which can be used as cancer chemopreventive agents. Plant extracts were evaluated by using quinone reductase generating system With Hepa 1c1c7 murine hepatoma cell lines for enzyme inducing properties and crystal violet staining method for the measurement of cytotoxicity provoked. We have tested approximately 106 kinds of natural products after partition into n-hexane, ethyl acetate and aqueous layers from 100% methanol extracts of natural products. The ethyl acetate fractions of Vitex rotundifolia $(fruits,\;2FC:\;12.7\;{\mu}g/ml)$, Cnidium officinale $(aerial\;parts,\;2FC:\;10.5\;{\mu}g/ml)$, Chrysanthemum sinese $(flowers,\;2FC:\;17.4{\mu}g/ml)$ and the hexane fractions of Angelica gigas $(roots,\;2FC:\;13.2\;{\mu}g/ml)$, Smilax china $(roots,\;2FC:\;l1.9\;{\mu}g/ml)$, Sophora flavescens $(roots,\;2FC:\;16.3\;{\mu}g/ml)$ revealed the significant induction of quinone reductase in a murine hepatic Hepa 1c1c7 cell culture system.

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방사선(放射線) 조사후(照射後)의 N:GP(S) mouse 비장세포(脾臟細胞) 증식(增殖)에 미치는 보중익기탕(補中益氣湯)과 사육탕(四六湯)의 효과

  • Lee, Neung-Gi;Choe, Seung-Hun
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.2 no.1
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    • pp.91-100
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    • 1996
  • Radiotherapy is an irreplaceable method of cancer treatment but, it has various side effects, especially damage to the hemopoietic system. A lot of radioprotectors have been found but they also have toxic effects. Many kinds of crude drugs(Oriental Chinese medicine)with low toxicity have been reported to promote the recovery from radiation damage. Recently, the trial to combine radiotherapy with herbal treatment of cancer patients shows a desirable result, an enhancement in recovery of the blood system.. This study was performed to determine whether prescriptions to support the healthy energy and strengthen the body resistence, Buzhongyiqi-tang and Siliu-tang, promote the recovery of splenocytes of N:GP(s) mice from radiation damage. We investigated the proliferative effect of Buzhongyiqi-tang, Siliu-tang and EIB(ethanol insoluble fraction of Buzhongyiqi-tang) on N:GP(S)mice splenocytes before or after ${\gamma}$-irradiation. We also investigated the morphology of splenocytes cultured with these herbs. Buzhongyiqi-tang and Siliu-tang promoted the proliferation of splenocytes in a concentration of 0.1 mg/ml compared with normal control(p<0.001). After 1-5Gy of ${\gamma}$-irradiation they also showed the effect of recovery of hemopoietic cells, especially in Buzhongyiqi-tang(4Gy:p<0.005; 5Gy:p<0.05). In addition, EIB(ethanol insoluble fraction of Buzhongyiqi-tang) showed the highest proliferative effect of all agents suggesting that more effective fractions could be found from crude herbs or prescriptions. These results suggest that it is possible to make use of Buzhongyiqi-tang, Siliu-tang or EIB as radio-protective agents.

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Inactivation of the Wall-Associated De-N-acetylase (PgdA) of Listeria monocytogenes Results in Greater Susceptibility of the Cells to Induced Autolysis

  • Popowska, Magdalena;Kusio, Monika;Szymanska, Paulina;Markiewicz, Zdzislaw
    • Journal of Microbiology and Biotechnology
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    • v.19 no.9
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    • pp.932-945
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    • 2009
  • Several species of Gram-positive bacteria have cell wall peptidoglycan (syn. murein) in which not all of the sugar moieties are N-acetylated. This has recently been shown to be a secondary effect, caused by the action of a peptidoglycan N-acetylglucosamine deacetylase. We have found that the opportunistic pathogen Listeria monocytogenes is unusual in having three enzymes with such activity, two of which remain in the cytoplasm. Here, we examine the enzyme (PgdA) that crosses the cytoplasmic membrane and is localized in the cell wall. We purified a hexa-His-tagged form of PgdA to study its activity and constructed a mutant devoid of functional Lmo0415 (PgdA) protein. L. monocytogenes PgdA protein exhibited peptidoglycan N-acetylglucosamine deacetylase activity with natural substrates (peptidoglycan) from both L. monocytogenes and Escherichia coli as well as the peptidoglycan sugar chain component N-acetylglucosamine, but not with N-acetylmuramic acid. As was reported recently [6], inactivation of the structural gene was not lethal for L. monocytogenes nor did it affect growth rate or morphology of the cells. However, the pgdA mutant was more prone to autolysis induced by such agents as Triton X-100 and EDTA, and is more susceptible to the cationic antimicrobial peptides (CAMP) lysozyme and mutanolysin, using either peptidoglycan muramidases or autolysis-inducing agents. The pgdA mutant was also slightly more susceptible than the wild-type strain to the action of certain beta-lactam antibiotics. Our results indicate that protein PgdA plays a protective physiological role for listerial cells.

