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Sample records for natural agent deguelin

  1. Deguelin inhibits proliferation and migration of human pancreatic cancer cells in vitro targeting hedgehog pathway

    PubMed Central

    Zheng, Wen; Lu, Shiliu; Cai, Haolei; Kang, Muxing; Qin, Wenjie; Li, Chao; Wu, Yulian

    2016-01-01

    Pancreatic cancer (PC) is a highly lethal malignancy with few effective therapies. Deguelin, a natural compound of the flavonoid family of products, has been reported to have an inhibitory effect on various cancers. In the present study, we investigated whether deguelin had antitumor efficacy in PC. Deguelin treatment was observed to inhibit growth and induce apoptosis in two PC cell lines (Bxpc-3 and Panc-1). In addition, it inhibited migration and invasion in these two cell lines. The activation of the hedgehog (Hh) signaling pathway, as well as matrix metalloproteinases (MMP)-2 and MMP-9, was suppressed by deguelin. These results suggest that deguelin may be a potential chemotherapeutic agent for PC, possibly through the suppression of the Hh signaling pathway. PMID:27698853

  2. Deguelin inhibits proliferation and migration of human pancreatic cancer cells in vitro targeting hedgehog pathway

    PubMed Central

    Zheng, Wen; Lu, Shiliu; Cai, Haolei; Kang, Muxing; Qin, Wenjie; Li, Chao; Wu, Yulian

    2016-01-01

    Pancreatic cancer (PC) is a highly lethal malignancy with few effective therapies. Deguelin, a natural compound of the flavonoid family of products, has been reported to have an inhibitory effect on various cancers. In the present study, we investigated whether deguelin had antitumor efficacy in PC. Deguelin treatment was observed to inhibit growth and induce apoptosis in two PC cell lines (Bxpc-3 and Panc-1). In addition, it inhibited migration and invasion in these two cell lines. The activation of the hedgehog (Hh) signaling pathway, as well as matrix metalloproteinases (MMP)-2 and MMP-9, was suppressed by deguelin. These results suggest that deguelin may be a potential chemotherapeutic agent for PC, possibly through the suppression of the Hh signaling pathway.

  3. Deguelins, Natural Product Modulators of NF1-Defective Astrocytoma Cell Growth Identified by High-Throughput Screening of Partially Purified Natural Product Extracts.

    PubMed

    Henrich, Curtis J; Cartner, Laura K; Wilson, Jennifer A; Fuller, Richard W; Rizzo, Anthony E; Reilly, Karlyne M; McMahon, James B; Gustafson, Kirk R

    2015-11-25

    A high-throughput screening assay for modulators of Trp53/NF1 mutant astrocytoma cell growth was adapted for use with natural product extracts and applied to a novel collection of prefractionated/partially purified extracts. Screening 68 427 samples identified active fractions from 95 unique extracts, including the terrestrial plant Millettia ichthyotona. Only three of these extracts showed activity in the crude extract form, thus demonstrating the utility of a partial purification approach for natural product screening. The NF1 screening assay was used to guide purification of active compounds from the M. ichthyotona extract, which yielded the two rotenones deguelin (1) and dehydrodeguelin (2). The deguelins have been reported to affect growth of a number of cancer cell lines. They potently inhibited growth of only one of a panel of NF1/Trp53 mutant murine astrocytoma cell lines, possibly related to epigenetic factors, but had no effect on the growth of normal astrocytes. These results suggest the potential utility of deguelins as tools for further investigating NF1 astrocytoma cell growth. These bioprobes were identified only as a result of screening partially purified natural product extracts. PMID:26467198

  4. Synergistic Activity of Deguelin and Fludarabine in Cells from Chronic Lymphocytic Leukemia Patients and in the New Zealand Black Murine Model

    PubMed Central

    Rebolleda, Nerea; Losada-Fernandez, Ignacio; Perez-Chacon, Gema; Castejon, Raquel; Rosado, Silvia; Morado, Marta; Vallejo-Cremades, Maria Teresa; Martinez, Andrea; Vargas-Nuñez, Juan A.

    2016-01-01

    B-cell chronic lymphocytic leukemia (CLL) remains an incurable disease, and despite the improvement achieved by therapeutic regimes developed over the last years still a subset of patients face a rather poor prognosis and will eventually relapse and become refractory to therapy. The natural rotenoid deguelin has been shown to induce apoptosis in several cancer cells and cell lines, including primary human CLL cells, and to act as a chemopreventive agent in animal models of induced carcinogenesis. In this work, we show that deguelin induces apoptosis in vitro in primary human CLL cells and in CLL-like cells from the New Zealand Black (NZB) mouse strain. In both of them, deguelin dowregulates AKT, NFκB and several downstream antiapoptotic proteins (XIAP, cIAP, BCL2, BCL-XL and survivin), activating the mitochondrial pathway of apoptosis. Moreover, deguelin inhibits stromal cell-mediated c-Myc upregulation and resistance to fludarabine, increasing fludarabine induced DNA damage. We further show that deguelin has activity in vivo against NZB CLL-like cells in an experimental model of CLL in young NZB mice transplanted with spleen cells from aged NZB mice with lymphoproliferation. Moreover, the combination of deguelin and fludarabine in this model prolonged the survival of transplanted mice at doses of both compounds that were ineffective when administered individually. These results suggest deguelin could have potential for the treatment of human CLL. PMID:27101369

  5. Selective activity of deguelin identifies therapeutic targets for androgen receptor-positive breast cancer.

    PubMed

    Robles, Andrew J; Cai, Shengxin; Cichewicz, Robert H; Mooberry, Susan L

    2016-06-01

    Triple-negative breast cancers (TNBC) are aggressive malignancies with no effective targeted therapies. Recent gene expression profiling of these heterogeneous cancers and the classification of cell line models now allows for the identification of compounds with selective activities against molecular subtypes of TNBC. The natural product deguelin was found to have selective activity against MDA-MB-453 and SUM-185PE cell lines, which both model the luminal androgen receptor (LAR) subtype of TNBC. Deguelin potently inhibited proliferation of these cells with GI50 values of 30 and 61 nM, in MDA-MB-453 and SUM-185PE cells, respectively. Deguelin had exceptionally high selectivity, 197 to 566-fold, for these cell lines compared to cell lines representing other TNBC subtypes. Deguelin's mechanisms of action were investigated to determine how it produced these potent and selective effects. Our results show that deguelin has dual activities, inhibiting PI3K/Akt/mTOR signaling, and decreasing androgen receptor levels and nuclear localization. Based on these data, we hypothesized that the combination of the mTOR inhibitor rapamycin and the antiandrogen enzalutamide would have efficacy in LAR models. Rapamycin and enzalutamide showed additive effects in MDA-MB-453 cells, and both drugs had potent antitumor efficacy in a LAR xenograft model. These results suggest that the combination of antiandrogens and mTOR inhibitors might be an effective strategy for the treatment of androgen receptor-expressing TNBC. PMID:27255535

  6. BAD, a Proapoptotic Protein, Escapes ERK/RSK Phosphorylation in Deguelin and siRNA-Treated HeLa Cells.

    PubMed

    Hafeez, Samra; Urooj, Mahwish; Saleem, Shamiala; Gillani, Zeeshan; Shaheen, Sumaira; Qazi, Mahmood Husain; Naseer, Muhammad Imran; Iqbal, Zafar; Ansari, Shakeel Ahmed; Haque, Absarul; Asif, Muhammad; Mir, Manzoor Ahmad; Ali, Ashraf; Pushparaj, Peter Natesan; Jamal, Mohammad Sarwar; Rasool, Mahmood

    2016-01-01

    This study has been undertaken to explore the therapeutic effects of deguelin and specific siRNAs in HeLa cells. The data provided clearly show the silencing of ERK 1/2 with siRNAs and inhibition of ERK1/2 with deguelin treatment in HeLa cells. Additionally, we are providing information that deguelin binds directly to anti-apoptotic Bcl-2, Bcl-xl and Mcl-1 in the hydrophobic grooves, thereby releasing BAD and BAX from dimerization with these proteins. This results in increased apoptotic activity through the intrinsic pathway involved in rupture of mitochondrial membrane and release of cytochrome C. Evidence for inhibition of ERK1/2 by deguelin and escape of BAD phosphorylation at serine 112 through ERK/RSK pathway has been further fortified by obtaining similar results by silencing ERK 1/2 each with specific siRNAs. Increase in BAD after treatment with deguelin or siRNAs has been interpreted to mean that deguelin acts through several alternative pathways and therefore can be used as effective therapeutic agent.

  7. Natural products as antimitotic agents.

    PubMed

    Dall'Acqua, Stefano

    2014-01-01

    Natural products still play an important role in the medicinal chemistry, especially in some therapeutic areas. As example more than 60% of currently-used anticancer agents are derives from natural sources including plants, marine organisms or micro-organism. Thus natural products (NP) are an high-impact source of new "lead compounds" or new potential therapeutic agents despite the large development of biotechnology and combinatorial chemistry in the drug discovery and development. Many examples of anticancer drugs as paclitaxel, combretastatin, bryostatin and discodermolide have shown the importance of NP in the anticancer chemotherapy through many years. Many organisms have been studied as sources of drugs namely plants, micro-organisms and marine organisms and the obtained NP can be considered a group of "privileged chemical structures" evolved in nature to interact with other organisms. For this reason NP are a good starting points for pharmaceutical research and also for library design. Tubulin and microtubules are one of the most studied targets for the search of anticancer compounds. Microtubule targeting agents (MTA) also named antimitotic agents are compounds that are able to perturb mitosis but are also able to arrest cell growing during interphase. The anticancer drugs, taxanes and vinca alkaloids have established tubulin as important target in cancer therapy. More recently the vascular disrupting agents (VDA) combretastatin analogues were studied for their antimitotics properties. This review will consider the anti mitotic NP and their potential impact in the development of new therapeutic agents.

  8. Deguelin inhibits the migration and invasion of lung cancer A549 and H460 cells via regulating actin cytoskeleton rearrangement.

    PubMed

    Zhao, Honggang; Jiao, Yan; Zhang, Zuncheng

    2015-01-01

    Deguelin, the main components from Mundulea sericea, was reported to suppress the growth of various cancer cells. However, the effect of Deguelin on tumor cell invasion and metastasis and its mechanism still unclear so far. In this study, we investigated the effects of Deguelin on the cell invasion in human lung cancer A549 and H460 cells. Our results demonstrate that Deguelin can significantly inhibited cell proliferation, cell migration and cell invasion. Moreover, Deguelin could also affected reorganization of the actin cytoskeleton and decreased filopodia and lamellipodia formation. Furthermore, deguelin-treated tumors showed decreased the tumor metastasis related genes such as CD44, MMP2 and MMP9 at protein and mRNA levels and the content of CEA, SCC, NSE, CYFAR21-1. In addition, Deguelin down-regulated protein expression of Rac1 and Rock1, which are impotent in actin cytoskeleton rearrangements and cell motility. Together, our results suggest that Deguelin inhibit tumor growth and metastasis of lung cancer cells and might be a candidate compound for curing lung cancer. PMID:26884827

  9. Natural compounds as anticancer agents: Experimental evidence

    PubMed Central

    Wang, Jiao; Jiang, Yang-Fu

    2012-01-01

    Cancer prevention research has drawn much attention worldwide. It is believed that some types of cancer can be prevented by following a healthy life style. Cancer chemoprevention by either natural or synthetic agents is a promising route towards lowering cancer incidence. In recent years, the concept of cancer chemoprevention has evolved greatly. Experimental studies in animal models demonstrate that the reversal or suppression of premalignant lesions by chemopreventive agents is achievable. Natural occurring agents such as dietary phytochemicals, tea polyphenols and resveratrol show chemopreventive activity in animal models. Moreover, clinical trials for testing the safety and efficacy of a variety of natural agents in preventing or treating human malignancy have been ongoing. Here, we summarize experimental data on the chemopreventive or tumor suppressive effects of several natural compounds including curcumin, (-)-epigallocatechin-3-gallate, resveratrol, indole-3-carbinol, and vitamin D. PMID:24520533

  10. Sweetening agents from natural sources.

    PubMed

    Morris, J A

    1976-01-01

    Sweetness is an important taste sensation to humans. The absence of suitable sweeteners as alternatives to cyclamates and saccharin has led to a renewed interest in sweeteners form natural sources. A brief review of the history of sweetener usage provides a basis for understanding our present heavy consumption of sweet substances. The structure of naturally-occurring compounds possessing a sweet taste range from simple sugars to complex, intensely sweet proteins. The structural types include monoterpenes, diterpenes, triterpenes, flavonoids, steroid saponins, dipeptides, and proteins. Some of these substances are not, strictly-speaking, natural but are derived from natural sources by relatively minor chemical modification. The properties of two non-sweet substances, miraculin and gymnemic acid, are included because of their close relationship to the subject of sweeteners. Miraculin causes sour substances to taste sweet and gymnemic acid selectively blocks sweet taste perception. The second part of the paper presents some of the work on monellin, the intensely sweet protein from "serendipity berries" (Dioscoreophyllum cumminsii). The physico-chemical studies of monellin provide convincing evidence that it is, indeed, a protein. Structural studies using denaturants and specific chemical modifications have provided a beginning of our understanding of the molecular basis of the sweet taste of monellin. PMID:5643

  11. Prevention and Treatment of Colorectal Cancer by Natural Agents From Mother Nature

    PubMed Central

    Aggarwal, Bharat; Prasad, Sahdeo; Sung, Bokyung; Krishnan, Sunil; Guha, Sushovan

    2013-01-01

    Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the United States after cancers of the lung and the breast/prostate. While the incidence of CRC in the United States is among the highest in the world (approximately 52/100,000), its incidence in countries in India is among the lowest (approximately 7/100,000), suggesting that lifestyle factors may play a role in development of the disease. Whereas obesity, excessive alcohol consumption, a high-calorie diet, and a lack of physical activity promote this cancer, evidence indicates that foods containing folates, selenium, Vitamin D, dietary fiber, garlic, milk, calcium, spices, vegetables, and fruits are protective against CRC in humans. Numerous agents from “mother nature” (also called “nutraceuticals,”) that have potential to both prevent and treat CRC have been identified. The most significant discoveries relate to compounds such as cardamonin, celastrol, curcumin, deguelin, diosgenin, thymoquinone, tocotrienol, ursolic acid, and zerumbone. Unlike pharmaceutical drugs, these agents modulate multiple targets, including transcription factors, growth factors, tumor cell survival factors, inflammatory pathways, and invasion and angiogenesis linked closely to CRC. We describe the potential of these dietary agents to suppress the growth of human CRC cells in culture and to inhibit tumor growth in animal models. We also describe clinical trials in which these agents have been tested for efficacy in humans. Because of their safety and affordability, these nutraceuticals provide a novel opportunity for treatment of CRC, an “old age” disease with an “age old” solution. PMID:23814530

  12. Anticancer agents derived from natural cinnamic acids.

    PubMed

    Su, Ping; Shi, Yaling; Wang, Jinfeng; Shen, Xiuxiu; Zhang, Jie

    2015-01-01

    Cancer is the most dangerous disease that causes deaths all over the world. Natural products have afforded a rich source of drugs in a number of therapeutic fields including anticancer agents. Many significant drugs have been derived from natural sources by structural optimization of natural products. Cinnamic acid has gained great interest due to its antiproliferative, antioxidant, antiangiogenic and antitumorigenic potency. Currently it has been observed that cinnamic acid and its analogs such as caffeic acid, sinapic acid, ferulic acid, and isoferulic acid display various pharmacological activities, such as immunomodulation, anti-inflammation, anticancer and antioxidant. They have served to be the major sources of potential leading anticancer compounds. In this review, we focus on the anticancer potency of cinnamic acid derivatives and novel strategies to design these derivatives. We hope this review will be useful for researchers who are interested in developing anticancer agents.

  13. Natural chelating agents for radionuclide decorporation

    DOEpatents

    Premuzic, Eugene T.

    1988-01-01

    This invention relates to the preparation of new, naturally produced chelating agents as well as to the method and resulting chelates of desorbing cultures in a bioavailable form involving Pseudomonas species or other microorganisms. A preferred microorganism is Pseudomonas aeruginosa which forms multiple chelates with thorium in the range of molecular weight 100-1,000 and also forms chelates with uranium of molecular weight in the area of 100-1,000 and 1,000-2,000.

  14. Screening of natural products for antimicrobial agents.

    PubMed

    Silver, L; Bostian, K

    1990-07-01

    Antimicrobial research is geared toward the discovery and development of novel chemical structures such as therapeutic antimicrobial agents. The continuing problem of development of resistance to existing antibacterial agents and the dearth of good antifungal agents motivates this effort toward innovation. Selection of possible new enzyme targets for antibiotic inhibition may be made on theoretical grounds, but it appears premature to select any single, previously unvalidated target for the intensive study required for rational drug design. Instead, a broad screen of chemical entities can be undertaken, dedicated to the discovery of novel antimicrobial inhibitors. A number of target areas are under investigation, including fungal mRNA splicing and bacterial DNA synthesis. A major part of the endeavor is in the historically productive area of natural product screening. To make the best use of natural product resources for the discovery of novel antibiotics, a balance is struct between screening for inhibitors of rationally chosen targets for which clinically useful inhibitors are not yet available, and screening more broadly to ensure that rare activities of unanticipated mode-of-action are not missed.

  15. Naturally derived anti-HIV agents.

    PubMed

    Asres, Kaleab; Seyoum, Ameha; Veeresham, Ciddi; Bucar, Franz; Gibbons, Simon

    2005-07-01

    The urgent need for new anti-HIV/AIDS drugs is a global concern. In addition to obvious economical and commercial hurdles, HIV/AIDS patients are faced with multifarious difficulties associated with the currently approved anti-HIV drugs. Adverse effects, the emergence of drug resistance and the narrow spectrum of activity have limited the therapeutic usefulness of the various reverse transcriptase and protease inhibitors that are currently available on the market. This has driven many scientists to look for new anti-retrovirals with better efficacy, safety and affordability. As has always been the case in the search for cures, natural sources offer great promise. Several natural products, mostly of plant origin have been shown to possess promising activities that could assist in the prevention and/or amelioration of the disease. Many of these anti-HIV agents have other medicinal values as well, which afford them further prospective as novel leads for the development of new drugs that can deal with both the virus and the various disorders that characterize HIV/AIDS. The aim of this review is to report new discoveries and updates pertaining to anti-HIV natural products. In the review anti-HIV agents have been classified according to their chemical classes rather than their target in the HIV replicative cycle, which is the most frequently encountered approach. Perusal of the literature revealed that most of these promising naturally derived anti-HIV compounds are flavonoids, coumarins, terpenoids, alkaloids, polyphenols, polysaccharides or proteins. It is our strong conviction that the results and experiences with many of the anti-HIV natural products will inspire and motivate even more researchers to look for new leads from plants and other natural sources. PMID:16161055

  16. The Hunt for Natural Skin Whitening Agents

    PubMed Central

    Smit, Nico; Vicanova, Jana; Pavel, Stan

    2009-01-01

    Skin whitening products are commercially available for cosmetic purposes in order to obtain a lighter skin appearance. They are also utilized for clinical treatment of pigmentary disorders such as melasma or postinflammatory hyperpigmentation. Whitening agents act at various levels of melanin production in the skin. Many of them are known as competitive inhibitors of tyrosinase, the key enzyme in melanogenesis. Others inhibit the maturation of this enzyme or the transport of pigment granules (melanosomes) from melanocytes to surrounding keratinocytes. In this review we present an overview of (natural) whitening products that may decrease skin pigmentation by their interference with the pigmentary processes. PMID:20054473

  17. NICA: Natural Interaction with a Caring Agent

    NASA Astrophysics Data System (ADS)

    de Carolis, Berardina; Mazzotta, Irene; Novielli, Nicole

    Ambient Intelligence solutions may provide a great opportunity for elderly people to live longer at home. Assistance and care are delegated to the intelligence embedded in the environment. However, besides considering service-oriented response to the user needs, the assistance has to take into account the establishment of social relations. We propose the use of a robot NICA (as the name of the project Natural Interaction with a Caring Agent) acting as a caring assistant that provides a social interface with the smart home services. In this paper, we introduce the general architecture of the robot's "mind" and then we focus on the need to properly react to affective and socially oriented situations.

  18. Natural backbone graft copolymers as suspending agents, dispersing agents, filtrate control agents, and viscosifiers

    SciTech Connect

    Meister, J.J.

    1988-05-01

    Free radical, graft copolymerization of water-soluble monomers onto Kraft, pine lignin produces a natural backgone, graft polymer which functions as a thickening or dispersing agent in water-base, bentonite drilling muds. The complex polymers formed by reacting lignin, calcium chloride, a hydroperoxide, and ethene monomers in anerobic solvent have the structures given in this paper. Synthesis methods, possible synthesis mechanism insights, characterization, properties, and drilling mud tests for these samples are presented in this paper.

  19. Potential Compounds for Oral Cancer Treatment: Resveratrol, Nimbolide, Lovastatin, Bortezomib, Vorinostat, Berberine, Pterostilbene, Deguelin, Andrographolide, and Colchicine

    PubMed Central

    Bundela, Saurabh; Sharma, Anjana; Bisen, Prakash S.

    2015-01-01

    Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine. PMID:26536350

  20. Natural chelating agents for radionuclide decorporation

    DOEpatents

    Premuzic, E.T.

    1985-06-11

    This invention relates to the production of metal-binding compounds useful for the therapy of heavy metal poisoning, for biological mining and for decorporation of radionuclides. The present invention deals with an orderly and effective method of producing new therapeutically effective chelating agents. This method uses challenge biosynthesis for the production of chelating agents that are specific for a particular metal. In this approach, the desired chelating agents are prepared from microorganisms challenged by the metal that the chelating agent is designed to detoxify. This challenge induces the formation of specific or highly selective chelating agents. The present invention involves the use of the challenge biosynthetic method to produce new complexing/chelating agents that are therapeutically useful to detoxify uranium, plutonium, thorium and other toxic metals. The Pseudomonas aeruginosa family of organisms is the referred family of microorganisms to be used in the present invention to produce the new chelating agent because this family is known to elaborate strains resistant to toxic metals.

  1. Modified natural nanoparticles as contrast agents for medical imaging

    PubMed Central

    Cormode, David P.; Jarzyna, Peter A.; Mulder, Willem J. M.; Fayad, Zahi A.

    2009-01-01

    The development of novel and effective contrast agents is one of the drivers of the ongoing improvement in medical imaging. Many of the new agents reported are nanoparticle-based. There are a variety of natural nanoparticles known, e.g. lipoproteins, viruses or ferritin. Natural nanoparticles have advantages as delivery platforms such as biodegradability. In addition, our understanding of natural nanoparticles is quite advanced, allowing their adaptation as contrast agents. They can be labeled with small molecules or ions such as Gd3+ to act as contrast agents for magnetic resonance imaging, 18F to act as positron emission tomography contrast agents or fluorophores to act as contrast agents for fluorescence techniques. Additionally, inorganic nanoparticles such as iron oxide, gold nanoparticles or quantum dots can be incorporated to add further contrast functionality. Furthermore, these natural nanoparticle contrast agents can be rerouted from their natural targets via the attachment of targeting molecules. In this review, we discuss the various modified natural nanoparticles that have been exploited as contrast agents. PMID:19900496

  2. Learning by Communicating in Natural Language with Conversational Agents

    ERIC Educational Resources Information Center

    Graesser, Arthur; Li, Haiying; Forsyth, Carol

    2014-01-01

    Learning is facilitated by conversational interactions both with human tutors and with computer agents that simulate human tutoring and ideal pedagogical strategies. In this article, we describe some intelligent tutoring systems (e.g., AutoTutor) in which agents interact with students in natural language while being sensitive to their cognitive…

  3. Efficacy of some natural compounds as antifungal agents

    PubMed Central

    Vengurlekar, Sudha; Sharma, Rajesh; Trivedi, Piyush

    2012-01-01

    Natural sources have been important for the development of new active molecules for many years. Various small molecules with unique chemical skeleton and potent bioactivities were discovered through various sources like plants, marine products, and microorganisms, etc., which are considered as very important part of the nature. A number of potent antifungals have been originated from various natural sources. This account describes structure and activities of selected agents isolated from various natural sources. PMID:23055634

  4. [Natural purine compounds as radioprotective agents].

    PubMed

    Popova, N R; Gudkov, S V; Bruskov, V I

    2014-01-01

    Purine compounds xanthosine, caffeine, inosine-5'-monophosphate and guanosine-5'-monophosphate in the concentration range of 0.02-1 mmol/L exhibit antioxidant properties in vitro, significantly reducing the formation of hydrogen peroxide and hydroxyl radicals induced by X-rays in aqueous solutions and preventing the formation of 8-oxoguanine in DNA solutions. These compounds neutralize the long-lived protein radicals in vitro induced by radiation. In vivo they exhibit pronounced radiotherapeutic properties, increasing the survival rate of mice up to 50% by intraperitoneal injection (45 mg/kg) after the exposure to a lethal dose of 7 Gy. The tested compounds stimulate hemopoiesis, increasing the number of white blood cells and platelets in the peripheral blood of animals in postradiation period, as well as radiation recovery of DNA damage when administered both before and after irradiation. These purine compounds can be considered as potentially promising preventive and therapeutic agents to reduce the risk of the pathological effects of ionizing radiation on the body of mammals. PMID:25764844

  5. Extending nature's leads: the anticancer agent ellipticine.

    PubMed

    Garbett, Nichola C; Graves, David E

    2004-03-01

    The natural plant product ellipticine was isolated in 1959 from the Australian evergreen tree of the Apocynaceae family. This compound was found to be an extremely promising anticancer drug. The planar polycyclic structure was found to interact with DNA through intercalation, exhibiting a high DNA binding affinity (10(6) M(-1)). The presence of protonatable ring nitrogens distinguished ellipticine from other simple intercalators. Both monocationic and uncharged species were found to be present under physiological conditions. The positive charge stabilized the binding of ellipticine to nucleic acids, while the more lipophilic uncharged compound was shown to readily penetrate membrane barriers. The structural nature of these compounds offers a plausible basis for the implication of multiple modes of action, including DNA binding, interactions with membrane barriers, oxidative bioactivation and modification of enzyme function; most notably that of topoisomerase II and telomerase. Pharmacologically, a number of toxic side effects have been shown to be problematic, but the amenability of ellipticine towards systematic structural modification has permitted the extensive application of rational drug design. A number of successful ellipticine analogs have been designed and synthesized with improved toxicities and anticancer activities. More recently the synthetic focus has broadened to include the design of hybrid compounds, as well as drug delivery conjugates. Considerable research efforts have been directed towards gaining a greater understanding of the mechanism of action of these drugs that will aid further in the optimization of drug design.

  6. [Natural bioactive agents in liver therapy].

    PubMed

    Blázovics, Anna

    2015-11-22

    Medical science alongside with other sciences, aiming to preserve health and combat diseases, has evolved significantly since the late 1930s. It has reached incredible results and opened up unpredicted perspectives for future generations to come. From the 1980s significant results also emerged from researching natural plant active ingredients for the prevention of damage from free radicals which were discovered in different symptoms. One of the important areas of research is the recognition of significant bioactive molecules from the aspects of food consumption, alongside the detection of their effect in the context of their structure. It is also important that by possessing these data it is possible to develop correct food consumption habits, especially for people who are suffering from diseases. Through the decades we came a long way from folk medicine observations to molecular, biological justification of effect mechanisms. PMID:26568101

  7. A novel antitumor activity of deguelin targeting the insulin-like growth factor (IGF) receptor pathway via up-regulation of IGF-binding protein-3 expression in breast cancer

    PubMed Central

    Suh, Young-Ah; Kim, Jai-Hyun; Sung, Myung A; Boo, Hye-Jin; Yun, Hye Jeong; Lee, Sun-Hye; Lee, Hyo-Jong; Suh, Young-Ger; Kim, Kyu-Won; Lee, Ho-Young

    2013-01-01

    In this study, we investigated the antitumor effects of deguelin in several human breast cancer cells in vitro and in vivo. Deguelin inhibited cell viability and the anchorage-dependent and anchorage-independent colony formation of triple-negative (MDA-MB-231 and MDA-MB-468) and triple-positive (MCF-7) breast cancer cells, and it significantly reduced the growth of MCF-7 cell xenograft tumors. The induction of apoptosis, inhibition of insulin-like growth factor-1 receptor (IGF-1R) signaling activation, and up-regulation of IGF-binding protein-3 (IGFBP-3) expression may be associated with deguelin-mediated antitumor effects. Our findings suggest a potential therapeutic use for deguelin in patients with triple-negative breast cancer and for those with breast cancers who are sensitive to endocrine- and HER2-targeted therapies. PMID:23348700

  8. Tuberculosis and nature's pharmacy of putative anti-tuberculosis agents.

    PubMed

    Chinsembu, Kazhila C

    2016-01-01

    Due to the growing problem of drug resistant Mycobacterium tuberculosis strains, coupled with the twinning of tuberculosis (TB) to human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), the burden of TB is now difficult to manage. Therefore, new antimycobacterial agents are being sought from natural sources. This review focuses on natural antimycobacterial agents from endophytes and medicinal plants of Africa, Europe, Asia, South America and Canada. In the countries mentioned in this review, numerous plant species display putative anti-TB activity. Several antimycobacterial chemical compounds have also been isolated, including: ellagitannin punicalagin, allicin, anthraquinone glycosides, iridoids, phenylpropanoids, beta-sitosterol, galanthimine, crinine, friedelin, gallic acid, ellagic acids, anthocyanidin, taraxerol, termilignan B, arjunic acid, glucopyranosides, 1-epicatechol, leucopelargonidol, hydroxybenzoic acids, benzophenanthridine alkaloids, neolignans, and decarine. These compounds may provide leads to novel and more efficacious drugs to lessen the global burden of TB and drug-resistant M. tuberculosis strains. If there is a long-term remedy for TB, it must lie in nature's pharmacy of putative antimycobacterial agents.

  9. Tuberculosis and nature's pharmacy of putative anti-tuberculosis agents.

    PubMed

    Chinsembu, Kazhila C

    2016-01-01

    Due to the growing problem of drug resistant Mycobacterium tuberculosis strains, coupled with the twinning of tuberculosis (TB) to human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), the burden of TB is now difficult to manage. Therefore, new antimycobacterial agents are being sought from natural sources. This review focuses on natural antimycobacterial agents from endophytes and medicinal plants of Africa, Europe, Asia, South America and Canada. In the countries mentioned in this review, numerous plant species display putative anti-TB activity. Several antimycobacterial chemical compounds have also been isolated, including: ellagitannin punicalagin, allicin, anthraquinone glycosides, iridoids, phenylpropanoids, beta-sitosterol, galanthimine, crinine, friedelin, gallic acid, ellagic acids, anthocyanidin, taraxerol, termilignan B, arjunic acid, glucopyranosides, 1-epicatechol, leucopelargonidol, hydroxybenzoic acids, benzophenanthridine alkaloids, neolignans, and decarine. These compounds may provide leads to novel and more efficacious drugs to lessen the global burden of TB and drug-resistant M. tuberculosis strains. If there is a long-term remedy for TB, it must lie in nature's pharmacy of putative antimycobacterial agents. PMID:26464047

  10. Natural Products as a Source for Antileishmanial and Antitrypanosomal Agents.

    PubMed

    Scotti, Marcus Tullius; Scotti, Luciana; Ishiki, Hamilton; Ribeiro, Frederico Fávaro; Cruz, Rayssa Marques Duarte da; Oliveira, Michelle Pedrosa de; Mendonça, Francisco Jaime Bezerra

    2016-01-01

    Natural products are compounds extracted from plants, marine organisms, fungi or bacteria. Many researches for new drugs are based on these natural molecules, mainly by beneficial effects on health, health, efficacy, and therapeutic safety. Leishmaniosis, Chagas disease and African sleeping sickness are neglected diseases caused by the Leishmania and Trypanosoma ssp. parasites. These infections mainly affect population of developing countries; they have different symptoms, and may often lead to death. The therapeutic drugs available to treat these diseases are either obsolete, toxic, or have questionable efficacy, possibly through encountering resistance. Discovery of new, safe, effective, and affordable molecules is urgently needed. Natural organisms, as marine metabolites, alkaloids, flavonoids, steroids, terpene and coumarins provide innumerable molecules with the potential to treat these diseases. This study examines studies of natural bioactive compounds as antileishmanial and antitrypanosomal agents. PMID:27682867

  11. Development of non-natural flavanones as antimicrobial agents.

    PubMed

    Fowler, Zachary L; Shah, Karan; Panepinto, John C; Jacobs, Amy; Koffas, Mattheos A G

    2011-01-01

    With growing concerns over multidrug resistance microorganisms, particularly strains of bacteria and fungi, evolving to become resistant to the antimicrobial agents used against them, the identification of new molecular targets becomes paramount for novel treatment options. Recently, the use of new treatments containing multiple active ingredients has been shown to increase the effectiveness of existing molecules for some infections, often with these added compounds enabling the transport of a toxic molecule into the infecting species. Flavonoids are among the most abundant plant secondary metabolites and have been shown to have natural abilities as microbial deterrents and anti-infection agents in plants. Combining these ideas we first sought to investigate the potency of natural flavonoids in the presence of efflux pump inhibitors to limit Escherichia coli growth. Then we used the natural flavonoid scaffold to synthesize non-natural flavanone molecules and further evaluate their antimicrobial efficacy on Escherichia coli, Bacillus subtilis and the fungal pathogens Cryptococcus neoformans and Aspergillus fumigatus. Of those screened, we identified the synthetic molecule 4-chloro-flavanone as the most potent antimicrobial compound with a MIC value of 70 µg/mL in E. coli when combined with the inhibitor Phe-Arg-ß-naphthylamide, and MICs of 30 µg/mL in S. cerevesiae and 30 µg/mL in C. neoformans when used alone. Through this study we have demonstrated that combinatorial synthesis of non-natural flavonones can identify novel antimicrobial agents with activity against bacteria and fungi but with minimal toxicity to human cells.

  12. Essential oils as natural food antimicrobial agents: a review.

    PubMed

    Vergis, Jess; Gokulakrishnan, P; Agarwal, R K; Kumar, Ashok

    2015-01-01

    Food-borne illnesses pose a real scourge in the present scenario as the consumerism of packaged food has increased to a great extend. Pathogens entering the packaged foods may survive longer, which needs a check. Antimicrobial agents either alone or in combination are added to the food or packaging materials for this purpose. Exploiting the antimicrobial property, essential oils are considered as a "natural" remedy to this problem other than its flavoring property instead of using synthetic agents. The essential oils are well known for its antibacterial, antiviral, antimycotic, antiparasitic, and antioxidant properties due to the presence of phenolic functional group. Gram-positive organisms are found more susceptible to the action of the essential oils. Essential oils improve the shelf-life of packaged products, control the microbial growth, and unriddle the consumer concerns regarding the use of chemical preservatives. This review is intended to provide an overview of the essential oils and their role as natural antimicrobial agents in the food industry.

  13. Essential oils as natural food antimicrobial agents: a review.

    PubMed

    Vergis, Jess; Gokulakrishnan, P; Agarwal, R K; Kumar, Ashok

    2015-01-01

    Food-borne illnesses pose a real scourge in the present scenario as the consumerism of packaged food has increased to a great extend. Pathogens entering the packaged foods may survive longer, which needs a check. Antimicrobial agents either alone or in combination are added to the food or packaging materials for this purpose. Exploiting the antimicrobial property, essential oils are considered as a "natural" remedy to this problem other than its flavoring property instead of using synthetic agents. The essential oils are well known for its antibacterial, antiviral, antimycotic, antiparasitic, and antioxidant properties due to the presence of phenolic functional group. Gram-positive organisms are found more susceptible to the action of the essential oils. Essential oils improve the shelf-life of packaged products, control the microbial growth, and unriddle the consumer concerns regarding the use of chemical preservatives. This review is intended to provide an overview of the essential oils and their role as natural antimicrobial agents in the food industry. PMID:24915323

  14. Intelligent agents as a basis for natural language interfaces

    SciTech Connect

    Chin, D.N.

    1987-01-01

    Typical natural-language interfaces respond passively to the users's commands and queries. They cannot volunteer information, correction user misconceptions, or reject unethical requests. In order to do these things, a system must be an intelligent agent. UC (UNIX Consultant), a natural language system that helps the user solve problems in using the UNIX operating system, is such an intelligent agent. The agent component of UC in UCEgo. UCEgo provides UC with its own goals and plans. By adopting different goals in different situations, UCEgo creates and executes different plans, enabling it to interact appropriately with the user. UCEgo adopts goals from its themes, adopts subgoals during planning, and adopts metagoals for dealing with goal interactions. It also adopts goals when it notices that the user either lacks necessary knowledge, or has incorrect beliefs. In these cases, UCEgo plans to volunteer information or correct the user's misconception as appropriate. The user's knowledge and beliefs are modeled by the KNOME (KNOwledge Model of Expertise) component of UC. KNOME is a double-stereotype system which categorizes users by expertise and categorizes UNIX facts by difficulty.

  15. Targeting Reactive Carbonyl Species with Natural Sequestering Agents.

    PubMed

    Hwang, Sung Won; Lee, Yoon-Mi; Aldini, Giancarlo; Yeum, Kyung-Jin

    2016-01-01

    Reactive carbonyl species generated by the oxidation of polyunsaturated fatty acids and sugars are highly reactive due to their electrophilic nature, and are able to easily react with the nucleophilic sites of proteins as well as DNA causing cellular dysfunction. Levels of reactive carbonyl species and their reaction products have been reported to be elevated in various chronic diseases, including metabolic disorders and neurodegenerative diseases. In an effort to identify sequestering agents for reactive carbonyl species, various analytical techniques such as spectrophotometry, high performance liquid chromatography, western blot, and mass spectrometry have been utilized. In particular, recent advances using a novel high resolution mass spectrometry approach allows screening of complex mixtures such as natural products for their sequestering ability of reactive carbonyl species. To overcome the limited bioavailability and bioefficacy of natural products, new techniques using nanoparticles and nanocarriers may offer a new attractive strategy for increased in vivo utilization and targeted delivery of bioactives. PMID:26927058

  16. Natural Compounds as Therapeutic Agents in the Treatment Cystic Fibrosis

    PubMed Central

    Dey, Isha; Shah, Kalpit; Bradbury, Neil A

    2016-01-01

    The recent FDA approval of two drugs to treat the basic defect in cystic fibrosis has given hope to patients and their families battling this devastating disease. Over many years, with heavy financial investment from Vertex Pharmaceuticals and the Cystic Fibrosis Foundation, pre-clinical evaluation of thousands of synthetic drugs resulted in the production of Kalydeco and Orkambi. Yet, despite the success of this endeavor, many other compounds have been proposed as therapeutic agents in the treatment of CF. Of note, several of these compounds are naturally occurring, and are present in spices from the grocery store and over the counter preparations in health food stores. In this short review, we look at three such compounds, genistein, curcumin, and resveratrol, and evaluate the scientific support for their use as therapeutic agents in the treatment of patients with CF. PMID:27081574

  17. Degradability of fluorapatite-leucite ceramics in naturally acidic agents.

    PubMed

    Kukiattrakoon, Boonlert; Hengtrakool, Chanothai; Kedjarune-Leggat, Ureporn

    2010-10-01

    This study was conducted to evaluate the titratable acidity and effect of naturally acidic agents on the surface microhardness, elemental composition, and surface morphology of fluorapatite-leucite ceramics. One hundred and ten ceramic disks (IPS d.SIGN), 12.0 mm in diameter and 2.0 mm in thickness, were fabricated. Before immersion, the baseline data of Vickers microhardness and elemental composition were recorded. Four groups were immersed in acidic agents (citrate buffer solution, green mango juice, and pineapple juice) and deionized water (control) at 37ºC for 168 hours, whereas one group was immersed in 4% acetic acid at 80ºC for 168 hours. After immersion, specimens were evaluated and data were analyzed using one-way repeated ANOVA and Tukey's test (α=0.05). Microhardness values significantly decreased after immersion (p<0.05). In terms of elemental composition, the weight percentages of silicon, potassium, aluminum, and sodium also decreased after immersion (p<0.05). Results of this study showed that fluorapatite-leucite ceramics were affected by long-term immersion in acidic agents.

  18. Alkaloids Isolated from Natural Herbs as the Anticancer Agents

    PubMed Central

    Lu, Jin-Jian; Bao, Jiao-Lin; Chen, Xiu-Ping; Huang, Min; Wang, Yi-Tao

    2012-01-01

    Alkaloids are important chemical compounds that serve as a rich reservoir for drug discovery. Several alkaloids isolated from natural herbs exhibit antiproliferation and antimetastasis effects on various types of cancers both in vitro and in vivo. Alkaloids, such as camptothecin and vinblastine, have already been successfully developed into anticancer drugs. This paper focuses on the naturally derived alkaloids with prospective anticancer properties, such as berberine, evodiamine, matrine, piperine, sanguinarine, and tetrandrine, and summarizes the mechanisms of action of these compounds. Based on the information in the literature that is summarized in this paper, the use of alkaloids as anticancer agents is very promising, but more research and clinical trials are necessary before final recommendations on specific alkaloids can be made. PMID:22988474

  19. Targeting Microtubules by Natural Agents for Cancer Therapy

    PubMed Central

    Mukhtar, Eiman; Adhami, Vaqar Mustafa; Mukhtar, Hasan

    2014-01-01

    Natural compounds that target microtubules and disrupt the normal function of the mitotic spindle have proven to be one of the best classes of cancer chemotherapeutic drugs available in clinics to date. There is increasing evidence showing that even minor alteration of microtubule dynamics can engage the spindle checkpoint, arresting cell cycle progression at mitosis and subsequently leading to cell death. Our improved understanding of tumor biology and our continued appreciation for what the microtubule target agents (MTAs) can do has helped pave the way for a new era in the treatment of cancer. The effectiveness of these agents for cancer therapy has been impaired, however, by various side effects and drug resistance. Several new MTAs have shown potent activity against the proliferation of various cancer cells, including resistance to the existing MTAs. Sustained investigation of the mechanisms of action of MTAs, development and discovery of new drugs, and exploring new treatment strategies that reduce side effects and circumvent drug resistance could provide more effective therapeutic options for cancer patients. This review focuses on the successful cancer chemotherapy from natural compounds in clinical settings and the challenges that may abort their usefulness. PMID:24435445

  20. CHARACTERIZATION OF CASEINS CROSSLINKED BY A NATURALLY OCCURRING CROSSLINKING AGENT-GENIPIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing economic and environmental pressures demand more effective utilization of natural resources. Genipin, a naturally occurring crosslinking agent obtained from the fruit of Gardenia jasminoides, has recently attracted much attention due to its low cytotoxicity compared to traditional crossli...

  1. Anti-Enterovirus 71 Agents of Natural Products.

    PubMed

    Wang, Liyan; Wang, Junfeng; Wang, Lishu; Ma, Shurong; Liu, Yonghong

    2015-01-01

    This review, with 42 references, presents the fascinating area of anti-enterovirus 71 natural products over the last three decades for the first time. It covers literature published from 2005-2015 and refers to compounds isolated from biogenic sources. In total, 58 naturally-occurring anti-EV71 compounds are recorded. PMID:26370955

  2. Anti-Enterovirus 71 Agents of Natural Products.

    PubMed

    Wang, Liyan; Wang, Junfeng; Wang, Lishu; Ma, Shurong; Liu, Yonghong

    2015-01-01

    This review, with 42 references, presents the fascinating area of anti-enterovirus 71 natural products over the last three decades for the first time. It covers literature published from 2005-2015 and refers to compounds isolated from biogenic sources. In total, 58 naturally-occurring anti-EV71 compounds are recorded.

  3. Natural Organohalogens: A New Frontier for Medicinal Agents?

    NASA Astrophysics Data System (ADS)

    Gribble, Gordon W.

    2004-10-01

    More than 4000 naturally occurring organohalogen compounds are known. These include a relatively small number of abiogenic organohalogens from volcanoes, forest fires, geothermal processes, and meteorites, and a very large number of biogenic organohalogens produced by myriad living organisms as part of their chemical makeup that serve as hormones, pheromones, repellents, and natural pesticides. From the chemically simple methyl chloride, methyl bromide, and chloroform to the structurally complex vancomycin, pyrroindomycin, and bastadins, the diversity of these organohalogens is unsurpassed among natural products. Most natural organohalogens contain chlorine (2300) or bromine (2100), but a significant number contain iodine (120) or fluorine (30). Several hundred marine natural products contain both chlorine and bromine. The present article focuses on newly discovered biogenic organohalogens, with an emphasis on those biologically active examples from marine organisms, bacteria, terrestrial plants, and higher life forms including humans.

  4. Novel food packaging systems with natural antimicrobial agents.

    PubMed

    Irkin, Reyhan; Esmer, Ozlem Kizilirmak

    2015-10-01

    A new type of packaging that combines food packaging materials with antimicrobial substances to control microbial surface contamination of foods to enhance product microbial safety and to extend shelf-life is attracting interest in the packaging industry. Several antimicrobial compounds can be combined with different types of packaging materials. But in recent years, since consumer demand for natural food ingredients has increased because of safety and availability, these natural compounds are beginning to replace the chemical additives in foods and are perceived to be safer and claimed to alleviate safety concerns. Recent research studies are mainly focused on the application of natural antimicrobials in food packaging system. Biologically derived compounds like bacteriocins, phytochemicals, enzymes can be used in antimicrobial food packaging. The aim of this review is to give an overview of most important knowledge about application of natural antimicrobial packagings with model food systems and their antimicrobial effects on food products. PMID:26396358

  5. Emerging natural threats and the deliberate use of biological agents.

    PubMed

    Greenberg, Michael I; Marty, Aileen M

    2006-06-01

    Over the past several years there has been an increasing awareness and interest by the medical community, the media, and government at all levels regarding the need to plan for and defend against biological weapons. This article offers an overview of various new and emerging natural biological threats.

  6. Natural Organohalogens: A New Frontier for Medicinal Agents?

    ERIC Educational Resources Information Center

    Gribble, Gordon W.

    2004-01-01

    Newly discovered biogenic organo halogens with an emphasis on the biologically active examples from marine organisms, bacteria, terrestrial plants and higher life forms, including humans, are focused. Organohalogen compounds represent a valuable and expanding class of natural products, in many cases boasting exceptional biological activity.

  7. Bioactive agents from natural sources: trends in discovery and application.

    PubMed

    Grabley, S; Thiericke, R

    1999-01-01

    About 30% of the worldwide sales of drugs are based on natural products. Though recombinant proteins and peptides account for increasing sales rates, the superiority of low-molecular mass compounds in human diseases therapy remains undisputed mainly due to more favorable compliance and bioavailability properties. In the past, new therapeutic approaches often derived from natural products. Numerous examples from medicine impressively demonstrate the innovative potential of natural compounds and their impact on progress in drug discovery and development. However, natural products are currently undergoing a phase of reduced attention in drug discovery because of the enormous effort which is necessary to isolate the active principles and to elucidate their structures. To meet the demand of several hundred thousands of test samples that have to be submitted to high-throughput screening (HTS) new strategies in natural product chemistry are necessary in order to compete successfully with combinatorial chemistry. Today, pharmaceutical companies have to spend approximately US $350 million to develop a new drug. Currently, approaches to improve and accelerate the joint drug discovery and development process are expected to arise mainly from innovation in drug target elucidation and lead finding. Breakthroughs in molecular biology, cell biology, and genetic engineering in the 1980 s gave access to understanding diseases on the molecular or on the gene level. Subsequently, constructing novel target directed screening assay systems of promising therapeutic significance, automation, and miniaturization resulted in HTS approaches changing the industrial drug discovery process drastically. Furthermore, elucidation of the human genome will provide access to a dramatically increased number of new potential drug targets that have to be evaluated for drug discovery. HTS enables the testing of an increasing number of samples. Therefore, new concepts to generate large compound

  8. Quercetin as natural stabilizing agent for bio-polymer

    SciTech Connect

    Morici, Elisabetta; Arrigo, Rossella; Dintcheva, Nadka Tzankova

    2014-05-15

    The introduction of antioxidants in polymers is the main way to prevent or delay the degradation process. In particular natural antioxidants receive attention in the food industry also because of their presumed safety. In this work bio-polymers, i.e. a commercial starch-based polymer (Mater-Bi®) and a bio-polyester (PLA), and a bio-polyether (PEO) were additivated with quercetin, a natural flavonoid antioxidants, in order to formulate bio-based films for ecosustainable packaging and outdoor applications. The photo-oxidation behavior of unstabilized and quercetin stabilized films was analyzed and compared with the behavior of films additivated with a commercial synthetic light stabilizer. The quercetin is able to slow down the photo-degradation rate of all bio-polymeric films investigated in similar way to the synthetic stabilizer.

  9. Quercetin as natural stabilizing agent for bio-polymer

    NASA Astrophysics Data System (ADS)

    Morici, Elisabetta; Arrigo, Rossella; Dintcheva, Nadka Tzankova

    2014-05-01

    The introduction of antioxidants in polymers is the main way to prevent or delay the degradation process. In particular natural antioxidants receive attention in the food industry also because of their presumed safety. In this work bio-polymers, i.e. a commercial starch-based polymer (Mater-Bi®) and a bio-polyester (PLA), and a bio-polyether (PEO) were additivated with quercetin, a natural flavonoid antioxidants, in order to formulate bio-based films for ecosustainable packaging and outdoor applications. The photo-oxidation behavior of unstabilized and quercetin stabilized films was analyzed and compared with the behavior of films additivated with a commercial synthetic light stabilizer. The quercetin is able to slow down the photo-degradation rate of all bio-polymeric films investigated in similar way to the synthetic stabilizer.

  10. Natural anti-inflammatory agents for pain relief

    PubMed Central

    Maroon, Joseph C.; Bost, Jeffrey W.; Maroon, Adara

    2010-01-01

    The use of both over-the-counter and prescription nonsteroidal medications is frequently recommended in a typical neurosurgical practice. But persistent long-term use safety concerns must be considered when prescribing these medications for chronic and degenerative pain conditions. This article is a literature review of the biochemical pathways of inflammatory pain, the potentially serious side effects of nonsteroidal drugs and commonly used and clinically studied natural alternative anti-inflammatory supplements. Although nonsteroidal medications can be effective, herbs and dietary supplements may offer a safer, and often an effective, alternative treatment for pain relief, especially for long-term use. PMID:21206541

  11. Hallucinogens and dissociative agents naturally growing in the United States.

    PubMed

    Halpern, John H

    2004-05-01

    It is usually believed that drugs of abuse are smuggled into the United States or are clandestinely produced for illicit distribution. Less well known is that many hallucinogens and dissociative agents can be obtained from plants and fungi growing wild or in gardens. Some of these botanical sources can be located throughout the United States; others have a more narrow distribution. This article reviews plants containing N,N-dimethyltryptamine, reversible type A monoamine oxidase inhibitors (MAOI), lysergic acid amide, the anticholinergic drugs atropine and scopolamine, or the diterpene salvinorin-A (Salvia divinorum). Also reviewed are mescaline-containing cacti, psilocybin/psilocin-containing mushrooms, and the Amanita muscaria and Amanita pantherina mushrooms that contain muscimol and ibotenic acid. Dangerous misidentification is most common with the mushrooms, but even a novice forager can quickly learn how to properly identify and prepare for ingestion many of these plants. Moreover, through the ever-expanding dissemination of information via the Internet, this knowledge is being obtained and acted upon by more and more individuals. This general overview includes information on the geographical range, drug content, preparation, intoxication, and the special health risks associated with some of these plants. Information is also offered on the unique issue of when bona fide religions use such plants as sacraments in the United States. In addition to the Native American Church's (NAC) longstanding right to peyote, two religions of Brazilian origin, the Santo Daime and the Uniao do Vegetal (UDV), are seeking legal protection in the United States for their use of sacramental dimethyltryptamine-containing "ayahuasca."

