• 제목/요약/키워드: Protective agents

검색결과 276건 처리시간 0.034초

Immunogenicity and Protective Efficacy of a Dual Subunit Vaccine Against Respiratory Syncytial Virus and Influenza Virus

  • Park, Min-Hee;Chang, Jun
    • IMMUNE NETWORK
    • /
    • 제12권6호
    • /
    • pp.261-268
    • /
    • 2012
  • Respiratory syncytial virus (RSV) and influenza virus are the most significant pathogens causing respiratory tract diseases. Composite vaccines are useful in reducing the number of vaccination and confer protection against multiple infectious agents. In this study, we generated fusion of RSV G protein core fragment (amino acid residues 131 to 230) and influenza HA1 globular head domain (amino acid residues 62 to 284) as a dual vaccine candidate. This fusion protein, Gcf-HA1, was bacterially expressed, purified by metal resin affinity chromatography, and refolded in PBS. BALB/c mice were intranasally immunized with Gcf-HA1 in combination with a mucosal adjuvant, cholera toxin (CT). Both serum IgG and mucosal IgA responses specific to Gcf and HA1 were significantly increased in Gcf-HA1/CT-vaccinated mice. To determine the protective efficacy of Gcf-HA1/CT vaccine, immunized mice were challenged with RSV (A2 strain) or influenza virus (A/PR/8/34). Neither detectable viral replication nor pathology was observed in the lungs of the immune mice. These results demonstrate that immunity induced by intranasal Gcf-HA1/CT immunization confers complete protection against both RSV and homologous influenza virus infection, suggesting our Gcf-HA1 vaccine candidate could be further developed as a dual subunit vaccine against RSV and influenza virus.

The Use of Chemical Additives to Protect SBS Rubbers Against Ozone Attack

  • Moakes, C.A.
    • Elastomers and Composites
    • /
    • 제34권2호
    • /
    • pp.177-182
    • /
    • 1999
  • SBS thermoplastic elastomers offer an inexpensive alternative to vulcanised rubbers for many undemanding applications. They are, however, particularly susceptible to attack from atmospheric ozone leading to cracking as soon as any strain is applied. In most rubber applications some strain is unavoidable. In this paper a compounding approach to protecting SBS thermoplastic rubbers against ozone is described. An explanation is offered for why a protective effect Is observed only when certain combinations of additive are used. SBS elastomers are the most affordable class of thermoplastic rubbers. To achieve finished products resistant to ozone and without compromising the light colours often demanded, recourse must be made to blending with other saturated elastomers or replacement by hydrogenated (SEBS) types. The latter is a significantly more expensive alternative. Under laboratory conditions where the rate of ozone attack is increased by several decades, unprotected SBS begins to crack within a few hours. Several different protective agents are examined here, the best of which, a cyclic enol ether, $Vulkazon^{(R)}$ AFD, can extend the resistance to any cracking to several weeks by the use of a few percent by weight of additive. The systems reported neither discolour the polymer nor stain other materials with which it may be in contact. Use of the protective systems described here could enable SBS elastomers to compete in many applications with the more expensive SEBS polymers.

  • PDF

산소중독에 대한 MALTOL의 보호효과에 관한 실험적 연구 (An Experimental Study on the Effect of Maltol against Oxygen Toxicity)

  • 황성주;조수헌;윤덕로
    • Journal of Preventive Medicine and Public Health
    • /
    • 제26권4호
    • /
    • pp.551-564
    • /
    • 1993
  • Since the widespread application of hyperbaric oxygenation in clinical medicine, the problems of oxygen toxicity have been attracting a deep interest from the researchers on hyperbaric medicine as a practical issue. Among extensive research trials, the study on the protective agents oxygen toxicity occupied one of the most challenging field. As the mechanisms of oxygen toxicity, the role of the oxygen free radicals produced by peroxidation process are strongly accepted by the leading researchers on oxygen toxicity, the probable protective effects of antioxidant against oxygen toxicity are sustaining a sufficient rational. Maltol ($2-methyl-3-hydroxy-{\gamma}-pyrone$) which is known to be a component of Korean red ginseng has been reporting to have an antioxidant action. But, further study is needed to provide definite evidence for this compound to be an antioxidant, since the action was based on the results which were obtained under in vitro experiment. In this study, the author attempted to evaluate the effect of maltol as protective agent against oxygen toxicity through the observation of death rate, convulsion rate, time to convulsion and microscopic pathological changes in some organs of experimental rats exposed to various conditions. The findings observed are as follows : 1) The death rate, convulsion rate, time to convulsion, lung/weight ratio and microscopic pathological finding of lung were identified as reliable objective and quantitative indices for oxygen toxicity. 2) Maltol showed excellent protective effect against pulmonary oxygen toxicity as an antioxidant.