Isolation and Genetic Mapping of Paraquat Resistant Sporulating Mutants of Streptomyces Coelicolor

  • Chung, Hye-Jung;Kim, Eun-Ja;Park, Uhn-Mee;Roe, Jung-Hye
    • Journal of Microbiology
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    • v.33 no.3
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    • pp.215-221
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    • 1995
  • S. coelicolor A3(2) cells were treated with various redox-cycling agents on nutrient agar plates and examined for their effect on the growth and differentiation. When treated with plumbagin, severe effect on cell viability was observed at concentrations above 250 $\mu$M. However, the surviving colonies differentiated normally. When treated with 100 $\mu$M paraquat, growth rate was decreased and morphological differentiation was inhibited, while the survival rate was maintained at about 100% even at 5 mM paraquat. Menadione or lawsone did not cause any visible changes at concentrations up to 1 mM. The effect of paraquat was also observed when it was added to nutrient agar plate before spore inoculation. Paraquat had also observed when it was added to nutrient agar plate before spore inoculation. Paraquat had no effect on colonies growing on R2YE agar plates. Among the components of R2YE medium selectively added to nutrient agar medium, CaCl$_2$ was found to have some protective function from the inhibitory effect of paraquat. As a first step to study the mechanism of the inhibitory effect of paraquat on differentiation, resistant mutants which sporulate well in the presence of paraquat were screened following UV mutagenesis. Three paraquat-resistant mutants were isolated with a frequency of 3 $\times$10${-5}$. Their mutation sites were determined by genetic crossings. All three mutations were mapped to a single locus near arg4 at about 1 o'clock on the genetic map of S. coelicolor A3(2).

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Engineered Recombinant PON1-OPH Fusion Hybrids: Potentially Effective Catalytic Bioscavengers against Organophosphorus Nerve Agent Analogs

  • Lee, Nari;Yun, Hyeongseok;Lee, Chan;Lee, Yikjae;Kim, Euna;Kim, Sumi;Jeon, Hyoeun;Yu, Chiho;Rho, Jaerang
    • Journal of Microbiology and Biotechnology
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    • v.31 no.1
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    • pp.144-153
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    • 2021
  • Organophosphorus nerve agents (OPNAs), including both G- and V-type nerve agents such as sarin, soman, tabun and VX, are extremely neurotoxic organophosphorus compounds. Catalytic bioscavengers capable of hydrolyzing OPNAs are under development because of the low protective effects and adverse side effects of chemical antidotes to OPNA poisoning. However, these bioscavengers have certain limitations for practical application, including low catalytic activity and narrow specificity. In this study, we generated a fusion-hybrid form of engineered recombinant human paraoxonase 1 (rePON1) and bacterial organophosphorus hydrolase (OPH), referred to as GV-hybrids, using a flexible linker to develop more promising catalytic bioscavengers against a broad range of OPNAs. These GV-hybrids were able to synergistically hydrolyze both G-type OPNA analogs (paraoxon: 1.7 ~ 193.7-fold, p-nitrophenyl diphenyl phosphate (PNPDPP): 2.3 ~ 33.0-fold and diisopropyl fluorophosphates (DFP): 1.4 ~ 22.8-fold) and V-type OPNA analogs (demeton-S-methyl (DSM): 1.9 ~ 34.6-fold and malathion: 1.1 ~ 4.2-fold above) better than their individual enzyme forms. Among the GV-hybrid clones, the GV7 clone showed remarkable improvements in the catalytic activity toward both G-type OPNA analogs (kcat/Km (106 M-1 min-1): 59.8 ± 0.06 (paraoxon), 5.2 ± 0.02 (PNPDPP) and 47.0 ± 6.0 (DFP)) and V-type OPNA analogs (kcat/Km (M-1 min-1): 504.3 ± 48.5 (DSM) and 1324.0 ± 47.5 (malathion)). In conclusion, we developed GV-hybrid forms of rePON1 and bacterial OPH mutants as effective and suitable catalytic bioscavengers to hydrolyze a broad range of OPNA analogs.