  12. Natural Forces as Agents: Reconceptualizing the Animate-Inanimate Distinction

    PubMed Central

    Lowder, Matthew W.; Gordon, Peter C.

    2014-01-01

    Research spanning multiple domains of psychology has demonstrated preferential processing of animate as compared to inanimate entities—a pattern that is commonly explained as due to evolutionarily adaptive behavior. Forces of nature represent a class of entities that are semantically inanimate but which behave as if they are animate in that they possess the ability to initiate movement and cause actions. We report an eye-tracking experiment demonstrating that natural forces are processed like animate entities during online sentence processing: they are easier to integrate with action verbs than instruments, and this effect is mediated by sentence structure. The results suggest that many cognitive and linguistic phenomena that have previously been attributed to animacy may be more appropriately attributed to perceived agency. To the extent that this is so, the cognitive potency of animate entities may not be due to vigilant monitoring of the environment for unpredictable events as argued by evolutionary psychologists but instead may be more adequately explained as reflecting a cognitive and linguistic focus on causal explanations that is adaptive because it increases the predictability of events. PMID:25497518

  13. SMART II+ : the spot market agent research tool version 2.0 plus natural gas.

    SciTech Connect

    North, M. J. N.

    2000-12-14

    Complex Adaptive Systems (CAS) can be applied to investigate complex infrastructure interdependencies including those between the electric power and natural gas markets. The electric power and natural gas markets are undergoing fundamental transformations. These transformations include major changes in electric generator fuel sources. Electric generators that use natural gas as a fuel source are rapidly gaining market share. Electric generators using natural gas introduce direct interdependency between the electric power and natural gas markets. The interdependencies between the electric power and natural gas markets introduced by these generators can be investigated using the emergent behavior of CAS model agents.

  14. Pectin functionalized with natural fatty acids as antimicrobial agent.

    PubMed

    Calce, Enrica; Mignogna, Eleonora; Bugatti, Valeria; Galdiero, Massimiliano; Vittoria, Vittoria; De Luca, Stefania

    2014-07-01

    Several pectin derivatives were prepared by chemical modifications of the polysaccharide with natural fatty acids. The obtained biodegradable pectin-based materials, pectin-linoleate, pectin-oleate and pectin-palmitate, were investigated for their antimicrobial activity against several bacterial strains, Staphylococcus aureus and Escherichia coli. Good results were obtained for pectin-oleate and pectin-linoleate, which inhibit the growth of the selected microorganisms by 50-70%. They exert the better antimicrobial activity against S. aureus. Subsequently, the pectin-oleate and the pectin-linoleate samples were coated on polyethylene films and were assessed for their capacity to capture the oxygen molecules, reducing its penetration into the polymeric support. These results confirmed a possible application of the new materials in the field of active food packaging.

  15. Natural product inhibitors of ocular angiogenesis

    PubMed Central

    Sulaiman, Rania S.; Basavarajappa, Halesha D.; Corson, Timothy W.

    2014-01-01

    Natural products are characterized by high chemical diversity and biochemical specificity; therefore, they are appealing as lead compounds for drug discovery. Given the importance of angiogenesis to many pathologies, numerous natural products have been explored as potential anti-angiogenic drugs. Ocular angiogenesis underlies blinding eye diseases such as retinopathy of prematurity (ROP) in children, proliferative diabetic retinopathy (DR) in adults of working age, and age-related macular degeneration (AMD) in the elderly. Despite the presence of effective therapy in many cases, these diseases are still a significant health burden. Anti-VEGF biologics are the standard of care, but may cause ocular or systemic side effects after intraocular administration and patients may be refractory. Many anti-angiogenic compounds inhibit tumor growth and metastasis alone or in combination therapy, but a more select subset of them has been tested in the context of ocular neovascular diseases. Here, we review the promise of natural products as anti-angiogenic agents, with a specific focus on retinal and choroidal neovascularization. The multifunctional curcumin and the chalcone isoliquiritigenin have demonstrated promising anti-angiogenic effects in mouse models of DR and choroidal neovascularization (CNV) respectively. The homoisoflavanone cremastranone and the flavonoid deguelin have been shown to inhibit ocular neovascularization in more than one disease model. The isoflavone genistein and the flavone apigenin on the other hand are showing potential in the prevention of retinal and choroidal angiogenesis with long-term administration. Many other products with antiangiogenic potential in vitro such as the lactone withaferin A, the flavonol quercetin, and the stilbenoid combretastatin A4 are awaiting investigation in different ocular disease relevant animal models. These natural products may serve as lead compounds for the design of more specific, efficacious, and affordable

  16. Natural product inhibitors of ocular angiogenesis.

    PubMed

    Sulaiman, Rania S; Basavarajappa, Halesha D; Corson, Timothy W

    2014-12-01

    Natural products are characterized by high chemical diversity and biochemical specificity; therefore, they are appealing as lead compounds for drug discovery. Given the importance of angiogenesis to many pathologies, numerous natural products have been explored as potential anti-angiogenic drugs. Ocular angiogenesis underlies blinding eye diseases such as retinopathy of prematurity (ROP) in children, proliferative diabetic retinopathy (DR) in adults of working age, and age-related macular degeneration (AMD) in the elderly. Despite the presence of effective therapy in many cases, these diseases are still a significant health burden. Anti-VEGF biologics are the standard of care, but may cause ocular or systemic side effects after intraocular administration and patients may be refractory. Many anti-angiogenic compounds inhibit tumor growth and metastasis alone or in combination therapy, but a more select subset of them has been tested in the context of ocular neovascular diseases. Here, we review the promise of natural products as anti-angiogenic agents, with a specific focus on retinal and choroidal neovascularization. The multifunctional curcumin and the chalcone isoliquiritigenin have demonstrated promising anti-angiogenic effects in mouse models of DR and choroidal neovascularization (CNV) respectively. The homoisoflavanone cremastranone and the flavonoid deguelin have been shown to inhibit ocular neovascularization in more than one disease model. The isoflavone genistein and the flavone apigenin on the other hand are showing potential in the prevention of retinal and choroidal angiogenesis with long-term administration. Many other products with anti-angiogenic potential in vitro such as the lactone withaferin A, the flavonol quercetin, and the stilbenoid combretastatin A4 are awaiting investigation in different ocular disease-relevant animal models. These natural products may serve as lead compounds for the design of more specific, efficacious, and affordable

  17. Natural Products as a Vital Source for the Discovery of Cancer Chemotherapeutic and Chemopreventive Agents.

    PubMed

    Cragg, Gordon M; Pezzuto, John M

    2016-01-01

    Throughout history, natural products have played a dominant role in the treatment of human ailments. For example, the legendary discovery of penicillin transformed global existence. Presently, natural products comprise a large portion of current-day pharmaceutical agents, most notably in the area of cancer therapy. Examples include Taxol, vinblastine, and camptothecin. These structurally unique agents function by novel mechanisms of action; isolation from natural sources is the only plausible method that could have led to their discovery. In addition to terrestrial plants as sources for starting materials, the marine environment (e.g., ecteinascidin 743, halichondrin B, and dolastatins), microbes (e.g., bleomycin, doxorubicin, and staurosporin), and slime molds (e.g., epothilone B) have yielded remarkable cancer chemotherapeutic agents. Irrespective of these advances, cancer remains a leading cause of death worldwide. Undoubtedly, the prevention of human cancer is highly preferable to treatment. Cancer chemoprevention, the use of vaccines or pharmaceutical agents to inhibit, retard, or reverse the process of carcinogenesis, is another important approach for easing this formidable public health burden. Similar to cancer chemotherapeutic agents, natural products play an important role in this field. There are many examples, including dietary phytochemicals such as sulforaphane and phenethyl isothiocyanate (cruciferous vegetables) and resveratrol (grapes and grape products). Overall, natural product research is a powerful approach for discovering biologically active compounds with unique structures and mechanisms of action. Given the unfathomable diversity of nature, it is reasonable to suggest that chemical leads can be generated that are capable of interacting with most or possibly all therapeutic targets. PMID:26679767

  18. Synergistic Effects of Dietary Natural Products as Anti-Prostate Cancer Agents.

    PubMed

    Vue, Bao; Zhang, Sheng; Chen, Qiao-Hong

    2015-12-01

    This review is to describe synergistic effects of various combinations of dietary natural products including curcumin, quercetin, soybean isoflavones, silibinin, and EGCG that have potential for the treatment of prostate cancer. These data can provide valuable insights into the future rational design and development of synergistic and/or hybrid agents for potential treatment of prostate cancer. PMID:26882694

  19. Natural infection of small mammal species in Minnesota with the agent of human granulocytic ehrlichiosis.

    PubMed

    Walls, J J; Greig, B; Neitzel, D F; Dumler, J S

    1997-04-01

    The natural reservoirs for the agent of human granulocytic ehrlichiosis (HGE) are suspected to be the small mammals that host immature stages of Ixodes scapularis ticks. To determine if such small mammals are naturally infected, we collected blood and serum samples from small mammal species in rural and suburban areas of Minneapolis and St. Paul, Minn. Samples were collected from white-footed mice (Peromyscus leucopus), eastern chipmunks (Tamias striatus), southern red-backed voles (Clethrionomys gapperi), and insectivorous shrews (Blarina brevicauda and Sorex cinereus). Blood samples were tested by PCR for active infection with the HGE agent, and sera from P. leucopus mice were tested for serologic evidence of infection by indirect immunofluorescence. PCR analyses revealed the presence of HGE agent DNA in 20 of the 190 samples (10.5%) tested. Of the 119 P. leucopus mouse serum samples that were analyzed, 12 (10.1%) contained Ehrlichia equi antibodies. In 3 of 119 (2.5%) P. leucopus mice from which both blood and serum were collected. HGE agent DNA and antibodies against E. equi were present. Animals with evidence of infection with the HGE agent are widely distributed around the Minneapolis-St. Paul area in regions with known I. scapularis tick activity. Small mammals that are frequent hosts for larval I. scapularis ticks and that are found in areas where HGE occurs are likely to be a major reservoir from which infected ticks that bite humans are derived. PMID:9157141

  20. Interference between the agents of Lyme disease and human granulocytic ehrlichiosis in a natural reservoir host.

    PubMed

    Levin, M L; Fish, D

    2001-01-01

    Agents of Lyme disease (Borrelia burgdorferi) and human granulocytic ehrlichiosis (Ehrlichia phagocytophila) are perpetuated in a natural cycle involving the black-legged tick (Ixodes scapularis) and its vertebrate hosts. Using I. scapularis nymphs as the mode of infectious challenge, we studied how infection with one pathogen in white-footed mice (Peromyscus leucopus) affects their ability to acquire the other agent and subsequently to infect larvae, which these agents would do in nature. Two groups of mice were infected with either B. burgdorferi or E. phagocytophila. One week later, B. burgdorferi-infected mice were challenged with E. phagocytophila, and E. phagocytophila-infected mice were challenged with B. burgdorferi. Simultaneously, two control groups of uninfected mice were infected with each agent from the same tick cohorts used on the first groups of mice. Uninfected I. scapularis larvae were fed on all mice for xenodiagnosis at weekly intervals lasting 2 months. For the B. burgdorferi challenge, all control and E. phagocytophila-infected mice acquired B. burgdorferi. However, fewer xenodiagnostic larvae acquired B. burgdorferi from mice with mixed infections compared with mice infected with B. burgdorferi only. For the E. phagocytophila challenge, all five control mice acquired E. phagocytophila, but only two of five mice infected with B. burgdorferi subsequently acquired E. phagocytophila. Consequently, mice with both infections produced fewer xenodiagnostic ticks infected with E. phagocytophila than mice infected with E. phagocytophila only. Thus, a primary infection with either B. burgdorferi or E. phagocytophila in mice inhibited transmission of a second agent, suggesting interference between these two agents.

  1. Discovery and development of natural product oridonin-inspired anticancer agents.

    PubMed

    Ding, Ye; Ding, Chunyong; Ye, Na; Liu, Zhiqing; Wold, Eric A; Chen, Haiying; Wild, Christopher; Shen, Qiang; Zhou, Jia

    2016-10-21

    Natural products have historically been, and continue to be, an invaluable source for the discovery of various therapeutic agents. Oridonin, a natural diterpenoid widely applied in traditional Chinese medicines, exhibits a broad range of biological effects including anticancer and anti-inflammatory activities. To further improve its potency, aqueous solubility and bioavailability, the oridonin template serves as an exciting platform for drug discovery to yield better candidates with unique targets and enhanced drug properties. A number of oridonin derivatives (e.g. HAO472) have been designed and synthesized, and have contributed to substantial progress in the identification of new agents and relevant molecular mechanistic studies toward the treatment of human cancers and other diseases. This review summarizes the recent advances in medicinal chemistry on the explorations of novel oridonin analogues as potential anticancer therapeutics, and provides a detailed discussion of future directions for the development and progression of this class of molecules into the clinic. PMID:27344488

  2. Honey as a Potential Natural Anticancer Agent: A Review of Its Mechanisms

    PubMed Central

    Ahmed, Sarfraz

    2013-01-01

    The main treatment for cancer is by using chemotherapy and radiotherapy which themselves are toxic to other viable cells of the body. Recently, there are many studies focusing on the use of natural products for cancer prevention and treatment. Of these natural products, honey has been extensively researched. The mechanism of the anti-cancer activity of honey as chemopreventive and therapeutic agent has not been completely understood. The possible mechanisms are due to its apoptotic, antiproliferative, antitumor necrosis factor (anti-TNF), antioxidant, anti-inflammatory, estrogenic and immunomodulatory activities. We collate the findings of several studies published in the literature in order to understand the mechanism of its action. PMID:24363771

  3. Comparative analysis of using natural and radiogenic lead as heat-transfer agent in fast reactors

    NASA Astrophysics Data System (ADS)

    Laas, R. A.; Gizbrekht, R. V.; Komarov, P. A.; Nesterov, V. N.

    2016-06-01

    Fast reactors with lead coolant have several advantages over analogues. Performance can be further improved by replacement of natural composition lead with radiogenic one. Thus, two main issues need to be addressed: induced radioactivity in coolant and efficient neutron multiplication factor in the core will be changed and need to be estimated. To address these issues analysis of the scheme of the nuclear transformations in the lead heat-transfer agent in the process of radiation was carried out. Induced radioactivity of radiogenic and natural lead has been studied. It is shown that replacement of lead affects multiplication factor in a certain way. Application of radiogenic lead can significantly affect reactor operation.

  4. Learning Natural Selection in 4th Grade with Multi-Agent-Based Computational Models

    NASA Astrophysics Data System (ADS)

    Dickes, Amanda Catherine; Sengupta, Pratim

    2013-06-01

    In this paper, we investigate how elementary school students develop multi-level explanations of population dynamics in a simple predator-prey ecosystem, through scaffolded interactions with a multi-agent-based computational model (MABM). The term "agent" in an MABM indicates individual computational objects or actors (e.g., cars), and these agents obey simple rules assigned or manipulated by the user (e.g., speeding up, slowing down, etc.). It is the interactions between these agents, based on the rules assigned by the user, that give rise to emergent, aggregate-level behavior (e.g., formation and movement of the traffic jam). Natural selection is such an emergent phenomenon, which has been shown to be challenging for novices (K16 students) to understand. Whereas prior research on learning evolutionary phenomena with MABMs has typically focused on high school students and beyond, we investigate how elementary students (4th graders) develop multi-level explanations of some introductory aspects of natural selection—species differentiation and population change—through scaffolded interactions with an MABM that simulates predator-prey dynamics in a simple birds-butterflies ecosystem. We conducted a semi-clinical interview based study with ten participants, in which we focused on the following: a) identifying the nature of learners' initial interpretations of salient events or elements of the represented phenomena, b) identifying the roles these interpretations play in the development of their multi-level explanations, and c) how attending to different levels of the relevant phenomena can make explicit different mechanisms to the learners. In addition, our analysis also shows that although there were differences between high- and low-performing students (in terms of being able to explain population-level behaviors) in the pre-test, these differences disappeared in the post-test.

  5. The effect of two remineralizing agents and natural saliva on bleached enamel hardness

    PubMed Central

    Heshmat, Haleh; Ganjkar, Maryam Hoorizad; Miri, Yasaman; Fard, Mohamad Javad Kharrazi

    2016-01-01

    Background: In order to compensate the adverse consequences of bleaching agents, the use of fluoride-containing remineralizing agents has been suggested by many researchers. The aim of this study was to compare the effect of applying two remineralizing materials on bleached enamel hardness and in comparison to natural saliva. Materials and Methods: In this experimental study, 30 enamel samples of sound human permanent molars were prepared for this study. Microhardness (MH) of all specimens was measured and 35% hydrogen peroxide was applied 3 times to the specimens. After completion of the bleaching process, MH of samples was measured and then enamel specimens were divided into three groups each of 10, specimens of groups 1 and 2 were subjected to daily application of hydroxyl apatite (Remin Pro) and casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACPF) (MI Paste Plus) pastes, respectively, for 15 days. In group 3, the specimens were stored in the operators' natural saliva at room temperature in this period of time. Final MH of all groups was measured. The data were analyzed using repeated measures ANOVA (α = 0.05). Results: The hardness significantly decreased in all groups following bleaching. Application of either Remin Pro, CPP-ACPF or natural saliva increased the hardness significantly. The hardness of the three test groups after 15 days were statistically similar to each other. Conclusion: The hardness of enamel increases eventually after exposure to either MI Paste Plus, Remin Pro or natural saliva. PMID:26962316

  6. A Review of Natural Stimulant and Non‐stimulant Thermogenic Agents

    PubMed Central

    Badmaev, Vladimir

    2016-01-01

    Obesity and overweight are major health issues. Exercise and calorie intake control are recognized as the primary mechanisms for addressing excess body weight. Naturally occurring thermogenic plant constituents offer adjunct means for assisting in weight management. The controlling mechanisms for thermogenesis offer many intervention points. Thermogenic agents can act through stimulation of the central nervous system with associated adverse cardiovascular effects and through metabolic mechanisms that are non‐stimulatory or a combination thereof. Examples of stimulatory thermogenic agents that will be discussed include ephedrine and caffeine. Examples of non‐stimulatory thermogenic agents include p‐synephrine (bitter orange extract), capsaicin, forskolin (Coleus root extract), and chlorogenic acid (green coffee bean extract). Green tea is an example of a thermogenic with the potential to produce mild but clinically insignificant undesirable stimulatory effects. The use of the aforementioned thermogenic agents in combination with other extracts such as those derived from Salacia reticulata, Sesamum indicum, Lagerstroemia speciosa, Cissus quadrangularis, and Moringa olifera, as well as the use of the carotenoids as lutein and fucoxanthin, and flavonoids as naringin and hesperidin can further facilitate energy metabolism and weight management as well as sports performance without adverse side effects. © 2016 The Authors Phytotherapy Research published by John Wiley & Sons Ltd. PMID:26856274

  7. A Review of Natural Stimulant and Non-stimulant Thermogenic Agents.

    PubMed

    Stohs, Sidney J; Badmaev, Vladimir

    2016-05-01

    Obesity and overweight are major health issues. Exercise and calorie intake control are recognized as the primary mechanisms for addressing excess body weight. Naturally occurring thermogenic plant constituents offer adjunct means for assisting in weight management. The controlling mechanisms for thermogenesis offer many intervention points. Thermogenic agents can act through stimulation of the central nervous system with associated adverse cardiovascular effects and through metabolic mechanisms that are non-stimulatory or a combination thereof. Examples of stimulatory thermogenic agents that will be discussed include ephedrine and caffeine. Examples of non-stimulatory thermogenic agents include p-synephrine (bitter orange extract), capsaicin, forskolin (Coleus root extract), and chlorogenic acid (green coffee bean extract). Green tea is an example of a thermogenic with the potential to produce mild but clinically insignificant undesirable stimulatory effects. The use of the aforementioned thermogenic agents in combination with other extracts such as those derived from Salacia reticulata, Sesamum indicum, Lagerstroemia speciosa, Cissus quadrangularis, and Moringa olifera, as well as the use of the carotenoids as lutein and fucoxanthin, and flavonoids as naringin and hesperidin can further facilitate energy metabolism and weight management as well as sports performance without adverse side effects. © 2016 The Authors Phytotherapy Research published by John Wiley & Sons Ltd. PMID:26856274

  8. A Review of Natural Stimulant and Non-stimulant Thermogenic Agents.

    PubMed

    Stohs, Sidney J; Badmaev, Vladimir

    2016-05-01

    Obesity and overweight are major health issues. Exercise and calorie intake control are recognized as the primary mechanisms for addressing excess body weight. Naturally occurring thermogenic plant constituents offer adjunct means for assisting in weight management. The controlling mechanisms for thermogenesis offer many intervention points. Thermogenic agents can act through stimulation of the central nervous system with associated adverse cardiovascular effects and through metabolic mechanisms that are non-stimulatory or a combination thereof. Examples of stimulatory thermogenic agents that will be discussed include ephedrine and caffeine. Examples of non-stimulatory thermogenic agents include p-synephrine (bitter orange extract), capsaicin, forskolin (Coleus root extract), and chlorogenic acid (green coffee bean extract). Green tea is an example of a thermogenic with the potential to produce mild but clinically insignificant undesirable stimulatory effects. The use of the aforementioned thermogenic agents in combination with other extracts such as those derived from Salacia reticulata, Sesamum indicum, Lagerstroemia speciosa, Cissus quadrangularis, and Moringa olifera, as well as the use of the carotenoids as lutein and fucoxanthin, and flavonoids as naringin and hesperidin can further facilitate energy metabolism and weight management as well as sports performance without adverse side effects. © 2016 The Authors Phytotherapy Research published by John Wiley & Sons Ltd.

  9. Naturally derived anti-hepatitis B virus agents and their mechanism of action

    PubMed Central

    Wu, Yi-Hang

    2016-01-01

    Despite that some approved drugs and genetically engineered vaccines against hepatitis B virus (HBV) are available for HBV patients, HBV infection is still a severe public health problem in the world. All the approved therapeutic drugs (including interferon-alpha and nucleoside analogues) have their limitations. No drugs or therapeutic methods can cure hepatitis B so far. Therefore, it is urgently needed to discover and develop new anti-HBV drugs, especially non-nucleoside agents. Naturally originated compounds with enormous molecular complexity and diversity offer a great opportunity to find novel anti-HBV lead compounds with specific antiviral mechanisms. In this review, the natural products against HBV are discussed according to their chemical classes such as terpenes, lignans, phenolic acids, polyphenols, lactones, alkaloids and flavonoids. Furthermore, novel mode of action or new targets of some representative anti-HBV natural products are also discussed. The aim of this review is to report new discoveries and updates pertaining to anti-HBV natural products in the last 20 years, especially novel skeletons and mode of action. Although many natural products with various skeletons have been reported to exhibit potent anti-HBV effects to date, scarcely any of them are found in the list of conventional anti-HBV drugs worldwide. Additionly, in anti-HBV mechanism of action, only a few references reported new targets or novel mode of action of anti-HBV natural products. PMID:26755870

  10. Natural fatty acid synthase inhibitors as potent therapeutic agents for cancers: A review.

    PubMed

    Zhang, Jia-Sui; Lei, Jie-Ping; Wei, Guo-Qing; Chen, Hui; Ma, Chao-Ying; Jiang, He-Zhong

    2016-09-01

    Context Fatty acid synthase (FAS) is the only mammalian enzyme to catalyse the synthesis of fatty acid. The expression level of FAS is related to cancer progression, aggressiveness and metastasis. In recent years, research on natural FAS inhibitors with significant bioactivities and low side effects has increasingly become a new trend. Herein, we present recent research progress on natural fatty acid synthase inhibitors as potent therapeutic agents. Objective This paper is a mini overview of the typical natural FAS inhibitors and their possible mechanism of action in the past 10 years (2004-2014). Method The information was collected and compiled through major databases including Web of Science, PubMed, and CNKI. Results Many natural products induce cancer cells apoptosis by inhibiting FAS expression, with fewer side effects than synthetic inhibitors. Conclusion Natural FAS inhibitors are widely distributed in plants (especially in herbs and foods). Some natural products (mainly phenolics) possessing potent biological activities and stable structures are available as lead compounds to synthesise promising FAS inhibitors.

  11. Phylogenetic Analysis of Entomoparasitic Nematodes, Potential Control Agents of Flea Populations in Natural Foci of Plague

    PubMed Central

    Koshel, E. I.; Aleshin, V. V.; Eroshenko, G. A.; Kutyrev, V. V.

    2014-01-01

    Entomoparasitic nematodes are natural control agents for many insect pests, including fleas that transmit Yersinia pestis, a causative agent of plague, in the natural foci of this extremely dangerous zoonosis. We examined the flea samples from the Volga-Ural natural focus of plague for their infestation with nematodes. Among the six flea species feeding on different rodent hosts (Citellus pygmaeus, Microtus socialis, and Allactaga major), the rate of infestation varied from 0 to 21%. The propagation rate of parasitic nematodes in the haemocoel of infected fleas was very high; in some cases, we observed up to 1,000 juveniles per flea specimen. Our study of morphology, life cycle, and rDNA sequences of these parasites revealed that they belong to three distinct species differing in the host specificity. On SSU and LSU rRNA phylogenies, these species representing three genera (Rubzovinema, Psyllotylenchus, and Spilotylenchus), constitute a monophyletic group close to Allantonema and Parasitylenchus, the type genera of the families Allantonematidae and Parasitylenchidae (Nematoda: Tylenchida). We discuss the SSU-ITS1-5.8S-LSU rDNA phylogeny of the Tylenchida with a special emphasis on the suborder Hexatylina. PMID:24804197

  12. Synthesis and Evaluation of a Novel Deguelin Derivative, L80, which Disrupts ATP Binding to the C-terminal Domain of Heat Shock Protein 90.

    PubMed

    Lee, Su-Chan; Min, Hye-Young; Choi, Hoon; Kim, Ho Shin; Kim, Kyong-Cheol; Park, So-Jung; Seong, Myeong A; Seo, Ji Hae; Park, Hyun-Ju; Suh, Young-Ger; Kim, Kyu-Won; Hong, Hyun-Seok; Kim, Hee; Lee, Min-Young; Lee, Jeewoo; Lee, Ho-Young

    2015-08-01

    The clinical benefit of current anticancer regimens for lung cancer therapy is still limited due to moderate efficacy, drug resistance, and recurrence. Therefore, the development of effective anticancer drugs for first-line therapy and for optimal second-line treatment is necessary. Because the 90-kDa molecular chaperone heat shock protein (Hsp90) contributes to the maturation of numerous mutated or overexpressed oncogenic proteins, targeting Hsp90 may offer an effective anticancer therapy. Here, we investigated antitumor activities and toxicity of a novel deguelin-derived C-terminal Hsp90 inhibitor, designated L80. L80 displayed significant inhibitory effects on the viability, colony formation, angiogenesis-stimulating activity, migration, and invasion of a panel of non-small cell lung cancer cell lines and their sublines with acquired resistance to paclitaxel with minimal toxicity to normal lung epithelial cells, hippocampal cells, vascular endothelial cells, and ocular cells. Biochemical analyses and molecular docking simulation revealed that L80 disrupted Hsp90 function by binding to the C-terminal ATP-binding pocket of Hsp90, leading to the disruption of the interaction between hypoxia-inducible factor (HIF)-1α and Hsp90, downregulation of HIF-1α and its target genes, including vascular endothelial growth factor (VEGF) and insulin-like growth factor 2 (IGF2), and decreased the expression of various Hsp90 client proteins. Consistent with these in vitro findings, L80 exhibited significant antitumor and antiangiogenic activities in H1299 xenograft tumors. These results suggest that L80 represents a novel C-terminal Hsp90 inhibitor with effective anticancer activities with minimal toxicities.

  13. Xanthones from Mangosteen Extracts as Natural Chemopreventive Agents: Potential Anticancer Drugs

    PubMed Central

    Shan, T.; Ma, Q.; Guo, K.; Liu, J.; Li, W.; Wang, F.; Wu, E.

    2011-01-01

    Despite decades of research, the treatment and management of malignant tumors still remain a formidable challenge for public health. New strategies for cancer treatment are being developed, and one of the most promising treatment strategies involves the application of chemopreventive agents. The search for novel and effective cancer chemopreventive agents has led to the identification of various naturally occurring compounds. Xanthones, from the pericarp, whole fruit, heartwood, and leaf of mangosteen (Garcinia mangostana Linn., GML), are known to possess a wide spectrum of pharmacologic properties, including anti-oxidant, anti-tumor, anti-allergic, anti-inflammatory, anti-bacterial, anti-fungal, and anti-viral activities. The potential chemopreventive and chemotherapeutic activities of xanthones have been demonstrated in different stages of carcinogenesis (initiation, promotion, and progression) and are known to control cell division and growth, apoptosis, inflammation, and metastasis. Multiple lines of evidence from numerous in vitro and in vivo studies have confirmed that xanthones inhibit proliferation of a wide range of human tumor cell types by modulating various targets and signaling transduction pathways. Here we provide a concise and comprehensive review of preclinical data and assess the observed anticancer effects of xanthones, supporting its remarkable potential as an anticancer agent. PMID:21902651

  14. A naturally occurring contrast agent for OCT imaging of smokers' lung

    NASA Astrophysics Data System (ADS)

    Yang, Ying; Bagnaninchi, Pierre O.; Whiteman, Suzanne C.; Gey van Pittius, Daniel; El Haj, Alicia J.; Spiteri, Monica A.; Wang, Ruikang K.

    2005-08-01

    Optical coherence tomography (OCT) offers great potential for clinical applications in terms of its cost, safety and real-time imaging capability. Improvement of its resolution for revealing sub-layers or sub-cellular components within a tissue will further widen its application. In this study we report that carbon pigment, which is frequently present in the lungs of smokers, could be used as a contrast agent to improve the OCT imaging of lung tissue. Carbon produced an intense bright OCT image at a relatively deep location. The parallel histopathological section analysis confirmed the presence of carbon pigment in such tissues. The underlying mechanism of the OCT image formation has been discussed based on a model system in which carbon particles were dispersed in agar gel. Calculations and in-depth intensity profiles of OCT revealed that higher refractive index particles with a size close to or smaller than the wavelength would greatly increase backscattering and generate a sharp contrast, while a particle size several times larger than the wavelength would absorb or obstruct the light path. The naturally occurring contrast agent could provide a diagnostic biomarker of lung tissue in smokers. Furthermore, carbon under such circumstances, can be used as an effective exogenous contrast agent, with which specific components or tissues exhibiting early tumour formation can be optically labelled to delineate the location and boundary, providing potential for early cancer detection and its treatment.

  15. Assay Development for the Discovery of Semaphorin 3B Inducing Agents from Natural Product Sources

    PubMed Central

    Yong, Yeonjoong; Pan, Li; Ren, Yulin; Fatima, Nighat; Ahmed, Safia; Chang, Leng Chee; Zhang, Xiaoli; Kinghorn, A. Douglas; Swanson, Steven M.; Carcache de Blanco, Esperanza J.

    2014-01-01

    Semaphorins are a class of membrane-bound and secreted proteins. They have been found to regulate basic cell functions such as axonal growth cone guidance and recent studies have focused on their effect on tumor progression. Semaphorin 3B (Sema 3B) particularly is a secreted protein that has been known to modulate proliferation and apoptosis, processes that are critical for tumor progression and development. In spite of its importance, there is yet no high-throughput screening assay available to detect or quantify the expression of Sema 3B for natural product anticancer drug discovery purposes. Therefore, the development of a new high-throughput bioassay for the discovery of Sema 3B inducing agents from natural product sources is described herein. A wide variety of pure compounds and extracts from plants and microorganisms has been found suitable for screening using this Sema 3B assay to detect and quantify the effect of Sema 3B inducing agents and thereby identify new selective bioactive Sema 3B lead compounds for anticancer drug discovery and development. Also, this new bioassay procedure is based on a high-throughput platform using an enzyme-linked immunosorbent assay that involves the optimization of sensitivity and selectivity levels as well as accuracy, reproducibility, robustness, and cost effectiveness. PMID:25016954

  16. Regulation of MicroRNAs by Natural Agents: New Strategies in Cancer Therapies

    PubMed Central

    2014-01-01

    MicroRNAs (miRNAs) are short noncoding RNA which regulate gene expression by messenger RNA (mRNA) degradation or translation repression. The plethora of published reports in recent years demonstrated that they play fundamental roles in many biological processes, such as carcinogenesis, angiogenesis, programmed cell death, cell proliferation, invasion, migration, and differentiation by acting as tumour suppressor or oncogene, and aberrations in their expressions have been linked to onset and progression of various cancers. Furthermore, each miRNA is capable of regulating the expression of many genes, allowing them to simultaneously regulate multiple cellular signalling pathways. Hence, miRNAs have the potential to be used as biomarkers for cancer diagnosis and prognosis as well as therapeutic targets. Recent studies have shown that natural agents such as curcumin, resveratrol, genistein, epigallocatechin-3-gallate, indole-3-carbinol, and 3,3′-diindolylmethane exert their antiproliferative and/or proapoptotic effects through the regulation of one or more miRNAs. Therefore, this review will look at the regulation of miRNAs by natural agents as a means to potentially enhance the efficacy of conventional chemotherapy through combinatorial therapies. It is hoped that this would provide new strategies in cancer therapies to improve overall response and survival outcome in cancer patients. PMID:25254214

  17. Natural products for cancer-targeted therapy: citrus flavonoids as potent chemopreventive agents.

    PubMed

    Meiyanto, Edy; Hermawan, Adam; Anindyajati

    2012-01-01

    Targeted therapy has been a very promising strategy of drug development research. Many molecular mechanims of diseases have been known to be regulated by abundance of proteins, such as receptors and hormones. Chemoprevention for treatment and prevention of diseases are continuously developed. Pre-clinical and clinical studies in chemoprevention field yielded many valuable data in preventing the onset of disease and suppressing the progress of their growth, making chemoprevention a challenging and a very rational strategy in future researches. Natural products being rich of flavonoids are those fruits belong to the genus citrus. Ethanolic extract of Citrus reticulata and Citrus aurantiifolia peels showed anticarcinogenic, antiproliferative, co-chemotherapeutic and estrogenic effects. Several examples of citrus flavonoids that are potential as chemotherapeutic agents are tangeretin, nobiletin, hesperetin, hesperidin, naringenin, and naringin. Those flavonoids have been shown to possess inhibition activity on certain cancer cells' growth through various mechanisms. Moreover, citrus flavonoids also perform promising effect in combination with several chemotherapeutic agents against the growth of cancer cells. Some mechanisms involved in those activities are through cell cycle modulation, antiangiogenic effect, and apoptosis induction. Previous studies showed that tangeretin suppressed the growth of T47D breast cancer cells by inhibiting ERK phosphorylation. While in combination with tamoxifen, doxorubicin, and 5-FU, respectively, it was proven to be synergist on several cancer cells. Hesperidin and naringenin increased cytotoxicitity of doxorubicin on MCF-7 cells and HeLa cells. Besides, citrus flavonoids also performed estrogenic effect in vivo. One example is hesperidin having the ability to decrease the concentration of serum and hepatic lipid and reduce osteoporosis of ovariectomized rats. Those studies showed the great potential of citrus fruits as natural product

  18. HIV Latency-Reversing Agents Have Diverse Effects on Natural Killer Cell Function

    PubMed Central

    Garrido, Carolina; Spivak, Adam M.; Soriano-Sarabia, Natalia; Checkley, Mary Ann; Barker, Edward; Karn, Jonathan; Planelles, Vicente; Margolis, David M.

    2016-01-01

    In an effort to clear persistent HIV infection and achieve a durable therapy-free remission of HIV disease, extensive pre-clinical studies and early pilot clinical trials are underway to develop and test agents that can reverse latent HIV infection and present viral antigen to the immune system for clearance. It is, therefore, critical to understand the impact of latency-reversing agents (LRAs) on the function of immune effectors needed to clear infected cells. We assessed the impact of LRAs on the function of natural killer (NK) cells, the main effector cells of the innate immune system. We studied the effects of three histone deacetylase inhibitors [SAHA or vorinostat (VOR), romidepsin, and panobinostat (PNB)] and two protein kinase C agonists [prostratin (PROST) and ingenol] on the antiviral activity, cytotoxicity, cytokine secretion, phenotype, and viability of primary NK cells. We found that ex vivo exposure to VOR had minimal impact on all parameters assessed, while PNB caused a decrease in NK cell viability, antiviral activity, and cytotoxicity. PROST caused non-specific NK cell activation and, interestingly, improved antiviral activity. Overall, we found that LRAs can alter the function and fate of NK cells, and these effects must be carefully considered as strategies are developed to clear persistent HIV infection. PMID:27708642

  19. A Naturally Occurring Antibody Fragment Neutralizes Infectivity of Diverse Infectious Agents

    PubMed Central

    Polonelli, Luciano; Ciociola, Tecla; Elviri, Lisa; Zanello, Pier Paolo; Giovati, Laura; Arruda, Denise C.; Muñoz, Julián E.; Mortara, Renato A.; Morace, Giulia; Borghi, Elisa; Galati, Serena; Marin, Oriano; Casoli, Claudio; Pilotti, Elisabetta; Ronzi, Paola; Travassos, Luiz R.; Magliani, Walter; Conti, Stefania

    2016-01-01

    A phosphorylated peptide, named K40H, derived from the constant region of IgMs was detected in human serum by liquid chromatography coupled to high-resolution mass spectrometry. Synthetic K40H proved to exert a potent in vitro activity against fungal pathogens, and to inhibit HIV-1 replication in vitro and ex vivo. It also showed a therapeutic effect against an experimental infection by Candida albicans in the invertebrate model Galleria mellonella. K40H represents the proof of concept of the innate role that naturally occurring antibody fragments may exert against infectious agents, shedding a new light upon the posthumous role of antibodies and opening a new scenario on the multifaceted functionality of humoral immunity. PMID:27725769

  20. Natural and genetically engineered viral agents for oncolysis and gene therapy of human cancers.

    PubMed

    Sinkovics, Joseph G; Horvath, Joseph C

    2008-12-01

    combination of naturally oncolytic viruses and wild-type viruses rendered oncolytic and harmless by genetic engineering, that will induce complete remissions of human tumors. It may be necessary to co-administer certain chemotherapeutic agents, advanced cancer vaccines, or even immune lymphocytes, and targeted therapeuticals, to ascertain, that remissions induced by the viral agents will remain complete and durable; will co-operate with anti-tumor host immune reactions, and eventually will result in cures of advanced metastatic human cancers. PMID:19104757

  1. Natural and genetically engineered viral agents for oncolysis and gene therapy of human cancers.

    PubMed

    Sinkovics, Joseph G; Horvath, Joseph C

    2008-12-01

    combination of naturally oncolytic viruses and wild-type viruses rendered oncolytic and harmless by genetic engineering, that will induce complete remissions of human tumors. It may be necessary to co-administer certain chemotherapeutic agents, advanced cancer vaccines, or even immune lymphocytes, and targeted therapeuticals, to ascertain, that remissions induced by the viral agents will remain complete and durable; will co-operate with anti-tumor host immune reactions, and eventually will result in cures of advanced metastatic human cancers.

  2. Nitrate-induced photolysis in natural waters: Controls on concentrations of hydroxyl radical photo-intermediates by natural scavenging agents

    SciTech Connect

    Brezonik, P.L.; Fulkerson-Brekken, J.

    1998-10-01

    The importance of the principal natural scavenging agents for hydroxyl radicals ({sup {sm_bullet}}OH) was evaluated, and a general framework was developed to predict the significance of nitrate-induced, {sup {sm_bullet}}OH-mediated degradation of aquatic contaminants. Rate constants for *OH scavenging by dissolved organic matter (DOM) from five surface water sources were in a narrow range which is similar to previously reported values and suggests that the importance of DOM as a {sup {sm_bullet}}OH sink can be estimated simply from the dissolved organic carbon (DOC) concentration of a water. Scavenging of {sup {sm_bullet}}*OH by carbonate and bicarbonate is generally less important, but these ions can be the major cause of *OH scavenging in low DOC, high alkalinity waters. Use of the framework is illustrated by predicting levels of {sup {sm_bullet}}OH and half-lives of the corn herbicide acetochlor in waters ranging from pristine to highly influenced by agricultural activities.

  3. Nature Concocts & Expels’: The Agents and Processes of Recovery from Disease in Early Modern England

    PubMed Central

    Newton, Hannah

    2015-01-01

    The ‘golden saying’ in early modern medicine was ‘Nature is the healer of disease’. This article uncovers the meaning and significance of this forgotten axiom by investigating perceptions of the agents and physiological processes of recovery from illness in England, c.1580–1720. Drawing on sources such as medical texts and diaries, it shows that doctors and laypeople attributed recovery to three agents—God, Nature and the practitioner. While scholars are familiar with the roles of providence and medicine, the vital agency of Nature has been overlooked. In theory, the agents operated in a hierarchy: Nature was ‘God's instrument’, and the physician, ‘Nature's servant’; but in practice the power balance was more ambivalent. Nature was depicted both as a housewife who cooked and cleaned the humours, and as a warrior who defeated the disease. Through exploring these complex dynamics, the article sheds fresh light on concepts of gender, disease and bodies. PMID:26217069

  4. A Quantitative Ethnopharmacological Documentation of Natural Pharmacological Agents Used by Pediatric Patients in Mauritius

    PubMed Central

    Mahomoodally, M. Fawzi; Sreekeesoon, D. Priyamka

    2014-01-01

    The pediatric population constitutes the most vulnerable patients due to a dearth of approved drugs. Consequently, there is a pressing need to probe novel natural pharmacological agents in an endeavour to develop new drugs to address pediatric illnesses. To date, no studies have explored the use of natural therapies for pediatric health care in Mauritius. Parents (n = 325) from different regions of the island were interviewed. Quantitative indexes such as fidelity level (FL), informant consensus factor (FIC), and use-value (UV) were calculated. Thirty-two plants were reported to be used by pediatric patients. Gastrointestinal disorders (FIC = 0.97) encompassing regurgitation, infantile colic, and stomach aches were the most common ailments managed with herbs. Matricaria chamomilla used for infantile colic and its pharmacological properties has previously been documented for pediatric patients. Product from A. mellifera (UV = 0.75) was the most utilized zootherapy for managing cough. Most plants and animal products reported in this study have bioactive constituents supported by existing scientific literature but their use for the pediatric population is scant. The present ethnopharmacological study has opened new perspectives for further research into their pharmacology, which can subsequently support and facilitate timely pediatric medicinal product development. PMID:24949418

  5. A quantitative ethnopharmacological documentation of natural pharmacological agents used by pediatric patients in Mauritius.

    PubMed

    Mahomoodally, M Fawzi; Sreekeesoon, D Priyamka

    2014-01-01

    The pediatric population constitutes the most vulnerable patients due to a dearth of approved drugs. Consequently, there is a pressing need to probe novel natural pharmacological agents in an endeavour to develop new drugs to address pediatric illnesses. To date, no studies have explored the use of natural therapies for pediatric health care in Mauritius. Parents (n = 325) from different regions of the island were interviewed. Quantitative indexes such as fidelity level (FL), informant consensus factor (F IC), and use-value (UV) were calculated. Thirty-two plants were reported to be used by pediatric patients. Gastrointestinal disorders (F IC = 0.97) encompassing regurgitation, infantile colic, and stomach aches were the most common ailments managed with herbs. Matricaria chamomilla used for infantile colic and its pharmacological properties has previously been documented for pediatric patients. Product from A. mellifera (UV = 0.75) was the most utilized zootherapy for managing cough. Most plants and animal products reported in this study have bioactive constituents supported by existing scientific literature but their use for the pediatric population is scant. The present ethnopharmacological study has opened new perspectives for further research into their pharmacology, which can subsequently support and facilitate timely pediatric medicinal product development. PMID:24949418

  6. Saffron as an antidote or a protective agent against natural or chemical toxicities.

    PubMed

    Razavi, Bibi Marjan; Hosseinzadeh, Hossein

    2015-01-01

    Saffron (Crocus sativus) is an extensively used food additive for its color and taste. Since ancient times this plant has been introduced as a marvelous medicine throughout the world. The wide spectrum of saffron pharmacological activities is related to its major constituents including crocin, crocetin and safranal. Based on several studies, saffron and its active ingredients have been used as an antioxidant, antiinflammatory and antinociceptive, antidepressant, antitussive, anticonvulsant, memory enhancer, hypotensive and anticancer. According to the literatures, saffron has remarkable therapeutic effects. The protective effects of saffron and its main constituents in different tissues including brain, heart, liver, kidney and lung have been reported against some toxic materials either natural or chemical toxins in animal studies.In this review article, we have summarized different in vitro and animal studies in scientific databases which investigate the antidotal and protective effects of saffron and its major components against natural toxins and chemical-induced toxicities. Due to the lake of human studies, further investigations are required to ascertain the efficacy of saffron as an antidote or a protective agent in human intoxication.

  7. 'Genipin' - the natural water soluble cross-linking agent and its importance in the modified drug delivery systems: an overview.

    PubMed

    Manickam, Balamurugan; Sreedharan, Rajesh; Elumalai, Manogaran

    2014-01-01

    One of the popular approaches in controlling drug delivery from the polymeric carriers is suitably achieved by the inclusion of crosslinking agents into the formulations at different concentrations. Nevertheless, addition of the chemical crosslinkers such as glutaraldehyde, formaldehyde etc, used in the drug delivery systems causes very serious cytotoxic reactions. These chemical crosslinking agents did not offer any significant advantageous effects when compared to the natural crosslinking agents for instance genipin, which is quite less toxic, biocompatible and offers very stable crosslinked products. Based on the earlier reports the safety of this particular natural crosslinker is very well established, since it has been widely used as a Chinese traditional medicine for long-time, isolated from fruits of the plant Gardenia jasminoides Ellis. This concise article largely portrayed the value of this unique natural crosslinker, utilized in controlling the drug delivery from the various formulations. PMID:24041312

  8. Ginkgo biloba: a natural reducing agent for the synthesis of cytocompatible graphene

    PubMed Central

    Gurunathan, Sangiliyandi; Han, Jae Woong; Park, Jung Hyun; Eppakayala, Vasuki; Kim, Jin-Hoi

    2014-01-01

    Background Graphene is a novel two-dimensional planar nanocomposite material consisting of rings of carbon atoms with a hexagonal lattice structure. Graphene exhibits unique physical, chemical, mechanical, electrical, elasticity, and cytocompatible properties that lead to many potential biomedical applications. Nevertheless, the water-insoluble property of graphene restricts its application in various aspects of biomedical fields. Therefore, the objective of this work was to find a novel biological approach for an efficient method to synthesize water-soluble and cytocompatible graphene using Ginkgo biloba extract (GbE) as a reducing and stabilizing agent. In addition, we investigated the biocompatibility effects of graphene in MDA-MB-231 human breast cancer cells. Materials and methods Synthesized graphene oxide (GO) and GbE-reduced GO (Gb-rGO) were characterized using various sequences of techniques: ultraviolet-visible (UV-vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and Raman spectroscopy. Biocompatibility of GO and Gb-rGO was assessed in human breast cancer cells using a series of assays, including cell viability, apoptosis, and alkaline phosphatase (ALP) activity. Results The successful synthesis of graphene was confirmed by UV-vis spectroscopy and FTIR. DLS analysis was performed to determine the average size of GO and Gb-rGO. X-ray diffraction studies confirmed the crystalline nature of graphene. SEM was used to investigate the surface morphologies of GO and Gb-rGO. AFM was employed to investigate the morphologies of prepared graphene and the height profile of GO and Gb-rGO. The formation of defects in Gb-rGO was confirmed by Raman spectroscopy. The biocompatibility of the prepared GO and Gb-rGO was investigated using a water-soluble tetrazolium 8 assay on human breast cancer cells. GO exhibited a dose-dependent toxicity, whereas Gb

  9. Nature's agents or agents of empire? Entomological workers and environmental change during the construction of the Panama Canal.