  • PDF

Alginic acid-silica hydrogel coatings for the protection of ssmotic distillation membranes against wet-out by surface-active agents

  • Xu, J.B.;Spittler, D.A.;Bartley, J.P.;Johnson, R.A.
    • 한국고분자학회:학술대회논문집
    • /
    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
    • /
    • pp.354-354
    • /
    • 2006
  • Alginic acid-silica hydrogel films was prepared for testing as protective coating materials for PTFE OD membranes. Unprotected hydrophobic membranes are subject to wet-out when contacted by surface-active agents. Films were characterised using SEM, XRD, DSC, mechanical strength measurements, and water-swelling measurements. In OD trials using coated membranes, no wet-out occurred over the 15 h duration of three consecutive 5 h OD trials using orange oil-water mixtures. In the case of detergent solutions, the coating afforded protection to the membrane for 4-5 h. In a separate trial, no wet-out occurred when the coated side of the membrane was placed in contact with 1.2 wt % orange oil for 72 hours.

  • PDF

Differential Behaviour of Selenium Analogs against Anticancer Drug Induced Apoptosis of Lymphocytes in Human Peripheral Blood

  • Elango, Sonaa;Subbiah, Usha;Jain, Jeong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권5호
    • /
    • pp.2527-2533
    • /
    • 2016
  • Sensitising cancer cells and at the same time desensitizing normal cells is a double task in cancer management. Agents which can combat the debilitating side effects of cancer therapeutics and simultaneously synergize with anticancer agents in specifically targeting cancer cells are needed. Selenium, a proven anticarcinogen, gains due importance in terms of its efficacy to combat the side effects of cancer therapy. This study is a comparative analysis of the chemoprotective effects of selenium compounds, methyl selenol (generated from organic selenomethionine (5mmol/L ; METase 40U/L)) and sodium selenite (inorganic form)($30{\mu}M$) in peripheral blood human lymphocytes exposed to cisplatin and mitomycin. Biochemical alterations occurring in many cells during apoptosis include loss of plasma membrane phospholipid asymmetry, DNA fragmentation, and activation of caspase-3. The present study demonstrated that the selenium metabolite and selenite are efficient in protecting lymphocytes undergoing DNA damage and exerted their activity by reducing caspase 3 expression. Interestingly organic methylselenol (MeSe) was found to offer more protective effects compared to inorganic selenite (SeL), by reducing the induction of apoptosis by the cytotoxic agents. This suggests that MeSe and to a lesser extent selenite might have potential for assessment in clinical trials and could be considered as strong candidates in pharmacogenomics or in the nutriprotective arena.

평간개울지혈탕이 독성약물에 의한 간조직 손상에 미치는 영향 (Effect of Pyunggangaeuljihyul-tang (Pinggankaiyuzhixue-tang) on Toxic Agent Induced Liver Cell Damage)

  • 오세광;김원일;김우환
    • 대한한의학회지
    • /
    • 제24권3호
    • /
    • pp.96-107
    • /
    • 2003
  • Objective : This study was undertaken to determine if Pyunggangaeuljihyul-tang (Pinggankaiyuzhixue-tang, PG) has a protective effect against cell injury induced by various toxic agents in rabbit liver, Methods : Cell injury in vitro was estimated by measuring lactate dehydrogenase (LDH), and that in vivo was estimated by measuring alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity in serum. Lipid peroxidation was examined by measuring malondialdehyde, a product of lipid per oxidation. Results : PG prevented the LDH release by $CCl_4$, mercury, menadione, and tert-butyl hydroperoxide treatment in vitro in liver slices. The extent of protection by 2% PG was similar to that of $10{\mu\textrm{M}}$ N,N'-diphenyl-p-phenylenedianline, a potent antioxidant, in tert-butyl hydroperoxide-induced LDH release. PG also prevented lipid peroxidation and depletion of cellular ATP induced by Hg. Hg causes motphological changes including cell necrosis and its effect was significantly prevented by PG. When rats were treated intraperitoneatly with 0.5 ml/kg of $CCl_4$, serum alanine aminotransferase and aspartate aminotransferase activities were increased compared with the control, which was significantly inhibited by pretreatment of PG. PG also prevented reduction in GSH and lipid peroxidation induced by $CCl_4$ Conclusion : These results suggest that PG exerts aprotective effect against various toxic agents by its antioxidant action in liver tissues. Thus, PG may be used in prevention and treatment of drug-induced liver cell injury. However, the precise mechanisms of PG protection remain to be determined.