    PubMed

    Sutter, Paul S

    2007-12-01

    This essay examines the role that entomological workers played in U.S. public health efforts during the construction of the Panama Canal (1904-1914). Entomological workers were critical to mosquito control efforts aimed at the reduction of tropical fevers such as malaria. But in the process of studying vector mosquitoes, they discovered that many of the conditions that produced mosquitoes were not intrinsic to tropical nature per se but resulted from the human-caused environmental disturbances that accompanied canal building. This realization did not mesh well with an American ideology of tropical triumphalism premised on the notion that the Americans had conquered unalloyed tropical nature in Panama. The result, however, was not a coherent counternarrative but a set of intra-administrative tensions over what controlling nature meant in Panama. Ultimately, entomological workers were loyal not just to the U.S. imperial mission in Panama but also to a modernist culture of science and to the workings of mosquito ecology as they understood them. PMID:18314643

  10. Withaferin-A--A Natural Anticancer Agent with Pleitropic Mechanisms of Action.

    PubMed

    Lee, In-Chul; Choi, Bu Young

    2016-01-01

    Cancer, being the second leading cause of mortality, exists as a formidable health challenge. In spite of our enormous efforts, the emerging complexities in the molecular nature of disease progression limit the real success in finding an effective cancer cure. It is now conceivable that cancer is, in fact, a progressive illness, and the morbidity and mortality from cancer can be reduced by interfering with various oncogenic signaling pathways. A wide variety of structurally diverse classes of bioactive phytochemicals have been shown to exert anticancer effects in a large number of preclinical studies. Multiple lines of evidence suggest that withaferin-A can prevent the development of cancers of various histotypes. Accumulating data from different rodent models and cell culture experiments have revealed that withaferin-A suppresses experimentally induced carcinogenesis, largely by virtue of its potent anti-oxidative, anti-inflammatory, anti-proliferative and apoptosis-inducing properties. Moreover, withaferin-A sensitizes resistant cancer cells to existing chemotherapeutic agents. The purpose of this review is to highlight the mechanistic aspects underlying anticancer effects of withaferin-A. PMID:26959007

  11. α-Mangostin, a Natural Agent, Enhances the Response of NRAS Mutant Melanoma to Retinoic Acid

    PubMed Central

    Xia, Yun; Chen, Jing; Gong, Chongwen; Chen, Hongxiang; Sun, Jiaming

    2016-01-01

    Background The identification and use of novel compounds alone or in combination hold promise for the fight against NRAS mutant melanoma. Material/Methods We screened a kinase-specific inhibitor library through combining it with α-Mangostin in NRAS mutant melanoma cell line, and verified the enhancing effect of α-Mangostin through inhibition of the tumorigenesis pathway. Results Within the kinase inhibitors, retinoic acid showed a significant synergistic effect with α-Mangostin. α-Mangostin also can reverse the drug resistance of retinoic acid in RARa siRNA-transduced sk-mel-2 cells. Colony assay, TUNEL staining, and the expressions of several apoptosis-related genes revealed that α-Mangostin enhanced the effect of retinoic acid-induced apoptosis. The combination treatment resulted in marked induction of ROS generation and inhibition of the AKT/S6 pathway. Conclusions These results indicate that the combination of these novel natural agents with retinoid acid may be clinically effective in NRAS mutant melanoma. PMID:27104669

  12. Withaferin-A—A Natural Anticancer Agent with Pleitropic Mechanisms of Action

    PubMed Central

    Lee, In-Chul; Choi, Bu Young

    2016-01-01

    Cancer, being the second leading cause of mortality, exists as a formidable health challenge. In spite of our enormous efforts, the emerging complexities in the molecular nature of disease progression limit the real success in finding an effective cancer cure. It is now conceivable that cancer is, in fact, a progressive illness, and the morbidity and mortality from cancer can be reduced by interfering with various oncogenic signaling pathways. A wide variety of structurally diverse classes of bioactive phytochemicals have been shown to exert anticancer effects in a large number of preclinical studies. Multiple lines of evidence suggest that withaferin-A can prevent the development of cancers of various histotypes. Accumulating data from different rodent models and cell culture experiments have revealed that withaferin-A suppresses experimentally induced carcinogenesis, largely by virtue of its potent anti-oxidative, anti-inflammatory, anti-proliferative and apoptosis-inducing properties. Moreover, withaferin-A sensitizes resistant cancer cells to existing chemotherapeutic agents. The purpose of this review is to highlight the mechanistic aspects underlying anticancer effects of withaferin-A. PMID:26959007

  13. An evaluation of pretreatment agents for the stimulation of secondary biogenic coalbed natural gas

    NASA Astrophysics Data System (ADS)

    Huang, Zaixing

    Coalbed methane is considered to be an underexploited source of clean energy and, with the realization of its biogenic nature, it has attracted increasing interest in recent decades. Most of the published studies on biogenic coal bed natural gas (CBNG) have focused either on biostimulation (the addition of nutrients to stimulate the native microbial populations) or bioaugmentation (the addition of both nutrients and non-native microbial consortia of microorganisms). Although these approaches have shown promise, they are predicated on the assumption that the coal seam is nutrient-limited or that the existing microbial communities are not optimized to convert coal to natural gas. The premise of this research is that the organic matter present within the coal matrix is, for the most part, environmentally inert and not readily available to the microorganisms living within the coal seam. The goal of this research has been to focus on treatments that will increase the solubility, and hence the bioavailability, of coal to the indigenous microbial community. Initially, treatment agents representing acids, bases and oxidants were selected to evaluate the potential for the in situ solubilization and depolymerization of subbituminous coal. The bioavailability of the coal-derived constituents was then evaluated aerobically using biometer assays and anaerobic bioassays. The experiments have shown that the acid (nitric acid) and base (sodium hydroxide) treatments are more efficient than the oxidants (potassium permanganate and catalyzed hydrogen peroxide) with respect to total organic carbon (TOC). The carbon contained in the solubilized/depolymerized product of nitric acid treatments accounted for approximately 14% of the carbon from the Powder River Basin (PRB) coal evaluated in the study; however, the biometer assays revealed that the bioavailability of the solubilized/depolymerized products was not directly correlated to the amount of dissolved organic carbon (TOC). The

  14. Learning Natural Selection in 4th Grade with Multi-Agent-Based Computational Models

    ERIC Educational Resources Information Center

    Dickes, Amanda Catherine; Sengupta, Pratim

    2013-01-01

    In this paper, we investigate how elementary school students develop multi-level explanations of population dynamics in a simple predator-prey ecosystem, through scaffolded interactions with a multi-agent-based computational model (MABM). The term "agent" in an MABM indicates individual computational objects or actors (e.g., cars), and these…

  15. Natural ferrihydrite as an agent for reducing turbidity caused by suspended clays.

    PubMed

    Rhoton, F E; Bigham, J M

    2009-01-01

    Biologically impaired waters are often caused by the turbidity associated with elevated suspended sediment concentrations. Turbidity can be reduced by the addition of positively charged compounds that coagulate negatively charged particles in suspension, causing them to flocculate. This research was conducted to determine the effectiveness of ferrihydrite, a poorly crystalline Fe oxide, as a flocculating agent for suspended clays similar to those found in high-turbidity waters of the Mississippi delta. Clay concentrations of 100 mg L(-1) from a Dubbs silt loam (fine silty, mixed, active, thermic Typic Hapludalfs), a Forestdale silty clay loam (fine, smectitic, thermic Typic Hapludalfs), and a Sharkey clay (very fine, smectitic, thermic Chromic Epiaquerts) were suspended in 0.0005 mol L(-1) CaCl(2) solutions at pH 5, 6, 7, or 8. Natural ferrihydrite with a zero point of charge at pH 5.8 was acquired from a drinking water treatment facility and mixed with the suspension at concentrations of 0, 10, 25, and 50 mg L(-1). After settling periods of 24 and 48 h, percent transmittance was measured at a wavelength of 420 nm using a 3-mL sample collected at a depth of 2 cm. The greatest reductions in turbidity after 24-h equilibration were recorded for the pH 5 suspensions of the Dubbs (31%) and Forestdale (37%) clays at a ferrihydrite concentration of 10 mg L(-1) and for the Sharkey clay at a ferrihydrite concentration of 25 mg L(-1) (relative to the 0 ferrihydrite treatment). Water clarity for all samples further increased after 48 h. These results indicate that the effectiveness of ferrihydrite, as a means of reducing turbidity associated with suspended clays, is greatest at pH values below its zero point of charge. PMID:19643754

  16. [Comparison of the thermostability of natural (sulfoprolamine and sodium usnate) and synthetic (climbazole and piroctone olamine) antidandruff agents].

    PubMed

    Coiffard, C; Coiffard, L; de Roeck-Holtzhauer, Y

    1999-09-01

    We compared thermostability of various natural (sulfoprolamine and sodium usnate) or synthetic (climbazol and piroctone olamine) antidandruff agents in aqueous diluted solution at pH around 7. Thermodegradation of these solutions was studied by an isothermal method in thermostatically controlled ovens, at three temperatures (50, 70 and 90 degrees C). For each molecule, we determined at 20 degrees C t90% (time necessary to obtain a decrease of 10% of the initial concentration, value which shows the stability of the product). The present study shows that piroctone olamine is the most stable antidandruff agent among those studied. PMID:10520510

  17. STUDIES ON THE NATURE OF THE AGENT TRANSMITTING LEUCOSIS OF FOWLS

    PubMed Central

    Furth, J.

    1932-01-01

    The filterable agent transmitting leucosis resists drying, retaining its activity for at least 54 days. The conditions of successful desiccation have not been precisely ascertained. By the addition of glycerin the agent can be preserved for at least 104 days. It is not inactivated by freezing in liquid air. At 37.5°C. it loses its activity within 14 days, but retains some of its activity for at least 14 days when kept at 4°C. PMID:19870007

  18. Synthesis of silver nanoparticles using reducing agents obtained from natural sources (Rumex hymenosepalus extracts)

    PubMed Central

    2013-01-01

    We have synthesized silver nanoparticles from silver nitrate solutions using extracts of Rumex hymenosepalus, a plant widely found in a large region in North America, as reducing agent. This plant is known to be rich in antioxidant molecules which we use as reducing agents. Silver nanoparticles grow in a single-step method, at room temperature, and with no addition of external energy. The nanoparticles have been characterized by ultraviolet-visible spectroscopy and transmission electron microscopy, as a function of the ratio of silver ions to reducing agent molecules. The nanoparticle diameters are in the range of 2 to 40 nm. High-resolution transmission electron microscopy and fast Fourier transform analysis show that two kinds of crystal structures are obtained: face-centered cubic and hexagonal. PMID:23841946

  19. Natural Ferrihydrite as an Agent for Reducing Turbidity Caused by Suspended Clays

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The turbidity of water can be reduced by the addition of positively charged compounds which coagulate negatively charged clay particles in suspension causing them to flocculate. This research was conducted to determine the effectiveness of the Fe oxide mineral ferrihydrite as a flocculating agent fo...

  20. Apoptosis and autophagy induction as mechanism of cancer prevention by naturally occurring dietary agents

    PubMed Central

    Mukhtar, Eiman; Adhami, Vaqar Mustafa; Khan, Naghma; Mukhtar, Hasan

    2013-01-01

    Nontoxic naturally occurring compounds, especially those from dietary sources, are receiving increasing consideration for prevention and treatment of diseases including cancer. There is a growing need for innovative anticancer therapies and therefore search for natural compounds with novel biological activities or antineoplastic potential is currently an important area in drug discovery. Support for this interest also comes from increasing concern over the efficacy and safety of many conventional therapies, especially those that run over a long course of time. Laboratory studies in different in vitro and in vivo systems have shown that many natural compounds possess the capacity to regulate response to oxidative stress and DNA damage, suppress angiogenesis, inhibit cell proliferation and induce autophagy and apoptosis. This review discusses the induction of apoptosis and autophagy as a mechanism of cancer prevention by some of the most studied naturally occurring dietary compounds. PMID:23140293

  1. Lab scale testing of novel natural analog in situ stabilization agents

    SciTech Connect

    Shaw, P.

    1997-12-31

    This report summarizes the laboratory-scale test results on several novel in situ treatment and stabilization agents for buried hazardous and radioactive waste. Paraffin, hematite and phosphate materials were examined when combined with soil and other wastes representative of what might be present at buried waste DOE sites. Hematite was made from the reaction of agricultural iron and lime slurries to form gypsum and iron oxide/hydroxide. Common household paraffin was melted, both with and without a zeolitic additive, waste added and then cooled. Magnesium phosphate was made from the reaction of magnesium oxide and phosphoric acid or potassium biphosphate to form, magnesium phosphate. All were tested with soil and some with additional waste sumulants such as ash, machine oil and nitrate salts. The following laboratory-generated data indicate that all waste encapsulation materials tested are appropriate materials, for field in situ testing. Compressive strengths of treated Idaho National Engineering and Environment Laboratory (INEEL) soil and the waste encapsulation material were sufficient to prevent collapse of the void space in waste, i.e., greater than the NRC 60 psi minimum. The mineralogy and microstructure of hematite was amorphous but should progress to an interlocking crystalline solid. Phosphate was crystalline with characteristics of higher temperature ceramics. Paraffin is non crystalline but encapsulates even very fine grained INEEL soils. Each agent appears to be chemically and physically inert to possible waste materials such as, nitrates and machine cutting oil. Two of the agents hematite and phosphate react favorably with ash increasing the metals retention at higher waste loadings than Portland cement. Hematite, phosphate and zeolite decrease leaching of most hazardous metals from waste when compared to untreated waste and soil. Solution pH, time for reaction initiation, and viscosity values are conducive to jet-grouting application.

  2. Computed Tomography Imaging of Solid Tumors Using a Liposomal-Iodine Contrast Agent in Companion Dogs with Naturally Occurring Cancer

    PubMed Central

    Ghaghada, Ketan B.; Sato, Amy F.; Starosolski, Zbigniew A.; Berg, John; Vail, David M.

    2016-01-01

    Objectives Companion dogs with naturally occurring cancer serve as an important large animal model in translational research because they share strong similarities with human cancers. In this study, we investigated a long circulating liposomal-iodine contrast agent (Liposomal-I) for computed tomography (CT) imaging of solid tumors in companion dogs with naturally occurring cancer. Materials and Methods The institutional animal ethics committees approved the study and written informed consent was obtained from all owners. Thirteen dogs (mean age 10.1 years) with a variety of masses including primary and metastatic liver tumors, sarcomas, mammary carcinoma and lung tumors, were enrolled in the study. CT imaging was performed pre-contrast and at 15 minutes and 24 hours after intravenous administration of Liposomal-I (275 mg/kg iodine dose). Conventional contrast-enhanced CT imaging was performed in a subset of dogs, 90 minutes prior to administration of Liposomal-I. Histologic or cytologic diagnosis was obtained for each dog prior to admission into the study. Results Liposomal-I resulted in significant (p < 0.05) enhancement and uniform opacification of the vascular compartment. Non-renal, reticulo-endothelial systemic clearance of the contrast agent was demonstrated. Liposomal-I enabled visualization of primary and metastatic liver tumors. Sub-cm sized liver lesions grossly appeared as hypo-enhanced compared to the surrounding normal parenchyma with improved lesion conspicuity in the post-24 hour scan. Large liver tumors (> 1 cm) demonstrated a heterogeneous pattern of intra-tumoral signal with visibly higher signal enhancement at the post-24 hour time point. Extra-hepatic, extra-splenic tumors, including histiocytic sarcoma, anaplastic sarcoma, mammary carcinoma and lung tumors, were visualized with a heterogeneous enhancement pattern in the post-24 hour scan. Conclusions The long circulating liposomal-iodine contrast agent enabled prolonged visualization of small

  3. Natural product inspired diversity oriented synthesis of tetrahydroquinoline scaffolds as antitubercular agent.

    PubMed

    Kumar, Atul; Srivastava, Suman; Gupta, Garima; Chaturvedi, Vinita; Sinha, Sudhir; Srivastava, R

    2011-01-10

    An efficient natural product inspired diversity oriented syn thesis of tetrahydroquinoline analogues has been developed using the natural carbohydrate derived solid acid catalyst via multicomponent aza-Diels-Alder reaction of imine (generated in situ from aromatic amine and aldehyde) with dienophile in acetonitrile in a diastereoselective manner. The use of water as solvent reverses the diastereoselectivity toward the cis isomer. Interestingly, tricyclic pyrano/furano benzopyran with cis diastereoselectivity is obtained when salicylaldehyde is used as an alternative of aromatic aldehyde under the same condition. These synthesized quinolines and benzopyrans analogues have been evaluated for their Antitubercular activity against M. tuberculosis H₃₇Ra, and M. tuberculosis H₃₇Rv, and some of the analogues shows better activity profile than their natural product analogues. The protocol is not only mild, efficient, ecofriendly, but also involves reusable and biodegradable catalyst and provides route for both the diastereoisomer. PMID:21247127

  4. Marine natural products and their potential applications as anti-infective agents.

    PubMed

    Donia, Marwa; Hamann, Mark T

    2003-06-01

    The oceans are a unique resource that provide a diverse array of natural products, primarily from invertebrates such as sponges, tunicates, bryozoans, and molluscs, and from marine bacteria and cyanobacteria. As infectious diseases evolve and develop resistance to existing pharmaceuticals, the marine environment provides novel leads against fungal, parasitic, bacterial, and viral diseases. Many marine natural products have successfully advanced to the late stages of clinical trials, including dolastatin 10, ecteinascidin-743, kahalalide F, and aplidine, and a growing number of candidates have been selected as promising leads for extended preclinical assessment. Although many marine-product clinical trials are for cancer chemotherapy, drug resistance, emerging infectious diseases, and the threat of bioterrorism have all contributed to the interest in assessing natural ocean products in the treatment of infectious organisms. In this review, we focus on the pharmacologically tested marine leads that have shown in-vivo efficacy or potent in-vitro activity against infectious and parasitic diseases. PMID:12781505

  5. Harnessing nature's own cardiac defense mechanism with acadesine, an adenosine regulating agent: importance of the endothelium.

    PubMed

    Engler, R L

    1994-05-01

    Although the effects of adenosine on the heart, including the clinical suppression of cardiac arrhythmias, have been recognized for more than half a century, it is only in the last decade that the therapeutic potential of adenosine has been recognized. Research related to the clinical application of adenosine has concentrated on two areas. The first came directly from early observations about the use of adenosine in treating cardiac arrhythmias, in particular supraventricular tachycardias. The second relates to the use of adenosine to protect the heart from the deleterious consequences of myocardial ischemia and reperfusion. This review will focus on the latter cardioprotective properties of adenosine, particularly those shown by a novel group of drugs termed adenosine regulating agents, the prototype of which is acadesine (Protara).

  6. Safranal: From an Aromatic Natural Product to a Rewarding Pharmacological Agent

    PubMed Central

    Rezaee, Ramin; Hosseinzadeh, Hossein

    2013-01-01

    Safranal, the main component of Crocus sativus essential oil, is thought to be the main cause of saffron unique odor. It is now about eighty years that this compound has been discovered and since then different scientific experiments have been done investigating its biological-pharmacological activities. Safranal effects in CNS have been more attractive to scientists and an escalating number of papers have been published regarding its neuropsychological effects. These promising properties of safranal propose its presence as a therapeutic agent in future, although there is a great need for further clinical trials and toxicological studies. In this review article, according to Scopus ®, Thomson Reuters Web of Knowledge®, Scientific Information Database (SID) ® and Pubmed ® all papers published until July 2012 were thoroughly discussed and a brief note of each study was prepared. PMID:23638289

  7. Nonsteroidal anti-inflammatory drug activated gene-1 (NAG-1) modulators from natural products as anti-cancer agents.

    PubMed

    Yang, Min Hye; Kim, Jinwoong; Khan, Ikhlas A; Walker, Larry A; Khan, Shabana I

    2014-04-01

    Natural products are rich sources of gene modulators that may be useful in prevention and treatment of cancer. Recently, nonsteroidal anti-inflammatory drug (NSAID) activated gene-1 (NAG-1) has been focused as a target of action against diverse cancers like colorectal, pancreatic, prostate, and breast. A variety of natural agents have been reported to play a pivotal role in regulation of NAG-1 through multiple transcriptional mechanisms. The aim of this paper is to review the NAG-1 modulators derived from natural products including plants, marine organisms, and microorganisms. Plant extracts belonging to the families of Fabaceae (Astragalus membranaceus), Ranunculaceae (Coptis chinensis), Menispermaceae (Coscinium fenestratum), Umbelliferae (Pleurospermum kamtschaticum), Lamiaceae (Marubium vulgare), and Rosaceae (Prunus serotina) increased the protein expression of NAG-1 in human colon cancer or hepatocarcinoma cells. Phytochemicals in the class of flavonoids (apigenin, quercetin, isoliquiritigenin, and 2'-hydroxyflavanone), isoflavonoids (formononetin and genistein), catechins (epigallocatechin gallate and epicatechin gallate), stilbenoids (resveratrol and pinosylvin), phenolics (6-gingerol), phloroglucinols (rottlerin and aspidin PB), terpenoids (18 α-glycyrrhetinic acid, platycodin D, pseudolaric acid B, and xanthorrhizol), alkaloids (berberine, capsaicin, and indole-3-carbinol), lignans (isochaihulactone), anthraquinones (damnacanthal), and allyl sulfides (diallyl disulfide) elicited NAG-1 overexpression in various cancer cells. Pectenotoxin-2 from marine organisms and prodigiosin and anisomycin from microorganisms were also reported as NAG-1 modulators. Several transcription factors including EGR-1, p53, ATF-3, Sp1 and PPARγ were involved in natural products-induced NAG-1 transcriptional signaling pathway. PMID:24530873

  8. The evidence for natural therapeutics as potential anti-scarring agents in burn-related scarring.

    PubMed

    Mehta, M; Branford, O A; Rolfe, K J

    2016-01-01

    Though survival rate following severe thermal injuries has improved, the incidence and treatment of scarring have not improved at the same speed. This review discusses the formation of scars and in particular the formation of hypertrophic scars. Further, though there is as yet no gold standard treatment for the prevention or treatment of scarring, a brief overview is included. A number of natural therapeutics have shown beneficial effects both in vivo and in vitro with the potential of becoming clinical therapeutics in the future. These natural therapeutics include both plant-based products such as resveratrol, quercetin and epigallocatechin gallate as examples and includes the non-plant-based therapeutic honey. The review also includes potential mechanism of action for the therapeutics, any recorded adverse events and current administration of the therapeutics used. This review discusses a number of potential 'treatments' that may reduce or even prevent scarring particularly hypertrophic scarring, which is associated with thermal injuries without compromising wound repair. PMID:27574685

  9. The evidence for natural therapeutics as potential anti-scarring agents in burn-related scarring.

    PubMed

    Mehta, M; Branford, O A; Rolfe, K J

    2016-01-01

    Though survival rate following severe thermal injuries has improved, the incidence and treatment of scarring have not improved at the same speed. This review discusses the formation of scars and in particular the formation of hypertrophic scars. Further, though there is as yet no gold standard treatment for the prevention or treatment of scarring, a brief overview is included. A number of natural therapeutics have shown beneficial effects both in vivo and in vitro with the potential of becoming clinical therapeutics in the future. These natural therapeutics include both plant-based products such as resveratrol, quercetin and epigallocatechin gallate as examples and includes the non-plant-based therapeutic honey. The review also includes potential mechanism of action for the therapeutics, any recorded adverse events and current administration of the therapeutics used. This review discusses a number of potential 'treatments' that may reduce or even prevent scarring particularly hypertrophic scarring, which is associated with thermal injuries without compromising wound repair.

  10. Socio-Ecohydrologic Agents And Services: Integrating Human And Natural Components To Address Coupled System Resilience

    NASA Astrophysics Data System (ADS)

    Pavao-zuckerman, M.; Pope, A.; Chan, D.; Curl, K.; Gimblett, H. R.; Hough, M.; House-Peters, L.; Lee, R.; Scott, C. A.

    2012-12-01

    Riparian corridors in arid regions are highly valued for their relative scarcity, and because healthy riparian systems support high levels of biodiversity, can meet human demand for water and water-related resources and functions. Our team is taking a transdiciplinary social-ecological systems approach to assessing riparian corridor resilience in two watersheds (the San Pedro River in USA and Mexico, and the Rio San Miguel in Mexico) through a project funded by the NSF CNH program ("Strengthening Resilience of Arid Region Riparian Corridors"). Multiple perspectives are integrated in the project, including hydrology, ecology, institutional dynamics, and decision making (at the level of both policy and individual choice), as well as the perspectives of various stakeholder groups and individuals in the watersheds. Here we discuss initial findings that center around linking changes in ecohydrology and livelihoods related to decisions in response to climatic, ecological, and social change. The research team is implementing two approaches to integrate the disparate disciplines participating in the research (and the varied perspectives among the stakeholders in this binational riparian context): (1) ecosystem service assessment, and (2) agent based model simulation. We are developing an ecosystem service perspective that provides a bridge between ecological dynamics in the landscape and varied stakeholder perspectives on the implications of ecohydrology for well-being (economic, cultural, ecological). Services are linked on one hand to the spatial patterns of traits of individuals within species (allowing a more predictive application of ecosystem services as they vary with community change in time), and to stakeholder perspectives (facilitating integration of ecosystem services into our understanding of decision making processes) in a case study in the San Pedro River National Conservation Area. The agent- based model (ABM) approach incorporates the influence of human

  11. Cordycepin, a Natural Antineoplastic Agent, Induces Apoptosis of Breast Cancer Cells via Caspase-dependent Pathways.

    PubMed

    Wang, Di; Zhang, Yongfeng; Lu, Jiahui; Wang, Yang; Wang, Junyue; Meng, Qingfan; Lee, Robert J; Wang, Di; Teng, Lesheng

    2016-01-01

    Cordycepin, a major compound separated from Cordyceps sinensis, is known as a potential novel candidate for cancer therapy. Breast cancer, the most typical cancer diagnosed among women, remains a global health problem. In this study, the anti-breast cancer property of cordycepin and its underlying mechanisms was investigated. The direct effects of cordycepin on breast cancer cells both in in vitro and in vivo experiments were evaluated. Cordycepin exerted cytotoxicity in MCF-7 and MDA-MB-231 cells confirmed by reduced cell viability, inhibition of cell proliferation, enhanced lactate dehydrogenase release and reactive oxygen species accumulation, induced mitochondrial dysfunction and nuclear apoptosis in human breast cancer cells. Cordycepin increased the activation of pro-apoptotic proteins, including caspase-8, caspase-9, caspase-3 and Bax, and suppressed the expression of the anti-apoptotic protein, B-cell lymphoma 2 (Bcl-2). The inhibition on MCF-7-xenografted tumor growth in nude mice further confirmed cordycepin's anti-breast cancer effect. These aforementioned results reveal that cordycepin induces apoptosis in human breast cancer cells via caspase-dependent pathways. The data shed light on the possibility of cordycepin being a safe agent for breast cancer treatment. PMID:26996021

  12. Dissolution kinetics of Pd and Pt from automobile catalysts by naturally occurring complexing agents.

    PubMed

    Sebek, Ondřej; Mihaljevič, Martin; Strnad, Ladislav; Ettler, Vojtěch; Ježek, Josef; Stědrý, Robin; Drahota, Petr; Ackerman, Lukáš; Adamec, Vladimír

    2011-12-30

    Powder samples prepared from gasoline (Pt, Pd, Rh, new GN/old GO) and diesel (Pt, new DN/old DO) catalysts and recycled catalyst NIST 2556 were tested using kinetic leaching experiments following 1, 12, 24, 48, 168, 360, 720 and 1440-h interactions with solutions of 20mM citric acid (CA), 20 mM Na(2)P(4)O(7) (NaPyr), 1 g L(-1) NaCl (NaCl), a fulvic acid solution (FA-DOC 50 mg L(-1)) and 20 mM CA at pH 3, 4, 5, 6, 7, 8 and 9. The mobilisation of platinum group elements (PGEs) was fastest in solutions of CA and NaPyr. In the other interactions (NaCl, FA), the release of PGEs was probably followed by immobilisation processes, and the interactions were not found to correspond to the simple release of PGEs into solution. Because of their low concentrations, the individual complexing agents did not have any effect on the speciation of Pd and Pt in the extracts; both metals are present in solution as the complexes Me(OH)(2), Me(OH)(+). Immobilisation can take place through the adsorption of the positively charged hydroxyl complexes or flocculation of fulvic acid, complexing the PGEs on the surface of the extracted catalysts. The calculated normalised bulk released NRi values are similar to the reaction rate highest in the solutions of CA and NaPyr. PMID:22078491

  13. Natural lignans from Arctium lappa as antiaging agents in Caenorhabditis elegans.

    PubMed

    Su, Shan; Wink, Michael

    2015-09-01

    Arctium lappa is a well-known traditional medicinal plant in China (TCM) and Europe that has been used for thousands of years to treat arthritis, baldness or cancer. The plant produces lignans as secondary metabolites, which have a wide range of bioactivities. Yet, their antiaging potential has not been explored. In this study, we isolated six lignans from A. lappa seeds, namely arctigenin, matairesinol, arctiin, (iso)lappaol A, lappaol C, and lappaol F. The antioxidant and antiaging properties of the isolated lignans were studied using Caenorhabditis elegans as a relevant animal model. All lignans at concentrations of 10 and 100 μM significantly extended the mean life span of C. elegans. The strongest effect was observed with matairesinol, which at a concentration of 100 μM extended the life span of worms by 25%. Additionally, we observed that five lignans are strong free radical-scavengers in vitro and in vivo and all lignans can improve survival of C. elegans under oxidative stress. Furthermore, the lignans can induce the nuclear translocation of the transcription factor DAF-16 and up-regulate its expression, suggesting that a possible underlying mechanism of the observed longevity-promoting activity of lignans depends on DAF-16 mediated signaling pathway. All lignans up-regulated the expression of jnk-1, indicating that lignans may promote the C. elegans longevity and stress resistance through a JNK-1-DAF-16 cascade. Our study reports new antiaging activities of lignans, which might be candidates for developing antiaging agents.

  14. Natural lignans from Arctium lappa as antiaging agents in Caenorhabditis elegans.

    PubMed

    Su, Shan; Wink, Michael

    2015-09-01

    Arctium lappa is a well-known traditional medicinal plant in China (TCM) and Europe that has been used for thousands of years to treat arthritis, baldness or cancer. The plant produces lignans as secondary metabolites, which have a wide range of bioactivities. Yet, their antiaging potential has not been explored. In this study, we isolated six lignans from A. lappa seeds, namely arctigenin, matairesinol, arctiin, (iso)lappaol A, lappaol C, and lappaol F. The antioxidant and antiaging properties of the isolated lignans were studied using Caenorhabditis elegans as a relevant animal model. All lignans at concentrations of 10 and 100 μM significantly extended the mean life span of C. elegans. The strongest effect was observed with matairesinol, which at a concentration of 100 μM extended the life span of worms by 25%. Additionally, we observed that five lignans are strong free radical-scavengers in vitro and in vivo and all lignans can improve survival of C. elegans under oxidative stress. Furthermore, the lignans can induce the nuclear translocation of the transcription factor DAF-16 and up-regulate its expression, suggesting that a possible underlying mechanism of the observed longevity-promoting activity of lignans depends on DAF-16 mediated signaling pathway. All lignans up-regulated the expression of jnk-1, indicating that lignans may promote the C. elegans longevity and stress resistance through a JNK-1-DAF-16 cascade. Our study reports new antiaging activities of lignans, which might be candidates for developing antiaging agents. PMID:26141518

  15. Natural therapeutic agents for neurodegenerative diseases from a traditional herbal medicine Pongamia pinnata (L.) Pierre.

    PubMed

    Li, Jiayuan; Jiang, Zhe; Li, Xuezheng; Hou, Yue; Liu, Fen; Li, Ning; Liu, Xia; Yang, Lihua

    2015-01-01

    Neurodegenerative diseases are associated with neuroinflammation, manifested by over-production of nitric oxide (NO) by microglial cells. Now there still lack effective treatment and prevention for the neurodegenerative diseases. Concerning neuroinflammation mediated by microglia cell, bioactivity-guided phytochemical research of Pongamia pinnata (L.) Pierre was performed in this study. A new chlorinated flavonoid, 2′,6′-dichlore-3′, 5′-dimethoxy-[2′′,3′′:7,8]-furanoflavone (1) was identified together with 29 known compounds, including flavonoids (compounds 2-17), isoflavonoids (compounds 18-23), chalcones (compounds 24-25), flavonones (compounds 26-27), triterpenes (28-29) and alkaloid (30) from the effective dichloride methane extract of dry stem of P. pinnata (L.) Pierre. Their structures were elucidated by physicochemical and spectral methods. The anti-neuroinflammatory activities were assayed in BV-2 cells by assessing LPS-induced NO production. Then pongaglabol methyl ether (2), lonchocarpin (24) and glabrachromene II (25) were selected as potential therapeutic agents for neurodegenerative diseases because of their significant anti-neuroinflammatory activities. Furthermore, the characteristics of structure type existing in P. pinnata (L.) Pierre and brief SAR were summarized, respectively.

  16. Natural therapeutic agents for neurodegenerative diseases from a traditional herbal medicine Pongamia pinnata (L.) Pierre.

    PubMed

    Li, Jiayuan; Jiang, Zhe; Li, Xuezheng; Hou, Yue; Liu, Fen; Li, Ning; Liu, Xia; Yang, Lihua

    2015-01-01

    Neurodegenerative diseases are associated with neuroinflammation, manifested by over-production of nitric oxide (NO) by microglial cells. Now there still lack effective treatment and prevention for the neurodegenerative diseases. Concerning neuroinflammation mediated by microglia cell, bioactivity-guided phytochemical research of Pongamia pinnata (L.) Pierre was performed in this study. A new chlorinated flavonoid, 2′,6′-dichlore-3′, 5′-dimethoxy-[2′′,3′′:7,8]-furanoflavone (1) was identified together with 29 known compounds, including flavonoids (compounds 2-17), isoflavonoids (compounds 18-23), chalcones (compounds 24-25), flavonones (compounds 26-27), triterpenes (28-29) and alkaloid (30) from the effective dichloride methane extract of dry stem of P. pinnata (L.) Pierre. Their structures were elucidated by physicochemical and spectral methods. The anti-neuroinflammatory activities were assayed in BV-2 cells by assessing LPS-induced NO production. Then pongaglabol methyl ether (2), lonchocarpin (24) and glabrachromene II (25) were selected as potential therapeutic agents for neurodegenerative diseases because of their significant anti-neuroinflammatory activities. Furthermore, the characteristics of structure type existing in P. pinnata (L.) Pierre and brief SAR were summarized, respectively. PMID:25466192

  17. SuperSweet—a resource on natural and artificial sweetening agents

    PubMed Central

    Ahmed, Jessica; Preissner, Saskia; Dunkel, Mathias; Worth, Catherine L.; Eckert, Andreas; Preissner, Robert

    2011-01-01

    A vast number of sweet tasting molecules are known, encompassing small compounds, carbohydrates, d-amino acids and large proteins. Carbohydrates play a particularly big role in human diet. The replacement of sugars in food with artificial sweeteners is common and is a general approach to prevent cavities, obesity and associated diseases such as diabetes and hyperlipidemia. Knowledge about the molecular basis of taste may reveal new strategies to overcome diet-induced diseases. In this context, the design of safe, low-calorie sweeteners is particularly important. Here, we provide a comprehensive collection of carbohydrates, artificial sweeteners and other sweet tasting agents like proteins and peptides. Additionally, structural information and properties such as number of calories, therapeutic annotations and a sweetness-index are stored in SuperSweet. Currently, the database consists of more than 8000 sweet molecules. Moreover, the database provides a modeled 3D structure of the sweet taste receptor and binding poses of the small sweet molecules. These binding poses provide hints for the design of new sweeteners. A user-friendly graphical interface allows similarity searching, visualization of docked sweeteners into the receptor etc. A sweetener classification tree and browsing features allow quick requests to be made to the database. The database is freely available at: http://bioinformatics.charite.de/sweet/. PMID:20952410

  18. Microbial Content of Nonsterile Therapeutic Agents Containing Natural or Seminatural Active Ingredients

    PubMed Central

    Schiller, I.; Kuntscher, H.; Wolff, A.; Nekola, M.

    1968-01-01

    The relationship was investigated between various chemical or pharmaceutical production processes and the extent of microbial contamination, of natural origin, of the resulting products. The products contained active ingredients of vegetable, enzymatic, or animal origin. It was concluded that (i) vegetable products practically free from microbes can be produced if the proper manufacturing steps are taken; (ii) sterilization of the media used to manufacture antibiotics, etc., produces products with little contamination; and (iii) products containing extracts of animal organs require careful refrigeration and addition of preservatives to produce acceptable levels of microbial contamination. PMID:5726165

  19. Natural selection for 2,4,5-trichlorophenoxyacetic acid mineralizing bacteria in agent orange contaminated soil.

    PubMed

    Rice, J F; Menn, F M; Hay, A G; Sanseverino, J; Sayler, G S

    2005-12-01

    Agent Orange contaminated soils were utilized in direct enrichment culture studies to isolate 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4-dichlorophenoxyacetic acid (2,4-D) mineralizing bacteria. Two bacterial cultures able to grow at the expense of 2,4,5-T and/or 2,4-D were isolated. The 2,4,5-T degrading culture was a mixed culture containing two bacteria, Burkholderia species strain JR7B2 and Burkholderia species strain JR7B3. JR7B3 was able to metabolize 2,4,5-T as the sole source of carbon and energy, and demonstrated the ability to affect metabolism of 2,4-D to a lesser degree. Strain JR7B3 was able to mineralize 2,4,5-T in pure culture and utilized 2,4,5-T in the presence of 0.01% yeast extract. Subsequent characterization of the 2,4-D degrading culture showed that one bacterium, Burkholderia species strain JRB1, was able to utilize 2,4-D as a sole carbon and energy source in pure culture. Polymerase chain reaction (PCR) experiments utilizing known genetic sequences from other 2,4-D and 2,4,5-T degrading bacteria demonstrated that these organisms contain gene sequences similar to tfdA, B, C, E, and R (Strain JRB1) and the tftA, C, and E genes (Strain JR7B3). Expression analysis confirmed that tftA, C, and E and tfdA, B, and C were transcribed during 2,4,5-T and 2,4-D dependent growth, respectively. The results indicate a strong selective pressure for 2,4,5-T utilizing strains under field condition. PMID:15865343

  20. Natural selection for 2,4,5-trichlorophenoxyacetic acid mineralizing bacteria in agent orange contaminated soil.

    PubMed

    Rice, J F; Menn, F M; Hay, A G; Sanseverino, J; Sayler, G S

    2005-12-01

    Agent Orange contaminated soils were utilized in direct enrichment culture studies to isolate 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4-dichlorophenoxyacetic acid (2,4-D) mineralizing bacteria. Two bacterial cultures able to grow at the expense of 2,4,5-T and/or 2,4-D were isolated. The 2,4,5-T degrading culture was a mixed culture containing two bacteria, Burkholderia species strain JR7B2 and Burkholderia species strain JR7B3. JR7B3 was able to metabolize 2,4,5-T as the sole source of carbon and energy, and demonstrated the ability to affect metabolism of 2,4-D to a lesser degree. Strain JR7B3 was able to mineralize 2,4,5-T in pure culture and utilized 2,4,5-T in the presence of 0.01% yeast extract. Subsequent characterization of the 2,4-D degrading culture showed that one bacterium, Burkholderia species strain JRB1, was able to utilize 2,4-D as a sole carbon and energy source in pure culture. Polymerase chain reaction (PCR) experiments utilizing known genetic sequences from other 2,4-D and 2,4,5-T degrading bacteria demonstrated that these organisms contain gene sequences similar to tfdA, B, C, E, and R (Strain JRB1) and the tftA, C, and E genes (Strain JR7B3). Expression analysis confirmed that tftA, C, and E and tfdA, B, and C were transcribed during 2,4,5-T and 2,4-D dependent growth, respectively. The results indicate a strong selective pressure for 2,4,5-T utilizing strains under field condition.

  1. Natural populations of Trypanosoma cruzi, the agent of Chagas disease, have a complex multiclonal structure

    SciTech Connect

    Tibayrenc, M.; Ward, P.; Moya, A.; Ayala, F.J.

    1986-01-01

    The authors have studied 15 gene loci coding for enzymes in 121 Trypanosoma cruzi stocks from a wide geographic range - from the US and Mexico to Chile and southern Brazil. T.cruzi is diploid but reproduction is basically clonal, with very little if any sexuality remaining at present. They have identified 43 different clones by their genetic composition; the same genetic clone is often found in very distant places and in diverse hosts. There is much genetic heterogeneity among the different clones, and they cannot be readily classified into a few discrete groups that might represent natural taxa. These findings imply that the biological and medical characteristics need to be ascertained separately for each natural clone. The evidence indicates that clonal evolution is very ancient in T.cruzi. The authors propose two alternative hypotheses concerning the relationship between the biochemical diversity and the heterogeneity in other biological and medical characteristics of T. cruzi. One hypothesis is that the degree of diversity between strains simply reflects the time elapsed since their last common ancestor. The second hypothesis is that biological and medical heterogeneity is recent and reflects adaptation to different transmission cycles. A decision between the two hypotheses can be reached with appropriate studies, with important medical consequences.

  2. The use of ozone as an oxidizing agent to evaluate antioxidant activities of natural substrates.

    PubMed

    He, Q C; Krone, K; Scherl, D; Kotler, M; Tavakkol, A

    2004-01-01

    Ozone, the main component of photochemical smog and air pollution, can damage the skin by oxidizing stratum corneum enzymes, lipids and structural proteins. We have developed a rapid screening assay to determine free radical scavenging capacity of various active ingredients that are frequently used in personal care products. Several known antioxidants including vitamin C, vitamin E analog Trolox, walnut seed extract, lipoic acid and ergothioneine inner salt were assayed for their ability to neutralize ozone-induced oxidation of beta-phycoerythrin, a fluorescent reporter protein derived from algae. The free radical scavenging capacities of these antioxidants were quantified and compared. The results demonstrate that this assay is a valuable primary screening tool for identifying antioxidant activity of natural or synthetic substrates that can be used in personal care products to protect the uppermost layer of our skin from oxidizing damage induced by O3.

  3. Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitors from Natural Products: Discovery of Next-Generation Antihyperglycemic Agents.

    PubMed

    Choi, Chang-Ik

    2016-01-01

    Diabetes mellitus is a chronic condition associated with the metabolic impairment of insulin actions, leading to the development of life-threatening complications. Although many kinds of oral antihyperglycemic agents with different therapeutic mechanisms have been marketed, their undesirable adverse effects, such as hypoglycemia, weight gain, and hepato-renal toxicity, have increased demand for the discovery of novel, safer antidiabetic drugs. Since the important roles of the sodium-glucose cotransporter 2 (SGLT2) for glucose homeostasis in the kidney were recently elucidated, pharmacological inhibition of SGLT2 has been considered a promising therapeutic target for the treatment of type 2 diabetes. Since the discovery of the first natural SGLT2 inhibitor, phlorizin, several synthetic glucoside analogs have been developed and introduced into the market. Furthermore, many efforts to find new active constituents with SGLT2 inhibition from natural products are still ongoing. This review introduces the history of research on the development of early-generation SGLT2 inhibitors, and recent progress on the discovery of novel candidates for SGLT2 inhibitor from several natural products that are widely used in traditional herbal medicine. PMID:27618891

  4. The effects of spinosad, a naturally derived insect control agent, to the honeybee (Apis melifera).

    PubMed

    Miles, M; Mayes, M; Dutton, R

    2002-01-01

    Spinosad is a novel insect control agent derived by fermentation of the Actinomycete bacterium, Saccharopolyspora spinosa. Spinosad controls many caterpillar pests in vines, pome fruit and vegetables (including tomatoes and peppers), thrips in tomatoes, peppers and ornamental cultivation and dipterous leafminers in vegetables and ornamentals. Application rates vary between 25 to 100 g of active substance per hectare (g as/ha) and 4.8 to 36 g of active substance per hectolitre (g as/hL) depending on the crop and target pest. It is important that plant protection products are authorized for use only in ways that do not pose an unacceptable risk of harm to honeybees. For this purpose testing was performed to enable the safety of spinosad to be evaluated. The effects of spinosad to honeybees have been extensively researched. Testing has been performed under a variety of conditions in a range of countries globally. Studies to determine the acute toxicity of spinosad under laboratory conditions were conducted to generate LD50 or LC50 values for oral and contact routes of administration. These demonstrated that spinosad was highly toxic to worker honeybees under worst case laboratory conditions and that the oral route of exposure provided the greater risk. Residue tests conducted under laboratory, semi-field and field conditions on worker honeybees foraging on treated foliage indicated that dry product residues were harmless. Therefore the effects seen in the laboratory acute toxicity tests did not translate to a more realistic exposure scenario indicating that safe use patterns for the product can be developed. Semi-field cage studies have also demonstrated that spinosad was safe to bees when applied to flowering crops during periods of bee activity. The majority of studies conducted have indicated that spinosad does not adversely affect honeybee behaviour, brood or queen. It can be concluded that spinosad when used according to the approved product label recommendations

  5. Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer-Part 2.

    PubMed

    Sagar, S M; Yance, D; Wong, R K

    2006-06-01

    The herbalist has access to hundreds of years of observational data on the anticancer activity of many herbs. Laboratory studies are expanding the clinical knowledge that is already documented in traditional texts. The herbs that are traditionally used for anti-cancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclo-oxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose-response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or as adaptogens, potentially enhancing the efficacy of the conventional therapies or reducing toxicity. Their effectiveness may be increased when multiple agents are used in optimal combinations. New designs for trials to demonstrate activity in human subjects are required. Although controlled trials may be preferable, smaller studies with appropriate endpoints and

  6. Preliminary investigation of topical nitroglycerin formulations containing natural wound healing agent in diabetes-induced foot ulcer.

    PubMed

    Hotkar, Mukesh S; Avachat, Amelia M; Bhosale, Sagar S; Oswal, Yogesh M

    2015-04-01

    Nitroglycerin (NTG) is an organic nitrate rapidly denitrated by enzymes to release free radical nitric oxide and shows improved wound healing and tissue protection from oxidative damage. The purpose of this study was to evaluate whether topical application of NTG in the form of gel/ointment along with a natural wound healing agent, aloe vera, would bring about wound healing by using diabetes-induced foot ulcer model and rat excision wound model. All these formulations were evaluated for pH, viscosity, drug content and ex vivo diffusion studies using rat skin. Based on ex vivo permeation studies, the formulation consisting of carbopol 974p as a gelling agent and aloe vera was found to be suitable. The in vivo study used streptozotocin-induced diabetic foot ulcer and rat excision wound models to analyse wound healing activity. The wound size in animals of all treated groups was significantly reduced compared with that of the diabetic control and marketed treated animals. This study showed that the gel formed with carbopol 974p (1%) and aloe vera promotes significant wound healing and closure in diabetic rats compared with the commercial product and provides a promising product to be used in diabetes-induced foot ulcer.

  7. Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer—Part 1

    PubMed Central

    Sagar, S.M.; Yance, D.; Wong, R.K.

    2006-01-01

    An integrative approach for managing a patient with cancer should target the multiple biochemical and physiologic pathways that support tumour development and minimize normal-tissue toxicity. Angiogenesis is a key process in the promotion of cancer. Many natural health products that inhibit angiogenesis also manifest other anticancer activities. The present article focuses on products that have a high degree of anti-angiogenic activity, but it also describes some of the many other actions of these agents that can inhibit tumour progression and reduce the risk of metastasis. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclooxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. The herbs that are traditionally used for anticancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose–response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy, they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or

  8. Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer-Part 1.

    PubMed

    Sagar, S M; Yance, D; Wong, R K

    2006-02-01

    An integrative approach for managing a patient with cancer should target the multiple biochemical and physiologic pathways that support tumour development and minimize normal-tissue toxicity. Angiogenesis is a key process in the promotion of cancer. Many natural health products that inhibit angiogenesis also manifest other anticancer activities. The present article focuses on products that have a high degree of anti-angiogenic activity, but it also describes some of the many other actions of these agents that can inhibit tumour progression and reduce the risk of metastasis. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclooxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. The herbs that are traditionally used for anticancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose-response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy, they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or as

  9. Light-responsive polymer microcapsules as delivery systems for natural active agents

    NASA Astrophysics Data System (ADS)

    Bizzarro, Valentina; Carfagna, Cosimo; Cerruti, Pierfrancesco; Marturano, Valentina; Ambrogi, Veronica

    2016-05-01

    In this work we report the preparation and the release behavior of UV-responsive polymeric microcapsules containing essential oils as a core. The oil acted also as a monomer solvent during polymerization. Accordingly, the potentially toxic organic solvent traditionally used was replaced with a natural active substance, resulting in a more sustainable functional system. Polymer shell was based on a lightly cross-linked polyamide containing UV-sensitive azobenzene moieties in the main chain. The micro-sized capsules were obtained via interfacial polycondensation in o/w emulsion, and their mean size was measured via Dynamic Light Scattering. Shape and morphology were analyzed through Scanning Electron and Optical Microscopy. UV-responsive behavior was evaluated via spectrofluorimetry, by assessing the release kinetics of a fluorescent probe molecule upon UV light irradiation (λmax=360 nm). The irradiated samples showed an increase in fluorescence intensity, in accordance with the increase of the probe molecule concentration in the release medium. As for the un-irradiated sample, no changes could be detected demonstrating the effectiveness of the obtained releasing system.

  10. Effect of tea tree (Melaleuca alternifolia) oil as a natural antimicrobial agent in lipophilic formulations.

    PubMed

    Mantil, Elisabeth; Daly, Grace; Avis, Tyler J

    2015-01-01

    There has been increased interest surrounding the use of tea tree oil (TTO) as a natural antimicrobial. In this study, the antimicrobial activity of TTO and its components were investigated in vitro and in a predominantly lipid-based personal care formulation. In vitro, TTO showed minimal inhibitory concentrations of 0.2% (for Saccharomyces cerevisiae and Pythium sulcatum), 0.4% (for Escherichia coli, Bacillus subtilis, and Rhizopus stolonifer), and 0.8% (for Botrytis cinerea). TTO at 0.08%-0.8% was often as efficient as parabens. Comparison of the antimicrobial activities of TTO components showed that terpinen-4-ol and γ-terpinene were generally most effective in inhibiting microbial growth. TTO activity in a personal care product was evaluated through air and water exposure, artificial inoculation, and shelf life studies. While TTO did not increase shelf life of unopened products, it decreased microbial load in products exposed to water and air. Results from this study support that antimicrobial activity of TTO can be attributed to varying levels of its components and that low levels of TTO were effective in reducing microbial growth during the use of the product. This study showed that TTO can act as a suitable preservative system within an oil-based formulation.

  11. Human Hair as a Natural Sun Protection Agent: A Quantitative Study.

    PubMed

    de Gálvez, María Victoria; Aguilera, José; Bernabó, Jean-Luc; Sánchez-Roldán, Cristina; Herrera-Ceballos, Enrique

    2015-01-01

    The rising incidence of skin cancers attributable to excessive sun exposure has become a major health concern worldwide. While numerous studies have analyzed the sun protective effect of sunscreens, clothing and antioxidants, none to date have measured the photoprotective effect of hair, despite clinical evidence that individuals with balding or thinning hair are at greater risk of skin lesions that can progress to cancer, hence the recommendation to use hats or umbrellas. We analyzed the level of protection offered by hair according to hair density, thickness and color using the spectral transmittance and corrected for relative erythema effectiveness. Our results show that hair provides a barrier against both UVB and UVA radiation which is significantly increased with respect to the hair density, thickness and the presence of melanins. This is the first study to quantify sun protection factor offered by hair, namely hair ultraviolet protection factor (HUPF). We believe that hair should be recognized as an important natural sun barrier in the prevention of UV-induced skin cancers. PMID:25682789

  12. Identification of a new degradation product of the antifouling agent Irgarol 1051 in natural samples

    USGS Publications Warehouse

    Ferrer, I.; Barcelo, D.

    2001-01-01

    A main degradation product of Irgarol [2-(methylthio)-4-(tert-butylamino)-6-(cyclopropylamino)-s-triazine], one of the most widely used compounds in antifouling paints, was detected at trace levels in seawater and sediment samples collected from several marinas on the Mediterranean coast. This degradation product was identified as 2-methylthio-4-tert-butylamino-s-triazine. The unequivocal identification of this compound in seawater samples was carried out by solid-phase extraction (SPE) coupled on-line with liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS). SPE was carried out by passing 150 ml of seawater sample through a cartridge containing a polymeric phase (PLRP-s), with recoveries ranging from 92 to 108% (n=5). Using LC-MS detection in positive ion mode, useful structural information was obtained by increasing the fragmentor voltage, thus permitting the unequivocal identification of this compound in natural samples. Method detection limits were in the range of 0.002 to 0.005 ??g/l. Overall, the combination of on-line SPE and LC-APCI-MS represents an important advance in environmental analysis of herbicide degradation products in seawater, since it demonstrates that trace amounts of new polar metabolites may be determined rapidly. This paper reports the LC-MS identification of the main degradation product of Irgarol in seawater and sediment samples. ?? 2001 Elsevier Science B.V. All rights reserved.

  13. [Evaluation of pharmacopoeia methods for determination of antimicrobial agents, especially of natural substances].

    PubMed

    Brantner, A

    1997-01-01

    Microbiological assays referring to antibiotics were first mentioned in 1955 in the US Pharmacopedia XV and in the Pharmacopedia of India I. In the pharmacopedias two general methods are employed: The first group of methods is grounded on diffusion (disc assay, cylinder-plate and hole-plate assay), the second one is based on the determination of optical density (turbidimetric method). Both methods involve certain problems, particularly with respect to the testing of low-active natural substances. In the course of our investigations those test methods were evaluated and the advantages and disadvantages discussed. The methods were compared to test systems not being described in the pharmacopedias (microdilution test, bioautographic TLC assay). In addition to that we examined spectrophotometrically (OD580nm) the influence of an antimicrobial substance and of a solutizer on the bacterial growth. Tetracycline hydrochloride was used as reference and naringenin as test substance. The results were analyzed with statistical methods cited in the pharmacopedias, e.g. straight-line method and compared to other common methods, e.g. analysis of variance.

  14. Effect of tea tree (Melaleuca alternifolia) oil as a natural antimicrobial agent in lipophilic formulations.

    PubMed

    Mantil, Elisabeth; Daly, Grace; Avis, Tyler J

    2015-01-01

    There has been increased interest surrounding the use of tea tree oil (TTO) as a natural antimicrobial. In this study, the antimicrobial activity of TTO and its components were investigated in vitro and in a predominantly lipid-based personal care formulation. In vitro, TTO showed minimal inhibitory concentrations of 0.2% (for Saccharomyces cerevisiae and Pythium sulcatum), 0.4% (for Escherichia coli, Bacillus subtilis, and Rhizopus stolonifer), and 0.8% (for Botrytis cinerea). TTO at 0.08%-0.8% was often as efficient as parabens. Comparison of the antimicrobial activities of TTO components showed that terpinen-4-ol and γ-terpinene were generally most effective in inhibiting microbial growth. TTO activity in a personal care product was evaluated through air and water exposure, artificial inoculation, and shelf life studies. While TTO did not increase shelf life of unopened products, it decreased microbial load in products exposed to water and air. Results from this study support that antimicrobial activity of TTO can be attributed to varying levels of its components and that low levels of TTO were effective in reducing microbial growth during the use of the product. This study showed that TTO can act as a suitable preservative system within an oil-based formulation. PMID:25515896

  15. [Impact of effect of natural disasters on the circulation of causative agents of parasitic diseases].

    PubMed

    Vaserin, Iu I; Khromenkova, E P; Dimidova, L L; Tverdokhlebova, T I; Nagornyĭ, S A; Prokopova, L V; Dumbadze, O S; Murashov, N E; Butaev, T M; Agirov, A Kh; Osmolovskiĭ, S V; Papatsenko, L B; Soldatova, M V

    2005-01-01

    The southern region is marked by a high incidence of parasitic diseases and a significant contamination of environmental objects with the eggs and cysts of their pathogens. Background examinations revealed the greatest soil contamination with helminthic eggs in the Temryuksky District of the Krasnodar Territory and in the towns of Vladikavkaz and Digora of the Republic of North Ossetia (Alania). The least contamination was found in Rostov-on-Don and the towns of the south-western area of the Krasnodar Territory. The eggs of Toxocara and astamination. There is an increase in the proportion of soil positive tests from 26.6 to 50.0, with the high (up to 82.0-100.0%) viability of eggs and a rise in the intensive index of their content per kg of soil (from 2.7 to 4.7-11.0). Toxocara eggs were mainly detected. The established high proportion of seropositive persons (10.7-18.0%) among the local population is an additional verification of the wide circulation of Toxocara eggs in nature. By the helminthic egg contamination index, the soils of localities of the south of Russia are qualified as those of moderate epidemic hazard. The floods accompanied by the increased helminthological contamination of the upper soil layer may lead to a higher human risk for contamination with helminthic diseases. PMID:16445230

  16. Synthetic glycolipid activators of natural killer T cells as immunotherapeutic agents

    PubMed Central

    Carreño, Leandro J; Saavedra-Ávila, Noemí A; Porcelli, Steven A

    2016-01-01

    Certain types of glycolipids have been found to have remarkable immunomodulatory properties as a result of their ability to activate specific T lymphocyte populations with an extremely wide range of immune effector properties. The most extensively studied glycolipid reactive T cells are known as invariant natural killer T (iNKT) cells. The antigen receptors of these cells specifically recognize certain glycolipids, most notably glycosphingolipids with α-anomeric monosaccharides, presented by the major histocompatibility complex class I-like molecule CD1d. Once activated, iNKT cells can secrete a very diverse array of pro- and anti-inflammatory cytokines to modulate innate and adaptive immune responses. Thus, glycolipid-mediated activation of iNKT cells has been explored for immunotherapy in a variety of disease states, including cancer and a range of infections. In this review, we discuss the design of synthetic glycolipid activators for iNKT cells, their impact on adaptive immune responses and their use to modulate iNKT cell responses to improve immunity against infections and cancer. Current challenges in translating results from preclinical animal studies to humans are also discussed. PMID:27195112

  17. Natural products as anti-glycation agents: possible therapeutic potential for diabetic complications.

    PubMed

    Elosta, Abdulhakim; Ghous, Tahseen; Ahmed, Nessar

    2012-03-01

    Diabetes mellitus is characterised by hyperglycaemia, lipidaemia and oxidative stress and predisposes affected individuals to long-term complications afflicting the eyes, skin, kidneys, nerves and blood vessels. Increased protein glycation and the subsequent build-up of tissue advanced glycation endproducts (AGEs) contribute towards the pathogenesis of diabetic complications. Protein glycation is accompanied by generation of free radicals through autoxidation of glucose and glycated proteins and via interaction of AGEs with their cell surface receptors (referred to as RAGE). Glycationderived free radicals can damage proteins, lipids and nucleic acids and contribute towards oxidative stress in diabetes. There is interest in compounds with anti-glycation activity as they may offer therapeutic potential in delaying or preventing the onset of diabetic complications. Although many different compounds are under study, only a few have successfully entered clinical trials but none have yet been approved for clinical use. Whilst the search for new synthetic inhibitors of glycation continues, little attention has been paid to anti-glycation compounds from natural sources. In the last few decades the traditional system of medicine has become a topic of global interest. Various studies have indicated that dietary supplementation with combined anti-glycation and antioxidant nutrients may be a safe and simple complement to traditional therapies targeting diabetic complications. Data for forty two plants/constituents studied for anti-glycation activity is presented in this review and some commonly used medicinal plants that possess anti-glycation activity are discussed in detail including their active ingredients, mechanism of action and therapeutic potential. PMID:22268395

  18. Effects of different stressor agents on gilthead seabream natural cytotoxic activity.

    PubMed

    Cuesta, Alberto; Angeles Esteban, M; Meseguer, José

    2003-11-01

    Several common situations in gilthead seabream (Sparus aurata L.) farming, such as air exposure, crowding and the use of anaesthetics, have been demonstrated to be stressful. In the present study, these conditions were simulated in the laboratory, after which head-kidney natural cytotoxic cell (NCC) activity was evaluated. For this, several specimens were air exposed for 2 min, returned to the aquarium and sampled from 0 to 4 days after exposure. NCC activity was significantly lower on the day following air-exposure compared with the control (rested fish) but not at any other time studied. Other fish were crowded (100 kg biomass m(-3), 2 h), returned to an aquarium with the same density as the control group (9 kg m(-3)) and sampled from 0 to 4 days after treatment. Head-kidney NCC activity was statistically increased compared with the control (resting) fish, 1 day after crowding. Anaesthesis for 1 h with 60 or 200 microl 2-phenoxyethanol l(-1)had no significant effect on NCC activity, while the use of 50 mg MS222 l(-1)for 1 h reduced such activity (by about 40%) compared with the control. In other experiments, fish were consecutively treated with crowding and anaesthetics. When treated with the lowest 2-phenoxyethanol concentration after crowding, the NCC activity inhibition was abolished compared with the activity in fish treated either with crowding or anaesthetic alone, while the use of the highest concentration increased such inhibition. The use of MS222 after crowding did not produce any differential effect compared with the fish treated with only one of the factors. In conclusion, NCC activity is affected differently according to the stress factor applied (hypoxia, crowding and/or anaesthetics). Differences in the effects provoked by these stressors on other seabream innate immune parameters are discussed.

  19. Role of rat strain in the differential sensitivity to pharmaceutical agents and naturally occurring substances.

    PubMed

    Kacew, S; Festing, M F

    1996-01-01

    The development of drugs to combat diseases, chemicals to improve food production, or compounds to enhance the quality of life necessitates, by law, the use of laboratory animals to test their safety. In order to simulate the human condition it is necessary to choose a species in which pharmacokinetic and toxicokinetic mechanisms are established and resemble those of humans. The advantages of the use of the rat in drug and chemical toxicity testing include (a) metabolic pathway similarities to humans; (b) numerous similar anatomical and physiological characteristics; (c) a large database, which is extremely important for comparative purposes; and (d) the ease of breeding and maintenance of animals at relatively low cost. However, the choice of rat can be complicated, especially when over 200 different strains of rat are known to exist. The aim of this review is to summarize genetically determined differences in the responsiveness of rat strains to drugs and naturally occurring chemicals and to show that susceptibility is dependent on the target organ sensitivities, which may also be strain dependent. It is suggested that detailed studies of strain differences may help to clarify toxic mechanisms. Such studies are usually best conducted using inbred strains in which the genetic characteristics have been fixed, rather than in outbred stocks in which individual samples of animals may differ, the phenotype is variable, and the stocks are subject to substantial genetic drift. The fact that strains may differ also needs to be taken into account in assessing the potential hazard of the chemical, particularly when a study involves only a single strain and therefore provides no assessment of likely strain variation.

  20. FishMORPH - An agent-based model to predict salmonid growth and distribution responses under natural and low flows.

    PubMed

    Phang, S C; Stillman, R A; Cucherousset, J; Britton, J R; Roberts, D; Beaumont, W R C; Gozlan, R E

    2016-01-01

    Predicting fish responses to modified flow regimes is becoming central to fisheries management. In this study we present an agent-based model (ABM) to predict the growth and distribution of young-of-the-year (YOY) and one-year-old (1+) Atlantic salmon and brown trout in response to flow change during summer. A field study of a real population during both natural and low flow conditions provided the simulation environment and validation patterns. Virtual fish were realistic both in terms of bioenergetics and feeding. We tested alternative movement rules to replicate observed patterns of body mass, growth rates, stretch distribution and patch occupancy patterns. Notably, there was no calibration of the model. Virtual fish prioritising consumption rates before predator avoidance replicated observed growth and distribution patterns better than a purely maximising consumption rule. Stream conditions of low predation and harsh winters provide ecological justification for the selection of this behaviour during summer months. Overall, the model was able to predict distribution and growth patterns well across both natural and low flow regimes. The model can be used to support management of salmonids by predicting population responses to predicted flow impacts and associated habitat change. PMID:27431787

  1. FishMORPH - An agent-based model to predict salmonid growth and distribution responses under natural and low flows

    PubMed Central

    Phang, S. C.; Stillman, R. A.; Cucherousset, J.; Britton, J. R.; Roberts, D.; Beaumont, W. R. C.; Gozlan, R. E.

    2016-01-01

    Predicting fish responses to modified flow regimes is becoming central to fisheries management. In this study we present an agent-based model (ABM) to predict the growth and distribution of young-of-the-year (YOY) and one-year-old (1+) Atlantic salmon and brown trout in response to flow change during summer. A field study of a real population during both natural and low flow conditions provided the simulation environment and validation patterns. Virtual fish were realistic both in terms of bioenergetics and feeding. We tested alternative movement rules to replicate observed patterns of body mass, growth rates, stretch distribution and patch occupancy patterns. Notably, there was no calibration of the model. Virtual fish prioritising consumption rates before predator avoidance replicated observed growth and distribution patterns better than a purely maximising consumption rule. Stream conditions of low predation and harsh winters provide ecological justification for the selection of this behaviour during summer months. Overall, the model was able to predict distribution and growth patterns well across both natural and low flow regimes. The model can be used to support management of salmonids by predicting population responses to predicted flow impacts and associated habitat change. PMID:27431787

  2. Impact of dexamethasone, etoposide, ifosfamide and carboplatin as concurrent chemoradiotherapy agents for nasal natural killer/T-cell lymphoma.

    PubMed

    Hatayama, Yoshiomi; Aoki, Masahiko; Kawaguchi, Hideo; Narita, Yuichiro; Hirose, Katsumi; Sato, Mariko; Takai, Yoshihiro

    2013-07-01

    The nasal type of extranodal natural killer (NK)/T-cell lymphoma (NKTCL) is a rare aggressive lymphoma with poor prognosis. The reported 5-year overall survival for patients with localized nasal NKTCL treated with cyclophosphamide, hydroxydaunorubicin, oncovin and prednisone (CHOP) is <50%. Dexamethasone, etoposide, ifosfamide and carboplatin (DeVIC) chemotherapy was designed as a salvage chemotherapeutic regimen for aggressive lymphoma, comprising multidrug resistance (MDR) non-related agents and etoposide, which is considered to be effective against nasal NKTCL. An experimental chemoradiotherapy (CRT) is currently being designed using DeVIC as the concurrent chemotherapeutic regimen for nasal NKTCL. The aim of this study was to examine the initial outcome of this treatment and evaluate its effectiveness and feasibility. Six patients (age range, 29-82 years; median age, 68 years) were treated with CRT using DeVIC between April, 2004 and February, 2010. The median follow-up was 56 months (range, 11-80 months). All patients were administered 3-6 cycles of full-dose DeVIC regimen. The chemotherapy was administered concurrently with radiotherapy (RT) and was repeated every 3 weeks. RT was performed using 4-MV X-ray and the prescription dose was 46-50 Gy/23-25 fx (median, 50 Gy). After treatment, all patients were followed up at our hospital. A complete remission was achieved in 5 patients (83%) at 1 month after treatment. The 5-year overall survival and disease-free survival rates were 100%. No severe adverse effect (grade ≥3) was reported. In conclusion, the initial results of the experimental CRT with DeVIC for this type of aggressive lymphoma were very encouraging. Further investigation is required on concurrent CRT with 50 Gy/25 fx and 3 cycles of DeVIC comprising non-MDR agents and etoposide for nasal NKTCL. PMID:24649228

  3. Understanding coupled natural and human systems on fire prone landscapes: integrating wildfire simulation into an agent based planning system.

    NASA Astrophysics Data System (ADS)

    Barros, Ana; Ager, Alan; Preisler, Haiganoush; Day, Michelle; Spies, Tom; Bolte, John

    2015-04-01

    Agent-based models (ABM) allow users to examine the long-term effects of agent decisions in complex systems where multiple agents and processes interact. This framework has potential application to study the dynamics of coupled natural and human systems where multiple stimuli determine trajectories over both space and time. We used Envision, a landscape based ABM, to analyze long-term wildfire dynamics in a heterogeneous, multi-owner landscape in Oregon, USA. Landscape dynamics are affected by land management policies, actors decisions, and autonomous processes such as vegetation succession, wildfire, or at a broader scale, climate change. Key questions include: 1) How are landscape dynamics influenced by policies and institutions, and 2) How do land management policies and actor decisions interact to produce intended and unintended consequences with respect to wildfire on fire-prone landscapes. Applying Envision to address these questions required the development of a wildfire module that could accurately simulate wildfires on the heterogeneous landscapes within the study area in terms of replicating historical fire size distribution, spatial distribution and fire intensity. In this paper we describe the development and testing of a mechanistic fire simulation system within Envision and application of the model on a 3.2 million fire prone landscape in central Oregon USA. The core fire spread equations use the Minimum Travel Time algorithm developed by M Finney. The model operates on a daily time step and uses a fire prediction system based on the relationship between energy release component and historical fires. Specifically, daily wildfire probabilities and sizes are generated from statistical analyses of historical fires in relation to daily ERC values. The MTT was coupled with the vegetation dynamics module in Envision to allow communication between the respective subsystem and effectively model fire effects and vegetation dynamics after a wildfire. Canopy and

  4. Impact of natural control agents of the citrus leafminer Phyllocnistis citrella on lemon trees varies among seasons.

    PubMed

    Goane, L; Casmuz, A; Salas, H; Willink, E; Mangeaud, A; Valladares, G

    2015-12-01

    Studies on insect natural enemies and their effects on host populations are of immense practical value in pest management. Predation and parasitism on a citrus pest, the leafminer Phyllocnistis citrella Stainton, were evaluated by sampling over 3 years in four locations within a world leading lemon producing area in Northwest Argentina. Both mortality factors showed seasonal trends consistent across locations, with predation exerting earlier and more sustained pressure than parasitism, which showed wider seasonal variations. The dominant parasitoids, native Cirrospilus neotropicus and introduced Ageniaspis citricola, showed different seasonal trends: C. neotropicus was dominant in spring whereas A. citricola superseded it in autumn and winter. Although parasitism rates were relatively low, the native C. neotropicus revealed favourable features as potential control agent, by showing density-dependence, parasitism rates comparable with those of the specific A. citricola during part of the cycle, and earlier synchronization with the host. The study provides highly relevant information for a sustainable management of this worldwide pest, for which biological control is considered the best long-term option. PMID:26344662

  5. Impact of natural control agents of the citrus leafminer Phyllocnistis citrella on lemon trees varies among seasons.

    PubMed

    Goane, L; Casmuz, A; Salas, H; Willink, E; Mangeaud, A; Valladares, G

    2015-12-01

    Studies on insect natural enemies and their effects on host populations are of immense practical value in pest management. Predation and parasitism on a citrus pest, the leafminer Phyllocnistis citrella Stainton, were evaluated by sampling over 3 years in four locations within a world leading lemon producing area in Northwest Argentina. Both mortality factors showed seasonal trends consistent across locations, with predation exerting earlier and more sustained pressure than parasitism, which showed wider seasonal variations. The dominant parasitoids, native Cirrospilus neotropicus and introduced Ageniaspis citricola, showed different seasonal trends: C. neotropicus was dominant in spring whereas A. citricola superseded it in autumn and winter. Although parasitism rates were relatively low, the native C. neotropicus revealed favourable features as potential control agent, by showing density-dependence, parasitism rates comparable with those of the specific A. citricola during part of the cycle, and earlier synchronization with the host. The study provides highly relevant information for a sustainable management of this worldwide pest, for which biological control is considered the best long-term option.

  6. Serologic evidence of a natural infection of white-tailed deer with the agent of human granulocytic ehrlichiosis in Wisconsin and Maryland.

    PubMed

    Walls, J J; Asanovich, K M; Bakken, J S; Dumler, J S

    1998-11-01

    White-tailed deer participate in the maintenance of the Ixodes tick life cycle and are reservoirs for some tick-borne infectious agents. Deer may be useful sentinels for tick-transmitted agents, such as ehrlichiae. In order to determine whether white-tailed deer are markers of natural transmission or are reservoirs for the human granulocytic ehrlichiosis (HGE) agent, we performed indirect immunofluorescent-antibody (IFA) tests and immunoblotting with the HGE agent and Ehrlichia chaffeensis on sera from 43 and 294 deer captured in northwest Wisconsin during 1994 and 1995, respectively, and 12 deer from southern Maryland. According to IFA testing, 47% of 1994 Wisconsin sera, 60% of 1995 Wisconsin sera, and 25% of Maryland sera contained HGE agent antibodies. All IFA-positive deer sera tested reacted with the 44-kDa band which is unique to the Ehrlichia phagocytophila group. Serologic reactions to E. chaffeensis were detected by IFA testing in 15 of 337 (4%) Wisconsin deer and in 10 of 12 (83%) Maryland deer, while 60 and 80% of E. chaffeensis IFA-positive Wisconsin and Maryland deer sera, respectively, reacted with the E. chaffeensis 28- to 29-kDa antigens by immunoblotting. A total of 4% of deer from Wisconsin and 25% of deer from Maryland were found by IFA testing to have antibodies to both the HGE agent and E. chaffeensis; 75% of these were confirmed to contain E. chaffeensis antibodies by immunoblotting. These results suggest that white-tailed deer in diverse geographical regions of the United States are naturally infected with the HGE agent, E. chaffeensis, or both and that these animals, and potentially humans, are exposed to infected ticks at a high frequency in nature. PMID:9801331

  7. Natural Products as Anti-HIV Agents and Role in HIV-Associated Neurocognitive Disorders (HAND): A Brief Overview.

    PubMed

    Kurapati, Kesava Rao V; Atluri, Venkata S; Samikkannu, Thangavel; Garcia, Gabriella; Nair, Madhavan P N

    2015-01-01

    As the threat of Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) persists to rise, effective drug treatments are required to treat the infected people. Even though combination antiretroviral therapy (cART) provides stable viral suppression, it is not devoid of undesirable side effects, especially in persons undergoing long-term treatment. The present therapy finds its limitations in the emergence of multidrug resistance and accordingly finding new drugs and novel targets is the need of the hour to treat the infected persons and further to attack HIV reservoirs in the body like brain, lymph nodes to achieve the ultimate goal of complete eradication of HIV and AIDS. Natural products such as plant-originated compounds and plant extracts have enormous potential to become drug leads with anti-HIV and neuroprotective activity. Accordingly, many research groups are exploring the biodiversity of the plant kingdom to find new and better anti-HIV drugs with novel mechanisms of action and for HIV-associated neurocognitive disorders (HAND). The basic challenge that still persists is to develop viral replication-targeted therapy using novel anti-HIV compounds with new mode of action, accepted toxicity and less resistance profile. Against this backdrop, the World Health Organization (WHO) suggested the need to evaluate ethno-medicines for the management of HIV/AIDS. Consequently, there is need to evaluate traditional medicine, particularly medicinal plants and other natural products that may yield effective and affordable therapeutic agents. Although there are a good number of reports on traditional uses of plants to treat various diseases, knowledge of herbal remedies used to manage HIV/AIDS and HAND are scanty, vague and not well documented. In this review, plant substances showing a promising action that is anti-HIV and HAND will be explored along with what they interact. Since some plant substances are also known to modulate several cellular

  8. Natural Products as Anti-HIV Agents and Role in HIV-Associated Neurocognitive Disorders (HAND): A Brief Overview

    PubMed Central

    Kurapati, Kesava Rao V.; Atluri, Venkata S.; Samikkannu, Thangavel; Garcia, Gabriella; Nair, Madhavan P. N.

    2016-01-01

    As the threat of Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) persists to rise, effective drug treatments are required to treat the infected people. Even though combination antiretroviral therapy (cART) provides stable viral suppression, it is not devoid of undesirable side effects, especially in persons undergoing long-term treatment. The present therapy finds its limitations in the emergence of multidrug resistance and accordingly finding new drugs and novel targets is the need of the hour to treat the infected persons and further to attack HIV reservoirs in the body like brain, lymph nodes to achieve the ultimate goal of complete eradication of HIV and AIDS. Natural products such as plant-originated compounds and plant extracts have enormous potential to become drug leads with anti-HIV and neuroprotective activity. Accordingly, many research groups are exploring the biodiversity of the plant kingdom to find new and better anti-HIV drugs with novel mechanisms of action and for HIV-associated neurocognitive disorders (HAND). The basic challenge that still persists is to develop viral replication-targeted therapy using novel anti-HIV compounds with new mode of action, accepted toxicity and less resistance profile. Against this backdrop, the World Health Organization (WHO) suggested the need to evaluate ethno-medicines for the management of HIV/AIDS. Consequently, there is need to evaluate traditional medicine, particularly medicinal plants and other natural products that may yield effective and affordable therapeutic agents. Although there are a good number of reports on traditional uses of plants to treat various diseases, knowledge of herbal remedies used to manage HIV/AIDS and HAND are scanty, vague and not well documented. In this review, plant substances showing a promising action that is anti-HIV and HAND will be explored along with what they interact. Since some plant substances are also known to modulate several cellular

  9. The effect of nitrate, bicarbonate and natural organic matter on the degradation of sunscreen agent p-aminobenzoic acid by simulated solar irradiation.

    PubMed

    Mao, Liang; Meng, Cui; Zeng, Chao; Ji, Yuefei; Yang, Xi; Gao, Shixiang

    2011-11-15

    Our experiments revealed that a model sunscreen agent, p-aminobenzoic acid (PABA), can be effectively transformed through reactions that are mediated by simulated solar irradiation. We systematically explored the effects of nitrate ions, bicarbonate and different types of natural organic matter (NOM) on the degradation of PABA by simulated solar irradiation. Experimental data suggest that these components ubiquitous in nature water have different influence on the rates of the photoinduced removal of PABA. Products were extracted and analyzed using LC/MS and a total of four products probably resulting from OH and NO2 radicals attack were identified and the possible reaction pathways were proposed. The findings in this study provide useful information for understanding the environmental transformation of sunscreen agent in aquatic system. PMID:21975008

  10. Analysis of the effect of a sunscreen agent on the suppression of natural killer cell activity induced in human subjects by radiation from solarium lamps

    SciTech Connect

    Hersey, P.; MacDonald, M.; Burns, C.; Schibeci, S.; Matthews, H.; Wilkinson, F.J.

    1987-03-01

    Previous studies in rodents have shown that ultraviolet radiation (UVR) may have direct effects on the immune system in the skin and at higher doses may induce systemic suppression of immune responses. We have previously shown that UVR from sun or solarium beds may induce systemic effects in human subjects. The purpose of the present study was to examine whether these systemic effects in human subjects could be prevented by use of commercially available sunscreen agents. Groups of 12 normal subjects were exposed to radiation from solarium lamps after application of a sunscreen agent or the base used in its preparation. Twelve half-hourly exposures induced a depression of natural killer (NK) cell activity against a melanoma and the K562 target cell which was not prevented by use of the sunscreen agent. Changes in functional activity were accompanied by a reduction in NK cell numbers assessed by Leu-11 monoclonal antibodies against the labile Fc receptor. Application of the sunscreen agent also did not protect against effects of solarium exposure on recall antigen skin tests and immunoglobulin production in vitro in pokeweed mitogen-stimulated cultures of B and T cells. These results suggest that further evaluation of the wave-length spectrum of UVR and the effectiveness of sunscreen agents in prevention of UVR-induced effects on the immune system is needed.

  11. Partnerships for Natural Resource Education: Differing Program Needs and Perspectives of Extension Agents and State Agency Staff.

    ERIC Educational Resources Information Center

    Monroe, Martha C.; Jacobson, Susan K.; Bowers, Alison

    2003-01-01

    A survey of 45 extension agents and 59 state forestry agency staff 1 year after inservice training on developing public education programs on wildland fire received 71 responses. Three primary barriers to program implementation were identified: educational, logistical, and attitudinal. Providing a toolkit of materials and resources reduced…

  12. In Vitro and In Vivo Studies of Non-Platinum-Based Halogenated Compounds as Potent Antitumor Agents for Natural Targeted Chemotherapy of Cancers.

    PubMed

    Lu, Qing-Bin; Zhang, Qin-Rong; Ou, Ning; Wang, Chun-Rong; Warrington, Jenny

    2015-06-01

    Based on a molecular-mechanism-based anticancer drug discovery program enabled by an innovative femtomedicine approach, we have found a previously unknown class of non-platinum-based halogenated molecules (called FMD compounds) as potent antitumor agents for effective treatment of cancers. Here, we present in vitro and in vivo studies of the compounds for targeted chemotherapy of cervical, breast, ovarian, and lung cancers. Our results show that these FMD agents led to DNA damage, cell cycle arrest in the S phase, and apoptosis in cancer cells. We also observed that such a FMD compound caused an increase of reduced glutathione (GSH, an endogenous antioxidant) levels in human normal cells, while it largely depleted GSH in cancer cells. We correspondingly found that these FMD agents exhibited no or little toxicity toward normal cells/tissues, while causing significant cytotoxicity against cancer cells, as well as suppression and delay in tumor growth in mouse xenograft models of cervical, ovarian, breast and lung cancers. These compounds are therefore a previously undiscovered class of potent antitumor agents that can be translated into clinical trials for natural targeted chemotherapy of multiple cancers.

  13. In Vitro and In Vivo Studies of Non-Platinum-Based Halogenated Compounds as Potent Antitumor Agents for Natural Targeted Chemotherapy of Cancers

    PubMed Central

    Lu, Qing-Bin; Zhang, Qin-Rong; Ou, Ning; Wang, Chun-Rong; Warrington, Jenny

    2015-01-01

    Based on a molecular-mechanism-based anticancer drug discovery program enabled by an innovative femtomedicine approach, we have found a previously unknown class of non-platinum-based halogenated molecules (called FMD compounds) as potent antitumor agents for effective treatment of cancers. Here, we present in vitro and in vivo studies of the compounds for targeted chemotherapy of cervical, breast, ovarian, and lung cancers. Our results show that these FMD agents led to DNA damage, cell cycle arrest in the S phase, and apoptosis in cancer cells. We also observed that such a FMD compound caused an increase of reduced glutathione (GSH, an endogenous antioxidant) levels in human normal cells, while it largely depleted GSH in cancer cells. We correspondingly found that these FMD agents exhibited no or little toxicity toward normal cells/tissues, while causing significant cytotoxicity against cancer cells, as well as suppression and delay in tumor growth in mouse xenograft models of cervical, ovarian, breast and lung cancers. These compounds are therefore a previously undiscovered class of potent antitumor agents that can be translated into clinical trials for natural targeted chemotherapy of multiple cancers. PMID:26351651

  14. Purines, prostaglandins and peptides--nature and cellular mechanisms of action of local assist and assassin agents in the ovary.

    PubMed

    Behrman, H R; Aten, R F; Luborsky, J L; Polan, M L; Miller, J G; Soodak, L K

    1986-01-01

    The evidence for a paracrine, progonadotropic role of adenosine in ovarian cells is summarized along with a capsule review of the origin and mechanisms of release and action of adenosine in other tissues. Briefly, adenosine markedly amplified rat and human luteal cell cyclic AMP and progesterone accumulation in the presence, but not the absence, of LH. The site of action of adenosine was found to be intracellular, linked to its phosphorylation, which resulted in increased levels of ATP. In rat luteal cells, adenosine blocked the acute antigonadotropic (luteolytic) action of PGF2 alpha. In the follicle, adenosine release from granulosal cells appeared to be stimulated by FSH. Adenosine and a nonmetabolized adenosine analog, augmented FSH-dependent inhibition of oocyte maturation in the presence or absence of an adenosine transport inhibitor. Inhibition of oocyte maturation by adenosine thus appears to be mediated by extracellular purinergic receptors. Paracrine, antigonadotropic agents also appear to regulate ovarian function. For example, GnRH elicits antigonadotropic activity in rat granulosal and luteal cells. We describe a novel, GnRH-like, ovarian hormone (GLOH) which may be the physiological ligand whose action GnRH mimics in rat ovarian cells. This protein was shown to be distinctly different from GnRH and a variety of other cyclic and noncyclic peptides. PGF2 alpha is a well known leutolytic agent and a summary of the antigonadotropic mechanism of PGF2 alpha action in rat luteal cells is presented. In these cells, the action of GnRH (or possibly the GnRH-like protein) and PGF2 alpha are mediated by separate membrane receptors but they appeared to share the same intracellular second messenger. Evidence for a role of products of phosphoinositol as a mediator of these antigonadotropic agents is summarized. We suggest that the ultimate mediator of antigonadotropic agents is Ca2+ which is released in the luteal cell in response to the intracellular mediator of

  15. Nonsteroidal anti-inflammatory drug activated gene-1 (NAG-1) modulators from natural products as anti-cancer agents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural products are rich source of gene modulators for prevention and treatment of cancer. In recent days, nonsteroidal anti-inflammatory drug (NSAID) activated gene-1 (NAG-1) has been focused as a new target of diverse cancers like colorectal, pancreatic, prostate, and breast. A variety of natural...

  16. Marine and soil derived natural products: a new source of novel cardiovascular protective agents targeting the endothelin system.

    PubMed

    Planes, Nadir; Caballero-George, Catherina

    2015-06-01

    Inhibition of the endothelin system is a recognized therapeutic approach for treating complex cardiovascular diseases. The search for natural inhibitors of the endothelin system has focused mainly on land, with recent, emerging data suggesting the underestimated potential of marine microorganisms for producing leads with cardioprotective potential. The present work reviews natural products identified as inhibitors of the endothelin system, their origin, their mechanism of action, and their ecological significance.

  17. Molecular analysis of faecal samples from birds to identify potential crop pests and useful biocontrol agents in natural areas.

    PubMed

    King, R A; Symondson, W O C; Thomas, R J

    2015-06-01

    Wild habitats adjoining farmland are potentially valuable sources of natural enemies, but also of pests. Here we tested the utility of birds as 'sampling devices', to identify the diversity of prey available to predators and particularly to screen for pests and natural enemies using natural ecosystems as refugia. Here we used PCR to amplify prey DNA from three sympatric songbirds foraging on small invertebrates in Phragmites reedbed ecosystems, namely the Reed Warbler (Acrocephalus scirpaceus), Sedge Warbler (Acrocephalus schoenobaenus) and Cetti's Warbler (Cettia cetti). A recently described general invertebrate primer pair was used for the first time to analyse diets. Amplicons were cloned and sequenced, then identified by reference to the Barcoding of Life Database and to our own sequences obtained from fresh invertebrates. Forty-five distinct prey DNA sequences were obtained from 11 faecal samples, of which 39 could be identified to species or genus. Targeting three warbler species ensured that species-specific differences in prey choice broadened the range of prey taken. Amongst the prey found in reedbeds were major pests (including the tomato moth Lacanobia oleracea) as well as many potentially valuable natural enemies including aphidophagous hoverflies and braconid wasps. Given the mobility of birds, this approach provides a practical way of sampling a whole habitat at once, providing growers with information on possible invasion by locally resident pests and the colonization potential of natural enemies from local natural habitats. PMID:25572526

  18. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

    PubMed Central

    Wirth, Marius; Niro, Giuliana; Leyerer, Kristin

    2016-01-01

    Summary Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY), a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR) studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field. PMID:27340469

  19. [Repellent activity against Aedes aegypti (L.) of formulas based on natural vegetable extracts or synthetic active agents].

    PubMed

    Girgenti, P; Suss, L

    2002-01-01

    A comparison of 5 commercial mosquito repellents was made on adult male and female volunteers in laboratory trials. The products tested in forms of cream or lotion included 4 natural oil formulations (containing citronella, clover, eucalyptus, geranium, lavender, peppermint, sandalwood, thyme, etc.) and 1 synthetic chemical repellent containing 10% KBR 3023). Natural oil products showed essentially poor or no repellency against Ae, aegypti: the protection times were less than or equal to 1 hour. Only the synthetic repellent based on KBR 3023 provided satisfactory defence to human volunteers. PMID:12162118

  20. [Repellent activity against Aedes aegypti (L.) of formulas based on natural vegetable extracts or synthetic active agents].

    PubMed

    Girgenti, P; Suss, L

    2002-01-01

    A comparison of 5 commercial mosquito repellents was made on adult male and female volunteers in laboratory trials. The products tested in forms of cream or lotion included 4 natural oil formulations (containing citronella, clover, eucalyptus, geranium, lavender, peppermint, sandalwood, thyme, etc.) and 1 synthetic chemical repellent containing 10% KBR 3023). Natural oil products showed essentially poor or no repellency against Ae, aegypti: the protection times were less than or equal to 1 hour. Only the synthetic repellent based on KBR 3023 provided satisfactory defence to human volunteers.

  1. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents.

    PubMed

    Wiegmann, Daniel; Koppermann, Stefan; Wirth, Marius; Niro, Giuliana; Leyerer, Kristin; Ducho, Christian

    2016-01-01

    Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY), a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure-activity relationship (SAR) studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field. PMID:27340469

  2. Nature's Chiral Catalyst and Anti-Malarial Agent: Isolation and Structure Elucidation of Cinchonine and Quinine from "Cinchona calisaya"

    ERIC Educational Resources Information Center

    Carroll, Anne-Marie; Kavanagh, David J.; McGovern, Fiona P.; Reilly, Joe W.; Walsh, John J.

    2012-01-01

    Nature is a well-recognized source of compounds of interest, but access is often an issue. One pertinent example is the cinchona alkaloids from the bark of "Cinchona calisaya." In this experiment, students at the third-year undergraduate level undertake the selective isolation and characterization of two of the four main alkaloids present in the…

  3. Physa marmorata (Mollusca: Physidae) as a natural intermediate host of Trichobilharzia (Trematoda: Schistosomatidae), a potential causative agent of avian cercarial dermatitis in Brazil.

    PubMed

    Pinto, Hudson A; Brant, Sara V; de Melo, Alan L

    2014-10-01

    Species of Trichobilharzia are the main etiological agents of cercarial dermatitis in humans, which is considered a re-emerging disease. Despite the diversity and global distribution of species of this genus, studies of Trichobilharzia are scarce in South America. The goal of our investigations is better understand the diversity, distribution and life cycle of avian schistosomes and their likely role in causing dermatitis in Brazil. As part of this effort, cercariae found in naturally infected Physa marmorata were identified by morphological and molecular (mitochondrial cox1, nuclear ITS1 and 28S gene regions) methods as Trichobilharzia sp. These cercariae are similar morphologically to T. jequitibaensis described previously from Brazil and similar genetically to the North American physid transmitted species T. querquedulae and T. physellae. This is the first report of a potential agent of cercarial dermatitis from naturally infected snails from Brazil and first molecular characterization of a South American species of Trichobilharzia. A discussion follows concerning the potential role of this species has in outbreaks of dermatitis in Brazil.

  4. The contagious nature of imprisonment: an agent-based model to explain racial disparities in incarceration rates

    PubMed Central

    Lum, Kristian; Swarup, Samarth; Eubank, Stephen; Hawdon, James

    2014-01-01

    We build an agent-based model of incarceration based on the susceptible–infected–suspectible (SIS) model of infectious disease propagation. Our central hypothesis is that the observed racial disparities in incarceration rates between Black and White Americans can be explained as the result of differential sentencing between the two demographic groups. We demonstrate that if incarceration can be spread through a social influence network, then even relatively small differences in sentencing can result in large disparities in incarceration rates. Controlling for effects of transmissibility, susceptibility and influence network structure, our model reproduces the observed large disparities in incarceration rates given the differences in sentence lengths for White and Black drug offenders in the USA without extensive parameter tuning. We further establish the suitability of the SIS model as applied to incarceration by demonstrating that the observed structural patterns of recidivism are an emergent property of the model. In fact, our model shows a remarkably close correspondence with California incarceration data. This work advances efforts to combine the theories and methods of epidemiology and criminology. PMID:24966237

  5. The contagious nature of imprisonment: an agent-based model to explain racial disparities in incarceration rates.

    PubMed

    Lum, Kristian; Swarup, Samarth; Eubank, Stephen; Hawdon, James

    2014-09-01

    We build an agent-based model of incarceration based on the susceptible-infected-suspectible (SIS) model of infectious disease propagation. Our central hypothesis is that the observed racial disparities in incarceration rates between Black and White Americans can be explained as the result of differential sentencing between the two demographic groups. We demonstrate that if incarceration can be spread through a social influence network, then even relatively small differences in sentencing can result in large disparities in incarceration rates. Controlling for effects of transmissibility, susceptibility and influence network structure, our model reproduces the observed large disparities in incarceration rates given the differences in sentence lengths for White and Black drug offenders in the USA without extensive parameter tuning. We further establish the suitability of the SIS model as applied to incarceration by demonstrating that the observed structural patterns of recidivism are an emergent property of the model. In fact, our model shows a remarkably close correspondence with California incarceration data. This work advances efforts to combine the theories and methods of epidemiology and criminology.

  6. Melatonin, a potent agent in antioxidative defense: Actions as a natural food constituent, gastrointestinal factor, drug and prodrug

    PubMed Central

    Hardeland, Rüdiger; Pandi-Perumal, SR

    2005-01-01

    Melatonin, originally discovered as a hormone of the pineal gland, is also produced in other organs and represents, additionally, a normal food constituent found in yeast and plant material, which can influence the level in the circulation. Compared to the pineal, the gastrointestinal tract contains several hundred times more melatonin, which can be released into the blood in response to food intake and stimuli by nutrients, especially tryptophan. Apart from its use as a commercial food additive, supraphysiological doses have been applied in medical trials and pure preparations are well tolerated by patients. Owing to its amphiphilicity, melatonin can enter any body fluid, cell or cell compartment. Its properties as an antioxidant agent are based on several, highly diverse effects. Apart from direct radical scavenging, it plays a role in upregulation of antioxidant and downregulation of prooxidant enzymes, and damage by free radicals can be reduced by its antiexcitatory actions, and presumably by contributions to appropriate internal circadian phasing, and by its improvement of mitochondrial metabolism, in terms of avoiding electron leakage and enhancing complex I and complex IV activities. Melatonin was shown to potentiate effects of other antioxidants, such as ascorbate and Trolox. Under physiological conditions, direct radical scavenging may only contribute to a minor extent to overall radical detoxification, although melatonin can eliminate several of them in scavenger cascades and potentiates the efficacy of antioxidant vitamins. Melatonin oxidation seems rather important for the production of other biologically active metabolites such as N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK) and N1-acetyl-5-methoxykynuramine (AMK), which have been shown to also dispose of protective properties. Thus, melatonin may be regarded as a prodrug, too. AMK interacts with reactive oxygen and nitrogen species, conveys protection to mitochondria, inhibits and downregulates

  7. Honokiol: a promising small molecular weight natural agent for the growth inhibition of oral squamous cell carcinoma cells.

    PubMed

    Chen, Xi-Rui; Lu, Rui; Dan, Hong-Xia; Liao, Ga; Zhou, Min; Li, Xiao-Yu; Ji, Ning

    2011-01-01

    Honokiol (HNK) is a small organic molecule purified from magnolia species and has demonstrated anticancer activities in a variety of cancer cell lines; however, its effect on oral squamous cell carcinoma (OSCC) cells is unknown. We investigated the antitumor activities of HNK on OSCC cells in vitro for the first time. The inhibitory effects of HNK on the growth and proliferation of OSCC cells were demonstrated via in vitro 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and propidium iodide (PI) assays, and the apoptotic cells were investigated by the observation of morphological changes and detection of DNA fragmentation via PI, TdT-mediated dUTP-biotin nick end labeling (TUNEL), and DNA ladder assays, as well as flow cytometry assay. The results showed that HNK inhibited the growth and proliferation of OSCC cells in vitro in a time and dose-dependent manner. The inhibitory effect was associated with the cell apoptosis induced by HNK, evidenced by the morphological features of apoptotic cells, TUNEL-positive cells and a degradation of chromosomal DNA into small internucleosomal fragments. The study also demonstrated here that the inhibition or apoptosis mediated by 15 microg x mL(-1) or 20 microg x mL(-1) of HNK were more stronger compared with those of 20 microg x mL(-1) 5-fluorouracil (5-Fu, the control) applied to OSCC cells, when the ratio of OSCC cell numbers were measured between the treatment of different concentrations of HNK to the 5-Fu treatment for 48 h. HNK is a promising compound that can be potentially used as a novel treatment agent for human OSCC. PMID:21449214

  8. Artificial biomembranes stabilized over spin coated hydrogel scaffolds. Crosslinking agent nature induces wrinkled or flat surfaces on the hydrogel.

    PubMed

    González-Henríquez, C M; Pizarro-Guerra, G C; Córdova-Alarcón, E N; Sarabia-Vallejos, M A; Terraza-Inostroza, C A

    2016-03-01

    Hydrogel films possess the ability of retain water and deliver it to a phospholipid bilayer mainly composed by DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine); moisture of the medium favors the stability of an artificial biomembrane when it is subjected to repetitive heating cycles. This hypothesis is valid when the hydrogel film, used as scaffold, present a flat surface morphology and a high ability for water releasing. On the other hand, when the sample presents a wrinkle topography (periodic undulations), free lateral molecular movement of the bilayer becomes lower, disfavoring the occurrence of clear phases/phase transitions according to applied temperature. Hydrogel films were prepared using HEMA (hydroxyethylmetacrylate), different crosslinking agents and initiators. This reaction mixture was spread over hydrophilic silicon wafers using spin coating technique. Resultant films were then exposed to UV light favoring polymeric chain crosslinking and interactions between hydrogel and substrate; this process is also known to generate tensile stress mismatch between different hydrogel strata, producing out-of-plane net force that generate ordered undulations or collapsed crystals at surface level. DPPC bilayers were then placed over hydrogel using Langmuir-Blodgett technique. Surface morphology was detected in order to clarify the behavior of these films. Obtained data corroborate DPPC membrane stability making possible to detect phases/phase transitions by ellipsometric methods and Atomic Force Microscopy due to their high hydration level. This system is intended to be used as biosensor through the insertion of transmembrane proteins or peptides that detect minimal variations of some analyte in the environment; artificial biomembrane stability and behavior is fundamental for this purpose.

  9. Synthesis of the catechols of natural and synthetic estrogens by using 2-iodoxybenzoic acid (IBX) as the oxidizing agent.

    PubMed

    Saeed, Muhammad; Zahid, Muhammad; Rogan, Eleanor; Cavalieri, Ercole

    2005-03-01

    A method for the synthesis of 2-hydroxyestrone/estradiol, 4-hydroxyestrone/estradiol, 3'-hydroxydiethylstilbestrol, 3'-hydroxyhexestrol, and 3'-hydroxydienestrol is reported, in which 2-iodoxybenzoic acid (IBX) and the corresponding phenolic estrogen are reacted. Treatment of the natural estrogens, estrone/estradiol, with stoichiometric amounts of IBX in dimethylformamide initially yielded a mixture of estrone/estradiol-2,3- and -3,4-quinones, which were reduced in situ to the corresponding catechols by treatment with a 1 M aqueous solution of ascorbic acid. Chromatographic separation of the reaction products afforded 2- and 4-hydroxyestrone/estradiol in good overall yields (79%). In the case of the synthetic estrogens containing two identical phenolic rings, protection of one ring is a prerequisite for the synthesis of the monocatechol. Thus, diethylstilbestrol and dienestrol were protected at one phenol ring as their methyl ethers. The resulting monophenols were treated with stoichiometric amounts of IBX for 1 h, followed by treatment with 1 M aqueous ascorbic acid to obtain the corresponding catechols in more than 70% yield. Furthermore, the catechol of diethylstilbestrol, protected at one ring, was reduced by catalytic hydrogenation at the C3-C4 double bond to obtain 3'-hydroxyhexestrol in 90% yield. Removal of the protected methoxy groups of the synthetic estrogen catechols was carried out by treatment with a 1 M solution of boron tribromide in dichloromethane. This method is highly efficient for the preparative scale synthesis of catechols of both natural and synthetic estrogens.

  10. Iron speciation in natural waters by sequential injection analysis with a hexadentate 3-hydroxy-4-pyridinone chelator as chromogenic agent.

    PubMed

    Miranda, Joana L A; Mesquita, Raquel B R; Nunes, Ana; Rangel, Maria; Rangel, António O S S

    2016-02-01

    A sequential injection method for iron speciation in various types of natural waters was developed using a synthesised hexadentate 3-hydroxy-4-pyridinone chelator (CP256). The denticity of the ligand that allow formation of the corresponding iron(III) complex in a 1:1 stoichiometry proved to be highly advantageous, in comparison with parent bidentate, hydroxy-4-piridinone chelators, with a two fold increase of reaction sensitivity and over 65% decrease of the LOD. A solid phase extraction approach was employed to attain matrix elimination, facilitating iron(III) determination and application to high salinity waters. The combination with the total iron determination obtained by the direct reaction of the ligand resulted in iron speciation. Two detection spectrophotometric cells were tested, a conventional flow cell (CFC) and a liquid waveguide capillary cell (LWCC). The dynamic concentration ranges were 0.1-2 mg/L with the CFC detection and 0.005-0.1 mg/L with the LWCC, with limit of detection of 30 µg/L and 6 µg/L, respectively. The developed method was successfully applied to a variety of natural waters.

  11. Chestnut and lemon balm based ingredients as natural preserving agents of the nutritional profile in matured "Serra da Estrela" cheese.

    PubMed

    Carocho, Márcio; Barreira, João C M; Bento, Albino; Fernández-Ruiz, Virginia; Morales, Patricia; Ferreira, Isabel C F R

    2016-08-01

    Chestnut flowers, lemon balm plants and their decoctions were incorporated into "Serra da Estrela" cheese, to assess their potential to preserve its nutritional properties and provide new foodstuffs. The analyses were carried out after the normal ripening period of 1month and after 6months of storage. The most abundant nutrients were proteins and fats. The most abundant minerals were Ca and Na, while C16:0 and C18:1 were the main fatty acids. Saturated fatty acids were the most abundant, followed by the monounsaturated. Moisture seemed to be lower in the samples with the plants incorporated. The dried plants, when incorporated, seemed to be more efficient as preservers then the decoctions, although these better preserved the proteins. These plants can be regarded as promising natural preservers in foodstuffs cheese, given the preservation of key parameters and the slight impact on the nutritional value. PMID:26988492

  12. Chestnut and lemon balm based ingredients as natural preserving agents of the nutritional profile in matured "Serra da Estrela" cheese.

    PubMed

    Carocho, Márcio; Barreira, João C M; Bento, Albino; Fernández-Ruiz, Virginia; Morales, Patricia; Ferreira, Isabel C F R

    2016-08-01

    Chestnut flowers, lemon balm plants and their decoctions were incorporated into "Serra da Estrela" cheese, to assess their potential to preserve its nutritional properties and provide new foodstuffs. The analyses were carried out after the normal ripening period of 1month and after 6months of storage. The most abundant nutrients were proteins and fats. The most abundant minerals were Ca and Na, while C16:0 and C18:1 were the main fatty acids. Saturated fatty acids were the most abundant, followed by the monounsaturated. Moisture seemed to be lower in the samples with the plants incorporated. The dried plants, when incorporated, seemed to be more efficient as preservers then the decoctions, although these better preserved the proteins. These plants can be regarded as promising natural preservers in foodstuffs cheese, given the preservation of key parameters and the slight impact on the nutritional value.

  13. Effect of the salting-out agent anion nature on the phase separation of a potassium salt-potassium bis(alkyl polyoxyethylene)phosphate-water systems

    NASA Astrophysics Data System (ADS)

    Elokhov, A. M.; Lesnov, A. E.; Kudryashova, O. S.

    2016-10-01

    The effect the salting-out agent anion nature has on the temperature and concentration intervals of the existence of the separation area is established by analyzing the phase diagrams of pseudoternary KCl (KBr, KI, KNO3, K2SO4, K4P2O7)-potassium bis(alkyl polyoxyethylene)phosphate (oxyphos B)-water systems. It is concluded that the anionic salting-out capability is reduced in the order P2O 7 4- > SO 4 2- > Cl- > Br‒> NO 7 4- > SO 3 - > I-. The thermodynamic parameters of phase separation used to interpret the results are calculated. The observed pattern of a change in the salting-out ability of the investigated salts relative to aqueous solutions of the surfactants is in good agreement with the lyotropic (Hofmeister) series.

  14. Design and synthesis of 3,4-methylenedioxy-6-nitrophenoxyacetylhydrazone derivatives obtained from natural safrole: new lead-agents with analgesic and antipyretic properties.

    PubMed

    Bezerra-Netto, Heleno J C; Lacerda, Daniel I; Miranda, Ana Luisa P; Alves, Hélio M; Barreiro, Eliezer J; Fraga, Carlos A M

    2006-12-01

    In this work, we reported the synthesis and evaluation of the analgesic, anti-inflammatory, and antipyretic properties of new 2-(6-nitro-benzo[1,3]dioxol-5-yloxy)-acetylhydrazone derivatives (3), designed exploring molecular hybridization and isosteric replacement approaches between nimesulide (1) and carbanalogue NAH series (2) developed at LASSBio. Target compounds were synthesized in very good yields exploiting abundant Brazilian natural product safrole (4) as starting material. The evaluation of the antinociceptive properties of this series led us to discover a new potent prototype of analgesic and antipyretic agent, that is, NAH derivative 3c, named LASSBio-891, which showed to be more potent than dipyrone used as standard.

  15. Harnessing the multifunctionality in nature: a bioactive agent release system with self-antimicrobial and immunomodulatory properties.