  • PDF

구아니딘화 폴리에틸렌이민이 처리된 폴리프로필렌 부직포의 군사용 화학 작용제 제독 특성 (Detoxification Properties of Guanidinylated Polyethyleneimine Treated Polypropylene Non-woven Fabric Against Chemical Warfare Agents)

  • 김지윤;권웅;김창규;정의경
    • 한국염색가공학회지
    • /
    • 제33권1호
    • /
    • pp.1-9
    • /
    • 2021
  • This study aims to prepare the fabric with detoxification properties against chemical warfare agent by the simple treatment. For this purpose, polypropylene non-woven fabric(PP) was treated with polyethyleneimine(PEI) and guanidinylated PEI and detoxification properties of the guanidinylated PEI treated PP were evaluated using diisopropylfluorophosphate(DFP), as a chemical warfare agent simulant, and compared with the untreated and PEI treated PP. The half-lives of DFP on guanidinylated PEI treated PP and untreated PP were 334 min and 714 min, respectively. The half-life of DFP with guanidinylated PEI treated PP was 53.22% shorter than with untreated PP. This result shows that guanidine group in guanidinylated PEI treated PP was acted as a base catalyst for hydrolysis of DFP and decreased half-life of DFP. Therefore, it is expected that guanidinylated PEI treatment can be an simple pathway to prepare the detoxification fabric material for protective clothing against chemical warfare agents.

삼백초(Saururus Chinensis (Lour.) Bail) 열추출물의 항암 및 세포독성 저해 효과 (Effect of Water Extract from Saururus Chinensis (Lour.) Bail Water Extracts on the Cancer Cells and Antioxidative Activity in Cytotoxicity)

  • 이인선
    • 한국식품저장유통학회지
    • /
    • 제8권2호
    • /
    • pp.213-216
    • /
    • 2001
  • Chemoprevetive effect of Saururus Chinensis (Lour.) Bail water extract on several tumor cells and Chinese hamster V79 cells were investigated. The water extracts of Saururus Chinensis (Lour.) Bail showed a higher cytotoxicity effect on the human histiocytic leukemia cells(U937) and protective effects against the cytotoxicity of H$_2$O$_2$. These results suggest that Saururus Chinensis (Lour.) Bail may useful as potential soures of chemopreventive and antioxidative agents.

  • PDF

Protective effect of Platycodon grandiflorum against t-butyl hydroperoxide-induced hepatic toxicity in rats

  • Lee, Kyung-Jin;Choi, Chul-Yung;Jeong, Hye-Gwang
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
    • /
    • pp.288.3-289
    • /
    • 2002
  • Increasing evidence regarding free radical generating agents and inflammatory processes suggests that accumulation of reactive oxygen species can cause hepatotoxicity. A short-chain analog of lipid hydroperoxide, t-butyl hydroperoxide (t-BHP), can be metabolized to free radical intermediates by cytochrome P-450 in hepatocytes. which in turn can initiate lipid peroxidation, affect cell integrity and result in cell injury. (omitted)

  • PDF

A Study on The Mechanism of Oxidative Stress, Screening of Protective Agents and Signal Transduction of Cell Differentiation in Cultured Osteoblast and Osteoclast Damaged by Reactive Oxygen Species

  • Park, Seung-Taeck;Han, Du-Suk
    • 한국독성학회:학술대회논문집
    • /
    • 한국독성학회 2003년도 춘계학술대회 논문집
    • /
    • pp.66-67
    • /
    • 2003
  • It is well known that osteoblasts and osteoc1asts playa key role in bone metabolism. They involve in osteoformation or bone destruction which are ragulated by various factors such as thyroid hormone, parathyroid hormone, estrogen, growth factor and cytokine. Recently, it is demonstrated that oxidative stress is one of pathological factors in bone metabolism, but it is left unknown about mechanism between oxidative stress and bone metabolism.(omitted)

  • PDF