    PubMed

    Özçelik, Hayriye; Vrana, Nihal Engin; Gudima, Alexandru; Riabov, Vladimir; Gratchev, Alexei; Haikel, Youssef; Metz-Boutigue, Marie-Hélène; Carradò, Adele; Faerber, Jacques; Roland, Thierry; Klüter, Harald; Kzhyshkowska, Julia; Schaaf, Pierre; Lavalle, Philippe

    2015-09-16

    Major problems with biomedical devices in particular implants located in nonsterile environments concern: (i) excessive immune response to the implant, (ii) development of bacterial biofilms, and (iii) yeast and fungi infections. An original multifunctional coating that addresses all these issues concomitantly is developed. A new exponentially growing polyelectrolyte multilayer film based on polyarginine (PAR) and hyaluronic acid (HA) is designed. The films have a strong inhibitory effect on the production of inflammatory cytokines released by human primary macrophage subpopulations. This could reduce potential chronic inflammatory reaction following implantation. Next, it is shown that PAR, due to its positive charges, has an antimicrobial activity in film format against Staphylococcus aureus for 24 h. In order to have a long-term antimicrobial activity, a precursor nanoscale silver coating is deposited on the surface before adding the PAR/HA films. Moreover, the PAR/HA films can be easily further functionalized by embedding antimicrobial peptides, like catestatin (CAT), a natural host defense peptide. This PAR/HA+CAT film proves to be effective as an antimicrobial coating against yeast and fungi and its cytocompatibility is also assessed. Finally, this all-in-one system constitutes an original strategy to limit inflammation and prevents bacteria, yeast, and fungi infections. PMID:26379222

  16. Exploring the use of natural antimicrobial agents and pulsed electric fields to control spoilage bacteria during a beer production process.

    PubMed

    Galvagno, M A; Gil, G R; Iannone, L J; Cerrutti, P

    2007-01-01

    Different natural antimicrobials affected viability of bacterial contaminants isolated at critical steps during a beer production process. In the presence of 1 mg/ml chitosan and 0.3 mg/ml hops, the viability of Escherichia coli in an all malt barley extract wort could be reduced to 0.7 and 0.1% respectively after 2 hour- incubation at 4 degrees C. The addition of 0.0002 mg/ml nisin, 0.1 mg/ml chitosan or 0.3 mg/ml hops, selectively inhibited growth of Pediococcus sp. in more than 10,000 times with respect to brewing yeast in a mixed culture. In the presence of 0.1 mg ml chitosan in beer, no viable cells of the thermoresistant strain Bacillus megaterium were detected. Nisin, chitosan and hops increased microbiological stability during storage of a local commercial beer inoculated with Lactobacillus plantarum or Pediococcus sp. isolated from wort. Pulsed Electric Field (PEF) (8 kV/cm, 3 pulses) application enhanced antibacterial activity of nisin and hops but not that of chitosan. The results herein obtained suggest that the use of these antimicrobial compounds in isolation or in combination with PEF would be effective to control bacterial contamination during beer production and storage. PMID:17987854

  17. A Collective Case Study of Secondary Students' Model-Based Inquiry on Natural Selection through Programming in an Agent-Based Modeling Environment

    NASA Astrophysics Data System (ADS)

    Xiang, Lin

    This is a collective case study seeking to develop detailed descriptions of how programming an agent-based simulation influences a group of 8 th grade students' model-based inquiry (MBI) by examining students' agent-based programmable modeling (ABPM) processes and the learning outcomes. The context of the present study was a biology unit on natural selection implemented in a charter school of a major California city during spring semester of 2009. Eight 8th grade students, two boys and six girls, participated in this study. All of them were low socioeconomic status (SES). English was a second language for all of them, but they had been identified as fluent English speakers at least a year before the study. None of them had learned either natural selection or programming before the study. The study spanned over 7 weeks and was comprised of two study phases. In phase one the subject students learned natural selection in science classroom and how to do programming in NetLogo, an ABPM tool, in a computer lab; in phase two, the subject students were asked to program a simulation of adaptation based on the natural selection model in NetLogo. Both qualitative and quantitative data were collected in this study. The data resources included (1) pre and post test questionnaire, (2) student in-class worksheet, (3) programming planning sheet, (4) code-conception matching sheet, (5) student NetLogo projects, (6) videotaped programming processes, (7) final interview, and (8) investigator's field notes. Both qualitative and quantitative approaches were applied to analyze the gathered data. The findings suggested that students made progress on understanding adaptation phenomena and natural selection at the end of ABPM-supported MBI learning but the progress was limited. These students still held some misconceptions in their conceptual models, such as the idea that animals need to "learn" to adapt into the environment. Besides, their models of natural selection appeared to be

  18. Synthesis of silver nanoparticles using aqueous extracts of Heterotheca inuloides as reducing agent and natural fibers as templates: Agave lechuguilla and silk.

    PubMed

    Morales-Luckie, Raúl A; Lopezfuentes-Ruiz, Aldo Adrián; Olea-Mejía, Oscar F; Liliana, Argueta-Figueroa; Sanchez-Mendieta, Víctor; Brostow, Witold; Hinestroza, Juan P

    2016-12-01

    Silver nanoparticles (Ag NPs) were synthesized using a one-pot green methodology with aqueous extract of Heterotheca inuloides as a reducing agent, and the support of natural fibers: Agave lechuguilla and silk. UV-Vis spectroscopy, X-Ray photoelectron spectroscopy XPS and transmission electron microscopy TEM were used to characterize the resulting bionanocomposite fibers. The average size of the Ag NPs was 16nm and they exhibited low polydispersity. XPS studies revealed the presence of only metallic Ag in the nanoparticles embedded in Agave. lechuguilla fibers. Significant antibacterial activities against gram-negative Escherichia coli and gram-positive Staphylococcus aureus were determined. AgO as well as metallic Ag phases were detected when silk threads were used as a substrates hinting at the active role of substrate during the nucleation and growth of Ag NPs. These bionanocomposites have excellent mechanical properties in tension which in addition to the antibacterial properties indicate the potential use of these modified natural fibers in surgical and biomedical applications. PMID:27612732

  19. Detection of Natural Resistance-Associated Substitutions by Ion Semiconductor Technology in HCV1b Positive, Direct-Acting Antiviral Agents-Naïve Patients

    PubMed Central

    Marascio, Nadia; Pavia, Grazia; Strazzulla, Alessio; Dierckx, Tim; Cuypers, Lize; Vrancken, Bram; Barreca, Giorgio Settimo; Mirante, Teresa; Malanga, Donatella; Oliveira, Duarte Mendes; Vandamme, Anne-Mieke; Torti, Carlo; Liberto, Maria Carla; Focà, Alfredo

    2016-01-01

    Naturally occurring resistance-associated substitutions (RASs) can negatively impact the response to direct-acting antivirals (DAAs) agents-based therapies for hepatitis C virus (HCV) infection. Herein, we set out to characterize the RASs in the HCV1b genome from serum samples of DAA-naïve patients in the context of the SINERGIE (South Italian Network for Rational Guidelines and International Epidemiology, 2014) project. We deep-sequenced the NS3/4A protease region of the viral population using the Ion Torrent Personal Genome Machine, and patient-specific majority rule consensus sequence summaries were constructed with a combination of freely available next generation sequencing data analysis software. We detected NS3/4A protease major and minor variants associated with resistance to boceprevir (V36L), telaprevir (V36L, I132V), simeprevir (V36L), and grazoprevir (V36L, V170I). Furthermore, we sequenced part of HCV NS5B polymerase using Sanger-sequencing and detected a natural RAS for dasabuvir (C316N). This mutation could be important for treatment strategies in cases of previous therapy failure. PMID:27618896

  20. Detection of Natural Resistance-Associated Substitutions by Ion Semiconductor Technology in HCV1b Positive, Direct-Acting Antiviral Agents-Naïve Patients.

    PubMed

    Marascio, Nadia; Pavia, Grazia; Strazzulla, Alessio; Dierckx, Tim; Cuypers, Lize; Vrancken, Bram; Barreca, Giorgio Settimo; Mirante, Teresa; Malanga, Donatella; Oliveira, Duarte Mendes; Vandamme, Anne-Mieke; Torti, Carlo; Liberto, Maria Carla; Focà, Alfredo; The Sinergie-Umg Study Group

    2016-01-01

    Naturally occurring resistance-associated substitutions (RASs) can negatively impact the response to direct-acting antivirals (DAAs) agents-based therapies for hepatitis C virus (HCV) infection. Herein, we set out to characterize the RASs in the HCV1b genome from serum samples of DAA-naïve patients in the context of the SINERGIE (South Italian Network for Rational Guidelines and International Epidemiology, 2014) project. We deep-sequenced the NS3/4A protease region of the viral population using the Ion Torrent Personal Genome Machine, and patient-specific majority rule consensus sequence summaries were constructed with a combination of freely available next generation sequencing data analysis software. We detected NS3/4A protease major and minor variants associated with resistance to boceprevir (V36L), telaprevir (V36L, I132V), simeprevir (V36L), and grazoprevir (V36L, V170I). Furthermore, we sequenced part of HCV NS5B polymerase using Sanger-sequencing and detected a natural RAS for dasabuvir (C316N). This mutation could be important for treatment strategies in cases of previous therapy failure. PMID:27618896

  1. Agent Orange

    MedlinePlus

    ... Index Agent Orange Agent Orange Home Facts about Herbicides Veterans' Diseases Birth Defects Benefits Exposure Locations Provider ... millions of gallons of Agent Orange and other herbicides on trees and vegetation during the Vietnam War. ...

  2. Biodistribution of X-ray iodinated contrast agent in nano-emulsions is controlled by the chemical nature of the oily core.

    PubMed

    Attia, Mohamed F; Anton, Nicolas; Chiper, Manuela; Akasov, Roman; Anton, Halina; Messaddeq, Nadia; Fournel, Sylvie; Klymchenko, Andrey S; Mély, Yves; Vandamme, Thierry F

    2014-10-28

    In this study, we investigated the role of the chemical nature of the oil droplet core of nano-emulsions used as contrast agents for X-ray imaging on their pharmacokinetics and biodistribution. To this end, we formulated PEGylated nano-emulsions with two iodinated oils (i.e., iodinated monoglyceride and iodinated castor oil) and compared them with another iodinated nano-emulsion based on iodinated vitamin E. By using dynamic light scattering and transmission electron microscopy, the three iodinated nano-emulsions were found to exhibit comparable morphologies, size, and surface composition. Furthermore, they were shown to be endowed with very high iodine concentration, which leads to stronger X-ray attenuation properties as compared to the commercial iodinated nano-emulsion Fenestra VC. The three nano-emulsions were i.v. administered in mice and monitored by microcomputed tomography (micro-CT). They showed high contrast enhancement in blood with similar half-life around 6 h but very different accumulation sites. While iodinated monoglycerides exhibited low accumulation in liver and spleen, high accumulation in spleen was observed for iodinated castor oil and in liver for vitamin E. These data clearly highlighted the important role of the oil composition of the nano-emulsion core to obtain strong X-ray contrast enhancement in specific targets such as liver, spleen, or only blood. These differences in biodistribution were partly attributed to differences in the uptake of the nanodroplets by the macrophages in vitro. Another key feature of these nano-emulsions is their long half-elimination time (several weeks), which offers sufficient retention for micro-CT imaging. This work paves the way for the design of nanoparticulate contrast agents for X-ray imaging of selected organs.

  3. Electron beam induced water-soluble silk fibroin nanoparticles as a natural antioxidant and reducing agent for a green synthesis of gold nanocolloid

    NASA Astrophysics Data System (ADS)

    Wongkrongsak, Soraya; Tangthong, Theeranan; Pasanphan, Wanvimol

    2016-01-01

    The research proposes a novel water-soluble silk fibroin nanoparticles (WSSF-NPs) created by electron beam irradiation. In this report, we demonstrate the effects of electron beam irradiation doses ranging from 1 to 30 kGy on the molecular weight (MW), nanostructure formation, antioxidant activity and reducing power of the WSSF-NPs. Electron beam-induced degradation of SF causing MW reduction from 250 to 37 kDa. Chemical characteristic functions of SF still remained after exposing to electron beam. The WSSF-NPs with the MW of 37 kDa exhibited spherical morphology with a nanoscaled size of 40 nm. Antioxidant activities and reducing powers were investigated using 2,2-diphenyl-1-picrylhryl free radical (DPPH•) scavenging activity and ferric reducing antioxidant power (FRAP) assays, respectively. The WSSF-NPs showed greater antioxidant activity and reducing power than non-irradiated SF. By increasing their antioxidant and reducing power efficiencies, WSSF-NPs potentially created gold nanocolloid. WSSF-NPs produced by electron beam irradiation would be a great merit for the uses as a natural antioxidant additive and a green reducing agent in biomedical, cosmetic and food applications.

  4. Biocomposites from Natural Rubber: Synergistic Effects of Functionalized Cellulose Nanocrystals as Both Reinforcing and Cross-Linking Agents via Free-Radical Thiol-ene Chemistry.

    PubMed

    Parambath Kanoth, Bipinbal; Claudino, Mauro; Johansson, Mats; Berglund, Lars A; Zhou, Qi

    2015-08-01

    Natural rubber/cellulose nanocrystals (NR/CNCs) form true biocomposites from renewable resources and are demonstrated to show significantly improved thermo-mechanical properties and reduced stress-softening. The nanocomposites were prepared from chemically functionalized CNCs bearing thiols. CNCs served as both reinforcing and cross-linking agents in the NR matrix, and the study was designed to prove the cross-linking function of modified CNCs. CNCs were prepared from cotton, and the cross-linkable mercapto-groups were introduced onto the surface of CNCs by esterification. Nanocomposite films were prepared by dispersing the modified CNCs (m-CNCs) in NR matrix by solution casting. The cross-links at the filler-matrix (m-CNCs-NR) interface were generated by photochemically initiated thiol-ene reactions as monitored by real-time FTIR analysis. The synergistic effects of reinforcement and chemical cross-linking at the m-CNCs-NR interface on structure, thermo-mechanical, and stress-softening behavior were investigated. Methods included field emission scanning electron microscopy (FE-SEM), swelling tests, dynamic mechanical analysis, and tensile tests. Compared to biocomposites from NR with unmodified CNCs, the NR/m-CNCs nanocomposites showed 2.4-fold increase in tensile strength, 1.6-fold increase in strain-to-failure, and 2.9-fold increase in work-of-fracture at 10 wt % of m-CNCs in NR. PMID:26151647

  5. Biological Agents

    MedlinePlus

    ... to Z Index Contact Us FAQs What's New Biological Agents This page requires that javascript be enabled ... and Health Topics A-Z Index What's New Biological agents include bacteria, viruses, fungi, other microorganisms and ...

  6. Synthesis and in vitro evaluation of (R), (S) and (R/S)-2-hexyne-1,4-diol, a natural product produced by fungus Clitocybe catinus, and related analogs as potential anticancer agents.

    PubMed

    Princival, Iza Mirela R G; Ferreira, Jeiely G; Silva, Teresinha G; Aguiar, Jaciana S; Princival, Jefferson L

    2016-06-15

    The search for natural products and related analogs as potential anticancer agents has seen a significant growth worldwide. Since small sized propargylic diols can be found in nature and chemically synthesized, their evaluation against cancer cells has been of great interest, being a topic of relevance to be investigated. For this purpose, a scalable approach aiming at the synthesis of several propargylic diols and their bioactivity against seven tumor cell lines were evaluated. Interestingly, when the compound 1a, a natural product produced by fungus Clitocybe catinus, was tested in its racemic mixture a more effective activity was observed if compared when enantiopure R-1a or S-1a were tested separately.

  7. A Collective Case Study of Secondary Students' Model-Based Inquiry on Natural Selection through Programming in an Agent-Based Modeling Environment

    ERIC Educational Resources Information Center

    Xiang, Lin

    2011-01-01

    This is a collective case study seeking to develop detailed descriptions of how programming an agent-based simulation influences a group of 8th grade students' model-based inquiry (MBI) by examining students' agent-based programmable modeling (ABPM) processes and the learning outcomes. The context of the present study was a biology unit on…

  8. Comparison of the nucleotide sequences of 16S rRNA, 444 Ep-ank, and groESL heat shock operon genes in naturally occurring Ehrlichia equi and human granulocytic ehrlichiosis agent isolates from Northern California.

    PubMed

    Chae, J S; Foley, J E; Dumler, J S; Madigan, J E

    2000-04-01

    We examined 11 naturally occurring isolates of Ehrlichia equi in horses and two human granulocytic ehrlichiosis agent isolates in California for sequence diversity in three genes. Ehrlichia equi isolates were from Sierra (n = 6), Mendocino (n = 3), Sonoma (n = 1), and Marin (n = 1) counties, and human granulocytic ehrlichiosis (HGE) agent isolates were obtained from Humboldt county. PCR with specific primers for 16S rRNA, 444 Ep-ank and groESL heat shock operon genes successfully produced amplicons for all 13 clinical samples. The 444 Ep-ank gene of the HGE agent and E. equi isolates from northern California is different from the eastern U.S. isolates BDS and USG3. The translated amino acid sequence of the groESL heat shock operon gene fragment is identical among E. equi, the HGE agent, and E. phagocytophila, with the exception of the northern Californian equine CASOLJ isolate. Microheterogeneity was observed in the 16S rRNA gene sequences of HGE agent and E. equi isolates from northern California. These results suggest that E. equi and the HGE agent found in California are similar or identical but may differ from the isolates of equine and human origin found in the eastern United States. PMID:10747108

  9. Detecting agents.

    PubMed Central

    Johnson, Susan C

    2003-01-01

    This paper reviews a recent set of behavioural studies that examine the scope and nature of the representational system underlying theory-of-mind development. Studies with typically developing infants, adults and children with autism all converge on the claim that there is a specialized input system that uses not only morphological cues, but also behavioural cues to categorize novel objects as agents. Evidence is reviewed in which 12- to 15-month-old infants treat certain non-human objects as if they have perceptual/attentional abilities, communicative abilities and goal-directed behaviour. They will follow the attentional orientation of an amorphously shaped novel object if it interacts contingently with them or with another person. They also seem to use a novel object's environmentally directed behaviour to determine its perceptual/attentional orientation and object-oriented goals. Results from adults and children with autism are strikingly similar, despite adults' contradictory beliefs about the objects in question and the failure of children with autism to ultimately develop more advanced theory-of-mind reasoning. The implications for a general theory-of-mind development are discussed. PMID:12689380

  10. Adsorption Study on Moringa Oleifera Seeds and Musa Cavendish as Natural Water Purification Agents for Removal of Lead, Nickel and Cadmium from Drinking Water

    NASA Astrophysics Data System (ADS)

    Aziz, N. A. A.; Jayasuriya, N.; Fan, L.

    2016-07-01

    The effectiveness of plant based materials Moringa oleifera (Moringa) seeds and Musa cavendish (banana peel) for removing heavy metals namely lead (Pb), nickel (Ni) and cadmium (Cd) from contaminated groundwater was studied. Tests were carried out with individual and combined biomass at neutral pH condition on synthetic groundwater samples. The optimum biomass doses were determined as 200 mg/L for single biomass and 400 mg/L (in the ratio of 200 mg/L: 200 mg/L) for combined biomasses and used for adsorption isotherm studies with contact time of 30 minutes. Results showed that combined biomasses was able to met the Pb, Ni and Cd WHO standards from higher Pb, Ni and Cd initial concentrations which were up to 40 µg/L, 50 µg/L 9 µg/L, respectively compared to individual biomass of Moringa seed and banana peel. Moringa seeds exhibited the highest removal of Pb (81%) while the combined biomasses was most effective in removing Ni (74%) and Cd (97%) over wider their initial concentration ranges. The experimental data were linearized with Langmuir and Freundlich adsorption isotherm models. Freundlich model described the Pb adsorption better than the Langmuir model for all the tested biomasses. However, the Langmuir model fit better with the experimental data of Ni adsorption by Moringa seeds. Both models showed negligible differences in the coefficient of determination (R2) when applied for Ni and Cd adsorption on banana peel and combined biomasses, suggesting that there were multiple layers on the biomass interacting with the metals. Chemisorption is suggested to be involved in Pb adsorption for all tested biomasses as the value of nF calculated was lower than one. This type of adsorption could explain the phenomenon of different behavior of Pb removal and the higher Pb adsorption capacity (represented by KF values) compared to Ni and Cd. The study demonstrates that Moringa seeds, banana peel and their combination have the potential to be used as a natural alternative

  11. A procedure for differentiating between the intentional release of biological warfare agents and natural outbreaks of disease: its use in analyzing the tularemia outbreak in Kosovo in 1999 and 2000.

    PubMed

    Grunow, R; Finke, E-J

    2002-08-01

    The events of 11 September and the subsequent anthrax outbreaks in the USA have opened the world's eyes to the threat posed by terrorist groups, criminal organizations and lone operators who will stop at nothing to achieve their goals. The open or covert use of pathogens and toxins as biological warfare agents can no longer be ruled out. Against this background, the appearance of an unusual disease must be studied in order to clarify whether it is a natural or artificially caused occurrence. This issue was recently raised in discussions with local representatives and relief organizations during a tularemia epidemic in Kosovo from October 1999 to May 2000. This paper will present a procedure which attempts to use certain criteria to identify or rule out the use of biological warfare agents in the event of an unusual outbreak of disease. Data and findings gathered by routine epidemiologic and microbiological studies often provide only an indirect answer to this problem. For this reason, various criteria were formulated and points allocated to represent their importance, allowing us to deduce in a semiquantitative manner the degree of possibility of an artificial genesis of outbreaks. The significance and characterization of each criterion are discussed. An analysis of the tularemia epidemic in Kosovo based on the procedure described here indicates that a deliberate release of the causative agent of tularemia, Francisella tularensis, as a biological warfare agent is doubtful. In this paper, an approach is described to discriminate between the intentional use of biological warfare agents and natural outbreaks of infectious diseases. The developed model is flexible and considers the political, military and social analysis of the crisis-afflicted region, the specific features of the pathogen, and the epidemiologic and clinical characteristics of the epidemic.

  12. Toward a Theory-Based Natural Language Capability in Robots and Other Embodied Agents: Evaluating Hausser's SLIM Theory and Database Semantics

    ERIC Educational Resources Information Center

    Burk, Robin K.

    2010-01-01

    Computational natural language understanding and generation have been a goal of artificial intelligence since McCarthy, Minsky, Rochester and Shannon first proposed to spend the summer of 1956 studying this and related problems. Although statistical approaches dominate current natural language applications, two current research trends bring…

  13. Sunscreening Agents

    PubMed Central

    Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B.R.

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents. PMID:23320122

  14. Antiparasitic agents.

    PubMed

    Rosenblatt, J E

    1992-03-01

    In recent years, introduction of new and more effective agents has improved the overall therapy for parasitic infections. This field, however, is still plagued by numerous problems, including the development of resistance to antimicrobial agents (especially with malaria), unavailability of agents in the United States or lack of approval by the Food and Drug Administration, and major toxicities or lack of experience in pregnant women and children, which limits use in these groups of patients. Widespread resistance of Plasmodium falciparum to chloroquine and other agents has complicated the treatment and prophylaxis of this type of malaria. A combination of quinine and Fansidar is usually effective oral therapy for falciparum malaria; quinidine may be administered if intravenous therapy is needed. Mefloquine, which is currently recommended for prophylaxis against chloroquine-resistant P. falciparum, is also effective for single-dose oral treatment, although this regimen has not yet been approved by the Food and Drug Administration. Metronidazole has been widely used for treatment of gastroenteritis due to Entamoeba histolytica and Giardia lamblia (not approved by the Food and Drug Administration for the latter) and is considered safe and effective. A new macrolide, azithromycin, has been reported to be effective for cryptosporidiosis in experimental animals; currently, no effective therapy is available for human infections. Combinations of sulfonamides with other antifolates, trimethoprim or pyrimethamine, are recommended therapy for Pneumocystis carinii pneumonia or toxoplasmosis, respectively. Therapies for the various types of leishmaniasis and trypanosomiasis are complex, often toxic, and often of limited efficacy. The benzimidazoles are effective for roundworm infections, although thiabendazole has severe toxic effects. The recent introduction of ivermectin has revolutionized the treatment and control of onchocerciasis. Another relatively new agent, praziquantel

  15. Synthesis and assignment of absolute configuration of (-)-oleocanthal: a potent, naturally occurring non-steroidal anti-inflammatory and anti-oxidant agent derived from extra virgin olive oils.

    PubMed

    Smith, Amos B; Han, Qiang; Breslin, Paul A S; Beauchamp, Gary K

    2005-10-27

    [structure: see text] Effective total syntheses and the assignment of absolute configurations of both the (+)- and (-)-enantiomers of oleocanthal 1 (a.k.a. deacetoxy ligstroside aglycon), the latter derived from extra virgin olive oils and known to be responsible for the back of the throat irritant properties of olive oils, have been achieved. The absolute and relative stereochemistry of the naturally occurring enantiomer (-)-1 proved to be 3S,4E. Both syntheses begin with d-(-)-ribose, proceed in 12 steps, and are achieved with an overall yield of 7%. Both enantiomers proved to be non-steroidal anti-inflammatory and anti-oxidant agents. PMID:16235961

  16. Antidiabetic Agents.

    ERIC Educational Resources Information Center

    Plummer, Nancy; Michael, Nancy, Ed.

    This module on antidiabetic agents is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then…

  17. Incorporation of dithiooxamide as a complexing agent into cellulose for the removal and pre-concentration of Cu(II) and Cd(II) ions from natural water samples

    NASA Astrophysics Data System (ADS)

    Jorgetto, A. O.; Silva, R. I. V.; Longo, M. M.; Saeki, M. J.; Padilha, P. M.; Martines, M. A. U.; Rocha, B. P.; Castro, G. R.

    2013-01-01

    The present study describes the incorporation of a complexing agent, dithiooxamide, into microcrystalline cellulose for use in the pre-concentration of Cu(II) and Cd(II) ions from aqueous samples. The FTIR spectrum of the adsorbent exhibited an absorption band in the region of 800 cm-1, which confirmed the binding of the silylating agent to the matrix. Elemental analysis indicated the amount of 0.150 mmol g-1 of the complexing agent. The adsorption data were fit to the modified Langmuir equation, and the maximum amount of metal species extracted from the solution, Ns, was determined to be 0.058 and 0.072 mmol g-1 for Cu(II) and Cd(II), respectively. The covering fraction ϕ, which was 0.39 and 0.48 for Cu(II) and Cd(II), respectively, was used to estimate a 1:2 (metal:ligand) ratio in the formed complex, and a binding model was proposed based on this information. The adsorbent was applied in the pre-concentration of natural water samples and exhibited an enrichment factor of approximately 50-fold for the species studied, which enabled its use in the analysis of trace metals in aqueous samples. The system was validated by the analysis of certified standard (1643e), and the adsorbent was stable for more than 20 cycles, thus enabling its safe reutilization.

  18. Studies on chemical modification and biology of a natural product, gambogic acid (II): Synthesis and bioevaluation of gambogellic acid and its derivatives from gambogic acid as antitumor agents.

    PubMed

    Wang, Jinxin; Ma, Junhai; You, Qidong; Zhao, Li; Wang, Fan; Li, Chong; Guo, Qinglong

    2010-09-01

    Gambogic acid (GA) has been reported to be a potent apoptosis inducer. The fact that it is amenable to chemical modification makes GA an attractive molecule for the development of anticancer agents. We firstly reported the synthesis of gambogellic acid, which was generated under acid catalysis from readily available GA by a base-catalyzed diene intramolecular annelation. Sequentially, thirteen new compounds were synthesized and their inhibitory activity on HT-29, Bel-7402, BGC-823, and A549 cell lines were evaluated in vitro by MTT assay, and (38, 40)-epoxy-33-chlorogambogellic acid (4) was identified as a BGC-823 cell apoptosis inducer through MTT cell assay, observations of morphological changes, and Annexin-V/PI double-staining assay. Compound 4 showed significant effects in inducing apoptosis and might serve as a potential lead compound for discovery of new anticancer drugs. Further structure-activity relationships (SARs) of gambogic acid derivatives were discussed.

  19. Dual targets guided screening and isolation of Kukoamine B as a novel natural anti-sepsis agent from traditional Chinese herb Cortex lycii.

    PubMed

    Liu, Xin; Zheng, Xinchuan; Long, Yupeng; Cao, Hongwei; Wang, Ning; Lu, Yongling; Zhao, Kecen; Zhou, Hong; Zheng, Jiang

    2011-01-01

    Treating sepsis remains challenging at present. Bacterial lipopolysaccharide (LPS) and bacterial DNA/CpG DNA are important pathogenic molecules and drug targets for sepsis. It is thus a promising strategy to treat sepsis by discovering agents that neutralize LPS and CpG DNA simultaneously. In this study, we present evidences of the biosensor based screening and isolation of active anti-sepsis fractions and monomers from traditional Chinese herbs using dual targets (LPS and CpG DNA) guided drug discovery strategy. Firstly, LPS or CpG DNA was immobilized on surfaces of cuvettes in the biosensor to establish a screening platform. Then, Cortex lycii with both highest affinities was selected out from one hundred and fourteen traditional Chinese herbs. In subsequent experiments, chromatography was utilized and coupled with the biosensor to purify fractions with a higher affinity for LPS and CpG DNA. In line with affinity assay, these fractions were shown to neutralize LPS and CpG DNA and inhibit their activity in vitro and in vivo. Lastly, the contributing monomer Kukoamine B (KB) was purified. KB neutralized LPS and CpG DNA in vitro. It inhibited TLR4, TLR9 and MyD88 mRNA expressions up-regulated by LPS and CpG DNA, and also attenuated the LPS and CpG DNA elicited nuclear translocation of NF-κB p65 protein in RAW264.7 cells. It also protected mice from lethal challenge of heat-killed E. coli, a mixture of LPS and CpG DNA. In conclusion, we presented a dual target guided discovery of a novel anti-sepsis agent KB from traditional Chinese herbs via combination of biosensor technology and chromatography methods. PMID:21073991

  20. Differential effects of natural product microtubule stabilizers on microtubule assembly: single agent and combination studies with taxol, epothilone B, and discodermolide.

    PubMed

    Gertsch, Jürg; Meier, Sarah; Müller, Martin; Altmann, Karl-Heinz

    2009-01-01

    A systematic comparison has been performed of the morphology and stability of microtubules (MTs) induced by the potent microtubule-stabilizing agents (MSAs) taxol, epothilone B (Epo B), and discodermolide (DDM) under GTP-free conditions. DDM-induced tubulin polymerization occurred significantly faster than that induced by taxol and Epo B. At the same time, tubulin polymers assembled from soluble tubulin by DDM were morphologically distinct (shorter and less ordered) from those induced by either taxol or Epo B, as demonstrated by electron microscopy. Exposure of MSA-induced tubulin polymers to ultrasound revealed the DDM-based polymers to be less stable to this type of physical stress than those formed with either Epo B or taxol. Interestingly, MT assembly in the presence of both DDM and taxol appeared to produce a distinct new type of MT polymer with a mixed morphology between those of DDM- and taxol-induced structures. The observed differences in MT morphology and stability might be related, at least partly, to differences in intramicrotubular tubulin isotype distribution, as DDM showed a different pattern of beta-tubulin isotype usage in the assembly process.

  1. Agent-based modeling of complex infrastructures

    SciTech Connect

    North, M. J.

    2001-06-01

    Complex Adaptive Systems (CAS) can be applied to investigate complex infrastructures and infrastructure interdependencies. The CAS model agents within the Spot Market Agent Research Tool (SMART) and Flexible Agent Simulation Toolkit (FAST) allow investigation of the electric power infrastructure, the natural gas infrastructure and their interdependencies.

  2. KGB agents

    NASA Astrophysics Data System (ADS)

    Gaina, Alex

    A short story is reported in which the activity of Communist Party of the USSR and secret KGB agents, which were payed by the State, in view of controlling of the conscience of population. The story reffers to the Physics Department of the Moscow University, Planing Institute of the Gosplan of Moldavian S.S.R. and Chishinau Technical University (actually: Technical University of Moldova), where the author has worked during Soviet times. Almost every 6-th citizen in the USSR was engaged in this activity, while actually the former communists rule in the Republic of Moldova.

  3. The use of Eucalyptus tereticornis Sm. (Myrtaceae) oil (leaf extract) as a natural larvicidal agent against the malaria vector Anopheles stephensi Liston (Diptera: Culicidae).

    PubMed

    Senthil Nathan, Sengottayan

    2007-07-01

    Secondary metabolites obtained from the indigenous plants with proven mosquito control potential can be used as an alternative to synthetic insecticides under the integrated vector control. The essential oil extract from the forest redgum, Eucalyptus tereticornis Sm. (Myrtaceae) was tested against mature and immature mosquito vector Anopheles stephensi Liston (Diptera) under laboratory condition. The extract showed strong larvicidal, pupicidal and adulticidal activity. The leaf oil extracts showed high bioactivity at high doses. Results obtained from the laboratory experiment showed that the leaf extracts suppressed the pupal and adult activity of Anopheles stephensi at higher doses. In general, first and second instar larvae were more susceptible to all treatments. Clear dose -response relationships were established with the highest dose of 160ppm plant extract evoking almost 100% mortality. The results obtained suggest that, in addition to their medicinal activities, E. tereticornis can also serve as a natural mosquitocide. PMID:16997545

  4. Filling agents.

    PubMed

    Glavas, Ioannis P

    2005-06-01

    Injectable fillers have become an important component of minimally invasive facial rejuvenation modalities. Their ease of use, effectiveness, low morbidity, and fast results with minimal downtime are factors that have made them popular among patients. Soft tissue augmentation has evolved to a unique combination of medicine and art. A wide selection of available agents and new products, each one with unique properties, may be used alone or in combination. The physician acquires the tools to rebalance facial characteristics not only by filling wrinkles but also by having the ability to shape the face and restore bony contours and lines. Careful selection of candidates, realistic expectations, and an understanding of the limitations of fillers are crucial for a successful result.

  5. The influence of oscillating electromagnetic fields on membrane structure and function: Synthetic liposome and natural membrane bilayer systems with direct application to the controlled delivery of chemical agents

    SciTech Connect

    Liburdy, R.P.; de Manincor, D.; Fingado, B.

    1989-09-01

    Investigations have been conducted to determine if an imposed electromagnetic field can influence membrane transport, and ion and drug permeability in both synthetic and natural cell membrane systems. Microwave fields enhance accumulation of sodium in the lymphocyte and induce protein shedding at Tc. Microwaves also trigger membrane permeability of liposome systems under specific field exposure conditions. Sensitivity varies in a defined way in bilayers displaying a membrane structural phase transition temperature, Tc; maximal release was observed at or near Tc. Significantly, liposome systems without a membrane phase transition were also found to experience permeability increases but, in contrast, this response was temperature independent. The above results indicate that field-enhanced drug release occurs in liposome vesicles that possess a Tc as well as non-Tc liposomes. Additional studies extend non-Tc liposome responses to the in vivo case in which microwaves trigger Gentamicin release from a liposome depot'' placed subcutaneously in the rat hind leg. In addition, evidence is provided that cell surface sequestered liposomes can be triggered by microwave fields to release drugs directly into target cells. 24 refs., 6 figs.

  6. Ethanol Extracts from Mistletoe (Viscum album L.) Act as Natural Antioxidants and Antimicrobial Agents in Uncooked Pork Patties during Refrigerated Storage

    PubMed Central

    Kang, Suk-Nam

    2016-01-01

    The antioxidant potential of mistletoe (Viscum album L. var. coloratum Ohwi; VAL) extract in uncooked pork patties was evaluated. Three concentrations of VAL extract (0.1 [T1], 0.5% [T2] and 1.0% [T3]) along with 0.02% ascorbic acid as a positive control (V) were added to ground pork and pork patties were prepared. Incorporation of VAL extract decreased (p<0.05) the pH of the pork patties throughout the storage time and reduced (p<0.01) the thiobarbituric acid reactive substance values after day 14 of storage. Total plate counts of the VAL extract-treated samples and V-treated samples were also significantly lower (p<0.01) than that of the control (C) throughout the storage period. In addition, odor scores of the VAL extract-treated patties were lower than those of the C- or V-treated samples on 3rd day of the storage period. These results demonstrated that the VAL extract acts as a natural antioxidant in uncooked pork products. PMID:26732334

  7. Exploration on natural product anibamine side chain modification toward development of novel CCR5 antagonists and potential anti-prostate cancer agents.

    PubMed

    Xu, Guoyan G; Zaidi, Saheem A; Zhang, Feng; Singh, Shilpa; Raborg, Thomas J; Yuan, Yunyun; Zhang, Yan

    2015-09-01

    Prostate cancer is one of the leading causes of death among males in the world. Prostate cancer cells have been shown to express upregulated chemokine receptor CCR5, a G protein-coupled receptor (GPCR) that relates to the inflammation process. Anibamine, a natural product containing a pyridine ring and two aliphatic side chains, was shown to carry a binding affinity of 1 μM at CCR5 as an antagonist with potential anti-cancer activity. However, it is not drug-like according to the Lipinski's rule of five mainly due to its two long aliphatic side chains. In our effort to improve its drug-like property, a series of anibamine derivatives were designed and synthesized by placement of aromatic side chains through an amide linkage to the pyridine ring. The newly synthesized compounds were tested for their CCR5 affinity and antagonism, and potential anti-proliferation activity against prostate cancer cell lines. Basal cytotoxicity was finally studied for compounds showing potent anti-proliferation activity. It was found that compounds with hydrophobic substitutions on the aromatic systems seemed to carry more promising CCR5 binding and prostate cancer cell proliferation inhibition activities.

  8. Influence of heat on biological activity and concentration of oleocanthal--a natural anti-inflammatory agent in virgin olive oil.

    PubMed

    Cicerale, Sara; Conlan, Xavier A; Barnett, Neil W; Sinclair, Andrew J; Keast, Russell S J

    2009-02-25

    The olive oil phenolic oleocanthal is a natural nonsteroidal anti-inflammatory compound that irritates the oral pharynx in a dose-dependent manner. It has been proposed that the biological activity of oleocanthal is partially responsible for the beneficial health effects of the Mediterranean diet. Virgin olive oil containing oleocanthal is often added as an ingredient in a number of cooked dishes, and therefore it is of great importance to understand how best to preserve the putative health-promoting benefits of this compound, as olive oil phenolics are subject to degradation upon heating in general. One extra virgin olive oil containing 53.9 mg/kg oleocanthal was heated at various temperatures (100, 170, and 240 degrees C) for set time periods (0, 1, 5, 20, 60, and 90 min). Oleocanthal concentrations were quantified using HPLC, and its biological activity was determined with a taste bioassay measuring the intensity of throat irritation. Results demonstrated that oleocanthal was heat stable compared with other olive oil phenolics, with a maximum loss of 16% as determined by HPLC analysis. However, there was a significant decrease of up to 31% (p < 0.05) in the biological activity of oleocanthal as determined by the taste bioassay. Although there was minimal degradation of oleocanthal concentration, there was a significant decrease in the biological activity of oleocanthal upon extended heating time, indicating a possible loss of the putative health -benefiting properties of oleocanthal. Alternatively, the difference in the concentration and biological activity of oleocanthal after heat treatment could be a result of an oleocanthal antagonist forming, decreasing or masking the biological activity of oleocanthal. PMID:19166297

  9. Polish Natural Bee Honeys Are Anti-Proliferative and Anti-Metastatic Agents in Human Glioblastoma multiforme U87MG Cell Line

    PubMed Central

    Moskwa, Justyna; Borawska, Maria H.; Markiewicz-Zukowska, Renata; Puscion-Jakubik, Anna; Naliwajko, Sylwia K.; Socha, Katarzyna; Soroczynska, Jolanta

    2014-01-01

    Honey has been used as food and a traditional medicament since ancient times. However, recently many scientists have been concentrating on the anti-oxidant, anti-proliferative, anti-inflammatory and other properties of honey. In this study, we investigated for the first time an anticancer effect of different honeys from Poland on tumor cell line - glioblastoma multiforme U87MG. Anti-proliferative activity of honeys and its interferences with temozolomide were determined by a cytotoxicity test and DNA binding by [H3]-thymidine incorporation. A gelatin zymography was used to conduct an evaluation of metalloproteinases (MMP-2 and MMP-9) expression in U87MG treatment with honey samples. The honeys were previously tested qualitatively (diastase activity, total phenolic content, lead and cadmium content). The data demonstrated that the examined honeys have a potent anti-proliferative effect on U87MG cell line in a time- and dose-dependent manner, being effective at concentrations as low as 0.5% (multifloral light honey - viability 53% after 72 h of incubation). We observed that after 48 h, combining honey with temozolomide showed a significantly higher inhibitory effect than the samples of honey alone. We observed a strong inhibition of MMP-2 and MMP-9 for the tested honeys (from 20 to 56% and from 5 to 58% compared to control, respectively). Our results suggest that Polish honeys have an anti-proliferative and anti-metastatic effect on U87MG cell line. Therefore, natural bee honey can be considered as a promising adjuvant treatment for brain tumors. PMID:24594866

  10. Polish natural bee honeys are anti-proliferative and anti-metastatic agents in human glioblastoma multiforme U87MG cell line.

    PubMed

    Moskwa, Justyna; Borawska, Maria H; Markiewicz-Zukowska, Renata; Puscion-Jakubik, Anna; Naliwajko, Sylwia K; Socha, Katarzyna; Soroczynska, Jolanta

    2014-01-01

    Honey has been used as food and a traditional medicament since ancient times. However, recently many scientists have been concentrating on the anti-oxidant, anti-proliferative, anti-inflammatory and other properties of honey. In this study, we investigated for the first time an anticancer effect of different honeys from Poland on tumor cell line - glioblastoma multiforme U87MG. Anti-proliferative activity of honeys and its interferences with temozolomide were determined by a cytotoxicity test and DNA binding by [H3]-thymidine incorporation. A gelatin zymography was used to conduct an evaluation of metalloproteinases (MMP-2 and MMP-9) expression in U87MG treatment with honey samples. The honeys were previously tested qualitatively (diastase activity, total phenolic content, lead and cadmium content). The data demonstrated that the examined honeys have a potent anti-proliferative effect on U87MG cell line in a time- and dose-dependent manner, being effective at concentrations as low as 0.5% (multifloral light honey - viability 53% after 72 h of incubation). We observed that after 48 h, combining honey with temozolomide showed a significantly higher inhibitory effect than the samples of honey alone. We observed a strong inhibition of MMP-2 and MMP-9 for the tested honeys (from 20 to 56% and from 5 to 58% compared to control, respectively). Our results suggest that Polish honeys have an anti-proliferative and anti-metastatic effect on U87MG cell line. Therefore, natural bee honey can be considered as a promising adjuvant treatment for brain tumors.

  11. Use of eugenol-lean clove extract as a flavoring agent and natural antioxidant in mayonnaise: product characterization and storage study.

    PubMed

    Chatterjee, Dipan; Bhattacharjee, Paramita

    2015-08-01

    Eugenol-lean fraction (98 % lower eugenol content than eugenol-rich fraction) having appreciable phytochemical properties was selectively isolated from clove buds (Syzygium aromaticum Linn) using supercritical carbon dioxide extraction at 40 °C and pressure of 25 MPa with static and dynamic time of 120 and 30 min respectively using ground clove powder which was previously subjected to steam distillation. The extract was used as a flavor ingredient (replacing mustard in classical formulation) and also as a source of natural antioxidant in formulating a new mayonnaise product to improve its nutraceutical value and shelf-life. This product was found to be comparable to the mustard formulated sample (experimental control) organoleptically. The sample did not have typical pungency of clove and had improved physical properties such as increased color tonality with higher chroma values, lower thermal and non-thermal creaming, homogenous and compact microstructure and higher consistency index vis-à-vis the control and standard market samples, even at the end of the storage period of 6 months. Mayonnaise formulated with eugenol-lean clove extract had significantly higher antioxidant activity (IC50 = 10.85 mg/mL), phenolic content (1.89 mg gallic acid equivalent/g mayonnaise) and reducing power (11.29 mg BHT equivalent/g mayonnaise) than mustard-formulated mayonnaise and the market sample. While, the antioxidant activity and phytochemical properties tend to decrease after 30 days for the reference market sample and after 90 days for the experimental control sample, the mayonnaise formulated with eugenol-lean clove extract was found to be stable beyond 6 months.

  12. Cysteine S-conjugate β-lyases: Important roles in the metabolism of naturally occurring sulfur and selenium-containing compounds, xenobiotics and anticancer agents

    PubMed Central

    Cooper, Arthur J. L.; Krasnikov, Boris F.; Niatsetskaya, Zoya V.; Pinto, John T.; Callery, Patrick S.; Villar, Maria T.; Artigues, Antonio; Bruschi, Sam A.

    2010-01-01

    Summary Cysteine S-conjugate β-lyases are pyridoxal 5′-phosphate-containing enzymes that catalyze β-elimination reactions with cysteine S-conjugates that possess a good leaving group in the β-position. The end products are aminoacrylate and a sulfur-containing fragment. The aminoacrylate tautomerizes and hydrolyzes to pyruvate and ammonia. The mammalian cysteine S-conjugate β-lyases thus far identified are enzymes involved in amino acid metabolism that catalyze β-lyase reactions as non-physiological side reactions. Most are aminotransferases. In some cases the lyase is inactivated by reaction products. The cysteine S-conjugate β-lyases are of much interest to toxicologists because they play an important key role in the bioactivation (toxication) of halogenated alkenes, some of which are produced on an industrial scale and are environmental contaminants. The cysteine S-conjugate β-lyases have been reviewed in this journal previously [Cooper and Pinto, 2006]. Here we focus on more recent findings regarding: 1) the identification of enzymes associated with high-Mr cysteine S-conjugate β-lyases in the cytosolic and mitochondrial fractions of rat liver and kidney; 2) the mechanism of syncatalytic inactivation of rat liver mitochondrial aspartate aminotransferase by the nephrotoxic β-lyase substrate S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (the cysteine S-conjugate of tetrafluoroethylene); 3) toxicant channeling of reactive fragments from the active site of mitochondrial aspartate aminotransferase to susceptible proteins in the mitochondria; 4) the involvement of cysteine S-conjugate β-lyases in the metabolism/bioactivation of drugs and natural products; and 5) the role of cysteine S-conjugate β-lyases in the metabolism of selenocysteine Se-conjugates. This review emphasizes the fact that the cysteine S-conjugate β-lyases are biologically more important than hitherto appreciated. PMID:20306345

  13. Cysteine S-conjugate β-lyases: important roles in the metabolism of naturally occurring sulfur and selenium-containing compounds, xenobiotics and anticancer agents.

    PubMed

    Cooper, Arthur J L; Krasnikov, Boris F; Niatsetskaya, Zoya V; Pinto, John T; Callery, Patrick S; Villar, Maria T; Artigues, Antonio; Bruschi, Sam A

    2011-06-01

    Cysteine S-conjugate β-lyases are pyridoxal 5'-phosphate-containing enzymes that catalyze β-elimination reactions with cysteine S-conjugates that possess a good leaving group in the β-position. The end products are aminoacrylate and a sulfur-containing fragment. The aminoacrylate tautomerizes and hydrolyzes to pyruvate and ammonia. The mammalian cysteine S-conjugate β-lyases thus far identified are enzymes involved in amino acid metabolism that catalyze β-lyase reactions as non-physiological side reactions. Most are aminotransferases. In some cases the lyase is inactivated by reaction products. The cysteine S-conjugate β-lyases are of much interest to toxicologists because they play an important key role in the bioactivation (toxication) of halogenated alkenes, some of which are produced on an industrial scale and are environmental contaminants. The cysteine S-conjugate β-lyases have been reviewed in this journal previously (Cooper and Pinto in Amino Acids 30:1-15, 2006). Here, we focus on more recent findings regarding: (1) the identification of enzymes associated with high-M(r) cysteine S-conjugate β-lyases in the cytosolic and mitochondrial fractions of rat liver and kidney; (2) the mechanism of syncatalytic inactivation of rat liver mitochondrial aspartate aminotransferase by the nephrotoxic β-lyase substrate S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (the cysteine S-conjugate of tetrafluoroethylene); (3) toxicant channeling of reactive fragments from the active site of mitochondrial aspartate aminotransferase to susceptible proteins in the mitochondria; (4) the involvement of cysteine S-conjugate β-lyases in the metabolism/bioactivation of drugs and natural products; and (5) the role of cysteine S-conjugate β-lyases in the metabolism of selenocysteine Se-conjugates. This review emphasizes the fact that the cysteine S-conjugate β-lyases are biologically more important than hitherto appreciated.

  14. Influence of heat on biological activity and concentration of oleocanthal--a natural anti-inflammatory agent in virgin olive oil.

    PubMed

    Cicerale, Sara; Conlan, Xavier A; Barnett, Neil W; Sinclair, Andrew J; Keast, Russell S J

    2009-02-25

    The olive oil phenolic oleocanthal is a natural nonsteroidal anti-inflammatory compound that irritates the oral pharynx in a dose-dependent manner. It has been proposed that the biological activity of oleocanthal is partially responsible for the beneficial health effects of the Mediterranean diet. Virgin olive oil containing oleocanthal is often added as an ingredient in a number of cooked dishes, and therefore it is of great importance to understand how best to preserve the putative health-promoting benefits of this compound, as olive oil phenolics are subject to degradation upon heating in general. One extra virgin olive oil containing 53.9 mg/kg oleocanthal was heated at various temperatures (100, 170, and 240 degrees C) for set time periods (0, 1, 5, 20, 60, and 90 min). Oleocanthal concentrations were quantified using HPLC, and its biological activity was determined with a taste bioassay measuring the intensity of throat irritation. Results demonstrated that oleocanthal was heat stable compared with other olive oil phenolics, with a maximum loss of 16% as determined by HPLC analysis. However, there was a significant decrease of up to 31% (p < 0.05) in the biological activity of oleocanthal as determined by the taste bioassay. Although there was minimal degradation of oleocanthal concentration, there was a significant decrease in the biological activity of oleocanthal upon extended heating time, indicating a possible loss of the putative health -benefiting properties of oleocanthal. Alternatively, the difference in the concentration and biological activity of oleocanthal after heat treatment could be a result of an oleocanthal antagonist forming, decreasing or masking the biological activity of oleocanthal.

  15. Health care agents

    MedlinePlus

    Durable power of attorney for health care; Health care proxy; End-of-life - health care agent; Life support treatment - ... Respirator - health care agent; Ventilator - health care agent; Power of attorney - health care agent; POA - health care ...

  16. Intelligent Agent Architectures: Reactive Planning Testbed

    NASA Technical Reports Server (NTRS)

    Rosenschein, Stanley J.; Kahn, Philip

    1993-01-01

    An Integrated Agent Architecture (IAA) is a framework or paradigm for constructing intelligent agents. Intelligent agents are collections of sensors, computers, and effectors that interact with their environments in real time in goal-directed ways. Because of the complexity involved in designing intelligent agents, it has been found useful to approach the construction of agents with some organizing principle, theory, or paradigm that gives shape to the agent's components and structures their relationships. Given the wide variety of approaches being taken in the field, the question naturally arises: Is there a way to compare and evaluate these approaches? The purpose of the present work is to develop common benchmark tasks and evaluation metrics to which intelligent agents, including complex robotic agents, constructed using various architectural approaches can be subjected.

  17. Naturally occurring anti-Salmonella agents.

    PubMed

    Kubo, I; Fujita, K

    2001-12-01

    Polygodial and (2E)-hexenal were found to possess antibacterial activity against Salmonella choleraesuis with the minimum bactericidal concentrations (MBC) of 50 microg/mL (0.17 mM) and 100 microg/mL (0.98 mM), respectively. The time kill curve study showed that these two alpha,beta-unsaturated aldehydes were bactericidal against this food-borne bacterium at any stage of growth. However, they showed different effects on the growth of S. choleraesuis. The combination of polygodial and anethole exhibited strong synergism on their bacteriostatic action but only marginal synergism on their bactericidal action. PMID:11743758

  18. Actinopyga lecanora Hydrolysates as Natural Antibacterial Agents

    PubMed Central

    Ghanbari, Raheleh; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Ismail, Amin; Saari, Nazamid

    2012-01-01

    Actinopyga lecanora, a type of sea cucumber commonly known as stone fish with relatively high protein content, was explored as raw material for bioactive peptides production. Six proteolytic enzymes, namely alcalase, papain, pepsin, trypsin, bromelain and flavourzyme were used to hydrolyze A. lecanora at different times and their respective degrees of hydrolysis (DH) were calculated. Subsequently, antibacterial activity of the A. lecanora hydrolysates, against some common pathogenic Gram positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Pseudomonas sp.) were evaluated. Papain hydrolysis showed the highest DH value (89.44%), followed by alcalase hydrolysis (83.35%). Bromelain hydrolysate after one and seven hours of hydrolysis exhibited the highest antibacterial activities against Pseudomonas sp., P. aeruginosa and E. coli at 51.85%, 30.07% and 30.45%, respectively compared to the other hydrolysates. Protein hydrolysate generated by papain after 8 h hydrolysis showed maximum antibacterial activity against S. aureus at 20.19%. The potent hydrolysates were further fractionated using RP-HPLC and antibacterial activity of the collected fractions from each hydrolysate were evaluated, wherein among them only three fractions from the bromelain hydrolysates exhibited inhibitory activities against Pseudomonas sp., P. aeruginosa and E. coli at 24%, 25.5% and 27.1%, respectively and one fraction of papain hydrolysate showed antibacterial activity of 33.1% against S. aureus. The evaluation of the relationship between DH and antibacterial activities of papain and bromelain hydrolysates revealed a meaningful correlation of four and six order functions. PMID:23222684

  19. Plant extracts as natural amoebicidal agents.

    PubMed

    Derda, Monika; Hadaś, Edward; Thiem, Barbara

    2009-02-01

    Strains of Acanthamoeba sp. constitute a factor contributing to the occurrence of chronic granulomatous amoebic encephalitis, keratitis, pneumonia, as well as inflammations of other organs. Treatment of these diseases is very difficult and not always effective. A majority of these infections have been fatal. The aim of our study was to examine the amoebicidal or amoebistatic activity of plant extracts from Rubus chamaemorus, Pueraria lobata, Solidago virgaurea and Solidago graminifolia. For the purpose of isolation of pharmacologically active substances, we used the aboveground parts of plants, together with flowers, roots and leaves. It was established that extracts from S. virgauera, P. lobata and R. chamaemorus displayed chemotherapeutic properties in vitro in concentrations of approximately 0.01-0.05 mg extract/mL, i.e., in concentrations of 0.350 microg/mL expressed in ellagic acid for R. chamaemorus and 0.053 microg/mL expressed in puerarin for P. lobata. Therapeutic index values is 3.5-20. As a result of in vivo experiments, it was found out that, following therapy using the extracts, animals infected with Acanthamoeba sp. survived for an extended period (2.5-3 times longer). It was determined that plant extracts may be used both externally and internally in the case of a combined therapy for acanthamoebiasis. The tested extracts are not toxic for animals.

  20. Preparing Change Agents for Change Agent Roles.

    ERIC Educational Resources Information Center

    Sedlacek, James R.

    Seventy-seven Spanish- and Portuguese-speaking agricultural change agents from developing Central and South American countries responded to a questionnaire which sought perceptions of the roles in which the change agents felt they were involved and the roles for which they felt they were being trained. The agents were participating in training…

  1. Antagonistic formation motion of cooperative agents

    NASA Astrophysics Data System (ADS)

    Lu, Wan-Ting; Dai, Ming-Xiang; Xue, Fang-Zheng

    2015-02-01

    This paper investigates a new formation motion problem of a class of first-order multi-agent systems with antagonistic interactions. A distributed formation control algorithm is proposed for each agent to realize the antagonistic formation motion. A sufficient condition is derived to ensure that all of the agents make an antagonistic formation motion in a distributed manner. It is shown that all of the agents can be spontaneously divided into several groups and that agents in the same group collaborate while agents in different groups compete. Finally, a numerical simulation is included to demonstrate our theoretical results. Project supported by the National Natural Science Foundation of China (Grant Nos. 61203080 and 61473051) and the Natural Science Foundation of Chongqing City (Grant No. CSTC 2011BB0081).

  2. Remote Agent Demonstration

    NASA Technical Reports Server (NTRS)

    Dorais, Gregory A.; Kurien, James; Rajan, Kanna

    1999-01-01

    We describe the computer demonstration of the Remote Agent Experiment (RAX). The Remote Agent is a high-level, model-based, autonomous control agent being validated on the NASA Deep Space 1 spacecraft.

  3. Collaborating with Autonomous Agents

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Cross, Charles D.; Fan, Henry; Hempley, Lucas E.; Motter, Mark A.; Neilan, James H.; Qualls, Garry D.; Rothhaar, Paul M.; Tran, Loc D.; Allen, B. Danette

    2015-01-01

    With the anticipated increase of small unmanned aircraft systems (sUAS) entering into the National Airspace System, it is highly likely that vehicle operators will be teaming with fleets of small autonomous vehicles. The small vehicles may consist of sUAS, which are 55 pounds or less that typically will y at altitudes 400 feet and below, and small ground vehicles typically operating in buildings or defined small campuses. Typically, the vehicle operators are not concerned with manual control of the vehicle; instead they are concerned with the overall mission. In order for this vision of high-level mission operators working with fleets of vehicles to come to fruition, many human factors related challenges must be investigated and solved. First, the interface between the human operator and the autonomous agent must be at a level that the operator needs and the agents can understand. This paper details the natural language human factors e orts that NASA Langley's Autonomy Incubator is focusing on. In particular these e orts focus on allowing the operator to interact with the system using speech and gestures rather than a mouse and keyboard. With this ability of the system to understand both speech and gestures, operators not familiar with the vehicle dynamics will be able to easily plan, initiate, and change missions using a language familiar to them rather than having to learn and converse in the vehicle's language. This will foster better teaming between the operator and the autonomous agent which will help lower workload, increase situation awareness, and improve performance of the system as a whole.

  4. Biological agents and pregnancy.

    PubMed

    Ekblad, U

    1995-08-01

    Pregnant women are exposed to many biological, eg microbial, agents, which are potentially harmful to the fetus. The reported rates of vertical transmission of hepatitis B and human immunodeficiency virus vary between 3 to 90% and 0 to 65%, respectively. The susceptibility to hepatitis B and human immunodeficiency infection is increased in pregnant physicians, midwives, and nurses because of the bloodborne nature of these viruses. Also, TORCH (toxoplasmosis-rubella-cytomegalovirus-herpes) infections, acquired during pregnancy, may result in congenital infection, and serious sequelae in the neonatal period or years after birth. Schoolteachers and daycare personnel have an increased risk of perinatal varicella, "fifth disease," and mumps. Perinatal listeriosis affects one in 20,000 births and may result in fetal wastage. Because of the risk of the possibility of vertical transmission, immunization during pregnancy with live virus vaccines is not recommended. PMID:8520961

  5. Biological warfare agents.

    PubMed

    Pohanka, Miroslav; Kuca, Kamil

    2010-01-01

    Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological warfare agents and epidemiology of infections are described. The last section tries to estimate future trends in research on biological warfare agents.

  6. Spacecraft sanitation agent development

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The development of an effective sanitizing agent that is compatible with the spacecraft environment and the human occupant is discussed. Experimental results show that two sanitation agents must be used to satisfy mission requirements: one agent for personal hygiene and one for equipment maintenance. It was also recommended that a water rinse be used with the agents for best results, and that consideration be given to using the agents pressure packed or in aerosol formulations.

  7. An Agent-Based Data Mining System for Ontology Evolution

    NASA Astrophysics Data System (ADS)

    Hadzic, Maja; Dillon, Darshan

    We have developed an evidence-based mental health ontological model that represents mental health in multiple dimensions. The ongoing addition of new mental health knowledge requires a continual update of the Mental Health Ontology. In this paper, we describe how the ontology evolution can be realized using a multi-agent system in combination with data mining algorithms. We use the TICSA methodology to design this multi-agent system which is composed of four different types of agents: Information agent, Data Warehouse agent, Data Mining agents and Ontology agent. We use UML 2.1 sequence diagrams to model the collaborative nature of the agents and a UML 2.1 composite structure diagram to model the structure of individual agents. The Mental Heath Ontology has the potential to underpin various mental health research experiments of a collaborative nature which are greatly needed in times of increasing mental distress and illness.

  8. Pyranone Natural Products as Inspirations for Catalytic Reaction Discovery and Development

    PubMed Central

    McDonald, Benjamin R.; Scheidt, Karl A.

    2015-01-01

    . A bifunctional hydrogen bonding/ Brønstead base catalyst was ultimately found to enable this transformation in analogous manner to the biosynthesis via the enzyme chalcone isomerase. Employing thiourea catalysts derived from the pseudoenantiomeric quinine and quinidine, alkylidene β-ketoesters can be isomerized to 3-carboxy flavanones and decarboxylated in a single pot operation to stereodivergently provide highly enantioenriched flavanones in excellent yield. This method was applied to the synthesis of the abyssinone family of natural products, as well as the rotenoid, deguelin. An analogous method to isomerize chalcones was developed and applied to the synthesis of isosilybin A. In both of these related endeavors, the need for novel enabling methodologies toward the efficient creation of targeted molecular complexity drove the discovery, development and deployment of these stereoselective catalytic transformations. PMID:25742935

  9. Chemical warfare agents.

    PubMed

    Chauhan, S; Chauhan, S; D'Cruz, R; Faruqi, S; Singh, K K; Varma, S; Singh, M; Karthik, V

    2008-09-01

    Chemical warfare agents (CWA's) are defined as any chemical substance whose toxic properties are utilised to kill, injure or incapacitate an enemy in warfare and associated military operations. Chemical agents have been used in war since times immemorial, but their use reached a peak during World War I. During World War II only the Germans used them in the infamous gas chambers. Since then these have been intermittently used both in war and acts of terrorisms. Many countries have stockpiles of these agents. There has been a legislative effort worldwide to ban the use of CWA's under the chemical weapons convention which came into force in 1997. However the manufacture of these agents cannot be completely prohibited as some of them have potential industrial uses. Moreover despite the remedial measures taken so far and worldwide condemnation, the ease of manufacturing these agents and effectiveness during combat or small scale terrorist operations still make them a powerful weapon to reckon with. These agents are classified according to mechanism of toxicity in humans into blister agents, nerve agents, asphyxiants, choking agents and incapacitating/behavior altering agents. Some of these agents can be as devastating as a nuclear bomb. In addition to immediate injuries caused by chemical agents, some of them are associated with long term morbidities and psychological problems. In this review we will discuss briefly about the historical background, properties, manufacture techniques and industrial uses, mechanism of toxicity, clinical features of exposure and pharmacological management of casualties caused by chemical agents. PMID:21783898

  10. An Immune Agent for Web-Based AI Course

    ERIC Educational Resources Information Center

    Gong, Tao; Cai, Zixing

    2006-01-01

    To overcome weakness and faults of a web-based e-learning course such as Artificial Intelligence (AI), an immune agent was proposed, simulating a natural immune mechanism against a virus. The immune agent was built on the multi-dimension education agent model and immune algorithm. The web-based AI course was comprised of many files, such as HTML…

  11. Environmental mimics of chemical warfare agents.

    PubMed

    Claborn, David M

    2004-12-01

    There are several natural and artificial factors that mimic the effects of chemical warfare agents, thereby causing unwarranted alarm and confusion on the battlefield. Symptoms associated with chemical warfare include paralysis, muscle tremors, heavy salivation, severe burns, blistering, and corrosive skin injuries among others. Similar symptoms can be produced from a variety of environmental sources, artificial and natural. This article reviews several published and unpublished examples of environmental factors that produce syndromes similar to those caused by these agents. Examples of such mimics include pesticides, blistering exudates from insects and plants, various types of bites, and naturally occurring diseases. The potential for confusion caused by these factors is discussed and means of discriminating between warfare agents and naturally occurring events are identified. Recommendations for the use of this information and for needed research are also discussed. PMID:15646185

  12. Mobile Agents Applications.

    ERIC Educational Resources Information Center

    Martins, Rosane Maria; Chaves, Magali Ribeiro; Pirmez, Luci; Rust da Costa Carmo, Luiz Fernando

    2001-01-01

    Discussion of the need to filter and retrieval relevant information from the Internet focuses on the use of mobile agents, specific software components which are based on distributed artificial intelligence and integrated systems. Surveys agent technology and discusses the agent building package used to develop two applications using IBM's Aglet…

  13. Hydroxypyridonate chelating agents

    DOEpatents

    Raymond, Kenneth N.; Scarrow, Robert C.; White, David L.

    1987-01-01

    Chelating agents having 1-hydroxy-2-pyridinone (HOPO) and related moieties incorporated within their structures, including polydentate HOPO-substituted polyamines such as spermidine and spermine, and HOPO-substituted desferrioxamine. The chelating agents are useful in selectively removing certain cations from solution, and are particularly useful as ferric ion and actinide chelators. Novel syntheses of the chelating agents are provided.

  14. Petri Nets as Modeling Tool for Emergent Agents

    NASA Technical Reports Server (NTRS)

    Bergman, Marto

    2004-01-01

    Emergent agents, those agents whose local interactions can cause unexpected global results, require a method of modeling that is both dynamic and structured Petri Nets, a modeling tool developed for dynamic discrete event system of mainly functional agents, provide this, and have the benefit of being an established tool. We present here the details of the modeling method here and discuss how to implement its use for modeling agent-based systems. Petri Nets have been used extensively in the modeling of functional agents, those agents who have defined purposes and whose actions should result in a know outcome. However, emergent agents, those agents who have a defined structure but whose interaction causes outcomes that are unpredictable, have not yet found a modeling style that suits them. A problem with formally modeling emergent agents that any formal modeling style usually expects to show the results of a problem and the results of problems studied using emergent agents are not apparent from the initial construction. However, the study of emergent agents still requires a method to analyze the agents themselves, and have sensible conversation about the differences and similarities between types of emergent agents. We attempt to correct this problem by applying Petri Nets to the characterization of emergent agents. In doing so, the emergent properties of these agents can be highlighted, and conversation about the nature and compatibility of the differing methods of agent creation can begin.

  15. Standard Agent Framework 1

    SciTech Connect

    Goldsmith, Steven Y.

    1999-04-06

    The Standard Agent framework provides an extensible object-oriented development environment suitable for use in both research and applications projects. The SAF provides a means for constructing and customizing multi-agent systems through specialization of standard base classes (architecture-driven framework) and by composition of component classes (data driven framework). The standard agent system is implemented as an extensible object-centerd framework. Four concrete base classes are developed: (1) Standard Agency; (2) Standard Agent; (3) Human Factor, and (4) Resources. The object-centered framework developed and utilized provides the best comprimise between generality and flexibility available in agent development systems today.

  16. Phytonutrients as therapeutic agents.

    PubMed

    Gupta, Charu; Prakash, Dhan

    2014-09-01

    Nutrients present in various foods plays an important role in maintaining the normal functions of the human body. The major nutrients present in foods include carbohydrates, proteins, lipids, vitamins, and minerals. Besides these, there are some bioactive food components known as "phytonutrients" that play an important role in human health. They have tremendous impact on the health care system and may provide medical health benefits including the prevention and/or treatment of disease and various physiological disorders. Phytonutrients play a positive role by maintaining and modulating immune function to prevent specific diseases. Being natural products, they hold a great promise in clinical therapy as they possess no side effects that are usually associated with chemotherapy or radiotherapy. They are also comparatively cheap and thus significantly reduce health care cost. Phytonutrients are the plant nutrients with specific biological activities that support human health. Some of the important bioactive phytonutrients include polyphenols, terpenoids, resveratrol, flavonoids, isoflavonoids, carotenoids, limonoids, glucosinolates, phytoestrogens, phytosterols, anthocyanins, ω-3 fatty acids, and probiotics. They play specific pharmacological effects in human health such as anti-microbial, anti-oxidants, anti-inflammatory, antiallergic, anti-spasmodic, anti-cancer, anti-aging, hepatoprotective, hypolipidemic, neuroprotective, hypotensive, diabetes, osteoporosis, CNS stimulant, analgesic, protection from UVB-induced carcinogenesis, immuno-modulator, and carminative. This mini-review attempts to summarize the major important types of phytonutrients and their role in promoting human health and as therapeutic agents along with the current market trend and commercialization.

  17. Agent Architectures for Compliance

    NASA Astrophysics Data System (ADS)

    Burgemeestre, Brigitte; Hulstijn, Joris; Tan, Yao-Hua

    A Normative Multi-Agent System consists of autonomous agents who must comply with social norms. Different kinds of norms make different assumptions about the cognitive architecture of the agents. For example, a principle-based norm assumes that agents can reflect upon the consequences of their actions; a rule-based formulation only assumes that agents can avoid violations. In this paper we present several cognitive agent architectures for self-monitoring and compliance. We show how different assumptions about the cognitive architecture lead to different information needs when assessing compliance. The approach is validated with a case study of horizontal monitoring, an approach to corporate tax auditing recently introduced by the Dutch Customs and Tax Authority.

  18. 13 CFR 107.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Functions of agents, including... Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS INVESTMENT COMPANIES SBA Financial Assistance for... Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent. (a) Agents....

  19. Anticancer agents from marine sponges.

    PubMed

    Ye, Jianjun; Zhou, Feng; Al-Kareef, Ammar M Q; Wang, Hong

    2015-01-01

    Marine sponges are currently one of the richest sources of anticancer active compounds found in the marine ecosystems. More than 5300 different known metabolites are from sponges and their associated microorganisms. To survive in the complicated marine environment, most of the sponge species have evolved chemical means to defend against predation. Such chemical adaptation produces many biologically active secondary metabolites including anticancer agents. This review highlights novel secondary metabolites in sponges which inhibited diverse cancer species in the recent 5 years. These natural products of marine sponges are categorized based on various chemical characteristics.

  20. Detecting biological warfare agents.

    PubMed

    Song, Linan; Ahn, Soohyoun; Walt, David R

    2005-10-01

    We developed a fiber-optic, microsphere-based, high-density array composed of 18 species-specific probe microsensors to identify biological warfare agents. We simultaneously identified multiple biological warfare agents in environmental samples by looking at specific probe responses after hybridization and response patterns of the multiplexed array.

  1. Travel Agent Course Outline.

    ERIC Educational Resources Information Center

    British Columbia Dept. of Education, Victoria.

    Written for college entry-level travel agent training courses, this course outline can also be used for inservice training programs offered by travel agencies. The outline provides information on the work of a travel agent and gives clear statements on what learners must be able to do by the end of their training. Material is divided into eight…

  2. Change Agent Survival Guide

    ERIC Educational Resources Information Center

    Dunbar, Folwell L.

    2011-01-01

    Consulting is a rough racket. Only a tarantula hair above IRS agents, meter maids and used car sales people, the profession is a prickly burr for slings and arrows. Throw in education, focus on dysfunctional schools and call oneself a "change agent," and this bad rap all but disappears. Unfortunately, though, consulting/coaching/mentoring in…

  3. Ferrimagnetic susceptibility contrast agents.

    PubMed

    Bach-Gansmo, T

    1993-01-01

    Contrast agents based on superparamagnetic particles have been in clinical development for more than 5 years, and the complexity of their effects is still not elucidated. The relaxivities are frequently used to give an idea of their efficacy, but these parameters can only be used if they are concentration independent. For large superparamagnetic systems, the evolution of the transverse magnetization is biexponential, after an initial loss of magnetization. Both these characteristics of large superparamagnetic systems should lead to prudence in using the relaxivities as indicators of contrast medium efficacy. Susceptibility induced artefacts have been associated with the use of superparamagnetic contrast agents since the first imaging evaluation took place. The range of concentrations where good contrast effect was achieved without inducing artefacts, as well as blurring and metal artefacts were evaluated. The influence of motion on the induction of artefacts was studied, and compared to the artefacts induced by a paramagnetic agent subject to motion. With a suitable concentration of a negative contrast agent, a signal void could be achieved in the region prone to motion, and no artefacts were induced. If the concentration was too high, a displacement of the region close to the contrast agent was observed. The artefacts occurred in a volume surrounding the contrast agent, i.e., also outside the imaging plane. In comparison a positive, paramagnetic contrast agent induced heavy artefacts in the phase encoding direction, appearing as both high intensity regions and black holes, in a mosaic pattern. Clinical trials of the oral contrast agent OMP for abdominal MR imaging showed this agent to be safe and efficacious. OMP increased the diagnostic efficacy of abdominal MR imaging in 2 of 3 cases examined, with a significant decrease in motion artefacts. Susceptibility contrast agents may also be of use in the evaluation of small lesions in the liver. Particulate material

  4. A user-system interface agent

    NASA Technical Reports Server (NTRS)

    Wakim, Nagi T.; Srivastava, Sadanand; Bousaidi, Mehdi; Goh, Gin-Hua

    1995-01-01

    Agent-based technologies answer to several challenges posed by additional information processing requirements in today's computing environments. In particular, (1) users desire interaction with computing devices in a mode which is similar to that used between people, (2) the efficiency and successful completion of information processing tasks often require a high-level of expertise in complex and multiple domains, (3) information processing tasks often require handling of large volumes of data and, therefore, continuous and endless processing activities. The concept of an agent is an attempt to address these new challenges by introducing information processing environments in which (1) users can communicate with a system in a natural way, (2) an agent is a specialist and a self-learner and, therefore, it qualifies to be trusted to perform tasks independent of the human user, and (3) an agent is an entity that is continuously active performing tasks that are either delegated to it or self-imposed. The work described in this paper focuses on the development of an interface agent for users of a complex information processing environment (IPE). This activity is part of an on-going effort to build a model for developing agent-based information systems. Such systems will be highly applicable to environments which require a high degree of automation, such as, flight control operations and/or processing of large volumes of data in complex domains, such as the EOSDIS environment and other multidisciplinary, scientific data systems. The concept of an agent as an information processing entity is fully described with emphasis on characteristics of special interest to the User-System Interface Agent (USIA). Issues such as agent 'existence' and 'qualification' are discussed in this paper. Based on a definition of an agent and its main characteristics, we propose an architecture for the development of interface agents for users of an IPE that is agent-oriented and whose resources

  5. Standard Agent Framework 1

    1999-04-06

    The Standard Agent framework provides an extensible object-oriented development environment suitable for use in both research and applications projects. The SAF provides a means for constructing and customizing multi-agent systems through specialization of standard base classes (architecture-driven framework) and by composition of component classes (data driven framework). The standard agent system is implemented as an extensible object-centerd framework. Four concrete base classes are developed: (1) Standard Agency; (2) Standard Agent; (3) Human Factor, and (4)more » Resources. The object-centered framework developed and utilized provides the best comprimise between generality and flexibility available in agent development systems today.« less

  6. How do agents represent?

    NASA Astrophysics Data System (ADS)

    Ryan, Alex

    Representation is inherent to the concept of an agent, but its importance in complex systems has not yet been widely recognised. In this paper I introduce Peirce's theory of signs, which facilitates a definition of representation in general. In summary, representation means that for some agent, a model is used to stand in for another entity in a way that shapes the behaviour of the agent with respect to that entity. Representation in general is then related to the theories of representation that have developed within different disciplines. I compare theories of representation from metaphysics, military theory and systems theory. Additional complications arise in explaining the special case of mental representations, which is the focus of cognitive science. I consider the dominant theory of cognition — that the brain is a representational device — as well as the sceptical anti-representational response. Finally, I argue that representation distinguishes agents from non-representational objects: agents are objects capable of representation.

  7. Chelating agents and cadmium intoxication

    SciTech Connect

    Shinobu, L.A.

    1985-01-01

    A wide range of conventional chelating agents have been screened for (a) antidotal activity in acute cadmium poisoning and (b) ability to reduce aged liver and kidney deposits of cadmium. Chelating agents belonging to the dithiocarbamate class have been synthesized and tested in both the acute and chronic modes of cadmium intoxication. Several dithiocarbamates, not only provide antidotal rescue, but also substantially decrease the intracellular deposits of cadmium associated with chronic cadmium intoxication. Fractionating the cytosol from the livers and kidneys of control and treated animals by Sephadex G-25 gel filtration clearly demonstrates that the dithiocarbamates are reducing the level of metallothionein-bound cadmium. However, the results of cell culture (Ehrlich ascites) studies designed to investigate the removal of cadmium from metallothionein and subsequent transport of the resultant cadmium complex across the cell membrane were inconclusive. In other in vitro investigations, the interaction between isolated native Cd, Zn-metallothionein and several chelating agents was explored. Ultracentrifugation, equilibrium dialysis, and Sephadex G-25 gel filtration studies have been carried out in an attempt to determine the rate of removal of cadmium from metallothionein by these small molecules. Chemical shifts for the relevant cadmium-dithiocarbamate complexes have been determined using natural abundance Cd-NMR.

  8. Biological warfare agents.

    PubMed

    Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan

    2010-07-01

    The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  9. Biological warfare agents

    PubMed Central

    Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan

    2010-01-01

    The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies. PMID:21829313

  10. Chemopreventive agents targeting tumor microenvironment.

    PubMed

    Sharma, Sharada H; Thulasingam, Senthilkumar; Nagarajan, Sangeetha

    2016-01-15

    Recent studies have shown that tumor development and progression depend not only on the perturbed genes that govern cell proliferation, but is also highly determined by the non-tumor cells of the stromal compartment surrounding the tumor called tumor microenvironment (TME). These findings highlight the importance of targeting the microenvironment in combination with therapies aimed at tumor cells as a valuable approach. The innate and adaptive immune cells in the TME interact among themselves and also with the endothelial cells, pericytes and mast cells of the stromal compartment through various autocrine and paracrine manner to regulate abnormal cell proliferation. Direct cytotoxic killing of cancer cells and/or reversion of the immunosuppressive TME are to be considered as better strategies for chemoprevention and chemotherapy. With a growing emphasis on a "hallmark targeting" strategy for cancer therapy, the TME now appears as a promising target for cancer prevention using natural products. Clarification on the nontumor stromal cells, the mediators involved, interactions with immune response cells, and immune-evasive mechanisms are needed in order to manipulate the characteristics of the TME by natural pharmacological agents to design effective therapies. This review will provide a glimpse on the roles played by various non-tumor cells in tumor progression and their intervention by pharmacological agents. PMID:26679106

  11. Dioxin, agent orange

    SciTech Connect

    Gough, M.

    1986-01-01

    This book presents information on the following topics: dioxin, a prevalent problem; nobody wanted dioxin; agent organe and Vietnam; what we know about and may learn about agent orange and Veterans' health; agent organe and birth defects; dioxin in Missouri; 2, 4, 5-T: the U.S.' disappearing herbicide; Seveso: high-level environmental exposure; the nitro explosion; industrial exposures to dioxin; company behavior in the face of dioxin exposures; dioxin and specific cancers; animal tests of dioxin toxicity; dioxin decions; the present and the future.

  12. The threat of mid-spectrum chemical warfare agents.

    PubMed

    Aas, Pål

    2003-01-01

    There is a spectrum of several threat agents, ranging from nerve agents and mustard agents to natural substances, such as biotoxins and new, synthetic, bioactive molecules produced by the chemical industry, to the classical biological warfare agents. The new, emerging threat agents are biotoxins produced by animals, plants, fungi, and bacteria. Examples of such biotoxins are botulinum toxin, tetanus toxin, and ricin. Several bioactive molecules produced by the pharmaceutical industry can be even more toxic than are the classical chemical warfare agents. Such new agents, like the biotoxins and bioregulators, often are called mid-spectrum agents. The threat to humans from agents developed by modern chemical synthesis and by genetic engineering also must be considered, since such agents may be more toxic or more effective in causing death or incapacitation than classical warfare agents. By developing effective medical protection and treatment against the most likely chemical and mid-spectrum threat agents, the effects of such agents in a war scenario or following a terrorist attack can be reduced.

  13. The Respiratory Toxicity of Chemical Warefare Agents

    EPA Science Inventory

    Inhalation is one of the most important routes of exposure for chemical warfare agents (CWAs) and thus, the lung remains a critical target of injury. Depending on the mode of action by which the CWAs cause injury, the nature of injury, the location being impacted within the respi...

  14. Riot Control Agents

    MedlinePlus

    ... your clothing, rapidly wash your entire body with soap and water, and get medical care as quickly ... agent from your skin with large amounts of soap and water. Washing with soap and water will ...

  15. Radioactive diagnostic agent

    SciTech Connect

    Shigematsu, A.; Aihara, M.; Matsuda, M.; Suzuki, A.; Tsuya, A.

    1984-02-07

    A radioactive diagnostic agent for renal cortex, adrenal cortex, myocardium, brain stem, spinal nerve, etc., which comprises as an essential component monoiodoacetic acid wherein the iodine atom is radioactive.

  16. Agent oriented programming

    NASA Technical Reports Server (NTRS)

    Shoham, Yoav

    1994-01-01

    The goal of our research is a methodology for creating robust software in distributed and dynamic environments. The approach taken is to endow software objects with explicit information about one another, to have them interact through a commitment mechanism, and to equip them with a speech-acty communication language. System-level applications include software interoperation and compositionality. A government application of specific interest is an infrastructure for coordination among multiple planners. Daily activity applications include personal software assistants, such as programmable email, scheduling, and new group agents. Research topics include definition of mental state of agents, design of agent languages as well as interpreters for those languages, and mechanisms for coordination within agent societies such as artificial social laws and conventions.

  17. Agent amplified communication

    SciTech Connect

    Kautz, H.; Selman, B.; Milewski, A.

    1996-12-31

    We propose an agent-based framework for assisting and simplifying person-to-person communication for information gathering tasks. As an example, we focus on locating experts for any specified topic. In our approach, the informal person-to-person networks that exist within an organization are used to {open_quotes}referral chain{close_quotes} requests for expertise. User-agents help automate this process. The agents generate referrals by analyzing records of e-mail communication patterns. Simulation results show that the higher responsiveness of an agent-based system can be effectively traded for the higher accuracy of a completely manual approach. Furthermore, preliminary experience with a group of users on a prototype system has shown that useful automatic referrals can be found in practice. Our experience with actual users has also shown that privacy concerns are central to the successful deployment of personal agents: an advanced agent-based system will therefore need to reason about issues involving trust and authority.

  18. [Decontamination of chemical and biological warfare agents].

    PubMed

    Seto, Yasuo

    2009-01-01

    Chemical and biological warfare agents (CBWA's) are diverse in nature; volatile acute low-molecular-weight toxic compounds, chemical warfare agents (CWA's, gaseous choking and blood agents, volatile nerve gases and blister agents, nonvolatile vomit agents and lacrymators), biological toxins (nonvolatile low-molecular-weight toxins, proteinous toxins) and microbes (bacteria, viruses, rickettsiae). In the consequence management against chemical and biological terrorism, speedy decontamination of victims, facilities and equipment is required for the minimization of the damage. In the present situation, washing victims and contaminated materials with large volumes of water is the basic way, and additionally hypochlorite salt solution is used for decomposition of CWA's. However, it still remains unsolved how to dispose large volumes of waste water, and the decontamination reagents have serious limitation of high toxicity, despoiling nature against the environments, long finishing time and non-durability in effective decontamination. Namely, the existing decontamination system is not effective, nonspecifically affecting the surrounding non-target materials. Therefore, it is the urgent matter to build up the usable decontamination system surpassing the present technologies. The symposiast presents the on-going joint project of research and development of the novel decontamination system against CBWA's, in the purpose of realizing nontoxic, fast, specific, effective and economical terrorism on-site decontamination. The projects consists of (1) establishment of the decontamination evaluation methods and verification of the existing technologies and adaptation of bacterial organophosphorus hydrolase, (2) development of adsorptive elimination technologies using molecular recognition tools, and (4) development of deactivation technologies using photocatalysis. PMID:19122437

  19. [Decontamination of chemical and biological warfare agents].

    PubMed

    Seto, Yasuo

    2009-01-01

    Chemical and biological warfare agents (CBWA's) are diverse in nature; volatile acute low-molecular-weight toxic compounds, chemical warfare agents (CWA's, gaseous choking and blood agents, volatile nerve gases and blister agents, nonvolatile vomit agents and lacrymators), biological toxins (nonvolatile low-molecular-weight toxins, proteinous toxins) and microbes (bacteria, viruses, rickettsiae). In the consequence management against chemical and biological terrorism, speedy decontamination of victims, facilities and equipment is required for the minimization of the damage. In the present situation, washing victims and contaminated materials with large volumes of water is the basic way, and additionally hypochlorite salt solution is used for decomposition of CWA's. However, it still remains unsolved how to dispose large volumes of waste water, and the decontamination reagents have serious limitation of high toxicity, despoiling nature against the environments, long finishing time and non-durability in effective decontamination. Namely, the existing decontamination system is not effective, nonspecifically affecting the surrounding non-target materials. Therefore, it is the urgent matter to build up the usable decontamination system surpassing the present technologies. The symposiast presents the on-going joint project of research and development of the novel decontamination system against CBWA's, in the purpose of realizing nontoxic, fast, specific, effective and economical terrorism on-site decontamination. The projects consists of (1) establishment of the decontamination evaluation methods and verification of the existing technologies and adaptation of bacterial organophosphorus hydrolase, (2) development of adsorptive elimination technologies using molecular recognition tools, and (4) development of deactivation technologies using photocatalysis.

  20. 12 CFR 709.2 - NCUA Board as liquidating agent.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 7 2012-01-01 2012-01-01 false NCUA Board as liquidating agent. 709.2 Section... INSURED CREDIT UNIONS IN LIQUIDATION § 709.2 NCUA Board as liquidating agent. (a) The Board, as... connection with any assets or property of any nature of the credit union. (b) The Board, as liquidating...

  1. Agent independent task planning

    NASA Technical Reports Server (NTRS)

    Davis, William S.

    1990-01-01

    Agent-Independent Planning is a technique that allows the construction of activity plans without regard to the agent that will perform them. Once generated, a plan is then validated and translated into instructions for a particular agent, whether a robot, crewmember, or software-based control system. Because Space Station Freedom (SSF) is planned for orbital operations for approximately thirty years, it will almost certainly experience numerous enhancements and upgrades, including upgrades in robotic manipulators. Agent-Independent Planning provides the capability to construct plans for SSF operations, independent of specific robotic systems, by combining techniques of object oriented modeling, nonlinear planning and temporal logic. Since a plan is validated using the physical and functional models of a particular agent, new robotic systems can be developed and integrated with existing operations in a robust manner. This technique also provides the capability to generate plans for crewmembers with varying skill levels, and later apply these same plans to more sophisticated robotic manipulators made available by evolutions in technology.

  2. Sunscreening agents: a review.

    PubMed

    Latha, M S; Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B R

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents.

  3. Intelligent agents for e-commerce applications

    NASA Astrophysics Data System (ADS)

    Vuppala, Krishna

    1999-12-01

    This thesis focuses on development of intelligent agent solutions for e-commerce applications. E-Commerce has several complexities like: lack of information about the players, learning the nature of one's business partners/competitors, finding the right business partner to do business with, using the right strategy to get best profit out of the negotiations etc. The agent models developed can be used in any agent solution for e-commerce. Concepts and techniques from Game Theory and Artificial Intelligence are used. The developed models have several advantages over the existing ones as: the models assume the non-availability of information about other players in the market, the models of players get updated over the time as and when new information comes about the players, the negotiation model incorporates the patience levels of the players and expectations from other players in the market. Power industry has been chosen as the application area for the demonstration of the capabilities and usage of the developed agent models. Two e-commerce scenarios where sellers and buyers can go through the power exchanges to bid in auctions, or make bilateral deals outside of the exchange are addressed. In the first scenario agent helps market participants in coordinating strategies with other participants, bidding in auctions by analyzing and understanding the behavior of other participants. In the second scenario, called "Power Traders Assistant" agent helps power trader, who buys and sells power through bilateral negotiations, in negotiating deals with his customers.

  4. Agent-Based Modeling of Growth Processes

    ERIC Educational Resources Information Center

    Abraham, Ralph

    2014-01-01

    Growth processes abound in nature, and are frequently the target of modeling exercises in the sciences. In this article we illustrate an agent-based approach to modeling, in the case of a single example from the social sciences: bullying.

  5. Honey - A Novel Antidiabetic Agent

    PubMed Central

    Erejuwa, Omotayo O.; Sulaiman, Siti A.; Wahab, Mohd S. Ab

    2012-01-01

    Diabetes mellitus remains a burden worldwide in spite of the availability of numerous antidiabetic drugs. Honey is a natural substance produced by bees from nectar. Several evidence-based health benefits have been ascribed to honey in the recent years. In this review article, we highlight findings which demonstrate the beneficial or potential effects of honey in the gastrointestinal tract (GIT), on the gut microbiota, in the liver, in the pancreas and how these effects could improve glycemic control and metabolic derangements. In healthy subjects or patients with impaired glucose tolerance or diabetes mellitus, various studies revealed that honey reduced blood glucose or was more tolerable than most common sugars or sweeteners. Pre-clinical studies provided more convincing evidence in support of honey as a potential antidiabetic agent than clinical studies did. The not-too-impressive clinical data could mainly be attributed to poor study designs or due to the fact that the clinical studies were preliminary. Based on the key constituents of honey, the possible mechanisms of action of antidiabetic effect of honey are proposed. The paper also highlights the potential impacts and future perspectives on the use of honey as an antidiabetic agent. It makes recommendations for further clinical studies on the potential antidiabetic effect of honey. This review provides insight on the potential use of honey, especially as a complementary agent, in the management of diabetes mellitus. Hence, it is very important to have well-designed, randomized controlled clinical trials that investigate the reproducibility (or otherwise) of these experimental data in diabetic human subjects. PMID:22811614

  6. MpcAgent

    2013-11-29

    MpcAgent software is a module for the VolltronLite platform from PNNL that regulates the operation of rooftop air conditioning units in small to medium commercial buildings for the purpose of reducing peak power consumption. The MpcAgent accomplishes this by restricting the number of units that may operate simultaneously and using a model predictive control strategy to select which units to operate in each control period. The outcome of this control is effective control of themore » building air temperature at the user specified set point while avoiding expensive peak demand charges that result from running all HVAC units simultaneously.« less

  7. MpcAgent

    SciTech Connect

    Nutaro, James

    2013-11-29

    MpcAgent software is a module for the VolltronLite platform from PNNL that regulates the operation of rooftop air conditioning units in small to medium commercial buildings for the purpose of reducing peak power consumption. The MpcAgent accomplishes this by restricting the number of units that may operate simultaneously and using a model predictive control strategy to select which units to operate in each control period. The outcome of this control is effective control of the building air temperature at the user specified set point while avoiding expensive peak demand charges that result from running all HVAC units simultaneously.

  8. Agent Persuasion Mechanism of Acquaintance

    NASA Astrophysics Data System (ADS)

    Jinghua, Wu; Wenguang, Lu; Hailiang, Meng

    Agent persuasion can improve negotiation efficiency in dynamic environment based on its initiative and autonomy, and etc., which is being affected much more by acquaintance. Classification of acquaintance on agent persuasion is illustrated, and the agent persuasion model of acquaintance is also illustrated. Then the concept of agent persuasion degree of acquaintance is given. Finally, relative interactive mechanism is elaborated.

  9. 13 CFR 108.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent. 108.1620 Section 108.1620 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM SBA...

  10. Battlefield agent collaboration

    NASA Astrophysics Data System (ADS)

    Budulas, Peter P.; Young, Stuart H.; Emmerman, Philip J.

    2001-09-01

    Small air and ground physical agents (robots) will be ubiquitous on the battlefield of the 21st century, principally to lower the exposure to harm of our ground forces in urban and open terrain scenarios. Teams of small collaborating physical agents conducting tasks such as Reconnaissance, Surveillance, and Target Acquisition (RSTA), intelligence, chemical and biological agent detection, logistics, decoy, sentry; and communications relay will have advanced sensors, communications, and mobility characteristics. It is anticipated that there will be many levels of individual and team collaboration between the soldier and robot, robot to robot, and robot to mother ship. This paper presents applications and infrastructure components that illustrate each of these levels. As an example, consider the application where a team of twenty small robots must rapidly explore and define a building complex. Local interactions and decisions require peer to peer collaboration. Global direction and information fusion warrant a central team control provided by a mother ship. The mother ship must effectively deliver/retrieve, service, and control these robots as well as fuse the information gathered by these highly mobile robot teams. Any level of collaboration requires robust communications, specifically a mobile ad hoc network. The application of fixed ground sensors and mobile robots is also included in this paper. This paper discusses on going research at the U.S. Army Research Laboratory that supports the development of multi-robot collaboration. This research includes battlefield visualization, intelligent software agents, adaptive communications, sensor and information fusion, and multi-modal human computer interaction.

  11. Mobility control agent

    SciTech Connect

    Argabright, P.A.; Phillips, B.L.; Rhudy, J.S.

    1983-05-17

    Polymer mobility control agents useful in supplemental oil recovery processes, which give improved reciprocal relative mobilities, are prepared by initiating the polymerization of a monomer containing a vinyl group with a catalyst comprising a persulfate and ferrous ammonium sulfate. The vinyl monomer is an acrylyl, a vinyl cyanide, a styryl and water soluble salts thereof.

  12. E-Learning Agents

    ERIC Educational Resources Information Center

    Gregg, Dawn G.

    2007-01-01

    Purpose: The purpose of this paper is to illustrate the advantages of using intelligent agents to facilitate the location and customization of appropriate e-learning resources and to foster collaboration in e-learning environments. Design/methodology/approach: This paper proposes an e-learning environment that can be used to provide customized…

  13. Remote Agent Experiment

    NASA Technical Reports Server (NTRS)

    Benard, Doug; Dorais, Gregory A.; Gamble, Ed; Kanefsky, Bob; Kurien, James; Millar, William; Muscettola, Nicola; Nayak, Pandu; Rouquette, Nicolas; Rajan, Kanna; Norvig, Peter (Technical Monitor)

    2000-01-01

    Remote Agent (RA) is a model-based, reusable artificial intelligence (At) software system that enables goal-based spacecraft commanding and robust fault recovery. RA was flight validated during an experiment on board of DS1 between May 17th and May 21th, 1999.

  14. Can Subscription Agents Survive?

    ERIC Educational Resources Information Center

    Tuttle, Marcia

    1985-01-01

    With the saturation of traditional markets for their services, subscription agents have evolved from orders and invoices to serving customers by communicating with librarians and publishers and making automated and paper products available. Magazine fulfillment centers, publisher discounts, and electronic publishing will influence the subscription…

  15. Learning Sequences of Actions in Collectives of Autonomous Agents

    NASA Technical Reports Server (NTRS)

    Turner, Kagan; Agogino, Adrian K.; Wolpert, David H.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    In this paper we focus on the problem of designing a collective of autonomous agents that individually learn sequences of actions such that the resultant sequence of joint actions achieves a predetermined global objective. We are particularly interested in instances of this problem where centralized control is either impossible or impractical. For single agent systems in similar domains, machine learning methods (e.g., reinforcement learners) have been successfully used. However, applying such solutions directly to multi-agent systems often proves problematic, as agents may work at cross-purposes, or have difficulty in evaluating their contribution to achievement of the global objective, or both. Accordingly, the crucial design step in multiagent systems centers on determining the private objectives of each agent so that as the agents strive for those objectives, the system reaches a good global solution. In this work we consider a version of this problem involving multiple autonomous agents in a grid world. We use concepts from collective intelligence to design goals for the agents that are 'aligned' with the global goal, and are 'learnable' in that agents can readily see how their behavior affects their utility. We show that reinforcement learning agents using those goals outperform both 'natural' extensions of single agent algorithms and global reinforcement, learning solutions based on 'team games'.

  16. Towards an agent-oriented programming language based on Scala

    NASA Astrophysics Data System (ADS)

    Mitrović, Dejan; Ivanović, Mirjana; Budimac, Zoran

    2012-09-01

    Scala and its multi-threaded model based on actors represent an excellent framework for developing purely reactive agents. This paper presents an early research on extending Scala with declarative programming constructs, which would result in a new agent-oriented programming language suitable for developing more advanced, BDI agent architectures. The main advantage the new language over many other existing solutions for programming BDI agents is a natural and straightforward integration of imperative and declarative programming constructs, fitted under a single development framework.

  17. Smell Detection Agent Based Optimization Algorithm

    NASA Astrophysics Data System (ADS)

    Vinod Chandra, S. S.

    2016-09-01

    In this paper, a novel nature-inspired optimization algorithm has been employed and the trained behaviour of dogs in detecting smell trails is adapted into computational agents for problem solving. The algorithm involves creation of a surface with smell trails and subsequent iteration of the agents in resolving a path. This algorithm can be applied in different computational constraints that incorporate path-based problems. Implementation of the algorithm can be treated as a shortest path problem for a variety of datasets. The simulated agents have been used to evolve the shortest path between two nodes in a graph. This algorithm is useful to solve NP-hard problems that are related to path discovery. This algorithm is also useful to solve many practical optimization problems. The extensive derivation of the algorithm can be enabled to solve shortest path problems.

  18. Measure Landscape Diversity with Logical Scout Agents

    NASA Astrophysics Data System (ADS)

    Wirth, E.; Szabó, G.; Czinkóczky, A.

    2016-06-01

    The Common Agricultural Policy reform of the EU focuses on three long-term objectives: viable food production, sustainable management of natural resources and climate action with balanced territorial development. To achieve these goals, the EU farming and subsidizing policies (EEA, 2014) support landscape heterogeneity and diversity. Current paper introduces an agent-based method to calculate the potential of landscape diversity. The method tries to catch the nature of heterogeneity using logic and modelling as opposed to the traditional statistical reasoning. The outlined Random Walk Scouting algorithm registers the land cover crossings of the scout agents to a Monte Carlo integral. The potential is proportional with the composition and the configuration (spatial character) of the landscape. Based on the measured points a potential map is derived to give an objective and quantitative basis to the stakeholders (policy makers, farmers).

  19. An Extension Dynamic Model Based on BDI Agent

    NASA Astrophysics Data System (ADS)

    Yu, Wang; Feng, Zhu; Hua, Geng; WangJing, Zhu

    this paper's researching is based on the model of BDI Agent. Firstly, This paper analyze the deficiencies of the traditional BDI Agent model, Then propose an extension dynamic model of BDI Agent based on the traditional ones. It can quickly achieve the internal interaction of the tradition model of BDI Agent, deal with complex issues under dynamic and open environment and achieve quick reaction of the model. The new model is a natural and reasonable model by verifying the origin of civilization using the model of monkeys to eat sweet potato based on the design of the extension dynamic model. It is verified to be feasible by comparing the extended dynamic BDI Agent model with the traditional BDI Agent Model uses the SWARM, it has important theoretical significance.

  20. Induction of S-Phase Arrest in Human Glioma Cells by Selenocysteine, a Natural Selenium-Containing Agent Via Triggering Reactive Oxygen Species-Mediated DNA Damage and Modulating MAPKs and AKT Pathways.

    PubMed

    Wang, Kun; Fu, Xiao-Ting; Li, Yuan; Hou, Ya-Jun; Yang, Ming-Feng; Sun, Jing-Yi; Yi, Shu-Ying; Fan, Cun-Dong; Fu, Xiao-Yan; Zhai, Jing; Sun, Bao-Liang

    2016-06-01

    Selenocysteine (SeC) a natural available selenoamino acid exhibits novel anticancer activities against human cancer cell lines. However, the growth inhibitory effect and mechanism of SeC in human glioma cells remain unclear. The present study reveals that SeC time- and dose-dependently inhibited U251 and U87 human glioma cells growth by induction of S-phase cell cycle arrest, followed by the marked decrease of cyclin A. SeC-induced S-phase arrest was achieved by inducing DNA damage through triggering generation of reactive oxygen species (ROS) and superoxide anion, with concomitant increase of TUNEL-positive cells and induction of p21waf1/Cip1 and p53. SeC treatment also caused the activation of p38MAPK, JNK and ERK, and inactivation of AKT. Four inhibitors of MAPKs and AKT pathways further confirmed their roles in SeC-induced S-phase arrest in human glioma cells. Our findings advance the understanding on the molecular mechanisms of SeC in human glioma management. PMID:26846141

  1. Screening of anti-hypoxia/reoxygenation agents by an in vitro model. Part 1: Natural inhibitors for protein tyrosine kinase activated by hypoxia/reoxygenation in cultured human umbilical vein endothelial cells.

    PubMed

    Zhang, Y W; Morita, I; Shao, G; Yao, X S; Murota, S

    2000-03-01

    Protein tyrosine kinase (PTK) signaling pathways play important roles in ischemia/reperfusion (I/R) or hypoxia/reoxygenation (H/R) injuries. Inhibition of PTK activation can protect against I/R- or H/R-induced damages. As one part of our work for seeking bioactive compounds from natural sources against I/R or H/R, in the present study we examined the effects of 54 compounds purified from various traditional Chinese herbs on H/R-induced PTK activation by means of an in vitro H/R model in cultured human umbilical vein endothelial cells (HUVEC). The results demonstrated that an increase in PTK activation was induced after 2 h of reoxygenation. Compounds 2 (macrostemososide A), 3 (laxogenin-3-O-beta-D-xylopyranosyl-(1-->4)-alpha-L-arabinopyra nosyl- (1-->6)-beta-D-glucopyranoside), 4 (chinenoside II), 7 (ginsenoside-Rd), 52 (icariin), 53 (icariside), and 54 (icaritin) showed relatively obvious inhibition on this H/R-induced PTK activation. Compounds 5 (beta-sitosterol) and 6 (daucosterine), especially 5, completely blocked such an increased activation of PTK induced by H/R. On the contrary, compound 29 (isocumarine) significantly promoted PTK activation further. Moreover, the effects of these compounds on PTK activation were dose-dependent. PMID:10763582

  2. Emulsified blasting agents

    SciTech Connect

    Chironis, N.P.

    1985-01-01

    This article describes an improved blasting agent which is being tailor-blended with bulk ANFO to provide more explosive energy and better water resistance when the blasting conditions call for it. The proportions of the emulsion/ANFO mix are easily changed at the blasthole site because both materials can be selectively mixed in modified bulk-explosive trucks before loading the blasting agents into the holes. Such blends are helping speed stripping at a number of surface mines and are leading to cost savings in production, ranging from 10% to 30%, depending upon application, even though the actual cost of a blend will be higher than if bulk ANFO is used alone.

  3. The unofficial vasectomy agent of East Pakistan. (Bangladesh).

    PubMed

    Quddus, A H; Ratcliffe, J W; Croley, H T

    1969-01-01

    This study was undertaken to inquire into the background of individuals known as "vasectomy agents." They act by bringing men into the East Pakistan (Bangladesh) Family Planning Clinics for vasectomy. Their activities have caused the number of vasectomies to rise beyond expectation. Although voluntary at first, they have recently been paid a fee for such services. Many also receive commissions from doctors or others. A total of 155 such agents were interviewed at 24 clinics in 3 districts of East Pakistan. 32 of the agents were women. The median age of all agents was 37.3 years. Of the 155 agents, 60% were engaged full-time in recruiting men for vasectomies. Some had brought in over 100 clients. Of the part-time agents, 37% were farmers, 31% in business, 22% in service employment, and 12% were day laborers. Of the 123 male agents, about 40% had undergone vasectomy themselves. Most agents were from low income groups. Their incomes from acting as agents had increased slightly. About 80% reported acting as agents for 1 year or less. Adequate information about the vasectomy operation seems to have been communicated to clients by the agents. The majority of clients had been concerned about the nature and implications of the vasectomy operation, particularly regarding the loss of sexual potency and their ability to continue working. Many agents encountered opposition from the general public and religious and village leaders. Negative rumors were circulated about the method. Since these agents have made a major contribution to the vasectomy program in East Pakistan, it is thought that they should be given official recognition. By registration, recruiting activities could be supervised. Improved monetary incentives would attract more and better persons. A training course, given by clinic physicians is recommended. In this way agents would be subject to evaluation by an interested and competent person. PMID:12305304

  4. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, Mark P.; Mease, Ronnie C.; Srivastava, Suresh C.

    2000-02-08

    Bicyclo[2.2.2]octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo[2.2.1]heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  5. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, M.P.; Mease, R.C.; Srivastava, S.C.

    1998-07-21

    Bicyclo[2.2.2] octane-2,3 diamine-N,N,N`,N`-tetraacetic acids (BODTA) and bicyclo[2.2.1] heptane-2,3 diamine-N,N,N`,N`-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  6. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, Mark P.; Mease, Ronnie C.; Srivastava, Suresh C.

    1998-07-21

    Bicyclo›2.2.2! octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo›2.2.1! heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  7. Surface polymerization agents

    SciTech Connect

    Taylor, C.; Wilkerson, C.

    1996-12-01

    This is the final report of a 1-year, Laboratory-Directed R&D project at LANL. A joint technical demonstration was proposed between US Army Missile Command (Redstone Arsenal) and LANL. Objective was to demonstrate that an unmanned vehicle or missile could be used as a platform to deliver a surface polymerization agent in such a manner as to obstruct the filters of an air-breathing mechanism, resulting in operational failure.

  8. [Naturalizing empathy].

    PubMed

    Decety, J

    2002-01-01

    Empathy is the ability to share emotions with others. It is acknowledged to be a powerful means of tacit communication, a key ingredient in any therapeutic relationship as well as in psychotherapy. Empathy is the cornerstone in the humanist perspective (Ego-psychology) in clinical psychology. This approach is often considered as poorly grounded on scientific and objective evidence. It is however acknowledged that empathetic therapists are more effective than less empathetic therapists. I shall argue that this paradox, i.e. it is the least scientific and the less validated psychotherapeutic approach that is the most efficient, can be eliminated if one considers the nature of empathy, its biological foundation, its evolutionary origin and its cognitive architecture. In this paper I will suggest that empathy is based on specific information processing modules which have been designed by natural selection to cope with social regularities in expressing and reading emotional states. This has provided adaptive benefits to individuals living in large groups bestowing them with mechanisms for cooperativity, altruism and more generally various aspects of prosocial behaviour. The capacity to express emotions, and to read and understand emotions of others also ensures implicit communication with others and may be at the root of intersubjectivity. This perspective on empathy is then articulated with two concurrent hypotheses regarding theory of mind (the simulation and the theory-theory) which aim to explain the human capacity to understand that the behaviors of other intelligent agents are caused by intentions, desires and beliefs. In this context, empathy can be considered as a simulation (or analogical) process that is necessary to understand but not sufficient to interpret other people. This last issue is relevant to clinical practice. PMID:11963348

  9. A STUDY OF NORTH CAROLINA AGRICULTURAL EXTENSION AGENTS' PERCEPTION OF THE ROLE OF FERTILIZER DEALERS IN EXTENSION PROGRAMMING.

    ERIC Educational Resources Information Center

    WOODARD, BRUCE H.

    A QUESTIONNAIRE MAILED TO 98 AGRICULTURAL EXTENSION AGENTS IN NORTH CAROLINA WITH PRIMARY RESPONSIBILITY IN AGRONOMY IN THEIR COUNTIES WAS USED TO COLLECT DATA ON THE AGENTS' PERCEPTION OF THE NATURE AND FREQUENCY OF PERFORMANCE BY DEALERS IN SOIL FERTILITY PROGRAMS, AGENTS' FEELINGS ABOUT DEALER PARTICIPATION, AND THE ASSOCIATION BETWEEN AGENTS'…

  10. Hydroxypyridonate and hydroxypyrimidinone chelating agents

    DOEpatents

    Raymond, Kenneth N.; Doble, Daniel M.; Sunderland, Christopher J.; Thompson, Marlon

    2005-01-25

    The present invention provides hydroxypyridinone and hydroxypyrimidone chelating agents. Also provides are Gd(III) complexes of these agents, which are useful as contrast enhancing agents for magnetic resonance imaging. The invention also provides methods of preparing the compounds of the invention, as well as methods of using the compounds in magnetic resonance imaging applications.

  11. Chemical warfare agents

    PubMed Central

    Ganesan, K.; Raza, S. K.; Vijayaraghavan, R.

    2010-01-01

    Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided. PMID:21829312

  12. Holograms as Teaching Agents

    NASA Astrophysics Data System (ADS)

    Walker, Robin A.

    2013-02-01

    Hungarian physicist Dennis Gabor won the Pulitzer Prize for his 1947 introduction of basic holographic principles, but it was not until the invention of the laser in 1960 that research scientists, physicians, technologists and the general public began to seriously consider the interdisciplinary potentiality of holography. Questions around whether and when Three-Dimensional (3-D) images and systems would impact American entertainment and the arts would be answered before educators, instructional designers and students would discover how much Three-Dimensional Hologram Technology (3DHT) would affect teaching practices and learning environments. In the following International Symposium on Display Holograms (ISDH) poster presentation, the author features a traditional board game as well as a reflection hologram to illustrate conventional and evolving Three-Dimensional representations and technology for education. Using elements from the American children's toy Operation® (Hasbro, 2005) as well as a reflection hologram of a human brain (Ko, 1998), this poster design highlights the pedagogical effects of 3-D images, games and systems on learning science. As teaching agents, holograms can be considered substitutes for real objects, (human beings, organs, and animated characters) as well as agents (pedagogical, avatars, reflective) in various learning environments using many systems (direct, emergent, augmented reality) and electronic tools (cellphones, computers, tablets, television). In order to understand the particular importance of utilizing holography in school, clinical and public settings, the author identifies advantages and benefits of using 3-D images and technology as instructional tools.

  13. Lipid-lowering agents.

    PubMed

    Ewang-Emukowhate, Mfon; Wierzbicki, Anthony S

    2013-09-01

    The role of lipid lowering in reducing the risk of mortality and morbidity from cardiovascular disease (CVD) is well established. Treatment particularly aimed at decreasing low-density lipoprotein cholesterol (LDL-C) is effective in reducing the risk of death from coronary heart disease and stroke. Statins form the cornerstone of treatment. However, in some individuals with a high risk of CVD who are unable to achieve their target LDL-C due to either intolerance or lack of efficacy, there is the need for alternative therapies. This review provides an overview of the different classes of currently available lipid-lowering medications including statins, fibrates, bile acid sequestrants (resins), and omega-3 fatty acids. Data are presented on their indications, pharmacology, and the relevant end point clinical trial data with these drugs. It also discusses the human trial data on some novel therapeutic agents that are being developed including those for homozygous familial hypercholesterolemia--the antisense oligonucleotide mipomersen and the microsomal transfer protein inhibitor lomitapide. Data are presented on phase II and III trials on agents with potentially wider applications, cholesterol ester transfer protein inhibitors and proprotein convertase subtilisin kexin 9 inhibitors. The data on a licensed gene therapy for lipoprotein lipase deficiency are also presented. PMID:23811423

  14. [Bacteriophages as antibacterial agents].

    PubMed

    Shasha, Shaul M; Sharon, Nehama; Inbar, Michael

    2004-02-01

    Bacteriophages are viruses that only infect bacteria. They have played an important role in the development of molecular biology and have been used as anti-bacterial agents. Since their independent discovery by Twort and d'Herelle, they have been extensively used to prevent and treat bacterial infections, mainly in Eastern Europe and the former Soviet Union. In western countries this method has been sporadically employed on humans and domesticated animals. However, the discovery and widespread use of antibiotics, coupled with doubts about the efficacy of phage therapy, led to an eclipse in the use of phage in medicine. The emergence of antibiotic resistant bacteria, especially strains that are multiply resistant, has resulted in a renewed interest in alternatives to conventional drugs. One of the possible replacements for antibiotics is the use of bacteriophages as antimicrobial agents. This brief review aims to describe the history of bacteriophage and early clinical studies on their use in bacterial disease prophylaxis and therapy, and discuss the advantages and disadvantages of bacteriophage in this regard.

  15. Lipid-lowering agents.

    PubMed

    Ewang-Emukowhate, Mfon; Wierzbicki, Anthony S

    2013-09-01

    The role of lipid lowering in reducing the risk of mortality and morbidity from cardiovascular disease (CVD) is well established. Treatment particularly aimed at decreasing low-density lipoprotein cholesterol (LDL-C) is effective in reducing the risk of death from coronary heart disease and stroke. Statins form the cornerstone of treatment. However, in some individuals with a high risk of CVD who are unable to achieve their target LDL-C due to either intolerance or lack of efficacy, there is the need for alternative therapies. This review provides an overview of the different classes of currently available lipid-lowering medications including statins, fibrates, bile acid sequestrants (resins), and omega-3 fatty acids. Data are presented on their indications, pharmacology, and the relevant end point clinical trial data with these drugs. It also discusses the human trial data on some novel therapeutic agents that are being developed including those for homozygous familial hypercholesterolemia--the antisense oligonucleotide mipomersen and the microsomal transfer protein inhibitor lomitapide. Data are presented on phase II and III trials on agents with potentially wider applications, cholesterol ester transfer protein inhibitors and proprotein convertase subtilisin kexin 9 inhibitors. The data on a licensed gene therapy for lipoprotein lipase deficiency are also presented.

  16. [New agents for hypercholesterolemia].

    PubMed

    Pintó, Xavier; García Gómez, María Carmen

    2016-02-19

    An elevated proportion of high cardiovascular risk patients do not achieve the therapeutic c-LDL goals. This owes to physicians' inappropriate or insufficient use of cholesterol lowering medications or to patients' bad tolerance or therapeutic compliance. Another cause is an insufficient efficacy of current cholesterol lowering drugs including statins and ezetimibe. In addition, proprotein convertase subtilisin kexin type 9 inhibitors are a new cholesterol lowering medications showing safety and high efficacy to reduce c-LDL in numerous already performed or underway clinical trials, potentially allowing an optimal control of hypercholesterolemia in most patients. Agents inhibiting apolipoprotein B synthesis and microsomal transfer protein are also providing a new potential to decrease cholesterol in patients with severe hypercholesterolemia and in particular in homozygote familial hypercholesterolemia. Last, cholesteryl ester transfer protein inhibitors have shown powerful effects on c-HDL and c-LDL, although their efficacy in cardiovascular prevention and safety has not been demonstrated yet. We provide in this article an overview of the main characteristics of therapeutic agents for hypercholesterolemia, which have been recently approved or in an advanced research stage.

  17. Advances in antithrombotic agents.

    PubMed

    Chakrabarti, Ranjan; Das, Saibal Kumar

    2007-07-01

    Thrombosis is the condition where an imbalance in the homeostatic mechanism results in unwanted intravascular thrombus formation. Imbalances in this highly regulated process of coagulation and anticoagulation can lead to a variety of pathophysiological conditions leading to stroke, pulmonary heart attack and other serious conditions. In the western world, thromboembolic diseases are the leading cause of morbidity and mortality. Remarkable progress has occurred over the last decade in the development of antithrombotic drugs, which can be classified into 3 major categories - Anticoagulants, Antiplatelets and thrombolytics. Increased understanding of the pathobiology of thrombotic and vascular disorders has helped researchers to target novel pathways involving the coagulation, thrombolytic, fibrinolytic and integrin systems. Traditionally aspirin and unfractionated heparin was used for myocardial infarction. Newer antiplatelet agents such as, clopidogrel, GP IIb/IIIa inhibitors, low molecular weight heparin, direct thrombin inhibitors and several improved thrombolytic agents have been introduced for clinical use. This review will discuss different important drugs, which have been launched in recent years and also some new targets pursued by different companies. PMID:17630943

  18. Embodied artificial agents for understanding human social cognition

    PubMed Central

    Wykowska, Agnieszka; Chaminade, Thierry; Cheng, Gordon

    2016-01-01

    In this paper, we propose that experimental protocols involving artificial agents, in particular the embodied humanoid robots, provide insightful information regarding social cognitive mechanisms in the human brain. Using artificial agents allows for manipulation and control of various parameters of behaviour, appearance and expressiveness in one of the interaction partners (the artificial agent), and for examining effect of these parameters on the other interaction partner (the human). At the same time, using artificial agents means introducing the presence of artificial, yet human-like, systems into the human social sphere. This allows for testing in a controlled, but ecologically valid, manner human fundamental mechanisms of social cognition both at the behavioural and at the neural level. This paper will review existing literature that reports studies in which artificial embodied agents have been used to study social cognition and will address the question of whether various mechanisms of social cognition (ranging from lower- to higher-order cognitive processes) are evoked by artificial agents to the same extent as by natural agents, humans in particular. Increasing the understanding of how behavioural and neural mechanisms of social cognition respond to artificial anthropomorphic agents provides empirical answers to the conundrum ‘What is a social agent?’ PMID:27069052

  19. Embodied artificial agents for understanding human social cognition.

    PubMed

    Wykowska, Agnieszka; Chaminade, Thierry; Cheng, Gordon

    2016-05-01

    In this paper, we propose that experimental protocols involving artificial agents, in particular the embodied humanoid robots, provide insightful information regarding social cognitive mechanisms in the human brain. Using artificial agents allows for manipulation and control of various parameters of behaviour, appearance and expressiveness in one of the interaction partners (the artificial agent), and for examining effect of these parameters on the other interaction partner (the human). At the same time, using artificial agents means introducing the presence of artificial, yet human-like, systems into the human social sphere. This allows for testing in a controlled, but ecologically valid, manner human fundamental mechanisms of social cognition both at the behavioural and at the neural level. This paper will review existing literature that reports studies in which artificial embodied agents have been used to study social cognition and will address the question of whether various mechanisms of social cognition (ranging from lower- to higher-order cognitive processes) are evoked by artificial agents to the same extent as by natural agents, humans in particular. Increasing the understanding of how behavioural and neural mechanisms of social cognition respond to artificial anthropomorphic agents provides empirical answers to the conundrum 'What is a social agent?'

  20. Embodied artificial agents for understanding human social cognition.

    PubMed

    Wykowska, Agnieszka; Chaminade, Thierry; Cheng, Gordon

    2016-05-01

    In this paper, we propose that experimental protocols involving artificial agents, in particular the embodied humanoid robots, provide insightful information regarding social cognitive mechanisms in the human brain. Using artificial agents allows for manipulation and control of various parameters of behaviour, appearance and expressiveness in one of the interaction partners (the artificial agent), and for examining effect of these parameters on the other interaction partner (the human). At the same time, using artificial agents means introducing the presence of artificial, yet human-like, systems into the human social sphere. This allows for testing in a controlled, but ecologically valid, manner human fundamental mechanisms of social cognition both at the behavioural and at the neural level. This paper will review existing literature that reports studies in which artificial embodied agents have been used to study social cognition and will address the question of whether various mechanisms of social cognition (ranging from lower- to higher-order cognitive processes) are evoked by artificial agents to the same extent as by natural agents, humans in particular. Increasing the understanding of how behavioural and neural mechanisms of social cognition respond to artificial anthropomorphic agents provides empirical answers to the conundrum 'What is a social agent?' PMID:27069052

  1. Time-Extended Payoffs for Collectives of Autonomous Agents

    NASA Technical Reports Server (NTRS)

    Tumer, Kagan; Agogino, Adrian K.

    2002-01-01

    A collective is a set of self-interested agents which try to maximize their own utilities, along with a a well-defined, time-extended world utility function which rates the performance of the entire system. In this paper, we use theory of collectives to design time-extended payoff utilities for agents that are both aligned with the world utility, and are "learnable", i.e., the agents can readily see how their behavior affects their utility. We show that in systems where each agent aims to optimize such payoff functions, coordination arises as a byproduct of the agents selfishly pursuing their own goals. A game theoretic analysis shows that such payoff functions have the net effect of aligning the Nash equilibrium, Pareto optimal solution and world utility optimum, thus eliminating undesirable behavior such as agents working at cross-purposes. We then apply collective-based payoff functions to the token collection in a gridworld problem where agents need to optimize the aggregate value of tokens collected across an episode of finite duration (i.e., an abstracted version of rovers on Mars collecting scientifically interesting rock samples, subject to power limitations). We show that, regardless of the initial token distribution, reinforcement learning agents using collective-based payoff functions significantly outperform both natural extensions of single agent algorithms and global reinforcement learning solutions based on "team games".

  2. Flexible, secure agent development framework

    DOEpatents

    Goldsmith; Steven Y.

    2009-04-07

    While an agent generator is generating an intelligent agent, it can also evaluate the data processing platform on which it is executing, in order to assess a risk factor associated with operation of the agent generator on the data processing platform. The agent generator can retrieve from a location external to the data processing platform an open site that is configurable by the user, and load the open site into an agent substrate, thereby creating a development agent with code development capabilities. While an intelligent agent is executing a functional program on a data processing platform, it can also evaluate the data processing platform to assess a risk factor associated with performing the data processing function on the data processing platform.

  3. Chemical Warfare Agent Degradation and Decontamination

    SciTech Connect

    Talmage, Sylvia Smith; Watson, Annetta Paule; Hauschild, Veronique; Munro, Nancy B; King, J.

    2007-02-01

    The decontamination of chemical warfare agents (CWA) from structures, environmental media, and even personnel has become an area of particular interest in recent years due to increased homeland security concerns. In addition to terrorist attacks, scenarios such as accidental releases of CWA from U.S. stockpile sites or from historic, buried munitions are also subjects for response planning. To facilitate rapid identification of practical and effective decontamination approaches, this paper reviews pathways of CWA degradation by natural means as well as those resulting from deliberately applied solutions and technologies; these pathways and technologies are compared and contrasted. We then review various technologies, both traditional and recent, with some emphasis on decontamination materials used for surfaces that are difficult to clean. Discussion is limited to the major threat CWA, namely sulfur mustard (HD, bis(2-chloroethyl)sulfide), VX (O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothioate), and the G-series nerve agents. The principal G-agents are GA (tabun, ethyl N,N-dimethylphosphoramidocyanidate), GB (sarin, isopropyl methylphosphonofluoridate), and GD (soman, pinacolyl methylphosphonofluoridate). The chemical decontamination pathways of each agent are outlined, with some discussion of intermediate and final degradation product toxicity. In all cases, and regardless of the CWA degradation pathway chosen for decontamination, it will be necessary to collect and analyze pertinent environmental samples during the treatment phase to confirm attainment of clearance levels.

  4. Fluoroquinolone antimicrobial agents.

    PubMed Central

    Wolfson, J S; Hooper, D C

    1989-01-01

    The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial target is the enzyme deoxyribonucleic acid gyrase. Bacterial resistance occurs by chromosomal mutations altering deoxyribonucleic acid gyrase and decreasing drug permeation. The drugs are bactericidal and potent in vitro against members of the family Enterobacteriaceae, Haemophilus spp., and Neisseria spp., have good activity against Pseudomonas aeruginosa and staphylococci, and (with several exceptions) are less potent against streptococci and have fair to poor activity against anaerobic species. Potency in vitro decreases in the presence of low pH, magnesium ions, or urine but is little affected by different media, increased inoculum, or serum. The effects of the drugs in combination with a beta-lactam or aminoglycoside are often additive, occasionally synergistic, and rarely antagonistic. The agents are orally absorbed, require at most twice-daily dosing, and achieve high concentrations in urine, feces, and kidney and good concentrations in lung, bone, prostate, and other tissues. The drugs are efficacious in treatment of a variety of bacterial infections, including uncomplicated and complicated urinary tract infections, bacterial gastroenteritis, and gonorrhea, and show promise for therapy of prostatitis, respiratory tract infections, osteomyelitis, and cutaneous infections, particularly when caused by aerobic gram-negative bacilli. Fluoroquinolones have also proved to be efficacious for prophylaxis against travelers' diarrhea and infection with gram-negative bacilli in neutropenic patients. The drugs are effective in eliminating carriage of Neisseria meningitidis. Patient tolerability appears acceptable, with gastrointestinal or central nervous

  5. Health protection: Toxic agent and radiation control.

    PubMed

    1983-01-01

    It is estimated that of the four million chemical compounds which have been synthesized or isolated from natural materials, more than 55,000 are produced commercially. Approximately 1,000 new compounds are introduced annually; pesticide formulations alone contain about 1,500 active chemical ingredients. Diagnostic x-rays are used extensively in medicine and dentistry. Over 2,000 chemicals are suspected carcinogens in laboratory animals--epidemiologic evidence suggests that 26 of these chemicals and/or industrial processes are carcinogenic in humans. More than 20 agents are known to be associated with birth defects in humans; 47 atmospheric contaminants have been identified in animal studies as recognized carcinogens and 128 as mutagens; and, of the 765 contaminants identified in drinking water, 12 were recognized carcinogens, 31 suspected carcinogens, and 59 mutagens. Radiation has known carcinogenic and genetic effects at significant levels of exposure. Problems with toxic agents and radiation sources occur not only in industry, but also in medical and dental care (x-rays and drugs), agriculture (pesticides and herbicides), Government activities (biological and chemical agents), consumer products (incorrect use of consumer products which contain toxic substances), and natural sources (fungal products).

  6. A simulation-based tutor that reasons about multiple agents

    SciTech Connect

    Rhodes Eliot, C. III; Park Woolf, B.

    1996-12-31

    This paper examines the problem of modeling multiple agents within an intelligent simulation-based tutor. Multiple agent and planning technology were used to enable the system to critique a human agent`s reasoning about multiple agents. This perspective arises naturally whenever a student must learn to lead and coordinate a team of people. The system dynamically selected teaching goals, instantiated plans and modeled the student and the domain as it monitored the student`s progress. The tutor provides one of the first complete integrations of a real-time simulation with knowledge-based reasoning. Other novel techniques of the system are reported, such as common-sense reasoning about plans, reasoning about protocol mechanisms, and using a real-time simulation for training.

  7. Arylthiosemicarbazones as antileishmanial agents.

    PubMed

    Manzano, José Ignacio; Cochet, Florent; Boucherle, Benjamin; Gómez-Pérez, Verónica; Boumendjel, Ahcène; Gamarro, Francisco; Peuchmaur, Marine

    2016-11-10

    Based on a screening process, we targeted substituted thiosemicarbazone as potential antileishmanial agents. Our objective was to identify the key structural elements contributing to the anti-parasite activity that might be used for development of effective drugs. A series of 32 compounds was synthesized and their efficacy was evaluated against the clinically relevant intracellular amastigotes of Leishmania donovani. From these, 22 compounds showed EC50 values below 10 μM with the most active derivative (compound 14) showing an EC50 of 0.8 μM with very low toxicity on two different mammalian cell lines. The most relevant structural elements required for higher activity indicate that the presence of a fused bicyclic aromatic ring such as a naphthalene bearing an alkyl or an alkoxy group substituent are prerequisites. Owing to the easy synthesis, high activity and low toxicity, the most active compounds could be considered as a lead for further development.

  8. Itch Management: Topical Agents.

    PubMed

    Metz, Martin; Staubach, Petra

    2016-01-01

    Chronic pruritus is a common problem in patients with inflammatory skin diseases as well as in subjects with dry or sensitive skin. Regardless of the underlying cause of the pruritus, a topical therapy is not only useful but most often necessary to achieve symptom control. A good topical therapy should fulfill different functions. An optimal basic therapy based on the condition of the skin is important to repair epithelial barrier defects and to rehydrate the skin. An adequate disease-specific topical therapy is crucial for inflamed skin, e.g. anti-inflammatory topical therapy is an important part in the treatment of atopic dermatitis. Finally, the use of specific antipruritic substances can help to improve pruritus in patients irrespective of the underlying disease. Here, we summarize topical agents used in the treatment of chronic pruritus. PMID:27578070

  9. [Ribonucleases as antiviral agents].

    PubMed

    Il'inskaia, O N; Shakh Makhmud, R

    2014-01-01

    Many ribonucleases (RNases) are able to inhibit the reproduction of viruses in infected cell cultures and laboratory animals, but molecular mechanisms of their antiviral activity remain unclear. The review observes the most known RNases which possess established antiviral effects, actually intracellular RNases (RNase L, MCPIPI protein, eosinophylic RNases) as well as exogenously applied ones (RNase A, BS-RNase, onconase, binase, synthetic RNases). Attention is given on two important but not always obligatory aspects in molecule of RNases, which have antiviral properties: catalytic activity and ability to the dimerization. The hypothetic scheme of virus elimination by exogenous RNases, that reflects possible types of interaction of viruses and RNases with a cell, is proposed. The evidence for RNases as classical components of immune defense which are perspective agents for development of new antiviral therapeutics is produced.

  10. Evolution of cooperation among mobile agents with heterogenous view radii

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Wang, Wei-Ye; Du, Wen-Bo; Cao, Xian-Bin

    2011-06-01

    In this paper, we study cooperative behavior among mobile agents; the agents have heterogenous view radii and they play the prisoner’s dilemma game with those being within their vision fields. It is found that the cooperation level is remarkably promoted when the heterogeneity of view radii is considered, and the degree distribution of the system is investigated to explain this interesting phenomenon. Moreover, we report that the cooperative behavior is best favored by low density, moderate view radius, and small moving speed. Our findings may be helpful in understanding cooperative behavior in natural and social systems consisting of mobile agents.

  11. The Development of Sugar-Based Anti-Melanogenic Agents

    PubMed Central

    Bin, Bum-Ho; Kim, Sung Tae; Bhin, Jinhyuk; Lee, Tae Ryong; Cho, Eun-Gyung

    2016-01-01

    The regulation of melanin production is important for managing skin darkness and hyperpigmentary disorders. Numerous anti-melanogenic agents that target tyrosinase activity/stability, melanosome maturation/transfer, or melanogenesis-related signaling pathways have been developed. As a rate-limiting enzyme in melanogenesis, tyrosinase has been the most attractive target, but tyrosinase-targeted treatments still pose serious potential risks, indicating the necessity of developing lower-risk anti-melanogenic agents. Sugars are ubiquitous natural compounds found in humans and other organisms. Here, we review the recent advances in research on the roles of sugars and sugar-related agents in melanogenesis and in the development of sugar-based anti-melanogenic agents. The proposed mechanisms of action of these agents include: (a) (natural sugars) disturbing proper melanosome maturation by inducing osmotic stress and inhibiting the PI3 kinase pathway and (b) (sugar derivatives) inhibiting tyrosinase maturation by blocking N-glycosylation. Finally, we propose an alternative strategy for developing anti-melanogenic sugars that theoretically reduce melanosomal pH by inhibiting a sucrose transporter and reduce tyrosinase activity by inhibiting copper incorporation into an active site. These studies provide evidence of the utility of sugar-based anti-melanogenic agents in managing skin darkness and curing pigmentary disorders and suggest a future direction for the development of physiologically favorable anti-melanogenic agents. PMID:27092497

  12. Naturally Inspired Molecules as Multifunctional Agents for Alzheimer's Disease Treatment.

    PubMed

    Rampa, Angela; Tarozzi, Andrea; Mancini, Francesca; Pruccoli, Letizia; Di Martino, Rita Maria Concetta; Gobbi, Silvia; Bisi, Alessandra; De Simone, Angela; Palomba, Francesco; Zaccheroni, Nelsi; Belluti, Federica

    2016-05-16

    Alzheimer's disease (AD) has been defined as a multi-factorial disorder resulting from a complex array of networked cellular and molecular mechanisms. In particular, elevated levels of Aβ protein and its aggregation products in the presence of metal ions proved to be highly neurotoxic and therapeutic strategies aimed at preventing Aβ generation and oxidative stress may represent an effective approach for AD treatment. A recent paradigm for the treatment of complex diseases such as AD suggests the employment of multifunctional compounds, single chemical entities capable of simultaneously modulating different targets involved in the pathology. In this paper, the "pharmacophores combination" strategy was applied, connecting the main scaffold of the BACE-1 ligand 1 to that of the chalcone 2, as metal chelating pharmacophore, to obtain a small library of compounds. Conjugate 5 emerged as the most interesting derivative, proving to inhibit BACE-1 with low-micromolar potency, and showing neuroprotective effects. In particular, 5 proved to be able to protect from metal-associated oxidative stress by hampering intracellular Cu(2+)-induced ROS formation without any direct neurotoxic effect.

  13. A natural anticancer agent thaspine targets human topoisomerase IB.

    PubMed

    Castelli, Silvia; Katkar, Prafulla; Vassallo, Oscar; Falconi, Mattia; Linder, Stig; Desideri, Alessandro

    2013-02-01

    The different steps of the topoisomerase I catalytic cycle have been analyzed in the presence of the plant alkaloid thaspine (1- (2-(Dimethylamino)ethyl)-3,8-dimethoxychromeno[5,4,3-cde]chromene-5,10-dione), known to induce apoptosis in colon carcinoma cells. The experiments indicate that thaspine inhibits both the cleavage and the religation steps of the enzyme reaction. The inhibition is reversible and the effect is enhanced upon pre-incubation. Molecular docking simulations of thaspine over topoisomerase I, in the presence or absence of the DNA substrate, show that thaspine, when interacting with the enzyme alone in the closed or in the open state, can bind in proximity of the active residues preventing the cleavage reaction, whilst when docked with the enzyme-DNA cleavable complex intercalates between the DNA bases in a way similar to that found for camptothecin, explaining its religation inhibition. These results unequivocally demonstrate that thaspine targets human topoisomerase I .

  14. A review on promising natural agents effective on hyperlipidemia.

    PubMed

    Bahmani, Mahmoud; Mirhoseini, Mahmoud; Shirzad, Hedayatollah; Sedighi, Mehrnoosh; Shahinfard, Nejmeh; Rafieian-Kopaei, Mahmoud

    2015-07-01

    Hyperlipidemia is a prevalent disease and a major component of the metabolic syndrome resulting from various factors. This disease increases morbidity and mortality when combined with other prevalent diseases such as diabetes mellitus, hypertension, and cardiovascular diseases. The side effects of the current lipid-lowering drugs have increased the tendency to move toward traditional and alternative treatments. Epidemiological observations indicate that using alternative treatments, consumption of medicinal plants, diet, and consumption of fruits have had satisfactory results on the effects of hyperlipidemia in many societies. It should be noted that in majority of societies, even developed countries, the tendency toward eating lipid-lowering medicinal plants has increased extensively. Using these plants especially when common remedies cannot control the disease is significant. Although consumption of medicinal plants by hyperlipidemic patients may show improvement in disease state, drug interaction and side effects may cause complications in disease control. Therefore, in this review, apart from introducing some of the reliable plants effective in inhibition and decrease of hyperlipidemia, the possibility of their intoxication and drug interaction is also presented. PMID:25633423

  15. Naturally Inspired Molecules as Multifunctional Agents for Alzheimer's Disease Treatment.

    PubMed

    Rampa, Angela; Tarozzi, Andrea; Mancini, Francesca; Pruccoli, Letizia; Di Martino, Rita Maria Concetta; Gobbi, Silvia; Bisi, Alessandra; De Simone, Angela; Palomba, Francesco; Zaccheroni, Nelsi; Belluti, Federica

    2016-01-01

    Alzheimer's disease (AD) has been defined as a multi-factorial disorder resulting from a complex array of networked cellular and molecular mechanisms. In particular, elevated levels of Aβ protein and its aggregation products in the presence of metal ions proved to be highly neurotoxic and therapeutic strategies aimed at preventing Aβ generation and oxidative stress may represent an effective approach for AD treatment. A recent paradigm for the treatment of complex diseases such as AD suggests the employment of multifunctional compounds, single chemical entities capable of simultaneously modulating different targets involved in the pathology. In this paper, the "pharmacophores combination" strategy was applied, connecting the main scaffold of the BACE-1 ligand 1 to that of the chalcone 2, as metal chelating pharmacophore, to obtain a small library of compounds. Conjugate 5 emerged as the most interesting derivative, proving to inhibit BACE-1 with low-micromolar potency, and showing neuroprotective effects. In particular, 5 proved to be able to protect from metal-associated oxidative stress by hampering intracellular Cu(2+)-induced ROS formation without any direct neurotoxic effect. PMID:27196880

  16. Relaxin as a natural agent for vascular health

    PubMed Central

    Bani, Daniele

    2008-01-01

    Hypertension, atherothrombosis, myocardial infarction, stroke, peripheral vascular disease, and renal failure are the main manifestations of cardiovascular disease (CVD), the leading cause of death and disability in developed countries. Continuing insight into the pathophysiology of CVD can allow identification of effective therapeutic strategies to reduce the occurrence of death and/or severe disabilities. In this context, a healthy endothelium is deemed crucial to proper functioning and maintenance of anatomical integrity of the vascular system in many organs. Of note, epidemiologic studies indicate that the incidence of CVD in women is very low until menopause and increases sharply thereafter. The loss of protection against CVD in post-menopausal women has been chiefly attributed to ovarian steroid deficiency. However, besides steroids, the ovary also produces the peptide hormone relaxin (RLX), which provides potent vasoactive effects which render it the most likely candidate as the elusive physiological shield against CVD in fertile women. In particular, RLX has a specific relaxant effect on peripheral and coronary vasculature, exerted by the stimulation of endogenous nitric oxide (NO) generation by cells of the vascular wall, and can induce angiogenesis. Moreover, RLX inhibits the activation of inflammatory leukocytes and platelets, which play a key role in CVD. Experimental studies performed in vascular and blood cell in vitro and in animal models of vascular dysfunction, as well as pioneer clinical observations, have provided evidence that RLX can prevent and/or improve CVD, thus offering background to clinical trials aimed at exploring the broad therapeutic potential of human recombinant RLX as a new cardiovascular drug. PMID:18827902

  17. A review on promising natural agents effective on hyperlipidemia.

    PubMed

    Bahmani, Mahmoud; Mirhoseini, Mahmoud; Shirzad, Hedayatollah; Sedighi, Mehrnoosh; Shahinfard, Nejmeh; Rafieian-Kopaei, Mahmoud

    2015-07-01

    Hyperlipidemia is a prevalent disease and a major component of the metabolic syndrome resulting from various factors. This disease increases morbidity and mortality when combined with other prevalent diseases such as diabetes mellitus, hypertension, and cardiovascular diseases. The side effects of the current lipid-lowering drugs have increased the tendency to move toward traditional and alternative treatments. Epidemiological observations indicate that using alternative treatments, consumption of medicinal plants, diet, and consumption of fruits have had satisfactory results on the effects of hyperlipidemia in many societies. It should be noted that in majority of societies, even developed countries, the tendency toward eating lipid-lowering medicinal plants has increased extensively. Using these plants especially when common remedies cannot control the disease is significant. Although consumption of medicinal plants by hyperlipidemic patients may show improvement in disease state, drug interaction and side effects may cause complications in disease control. Therefore, in this review, apart from introducing some of the reliable plants effective in inhibition and decrease of hyperlipidemia, the possibility of their intoxication and drug interaction is also presented.

  18. The pandemonium system of reflective agents.

    PubMed

    Smieja, F

    1996-01-01

    The Pandemonium system of reflective MINOS agents solves problems by automatic dynamic modularization of the input space. The agents contain feedforward neural networks which adapt using the backpropagation algorithm. We demonstrate the performance of Pandemonium on various categories of problems. These include learning continuous functions with discontinuities, separating two spirals, learning the parity function, and optical character recognition. It is shown how strongly the advantages gained from using a modularization technique depend on the nature of the problem. The superiority of the Pandemonium method over a single net on the first two test categories is contrasted with its limited advantages for the second two categories. In the first case the system converges quicker with modularization and is seen to lead to simpler solutions. For the second case the problem is not significantly simplified through flat decomposition of the input space, although convergence is still quicker.

  19. Agent-based enterprise integration

    SciTech Connect

    N. M. Berry; C. M. Pancerella

    1998-12-01

    The authors are developing and deploying software agents in an enterprise information architecture such that the agents manage enterprise resources and facilitate user interaction with these resources. The enterprise agents are built on top of a robust software architecture for data exchange and tool integration across heterogeneous hardware and software. The resulting distributed multi-agent system serves as a method of enhancing enterprises in the following ways: providing users with knowledge about enterprise resources and applications; accessing the dynamically changing enterprise; locating enterprise applications and services; and improving search capabilities for applications and data. Furthermore, agents can access non-agents (i.e., databases and tools) through the enterprise framework. The ultimate target of the effort is the user; they are attempting to increase user productivity in the enterprise. This paper describes their design and early implementation and discusses the planned future work.

  20. Collaborating Fuzzy Reinforcement Learning Agents

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid R.

    1997-01-01

    Earlier, we introduced GARIC-Q, a new method for doing incremental Dynamic Programming using a society of intelligent agents which are controlled at the top level by Fuzzy Relearning and at the local level, each agent learns and operates based on ANTARCTIC, a technique for fuzzy reinforcement learning. In this paper, we show that it is possible for these agents to compete in order to affect the selected control policy but at the same time, they can collaborate while investigating the state space. In this model, the evaluator or the critic learns by observing all the agents behaviors but the control policy changes only based on the behavior of the winning agent also known as the super agent.

  1. Radioiodine: the classic theranostic agent.

    PubMed

    Silberstein, Edward B

    2012-05-01

    Radioiodine has the distinction of being the first theranostic agent in our armamentarium. Millennia were required to discover that the agent in orally administered seaweed and its extracts, which had been shown to cure neck swelling due to thyromegaly, was iodine, first demonstrated to be a new element in 1813. Treatment of goiter with iodine began at once, but its prophylactic value to prevent a common form of goiter took another century. After Enrico Fermi produced the first radioiodine, (128)I, in 1934, active experimentation in the United States and France delineated the crucial role of iodine in thyroid metabolism and disease. (130)I and (131)I were first employed to treat thyrotoxicosis by 1941, and thyroid cancer in 1943. After World War II, (131)I became widely available at a reasonable price for diagnostic testing and therapy. The rectilinear scanner of Cassen and Curtis (Science 1949;110:94-95), and a dedicated gamma camera invented by Anger (Nature 1952;170:200-201), finally permitted the diagnostic imaging of thyroid disease, with (131)I again the radioisotope of choice, although there were short-lived attempts to employ (125)I and (132)I for this purpose. (123)I was first produced in 1949 but did not become widely available until about 1982, 10 years after a production technique eliminated high-energy (124)I contamination. I continues to be the radioiodine of choice for the diagnosis of benign thyroid disease, whereas (123)I and (131)I are employed in the staging and detection of functioning thyroid cancer. (124)I, a positron emitter, can produce excellent anatomically correlated images employing positron emission tomography/computed tomography equipment and has the potential to enhance heretofore imperfect dosimetric studies in determining the appropriate administered activity to ablate/treat thyroid cancer. Issues of acceptable measuring error in thyroid cancer dosimetry and the role in (131)I therapy of tumor heterogeneity, tumor hypoxia, and

  2. [Contact sensitization to external agents].

    PubMed

    Erdmann, S M; Merk, H-F

    2003-04-01

    The following review describes contact sensitization to topically applied medications--especially topical dermatological agents--and to external agents in the broadest sense. Particularly skin care products constitute a special source for sensitization due to their widespread use. Especially fragrances and preservatives in cosmetics play an important global role in eliciting contact allergies. Because of the extremely broad spectrum covered by the active and adjuvant ingredients contained in external agents, the following discussion focuses on specific substance groups.

  3. Broad-spectrum antiviral agents

    PubMed Central

    Zhu, Jun-Da; Meng, Wen; Wang, Xiao-Jia; Wang, Hwa-Chain R.

    2015-01-01

    Development of highly effective, broad-spectrum antiviral agents is the major objective shared by the fields of virology and pharmaceutics. Antiviral drug development has focused on targeting viral entry and replication, as well as modulating cellular defense system. High throughput screening of molecules, genetic engineering of peptides, and functional screening of agents have identified promising candidates for development of optimal broad-spectrum antiviral agents to intervene in viral infection and control viral epidemics. This review discusses current knowledge, prospective applications, opportunities, and challenges in the development of broad-spectrum antiviral agents. PMID:26052325

  4. Natural products as photoprotection.

    PubMed

    Saewan, Nisakorn; Jimtaisong, Ampa

    2015-03-01

    The rise in solar ultraviolet radiation on the earth's surface has led to a depletion of stratospheric ozone over recent decades, thus accelerating the need to protect human skin against the harmful effects of UV radiation such as erythema, edema, hyperpigmentation, photoaging, and skin cancer. There are many different ways to protect skin against UV radiation's harmful effects. The most popular way to reduce the amount of UV radiation penetrating the skin is topical application of sunscreen products that contain UV absorbing or reflecting active molecules. Based on their protection mechanism, the active molecules in sunscreens are broadly divided into inorganic and organic agents. Inorganic sunscreens reflect and scatter UV and visible radiation, while organic sunscreens absorb UV radiation and then re-emit energy as heat or light. These synthetic molecules have limited concentration according to regulation concern. Several natural compounds with UV absorption property have been used to substitute for or to reduce the quantity of synthetic sunscreen agents. In addition to UV absorption property, most natural compounds were found to act as antioxidants, anti-inflammatory, and immunomodulatory agents, which provide further protection against the damaging effects of UV radiation exposure. Compounds derived from natural sources have gained considerable attention for use in sunscreen products and have bolstered the market trend toward natural cosmetics. This adds to the importance of there being a wide selection of active molecules in sunscreen formulations. This paper summarizes a number of natural products derived from propolis, plants, algae, and lichens that have shown potential photoprotection properties against UV radiation exposure-induced skin damage. PMID:25582033

  5. Natural products as photoprotection.

    PubMed

    Saewan, Nisakorn; Jimtaisong, Ampa

    2015-03-01

    The rise in solar ultraviolet radiation on the earth's surface has led to a depletion of stratospheric ozone over recent decades, thus accelerating the need to protect human skin against the harmful effects of UV radiation such as erythema, edema, hyperpigmentation, photoaging, and skin cancer. There are many different ways to protect skin against UV radiation's harmful effects. The most popular way to reduce the amount of UV radiation penetrating the skin is topical application of sunscreen products that contain UV absorbing or reflecting active molecules. Based on their protection mechanism, the active molecules in sunscreens are broadly divided into inorganic and organic agents. Inorganic sunscreens reflect and scatter UV and visible radiation, while organic sunscreens absorb UV radiation and then re-emit energy as heat or light. These synthetic molecules have limited concentration according to regulation concern. Several natural compounds with UV absorption property have been used to substitute for or to reduce the quantity of synthetic sunscreen agents. In addition to UV absorption property, most natural compounds were found to act as antioxidants, anti-inflammatory, and immunomodulatory agents, which provide further protection against the damaging effects of UV radiation exposure. Compounds derived from natural sources have gained considerable attention for use in sunscreen products and have bolstered the market trend toward natural cosmetics. This adds to the importance of there being a wide selection of active molecules in sunscreen formulations. This paper summarizes a number of natural products derived from propolis, plants, algae, and lichens that have shown potential photoprotection properties against UV radiation exposure-induced skin damage.

  6. Norms, Action and Agency in Multi-agent Systems

    NASA Astrophysics Data System (ADS)

    Sergot, Marek

    This presentation has two parts. The technical part concerns the logic of expressions of the form 'agent x brings it about that A', or 'agent x is responsible for its being the case that A', or more generally, 'the group of agents G collectively, though perhaps inadvertently, bring it about that A'. I will present an account that combines this agency view of action with the transition based conceptions more usually encountered in computer science and temporal logic. A two-sorted (modal) language is defined for talking about properties of states and transitions in a transition system, and about the actions of individual agents or groups of agents, including two modalities of the 'brings it about' kind. Since no assumptions at all are made about the reasoning or perceptual capabilities of the agents - they can be human, or computer agents, or simple reactive devices - I refer to this form of agency as 'unwitting'; unwitting can mean both inadvertent and unaware. The resulting logic bears a resemblance to Ingmar Pörn's (1977) logic of 'brings it about' though there are differences, The account generalises naturally to talking about the collective actions of groups of agents: several different forms of (unwitting) collective agency can be identified.

  7. Incorporating BDI Agents into Human-Agent Decision Making Research

    NASA Astrophysics Data System (ADS)

    Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia

    Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.

  8. Plasmids encoding therapeutic agents

    DOEpatents

    Keener, William K.

    2007-08-07

    Plasmids encoding anti-HIV and anti-anthrax therapeutic agents are disclosed. Plasmid pWKK-500 encodes a fusion protein containing DP178 as a targeting moiety, the ricin A chain, an HIV protease cleavable linker, and a truncated ricin B chain. N-terminal extensions of the fusion protein include the maltose binding protein and a Factor Xa protease site. C-terminal extensions include a hydrophobic linker, an L domain motif peptide, a KDEL ER retention signal, another Factor Xa protease site, an out-of-frame buforin II coding sequence, the lacZ.alpha. peptide, and a polyhistidine tag. More than twenty derivatives of plasmid pWKK-500 are described. Plasmids pWKK-700 and pWKK-800 are similar to pWKK-500 wherein the DP178-encoding sequence is substituted by RANTES- and SDF-1-encoding sequences, respectively. Plasmid pWKK-900 is similar to pWKK-500 wherein the HIV protease cleavable linker is substituted by a lethal factor (LF) peptide-cleavable linker.

  9. Guanidinoacetic acid as a performance-enhancing agent.

    PubMed

    Ostojic, Sergej M

    2016-08-01

    Guanidinoacetic acid (GAA; also known as glycocyamine or guanidinoacetate) is the natural precursor of creatine, and under investigation as a novel dietary agent. It was first identified as a natural compound in humans ~80 years ago. In the 1950s, GAA's use as a therapeutic agent was explored, showing that supplemental GAA improved patient-reported outcomes and work capacity in clinical populations. Recently, a few studies have examined the safety and efficacy of GAA and suggest potential ergogenic benefits for physically active men and women. The purpose of this review is to examine possible applications of GAA supplementation for exercise performance enhancement, safety, and legislation issues. PMID:26445773

  10. Instructable autonomous agents. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Huffman, Scott Bradley

    1994-01-01

    In contrast to current intelligent systems, which must be laboriously programmed for each task they are meant to perform, instructable agents can be taught new tasks and associated knowledge. This thesis presents a general theory of learning from tutorial instruction and its use to produce an instructable agent. Tutorial instruction is a particularly powerful form of instruction, because it allows the instructor to communicate whatever kind of knowledge a student needs at whatever point it is needed. To exploit this broad flexibility, however, a tutorable agent must support a full range of interaction with its instructor to learn a full range of knowledge. Thus, unlike most machine learning tasks, which target deep learning of a single kind of knowledge from a single kind of input, tutorability requires a breadth of learning from a broad range of instructional interactions. The theory of learning from tutorial instruction presented here has two parts. First, a computational model of an intelligent agent, the problem space computational model, indicates the types of knowledge that determine an agent's performance, and thus, that should be acquirable via instruction. Second, a learning technique, called situated explanation specifies how the agent learns general knowledge from instruction. The theory is embodied by an implemented agent, Instructo-Soar, built within the Soar architecture. Instructo-Soar is able to learn hierarchies of completely new tasks, to extend task knowledge to apply in new situations, and in fact to acquire every type of knowledge it uses during task performance - control knowledge, knowledge of operators' effects, state inferences, etc. - from interactive natural language instructions. This variety of learning occurs by applying the situated explanation technique to a variety of instructional interactions involving a variety of types of instructions (commands, statements, conditionals, etc.). By taking seriously the requirements of flexible

  11. TACtic- A Multi Behavioral Agent for Trading Agent Competition

    NASA Astrophysics Data System (ADS)

    Khosravi, Hassan; Shiri, Mohammad E.; Khosravi, Hamid; Iranmanesh, Ehsan; Davoodi, Alireza

    Software agents are increasingly being used to represent humans in online auctions. Such agents have the advantages of being able to systematically monitor a wide variety of auctions and then make rapid decisions about what bids to place in what auctions. They can do this continuously and repetitively without losing concentration. To provide a means of evaluating and comparing (benchmarking) research methods in this area the trading agent competition (TAC) was established. This paper describes the design, of TACtic. Our agent uses multi behavioral techniques at the heart of its decision making to make bidding decisions in the face of uncertainty, to make predictions about the likely outcomes of auctions, and to alter the agent's bidding strategy in response to the prevailing market conditions.

  12. Departments as Agents of Change

    NASA Astrophysics Data System (ADS)

    Lagowski, J. J.

    1996-07-01

    Higher education is changing because it has no choice. And, for the most part, outside influences are dictating the processes of change. The more fortunate institutions have had a flat budget during this period, but most have been forced to deal with a declining revenue stream as well. Legislators seem bent on micromanaging state-supported institutions, even as they cut their support. Regulators demand greater institutional accountability. Students and their parents expect more service at lower prices and increased flexibility. Technological advances have dramatically affected the availability and accessibility of extant knowledge. It is no longer a question of whether institutions will change, but rather, who will control the change. Most institutions possess long-standing academic traditions, but these are placed at risk in an increasingly competitive market that holds little sympathy for such traditions and may even see them as obstacles or barriers. As a result, the change agents will undoubtedly have a profound effect on the very nature of academic institutions. From the academic point of view, it would seem prudent to attempt to manage the changes that will inevitably occur. A number of concerned observers, notably the Pew Higher Education Roundtable and the American Association for Higher Education, argue persuasively that the academic department is the logical focus for responding to the current winds of change. Using a marketing metaphor, the academic department has been likened to a "producers' cooperative" of services that consumers seek. Thus, the department should be held accountable for the quality of teaching delivered by its members, for the coherence of its major, for its contributions to the general education curriculum, and for supervising and rewarding its individual faculty members. If departments are to be held accountable, it is surely in their best interest to act in such a way that they are accountable. Expecting academic departments to be

  13. Search for antisickling agents from plants

    PubMed Central

    Dash, Bisnu Prasad; Archana, Y.; Satapathy, Nibarana; Naik, Soumendra Kumar

    2013-01-01

    The sickle cell disease is fatal in nature. Thousands of children are dying off due to this health problem throughout the globe. Due to the rapid development of diagnosis and clinical managements such patients are living up to a respectable age. But as there is no permanent cure the patients are suffering from bone and joint pain, jaundice, hepato-splenomegaly, chronic infections etc. The main physiological complicacy is due to the polymerization of sickle hemoglobin (HbS), (sickling process) inside the red blood cell (RBC) of these patients during deoxygenating state. The change of RBC from spherical to sickle shape is due to the polymerization of mutant hemoglobin (HbS) inside the RBC and membrane distortion during anoxic condition. The mechanism and the process of sickling are very complex and multifactor in nature. To get rid from such complicacies it is necessary to suitably and accurately stop the sickling of RBC of the patients. The potential anti-sickling agents either from natural sources and/or synthetic molecules may be helpful for reducing the clinical morbidity of the patients. A lot of natural compounds from plant extracts have been tried by several workers in recent past. Most of the studies are based on in vitro red cell sickling studies and their mode of action has not been properly understood. Although, few studies have been in vivo in nature pertaining to transgenic sickle animal model, there is paucity of data on the human studies. The result of such studies although has shown some degree of success, a promising anti-sickling agent is yet to be established. PMID:23922457

  14. Novel approaches to discovery of antibacterial agents.

    PubMed

    Taylor, Patricia L; Wright, Gerard D

    2008-12-01

    Antimicrobial resistance is a rapidly increasing problem impacting the successful treatment of bacterial infectious disease. To combat resistance, the development of new treatment options is required. Recent advances in technology have aided in the discovery of novel antibacterial agents, specifically through genome mining for novel natural product biosynthetic gene clusters and improved small molecule high-throughput screening methods. Novel targets such as lipopolysaccharide and fatty acid biosyntheses have been identified by essential gene studies, representing a shift from traditional antibiotic targets. Finally, inhibiting non-essential genes with small molecules is being explored as a method for rescuing the activity of 'old' antibiotics, providing a novel synergistic approach to antimicrobial discovery.

  15. Natural Products as Molecular Messengers*

    PubMed Central

    Meinwald, Jerrold

    2011-01-01

    The chemistry of naturally-occurring compounds has long been pursued in the search for medicines, dyes, pesticides, flavors, and fragrances. In addition, the deeper aim of understanding life itself as a chemical phenomenon has motivated generations of scientists. One consequence of such studies has been the realization that natural products often serve central roles as biological signaling agents. We consider natural products from the viewpoint of the organisms that produce and/or respond to them, and suggest how a naturally-occurring compound may acquire its role in chemical communication. PMID:21190370

  16. Hypersensitivity to antineoplastic agents.

    PubMed

    Castells, M C

    2008-01-01

    The need to offer first line therapy for primary and recurrent cancers has spurred the clinical development of rapid desensitizations for chemotherapy and monoclonal antibodies. Rapid desensitizations allow patients to be treated with medications to which they have presented with hypersensitivity reactions (HSRs), including anaphylaxis. Rapid desensitization achieves temporary tolerization to full therapeutic doses by slow administration of incremental doses of the drug inducing the HSR. Protocols are available for most chemotherapy agents, including taxanes, platins, doxorubicin, monoclonal antibodies, and others. Candidate patients include those who present with type I HSRs, mast cell/IgE dependent, including anaphylaxis, and non-IgE mediated HSRs, during the chemotherapy infusion or shortly after. Idiosyncratic reactions, erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis are not amenable to rapid desensitization. The recommendation for rapid desensitization can only be made by allergy and immunology specialists and can only be performed in settings with one-to-one nurse-patient care and where resuscitation personnel and resources are readily available. Repeated desensitizations can be safely performed in outpatient settings with similar conditions, which allow cancer patients to remain in clinical studies. We have generated a universal 12-step protocol that was applied to 413 cases of intravenous and intraperitoneal rapid desensitizations using taxanes, platins, liposomal doxorubicin, doxorubicin, rituximab, and other chemotherapy drugs. Under this protocol all patients were able to complete their target dose, and 94% of the patients had limited or no reactions. No deaths or codes were reported, indicating that the procedure was safe and effective in delivering first line chemotherapy drugs. PMID:18991707

  17. Agent-Based Literacy Theory

    ERIC Educational Resources Information Center

    McEneaney, John E.

    2006-01-01

    The purpose of this theoretical essay is to explore the limits of traditional conceptualizations of reader and text and to propose a more general theory based on the concept of a literacy agent. The proposed theoretical perspective subsumes concepts from traditional theory and aims to account for literacy online. The agent-based literacy theory…

  18. Gelled Anti-icing Agents

    NASA Technical Reports Server (NTRS)

    Markles, O. F.; Sperber, H. H.

    1983-01-01

    Pectin added to antifreeze/water mixture. Formulations include water with dimethyl sulfoxide (DMSO) as deicer and pectin as gel former. Without gelling agent, deicer runs off vertical surfaces. Without pectin solution will completely evaporate in far less time. Agents developed have wide potential for ice prevention on runways, highways, bridges and sidewalks.

  19. Dialogue Games for Agent Argumentation

    NASA Astrophysics Data System (ADS)

    McBurney, Peter; Parsons, Simon

    The rise of the Internet and the growth of distributed computing have led to a major paradigm shift in software engineering and computer science. Until recently, the notion of computation has been variously construed as numerical calculation, as information processing, or as intelligent symbol analysis, but increasingly, it is now viewed as distributed cognition and interaction between intelligent entities [60]. This new view has major implications for the conceptualization, design, engineering and control of software systems, most profoundly expressed in the concept of systems of intelligent software agents, or multi-agent systems [99]. Agents are software entities with control over their own execution; the design of such agents, and of multi-agent systems of them, presents major research and software engineering challenges to computer scientists.

  20. Intelligent Agents in Physics Education

    NASA Astrophysics Data System (ADS)

    Sánchez-Guzmán, D.; Mora, César

    2010-07-01

    Intelligent Agents are being applied in a wide range of processes and everyday applications. Their development is not new, in recent years they have had an increased attention and design; like learning and mentoring tools. In this work we discuss the definition of what an intelligent agent is; how they are applied; how they look like; recent implementations of agents; agents as support in the learning process, more precisely intelligent tutors; their state in Latin-American countries and future developments and trends that will permit a better communication between people and agents. Also we present an Intelligent Tutor applied as a tool for improving high-school students' skills and reasoning for the first five topics of Mechanics curricula.

  1. Transdermal delivery of therapeutic agent

    NASA Technical Reports Server (NTRS)

    Kwiatkowski, Krzysztof C. (Inventor); Hayes, Ryan T. (Inventor); Magnuson, James W. (Inventor); Giletto, Anthony (Inventor)

    2008-01-01

    A device for the transdermal delivery of a therapeutic agent to a biological subject that includes a first electrode comprising a first array of electrically conductive microprojections for providing electrical communication through a skin portion of the subject to a second electrode comprising a second array of electrically conductive microprojections. Additionally, a reservoir for holding the therapeutic agent surrounding the first electrode and a pulse generator for providing an exponential decay pulse between the first and second electrodes may be provided. A method includes the steps of piercing a stratum corneum layer of skin with two arrays of conductive microprojections, encapsulating the therapeutic agent into biocompatible charged carriers, surrounding the conductive microprojections with the therapeutic agent, generating an exponential decay pulse between the two arrays of conductive microprojections to create a non-uniform electrical field and electrokinetically driving the therapeutic agent through the stratum corneum layer of skin.

  2. Markov Tracking for Agent Coordination

    NASA Technical Reports Server (NTRS)

    Washington, Richard; Lau, Sonie (Technical Monitor)

    1998-01-01

    Partially observable Markov decision processes (POMDPs) axe an attractive representation for representing agent behavior, since they capture uncertainty in both the agent's state and its actions. However, finding an optimal policy for POMDPs in general is computationally difficult. In this paper we present Markov Tracking, a restricted problem of coordinating actions with an agent or process represented as a POMDP Because the actions coordinate with the agent rather than influence its behavior, the optimal solution to this problem can be computed locally and quickly. We also demonstrate the use of the technique on sequential POMDPs, which can be used to model a behavior that follows a linear, acyclic trajectory through a series of states. By imposing a "windowing" restriction that restricts the number of possible alternatives considered at any moment to a fixed size, a coordinating action can be calculated in constant time, making this amenable to coordination with complex agents.

  3. Dietary agents for chemoprevention of prostate cancer

    PubMed Central

    Syed, Deeba N; Suh, Yewseok; Afaq, Farrukh; Mukhtar, Hasan

    2011-01-01

    Prostate cancer (CaP) is the leading cause of cancer-related deaths in American men, responsible for over 29,000 deaths in the year 2007. Chemoprevention is a plausible and cost-effective approach to reduce cancer morbidity and mortality through inhibition of precancerous events before the occurrence of clinical disease. Indeed, CaP is an ideal candidate disease for chemopreventive intervention as it is typically diagnosed in the elderly population with a relatively slower rate of growth and progression. The potential of dietary substances to act as chemopreventive agents against CaP is increasingly appreciated. Furhter, epidemiological studies have identified significant correlations between CaP incidence and dietary habits. It is hoped that, combining the knowledge based on agents with targets, we will be able to build an armamentarium of naturally occurring chemopreventive substances that could prevent or slow down the development and progression of CaP. In this review, we have summarized the findings from clinical and preclinical studies on dietary agents including green tea, pomegranate, lupeol, fisetin and delphinidin that are currently being investigated in our laboratory for their chemopreventive potential against CaP. PMID:18395333

  4. Differential mobility spectroscopy for chemical agent detection

    NASA Astrophysics Data System (ADS)

    Griffin, M. Todd

    2006-05-01

    General Dynamics ATP (GDATP) and Sionex Corporation (Sionex) are carrying out a cooperative development for a handheld chemical agent detector, being called JUNO TM, which will have lower false positives, higher sensitivity, and improved interference rejection compared with presently available detectors. This enhanced performance is made possible by the use of a new principle of ion separation called Differential Mobility Spectrometry (DMS). The enhanced selectivity is provided by the field tunable nature of the Sionex differential mobility technology (microDMxTM) which forms the analytical heart of the JUNO system and enables fingerprinting of molecules by characterization of the ionized molecular behavior under multiple electric field conditions. This enhanced selectivity is valuable in addressing not only the traditional list of chemical warfare agents (CWA) but also the substantial list of Toxic Industrial Compounds (TICs) and Toxic Industrial Materials (TIMs) which may be released in warfare or terrorist situations. Experimental results showing the ability of the microDMx to reject interferences, detect and resolve live agents are presented. An additional breakthrough in the technology was realized by operating the device at a reduced pressure of around 0.5 atmospheres. This reduced pressure operation resulted in roughly doubling the spectrometers resolution over what has previously been reported [1]. Advances have also been made in power consumption and packaging leading to a device suitable for portable, handheld, applications. Experimental results illustrating the performance of the microDMx technology employed in JUNO are highlighted.

  5. Discovery and development of new antimicrobial agents.

    PubMed Central

    Gootz, T D

    1990-01-01

    The unprecedented growth in the number of new antibiotics over the past two decades has been the result of extensive research efforts that have exploited the growing body of knowledge describing the interactions of antibiotics with their targets in bacterial cells. Information gained from one class of antimicrobial agents has often been used to advance the development of other classes. In the case of beta-lactams, information on structure-activity relationships gleaned from penicillins and cephalosporins was rapidly applied to the cephamycins, monobactams, penems, and carbapenems in order to discover broad-spectrum agents with markedly improved potency. These efforts have led to the introduction of many new antibiotics that demonstrate outstanding clinical efficacy and improved pharmacokinetics in humans. The current review discusses those factors that have influenced the rapid proliferation of new antimicrobial agents, including the discovery of new lead structures from natural products and the impact of bacterial resistance development in the clinical setting. The development process for a new antibiotic is discussed in detail, from the stage of early safety testing in animals through phase I, II, and III clinical trials. PMID:2404566

  6. Knowledge focus via software agents

    NASA Astrophysics Data System (ADS)

    Henager, Donald E.

    2001-09-01

    The essence of military Command and Control (C2) is making knowledge intensive decisions in a limited amount of time using uncertain, incorrect, or outdated information. It is essential to provide tools to decision-makers that provide: * Management of friendly forces by treating the "friendly resources as a system". * Rapid assessment of effects of military actions againt the "enemy as a system". * Assessment of how an enemy should, can, and could react to friendly military activities. Software agents in the form of mission agents, target agents, maintenance agents, and logistics agents can meet this information challenge. The role of each agent is to know all the details about its assigned mission, target, maintenance, or logistics entity. The Mission Agent would fight for mission resources based on the mission priority and analyze the effect that a proposed mission's results would have on the enemy. The Target Agent (TA) communicates with other targets to determine its role in the system of targets. A system of TAs would be able to inform a planner or analyst of the status of a system of targets, the effect of that status, adn the effect of attacks on that system. The system of TAs would also be able to analyze possible enemy reactions to attack by determining ways to minimize the effect of attack, such as rerouting traffic or using deception. The Maintenance Agent would scheudle maintenance events and notify the maintenance unit. The Logistics Agent would manage shipment and delivery of supplies to maintain appropriate levels of weapons, fuel and spare parts. The central idea underlying this case of software agents is knowledge focus. Software agents are createad automatically to focus their attention on individual real-world entities (e.g., missions, targets) and view the world from that entities perspective. The agent autonomously monitors the entity, identifies problems/opportunities, formulates solutions, and informs the decision-maker. The agent must be

  7. Contrast agents for cardiac angiography: effects of a nonionic agent vs. a standard ionic agent

    SciTech Connect

    Bettmann, M.A.; Bourdillon, P.D.; Barry, W.H.; Brush, K.A.; Levin, D.C.

    1984-12-01

    The effects on cardiac hemodynamics and of a standard contrast agent, sodium methylglucamine diatrizoate (Renografin 76) were compared with the effects of a new nonionic agent (iohexol) in a double-blind study in 51 patietns undergoing coronary angiography and left ventriculography. No significant alteration in measured blood parameters occurred with either contrast agent. Hemodynamic changes occurred with both, but were significantly greater with the standard renografin than with the low-osmolality, nonionic iohexol. After left ventriculography, heart rate increased and peripheral arterial pressure fell with both agents, but less with iohexol. It is concluded that iohexol causes less alteration in cardiac function than does the agent currently most widely used. Nonionic contrast material is likely to improve the safety of coronary angiography, particularly in those patients at greatest risk.

  8. Agent Communications using Distributed Metaobjects

    SciTech Connect

    Goldsmith, Steven Y.; Spires, Shannon V.

    1999-06-10

    There are currently two proposed standards for agent communication languages, namely, KQML (Finin, Lobrou, and Mayfield 1994) and the FIPA ACL. Neither standard has yet achieved primacy, and neither has been evaluated extensively in an open environment such as the Internet. It seems prudent therefore to design a general-purpose agent communications facility for new agent architectures that is flexible yet provides an architecture that accepts many different specializations. In this paper we exhibit the salient features of an agent communications architecture based on distributed metaobjects. This architecture captures design commitments at a metaobject level, leaving the base-level design and implementation up to the agent developer. The scope of the metamodel is broad enough to accommodate many different communication protocols, interaction protocols, and knowledge sharing regimes through extensions to the metaobject framework. We conclude that with a powerful distributed object substrate that supports metaobject communications, a general framework can be developed that will effectively enable different approaches to agent communications in the same agent system. We have implemented a KQML-based communications protocol and have several special-purpose interaction protocols under development.

  9. Amaryllidaceae Isocarbostyril Alkaloids and Their Derivatives as Promising Antitumor Agents

    PubMed Central

    Ingrassia, Laurent; Lefranc, Florence; Mathieu, Véronique; Darro, Francis; Kiss, Robert

    2008-01-01

    This review covers the isolation, total synthesis, biologic activity, and more particularly the in vitro and in vivo antitumor activities of naturally occurring isocarbostyril alkaloids from the Amaryllidaceae family. Starting from these natural products, new derivatives have been synthesized to explore structure-activity relationships within the chemical class and to obtain potential candidates for preclinical development. This approach appears to be capable of providing novel promising anticancer agents. PMID:18607503

  10. Departments as Agents of Change

    NASA Astrophysics Data System (ADS)

    Lagowski, J. J.

    1996-07-01

    Higher education is changing because it has no choice. And, for the most part, outside influences are dictating the processes of change. The more fortunate institutions have had a flat budget during this period, but most have been forced to deal with a declining revenue stream as well. Legislators seem bent on micromanaging state-supported institutions, even as they cut their support. Regulators demand greater institutional accountability. Students and their parents expect more service at lower prices and increased flexibility. Technological advances have dramatically affected the availability and accessibility of extant knowledge. It is no longer a question of whether institutions will change, but rather, who will control the change. Most institutions possess long-standing academic traditions, but these are placed at risk in an increasingly competitive market that holds little sympathy for such traditions and may even see them as obstacles or barriers. As a result, the change agents will undoubtedly have a profound effect on the very nature of academic institutions. From the academic point of view, it would seem prudent to attempt to manage the changes that will inevitably occur. A number of concerned observers, notably the Pew Higher Education Roundtable and the American Association for Higher Education, argue persuasively that the academic department is the logical focus for responding to the current winds of change. Using a marketing metaphor, the academic department has been likened to a "producers' cooperative" of services that consumers seek. Thus, the department should be held accountable for the quality of teaching delivered by its members, for the coherence of its major, for its contributions to the general education curriculum, and for supervising and rewarding its individual faculty members. If departments are to be held accountable, it is surely in their best interest to act in such a way that they are accountable. Expecting academic departments to be

  11. Natural products: DNA double whammy

    NASA Astrophysics Data System (ADS)

    Gates, Kent S.

    2014-06-01

    The lomaiviticins are exceedingly potent antibiotic agents, but the mechanism responsible for this activity has so far been unclear. Now, efficient generation of double-strand breaks in DNA by lomaiviticin A has been linked to the remarkable cytotoxicity of these diazobenzofluorene-containg natural products.

  12. A Cybernetic Approach to the Modeling of Agent Communities

    NASA Technical Reports Server (NTRS)

    Truszkowski, Walt; Karlin, Jay

    2000-01-01

    In an earlier paper [1] examples of agent technology in a NASA context were presented. Both groundbased and space-based applications were addressed. This paper continues the discussion of one aspect of the Goddard Space Flight Center's continuing efforts to develop a community of agents that can support both ground-based and space-based systems autonomy. The paper focuses on an approach to agent-community modeling based on the theory of viable systems developed by Stafford Beer. It gives the status of an initial attempt to capture some of the agent-community behaviors in a viable system context. This paper is expository in nature and focuses on a discussion of the modeling of some of the underlying concepts and infrastructure that will serve as the basis of more detailed investigative work into the behavior of agent communities. The paper is organized as follows. First, a general introduction to agent community requirements is presented. Secondly, a brief introduction to the cybernetic concept of a viable system is given. This concept forms the foundation of the modeling approach. Then the concept of an agent community is modeled in the cybernetic context.

  13. Evaluation of risedronate as an antibiofilm agent.

    PubMed

    Reshamwala, Shamlan M S; Mamidipally, Chandrasekhar; Pissurlenkar, Raghuvir R S; Coutinho, Evans C; Noronha, Santosh B

    2016-01-01

    Escherichia coli cra null mutants have been reported in the literature to be impaired in biofilm formation. To develop E. coli biofilm-inhibiting agents for prevention and control of adherent behaviour, analogues of a natural Cra ligand, fructose-1,6-bisphosphate, were identified based on two-dimensional similarity to the natural ligand. Of the analogues identified, those belonging to the bisphosphonate class of drug molecules were selected for study, as these are approved for clinical use in humans and their safety has been established. Computational and in vitro studies with purified Cra protein showed that risedronate sodium interacted with residues in the fructose-1,6-bisphosphate-binding site. Using a quantitative biofilm assay, risedronate sodium, at a concentration of 300-400 μM, was found to decrease E. coli and Salmonella pullorum biofilm formation by >60 %. Risedronate drastically reduced the adherence of E. coli cells to a rubber Foley urinary catheter, demonstrating its utility in preventing the formation of biofilm communities on medical implant surfaces. The use of risedronate, either alone or in combination with other agents, to prevent the formation of biofilms on surfaces is a novel finding that can easily be translated into practical applications. PMID:26497196

  14. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

    1997-12-30

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.

  15. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, Paul H.; Brainard, James R.; Jarvinen, Gordon D.; Ryan, Robert R.

    1997-01-01

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC.sub.16 H.sub.14 N.sub.6. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques.

  16. Antibacterial agents in the cinema.

    PubMed

    García Sánchez, J E; García Sánchez, E; Merino Marcos, M L

    2006-12-01

    Numerous procedures used as antibacterial therapy are present in many films and include strategies ranging from different antimicrobial drugs to surgery and supporting measures. Films also explore the correct use and misuse of antimicrobial agents. Side effects and other aspects related to antibacterial therapy have also been reflected in some films. This article refers to the presence of antibacterial agents in different popular movies. There are movies in which antibacterial agents form part of the central plot, while in others it is merely an important part of the plot. In still others, its presence is isolated, and in these it plays an ambient or anecdotal role.

  17. Provocative agents in panic disorder.

    PubMed

    Bourin, M; Malinge, M; Guitton, B

    1995-01-01

    The pharmacological challenge strategy involves giving a provoking agent under controlled rules to clarify some aspect of behavioural or biological function. Various agents such as sodium lactate, carbon dioxide, caffeine, yohimbine, isoprenaline and now cholecystokinin have been used as provoking agents in healthy volunteers as well as in panic patients. Results obtained in this field are updated, with emphasis on the potential mechanisms of action. It is concluded that there may be a final pathway between carbon dioxide, sodium lactate, and cholecystokinin inducing panic attacks.

  18. Enhancement of Commercial Antifungal Agents by Kojic Acid

    PubMed Central

    Kim, Jong H.; Chang, Perng-Kuang; Chan, Kathleen L.; Faria, Natália C. G.; Mahoney, Noreen; Kim, Young K.; Martins, Maria de L.; Campbell, Bruce C.

    2012-01-01

    Natural compounds that pose no significant medical or environmental side effects are potential sources of antifungal agents, either in their nascent form or as structural backbones for more effective derivatives. Kojic acid (KA) is one such compound. It is a natural by-product of fungal fermentation commonly employed by food and cosmetic industries. We show that KA greatly lowers minimum inhibitory (MIC) or fungicidal (MFC) concentrations of commercial medicinal and agricultural antifungal agents, amphotericin B (AMB) and strobilurin, respectively, against pathogenic yeasts and filamentous fungi. Assays using two mitogen-activated protein kinase (MAPK) mutants, i.e., sakAΔ, mpkCΔ, of Aspergillus fumigatus, an agent for human invasive aspergillosis, with hydrogen peroxide (H2O2) or AMB indicate such chemosensitizing activity of KA is most conceivably through disruption of fungal antioxidation systems. KA could be developed as a chemosensitizer to enhance efficacy of certain conventional antifungal drugs or fungicides. PMID:23203038

  19. Betacyanins pigments as photosensitizing agents for holographic recording medium

    NASA Astrophysics Data System (ADS)

    Toxqui-López, S.; Hernández-Hernández, E.; Santacruz-Vázquez, C.; Olivares-Pérez, A.; Santacruz-Vazquez, V.

    2014-02-01

    One of the natural most employed within the food industry are pigments of betalains by their solubility in water to give desired colorations in processed foods such as beverages, dairy, meat. However, this research shows that this type of pigments can be used as photosensitizing agents in the field of holographic recording materials.

  20. An Agent-Based Interface to Terrestrial Ecological Forecasting

    NASA Technical Reports Server (NTRS)

    Golden, Keith; Nemani, Ramakrishna; Pang, Wan-Lin; Votava, Petr; Etzioni, Oren

    2004-01-01

    This paper describes a flexible agent-based ecological forecasting system that combines multiple distributed data sources and models to provide near-real-time answers to questions about the state of the Earth system We build on novel techniques in automated constraint-based planning and natural language interfaces to automatically generate data products based on descriptions of the desired data products.

  1. The agent-based spatial information semantic grid

    NASA Astrophysics Data System (ADS)

    Cui, Wei; Zhu, YaQiong; Zhou, Yong; Li, Deren

    2006-10-01

    Analyzing the characteristic of multi-Agent and geographic Ontology, The concept of the Agent-based Spatial Information Semantic Grid (ASISG) is defined and the architecture of the ASISG is advanced. ASISG is composed with Multi-Agents and geographic Ontology. The Multi-Agent Systems are composed with User Agents, General Ontology Agent, Geo-Agents, Broker Agents, Resource Agents, Spatial Data Analysis Agents, Spatial Data Access Agents, Task Execution Agent and Monitor Agent. The architecture of ASISG have three layers, they are the fabric layer, the grid management layer and the application layer. The fabric layer what is composed with Data Access Agent, Resource Agent and Geo-Agent encapsulates the data of spatial information system so that exhibits a conceptual interface for the Grid management layer. The Grid management layer, which is composed with General Ontology Agent, Task Execution Agent and Monitor Agent and Data Analysis Agent, used a hybrid method to manage all resources that were registered in a General Ontology Agent that is described by a General Ontology System. The hybrid method is assembled by resource dissemination and resource discovery. The resource dissemination push resource from Local Ontology Agent to General Ontology Agent and the resource discovery pull resource from the General Ontology Agent to Local Ontology Agents. The Local Ontology Agent is derived from special domain and describes the semantic information of local GIS. The nature of the Local Ontology Agents can be filtrated to construct a virtual organization what could provides a global scheme. The virtual organization lightens the burdens of guests because they need not search information site by site manually. The application layer what is composed with User Agent, Geo-Agent and Task Execution Agent can apply a corresponding interface to a domain user. The functions that ASISG should provide are: 1) It integrates different spatial information systems on the semantic The Grid

  2. Agent-based forward analysis

    SciTech Connect

    Kerekes, Ryan A.; Jiao, Yu; Shankar, Mallikarjun; Potok, Thomas E.; Lusk, Rick M.

    2008-01-01

    We propose software agent-based "forward analysis" for efficient information retrieval in a network of sensing devices. In our approach, processing is pushed to the data at the edge of the network via intelligent software agents rather than pulling data to a central facility for processing. The agents are deployed with a specific query and perform varying levels of analysis of the data, communicating with each other and sending only relevant information back across the network. We demonstrate our concept in the context of face recognition using a wireless test bed comprised of PDA cell phones and laptops. We show that agent-based forward analysis can provide a significant increase in retrieval speed while decreasing bandwidth usage and information overload at the central facility. n

  3. Triggered pore-forming agents

    DOEpatents

    Bayley, Hagan; Walker, Barbara J.; Chang, Chung-yu; Niblack, Brett; Panchal, Rekha

    1998-01-01

    An inactive pore-forming agent which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell.

  4. AL Amyloidosis and Agent Orange

    MedlinePlus

    ... for survivors' benefits . Research on AL amyloidosis and herbicides The Health and Medicine Division (formally known as ... to the compounds of interest found in the herbicide Agent Orange and AL amyloidosis." VA made a ...

  5. Diamine curing agents for polyurethanes

    NASA Technical Reports Server (NTRS)

    Bell, V. L.; St. Clair, T. L.

    1975-01-01

    Three aromatic diamines have properties that make them promising candidates as curing agents for converting isocyanates to polyurethanes with higher adhesive strengths, higher softening temperatures, better toughness, and improved abrasion resistance.

  6. Launch Commit Criteria Monitoring Agent

    NASA Technical Reports Server (NTRS)

    Semmel, Glenn S.; Davis, Steven R.; Leucht, Kurt W.; Rowe, Dan A.; Kelly, Andrew O.; Boeloeni, Ladislau

    2005-01-01

    The Spaceport Processing Systems Branch at NASA Kennedy Space Center has developed and deployed a software agent to monitor the Space Shuttle's ground processing telemetry stream. The application, the Launch Commit Criteria Monitoring Agent, increases situational awareness for system and hardware engineers during Shuttle launch countdown. The agent provides autonomous monitoring of the telemetry stream, automatically alerts system engineers when predefined criteria have been met, identifies limit warnings and violations of launch commit criteria, aids Shuttle engineers through troubleshooting procedures, and provides additional insight to verify appropriate troubleshooting of problems by contractors. The agent has successfully detected launch commit criteria warnings and violations on a simulated playback data stream. Efficiency and safety are improved through increased automation.

  7. Noncontraceptive use of contraceptive agents.

    PubMed

    Nickles, Monique Collier; Alderman, Elizabeth

    2014-06-01

    • On the basis of strong research evidence, there are many noncontraceptive advantages to use of hormonal contraceptive agents in adolescent girls. (3) (4)(5)(7)(10)(11)(12)(13)(14). • On the basis of research evidence and consensus, most of these agents are safe with minor adverse effects. (2)(3)(4)(5)(7)(10)(11)(12)(13)(14). • On the basis of research evidence and consensus, through application of evidence-based approaches and proper counseling, pediatricians can use various contraceptive agents to treat several medical conditions and to help alleviate many of the undesired symptoms and complications associated with menstrual periods. (2)(3)(4)(5)(7)(10)(11)(12)(13) (14). • On the basis of research evidence and consensus, these agents may be used in sexually active adolescents to simultaneously help prevent unintended adolescent pregnancies. (2)(3)(4)(5)(7)(10)(11)(12)(13)(14).

  8. Microbial Resistance to Triclosan: A Case Study in Natural Selection

    ERIC Educational Resources Information Center

    Serafini, Amanda; Matthews, Dorothy M.

    2009-01-01

    Natural selection is the mechanism of evolution caused by the environmental selection of organisms most fit to reproduce, sometimes explained as "survival of the fittest." An example of evolution by natural selection is the development of bacteria that are resistant to antimicrobial agents as a result of exposure to these agents. Triclosan, which…

  9. Antimicrobials for bacterial bioterrorism agents.

    PubMed

    Sarkar-Tyson, Mitali; Atkins, Helen S

    2011-06-01

    The limitations of current antimicrobials for highly virulent pathogens considered as potential bioterrorism agents drives the requirement for new antimicrobials that are suitable for use in populations in the event of a deliberate release. Strategies targeting bacterial virulence offer the potential for new countermeasures to combat bacterial bioterrorism agents, including those active against a broad spectrum of pathogens. Although early in the development of antivirulence approaches, inhibitors of bacterial type III secretion systems and cell division mechanisms show promise for the future.

  10. Ramucirumab: a novel antiangiogenic agent.

    PubMed

    Wadhwa, Roopma; Taketa, Takashi; Sudo, Kazuki; Blum-Murphy, Mariela; Ajani, Jaffer A

    2013-06-01

    Ramucirumab (IMC-1121B) is a fully humanized monoclonal antibody that binds to VEGFR2 and can inhibit angiogenesis, a quintessential mechanism for promoting tumor growth and metastasis. Several antiangiogenesis agents are already approved for cancer therapy; however, ramucirumab's selectivity for VEGFR2 makes it interesting. The selectivity of an agent can improve safety and efficacy. This article describes the mechanism of action, pharmacokinetics, safety and clinical trial results of ramucirumab with particular emphasis on gastric cancer.

  11. What makes virtual agents believable?

    NASA Astrophysics Data System (ADS)

    Bogdanovych, Anton; Trescak, Tomas; Simoff, Simeon

    2016-01-01

    In this paper we investigate the concept of believability and make an attempt to isolate individual characteristics (features) that contribute to making virtual characters believable. As the result of this investigation we have produced a formalisation of believability and based on this formalisation built a computational framework focused on simulation of believable virtual agents that possess the identified features. In order to test whether the identified features are, in fact, responsible for agents being perceived as more believable, we have conducted a user study. In this study we tested user reactions towards the virtual characters that were created for a simulation of aboriginal inhabitants of a particular area of Sydney, Australia in 1770 A.D. The participants of our user study were exposed to short simulated scenes, in which virtual agents performed some behaviour in two different ways (while possessing a certain aspect of believability vs. not possessing it). The results of the study indicate that virtual agents that appear resource bounded, are aware of their environment, own interaction capabilities and their state in the world, agents that can adapt to changes in the environment and exist in correct social context are those that are being perceived as more believable. Further in the paper we discuss these and other believability features and provide a quantitative analysis of the level of contribution for each such feature to the overall perceived believability of a virtual agent.

  12. Fused xanthone derivatives as antiproliferative agents.

    PubMed

    Pouli, Nicole; Marakos, Panagiotis

    2009-01-01

    Xanthones have been isolated from several natural sources, mainly belonging in Guttiferae and Gentianaceae families as secondary plant metabolites and many of them are endowed with diverse pharmacological properties. We have focused in the study of cytotoxic fused xanthone derivatives, having in mind that some furano- and pyranoxanthone natural products are particularly interesting, in terms of cytotoxic potency and novelty in their mechanism of action and could serve as lead compounds for the development of clinically effective anticancer agents. In this review, a general classification has been attempted based on the type of ring fusion, in such a way that natural compounds as well as synthetic derivatives are discussed. The furanoxanthone psorospermin is a highly promising isolated xanthone derivative exhibiting significant cytotoxicity through a novel mechanism of action, being an irreversible topoisomerase II poison and it was selected for further development as an antineoplastic agent. An important number of pyranoxanthones have been synthesized using as lead compound the acridone alkaloid acronycine. Adducts on the double bond of these compounds provided cytotoxic derivatives possessing cell-cycle selectivity. The synthesis of pyranoxanthones bearing aminosubstituted side-chains resulted in compounds that exhibit markedly improved cytotoxicity towards leukemic and solid tumor cell lines. Azabioisosters of the aminoderivatives exhibit solid tumor selectivity whereas additional pyrazole or/and benzene ring fusion has been incorporated into the xanthone skeleton and resulted in compounds with promising activity, which retain full antiproliferative activity against P-glycoprotein-overexpressing cells. Gambogic acid, a highly effective anticancer drug candidate with low toxicity to normal tissue, together with structurally related representative analogues are also mentioned. PMID:19149484

  13. Hybrid evolutionary computing model for mobile agents of wireless Internet multimedia

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    2001-03-01

    The ecosystem is used as an evolutionary paradigm of natural laws for the distributed information retrieval via mobile agents to allow the computational load to be added to server nodes of wireless networks, while reducing the traffic on communication links. Based on the Food Web model, a set of computational rules of natural balance form the outer stage to control the evolution of mobile agents providing multimedia services with a wireless Internet protocol WIP. The evolutionary model shows how mobile agents should behave with the WIP, in particular, how mobile agents can cooperate, compete and learn from each other, based on an underlying competition for radio network resources to establish the wireless connections to support the quality of service QoS of user requests. Mobile agents are also allowed to clone themselves, propagate and communicate with other agents. A two-layer model is proposed for agent evolution: the outer layer is based on the law of natural balancing, the inner layer is based on a discrete version of a Kohonen self-organizing feature map SOFM to distribute network resources to meet QoS requirements. The former is embedded in the higher OSI layers of the WIP, while the latter is used in the resource management procedures of Layer 2 and 3 of the protocol. Algorithms for the distributed computation of mobile agent evolutionary behavior are developed by adding a learning state to the agent evolution state diagram. When an agent is in an indeterminate state, it can communicate to other agents. Computing models can be replicated from other agents. Then the agents transitions to the mutating state to wait for a new information-retrieval goal. When a wireless terminal or station lacks a network resource, an agent in the suspending state can change its policy to submit to the environment before it transitions to the searching state. The agents learn the facts of agent state information entered into an external database. In the cloning process, two

  14. A multi-agent architecture for geosimulation of moving agents

    NASA Astrophysics Data System (ADS)

    Vahidnia, Mohammad H.; Alesheikh, Ali A.; Alavipanah, Seyed Kazem

    2015-10-01

    In this paper, a novel architecture is proposed in which an axiomatic derivation system in the form of first-order logic facilitates declarative explanation and spatial reasoning. Simulation of environmental perception and interaction between autonomous agents is designed with a geographic belief-desire-intention and a request-inform-query model. The architecture has a complementary quantitative component that supports collaborative planning based on the concept of equilibrium and game theory. This new architecture presents a departure from current best practices geographic agent-based modelling. Implementation tasks are discussed in some detail, as well as scenarios for fleet management and disaster management.

  15. An Exploratory Study on How Children Interact with Pedagogic Conversational Agents

    ERIC Educational Resources Information Center

    Pérez-Marín, Diana; Pascual-Nieto, Ismael

    2013-01-01

    A pedagogic conversational agent (PCA) can be defined as a computer system that interacts with the student in natural language assuming the role of the instructor, a student or a companion. It can have a personality and can generate different sentences according to the agent or the student mood. Empathy with the students' feelings seems to…

  16. In-Service Training of Agricultural Agents in New York State: 1963; Extension Study Number 6.

    ERIC Educational Resources Information Center

    Alexander, Frank D.; Harshaw, Jean

    The purpose of this study was to ascertain the nature and amount of inservice training which the 168 agricultural agents in New York State received during 1963. Emphasis was on refresher and other training. The greatest number of days of training offered agents was in November followed closely by March and February, in all, a total of 36% of the…

  17. Relationship between Assessment Center Performance and Psychological Types of Cooperative Extension Agents in Ohio.

    ERIC Educational Resources Information Center

    Ishaya, Joseph B.; And Others

    1992-01-01

    The Myers-Briggs Type Inventory was completed by 135 cooperative extension agents who attended an assessment center. The majority were extroverts with sensing, thinking, and judging preferences. Those in administration or community/natural resources or with more experience had higher assessment center scores. Perceiving-oriented agents had lower…

  18. Chemosensitization as a Means to Augment Commercial Antifungal Agents

    PubMed Central

    Campbell, Bruce C.; Chan, Kathleen L.; Kim, Jong H.

    2012-01-01

    Antimycotic chemosensitization and its mode of action are of growing interest. Currently, use of antifungal agents in agriculture and medicine has a number of obstacles. Foremost of these is development of resistance or cross-resistance to one or more antifungal agents. The generally high expense and negative impact, or side effects, associated with antifungal agents are two further issues of concern. Collectively, these problems are exacerbated by efforts to control resistant strains, which can evolve into a treadmill of higher dosages for longer periods. This cycle in turn, inflates cost of treatment, dramatically. A further problem is stagnation in development of new and effective antifungal agents, especially for treatment of human mycoses. Efforts to overcome some of these issues have involved using combinations of available antimycotics (e.g., combination therapy for invasive mycoses). However, this approach has had inconsistent success and is often associated with a marked increase in negative side effects. Chemosensitization by natural compounds to increase effectiveness of commercial antimycotics is a somewhat new approach to dealing with the aforementioned problems. The potential for safe natural products to improve antifungal activity has been observed for over three decades. Chemosensitizing agents possess antifungal activity, but at insufficient levels to serve as antimycotics, alone. Their main function is to disrupt fungal stress response, destabilize the structural integrity of cellular and vacuolar membranes or stimulate production of reactive oxygen species, augmenting oxidative stress and apoptosis. Use of safe chemosensitizing agents has potential benefit to both agriculture and medicine. When co-applied with a commercial antifungal agent, an additive or synergistic interaction may occur, augmenting antifungal efficacy. This augmentation, in turn, lowers effective dosages, costs, negative side effects and, in some cases, countermands resistance

  19. Next Generation Remote Agent Planner

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari K.; Muscettola, Nicola; Morris, Paul H.; Rajan, Kanna

    1999-01-01

    In May 1999, as part of a unique technology validation experiment onboard the Deep Space One spacecraft, the Remote Agent became the first complete autonomous spacecraft control architecture to run as flight software onboard an active spacecraft. As one of the three components of the architecture, the Remote Agent Planner had the task of laying out the course of action to be taken, which included activities such as turning, thrusting, data gathering, and communicating. Building on the successful approach developed for the Remote Agent Planner, the Next Generation Remote Agent Planner is a completely redesigned and reimplemented version of the planner. The new system provides all the key capabilities of the original planner, while adding functionality, improving performance and providing a modular and extendible implementation. The goal of this ongoing project is to develop a system that provides both a basis for future applications and a framework for further research in the area of autonomous planning for spacecraft. In this article, we present an introductory overview of the Next Generation Remote Agent Planner. We present a new and simplified definition of the planning problem, describe the basics of the planning process, lay out the new system design and examine the functionality of the core reasoning module.

  20. Investigational Antimicrobial Agents of 2013

    PubMed Central

    Pucci, Michael J.

    2013-01-01

    SUMMARY New antimicrobial agents are always needed to counteract the resistant pathogens that continue to be selected by current therapeutic regimens. This review provides a survey of known antimicrobial agents that were currently in clinical development in the fall of 2012 and spring of 2013. Data were collected from published literature primarily from 2010 to 2012, meeting abstracts (2011 to 2012), government websites, and company websites when appropriate. Compared to what was reported in previous surveys, a surprising number of new agents are currently in company pipelines, particularly in phase 3 clinical development. Familiar antibacterial classes of the quinolones, tetracyclines, oxazolidinones, glycopeptides, and cephalosporins are represented by entities with enhanced antimicrobial or pharmacological properties. More importantly, compounds of novel chemical structures targeting bacterial pathways not previously exploited are under development. Some of the most promising compounds include novel β-lactamase inhibitor combinations that target many multidrug-resistant Gram-negative bacteria, a critical medical need. Although new antimicrobial agents will continue to be needed to address increasing antibiotic resistance, there are novel agents in development to tackle at least some of the more worrisome pathogens in the current nosocomial setting. PMID:24092856

  1. Killer clays! Natural antibacterial clay minerals

    USGS Publications Warehouse

    Williams, L.B.; Holland, M.; Eberl, D.D.; Brunet, T.; De Courrsou, L. B.

    2004-01-01

    The clay chemical properties that may be important in medicine were investigated. It was found that natural clay minerals can have striking and very specific effects on microbial populations. The effects can range from potentially enhanced microbial growth to complete sterilization. This paper presents evidence that natural clay minerals can be effective antimicrobial agents.

  2. Temporal naturalism

    NASA Astrophysics Data System (ADS)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  3. Latest Trend of Object Oriented Technology and Agent Technology

    NASA Astrophysics Data System (ADS)

    Nakatani, Takako; Hanyuda, Eiiti; Kurokawa, Toshiaki; Suguta, Shigeki; Ohsuga, Akihiko; Kodama, Kiminobu; Masumura, Hitoshi; Nakamura, Masatoshi; Tanaka, Tatsuji

    Object-oriented technology is used for the software of the large range, and its application fields are increasing. Object-oriented technology is also accepted naturally in the field of Internet application. Consequently, developments of new kinds of object-oriented technologies have been performed. Agent technology has been developed based on an object-oriented concept, and may have a great evolution with applying to applications of Internet field. In this paper, authors introduce the latest trend and the example of application of such object-oriented technology and agent technology.

  4. Therapeutic agents and herbs in topical application for acne treatment.

    PubMed

    Kanlayavattanakul, M; Lourith, N

    2011-08-01

    Acne vulgaris suppresses an individual's self-confidence by causing distress with regard to physical appearance, which affects a significant number of individuals during puberty and is delineated by adolescence. Several treatments have been introduced to decrease the aesthetic and psychological problems caused by acne. The topical application of therapeutic agents has been found to be more feasible than hormonal treatment and laser therapy. The ingredients in topical acne treatments, particularly herbs and naturally derived compounds, have received considerable interest as they have fewer adverse effects than synthetic agents. PMID:21401650

  5. Improving Access To Novel Agents For Childhood Leukemia

    PubMed Central

    Sun, Weili; Gaynon, Paul S.; Sposto, Richard; Wayne, Alan S.

    2015-01-01

    Leukemia is the most common pediatric cancer. Despite great progress in the development of curative therapy, leukemia remains a leading cause of death from disease in childhood and survivors are at life-long risk of complications of treatment. New agents are needed to further increase cure rates and decrease treatment-associated toxicities. The complex biology and aggressive nature of childhood leukemia, coupled with the relatively small patient population available for study, pose specific challenges to the development of new therapies. In this review, we discuss strategies and initiatives designed to improve access to new agents in the treatment of pediatric leukemia. PMID:25678105

  6. Complex groundwater flow systems as traveling agent models.

    PubMed

    López Corona, Oliver; Padilla, Pablo; Escolero, Oscar; González, Tomas; Morales-Casique, Eric; Osorio-Olvera, Luis

    2014-01-01

    Analyzing field data from pumping tests, we show that as with many other natural phenomena, groundwater flow exhibits complex dynamics described by 1/f power spectrum. This result is theoretically studied within an agent perspective. Using a traveling agent model, we prove that this statistical behavior emerges when the medium is complex. Some heuristic reasoning is provided to justify both spatial and dynamic complexity, as the result of the superposition of an infinite number of stochastic processes. Even more, we show that this implies that non-Kolmogorovian probability is needed for its study, and provide a set of new partial differential equations for groundwater flow. PMID:25337455

  7. The Agent of extracting Internet Information with Lead Order

    NASA Astrophysics Data System (ADS)

    Mo, Zan; Huang, Chuliang; Liu, Aijun

    In order to carry out e-commerce better, advanced technologies to access business information are in need urgently. An agent is described to deal with the problems of extracting internet information that caused by the non-standard and skimble-scamble structure of Chinese websites. The agent designed includes three modules which respond to the process of extracting information separately. A method of HTTP tree and a kind of Lead algorithm is proposed to generate a lead order, with which the required web can be retrieved easily. How to transform the extracted information structuralized with natural language is also discussed.

  8. Complex groundwater flow systems as traveling agent models

    PubMed Central

    Padilla, Pablo; Escolero, Oscar; González, Tomas; Morales-Casique, Eric; Osorio-Olvera, Luis

    2014-01-01

    Analyzing field data from pumping tests, we show that as with many other natural phenomena, groundwater flow exhibits complex dynamics described by 1/f power spectrum. This result is theoretically studied within an agent perspective. Using a traveling agent model, we prove that this statistical behavior emerges when the medium is complex. Some heuristic reasoning is provided to justify both spatial and dynamic complexity, as the result of the superposition of an infinite number of stochastic processes. Even more, we show that this implies that non-Kolmogorovian probability is needed for its study, and provide a set of new partial differential equations for groundwater flow. PMID:25337455

  9. Relational agents in clinical psychiatry.

    PubMed

    Bickmore, Timothy; Gruber, Amanda

    2010-01-01

    Relational agents are computational artifacts, such as animated, screen-based characters or social robots, that are designed to establish a sense of rapport, trust, and even therapeutic alliance with patients, using ideal therapeutic relationships between human counselors and patients as role models. We describe the development and evaluation of several such agents designed for health counseling and behavioral-change interventions, in which a therapeutic alliance is established with patients in order to enhance the efficacy of the intervention. We also discuss the promise of using such agents as adjuncts to clinical psychiatry, a range of possible applications, and some of the challenges and ethical issues in developing and fielding them in psychiatric interventions.

  10. Haloprogin: a Topical Antifungal Agent

    PubMed Central

    Harrison, E. F.; Zwadyk, P.; Bequette, R. J.; Hamlow, E. E.; Tavormina, P. A.; Zygmunt, W. A.

    1970-01-01

    Haloprogin was shown to be a highly effective agent for the treatment of experimentally induced topical mycotic infections in guinea pigs. Its in vitro spectrum of activity also includes yeasts, yeastlike fungi (Candida species), and certain gram-positive bacteria. The in vitro and in vivo antifungal activity of haloprogin against dermatophytes was equal to that observed with tolnaftate. The striking differences between the two agents were the marked antimonilial and selective antibacterial activities shown by haloprogin, contrasted with the negligible activities found with tolnaftate. Addition of serum decreased the in vitro antifungal activity of haloprogin to a greater extent than that of tolnaftate; however, diminished antifungal activity was not observed when haloprogin was applied topically to experimental dermatophytic infections. Based on its broad spectrum of antimicrobial activity, haloprogin may prove to be a superior topical agent in the treatment of dermatophytic and monilial infections in man. PMID:5422306

  11. Dual Rationality and Deliberative Agents

    NASA Astrophysics Data System (ADS)

    Debenham, John; Sierra, Carles

    Human agents deliberate using models based on reason for only a minute proportion of the decisions that they make. In stark contrast, the deliberation of artificial agents is heavily dominated by formal models based on reason such as game theory, decision theory and logic—despite that fact that formal reasoning will not necessarily lead to superior real-world decisions. Further the Nobel Laureate Friedrich Hayek warns us of the ‘fatal conceit’ in controlling deliberative systems using models based on reason as the particular model chosen will then shape the system’s future and either impede, or eventually destroy, the subtle evolutionary processes that are an integral part of human systems and institutions, and are crucial to their evolution and long-term survival. We describe an architecture for artificial agents that is founded on Hayek’s two rationalities and supports the two forms of deliberation used by mankind.

  12. Polycatechol Nanoparticle MRI Contrast Agents.

    PubMed

    Li, Yiwen; Huang, Yuran; Wang, Zhao; Carniato, Fabio; Xie, Yijun; Patterson, Joseph P; Thompson, Matthew P; Andolina, Christopher M; Ditri, Treffly B; Millstone, Jill E; Figueroa, Joshua S; Rinehart, Jeffrey D; Scadeng, Miriam; Botta, Mauro; Gianneschi, Nathan C

    2016-02-01

    Amphiphilic triblock copolymers containing Fe(III) -catecholate complexes formulated as spherical- or cylindrical-shaped micellar nanoparticles (SMN and CMN, respectively) are described as new T1-weighted agents with high relaxivity, low cytotoxicity, and long-term stability in biological fluids. Relaxivities of both SMN and CMN exceed those of established gadolinium chelates across a wide range of magnetic field strengths. Interestingly, shape-dependent behavior is observed in terms of the particles' interactions with HeLa cells, with CMN exhibiting enhanced uptake and contrast via magnetic resonance imaging (MRI) compared with SMN. These results suggest that control over soft nanoparticle shape will provide an avenue for optimization of particle-based contrast agents as biodiagnostics. The polycatechol nanoparticles are proposed as suitable for preclinical investigations into their viability as gadolinium-free, safe, and effective imaging agents for MRI contrast enhancement. PMID:26681255

  13. Agent review phase one report.

    SciTech Connect

    Zubelewicz, Alex Tadeusz; Davis, Christopher Edward; Bauer, Travis LaDell

    2009-12-01

    This report summarizes the findings for phase one of the agent review and discusses the review methods and results. The phase one review identified a short list of agent systems that would prove most useful in the service architecture of an information management, analysis, and retrieval system. Reviewers evaluated open-source and commercial multi-agent systems and scored them based upon viability, uniqueness, ease of development, ease of deployment, and ease of integration with other products. Based on these criteria, reviewers identified the ten most appropriate systems. The report also mentions several systems that reviewers deemed noteworthy for the ideas they implement, even if those systems are not the best choices for information management purposes.

  14. Marine-derived anticancer agents in clinical trials.

    PubMed

    Schwartsmann, Gilberto; Da Rocha, Adriana Brondani; Mattei, Jane; Lopes, RafaelMartins

    2003-08-01

    Anticancer agents may be derived either from the isolation of an active lead compound occurring spontaneously in nature or by novel chemical synthesis in the laboratory. There are examples of successful drugs being derived from both sources, which have had a profound impact on the natural history of various types of cancer. The treatment of lymphomas and acute leukaemias with the use of combination chemotherapy, including anthracyclines and vinca alkaloids, are examples of the contribution of nature. In contrast, agents such as 5-fluorouracil, methotrexate and more recently, the humanised anti-CD20 antibody rituximab and the tyrosine kinase inhibitor imatinib are examples of synthetic compounds, which were designed with a clear rationale, that are routinely used in patients with solid tumours and haematological malignancies. Until recently, the tradition in natural product-derived anticancer drug development was to rely almost exclusively on the screening of terrestrial sources (plant extracts and fermentation products) for their cytotoxic properties. Although C-nucleosides obtained from Caribbean sponge were the initial inspiration for the synthesis of antiviral substituted nucleosides and the successful anticancer agent citarabine, active against leukaemias and lymphomas, the contribution of marine compounds as a source of anticancer agents was modest. In recent years, the improvements in the technology of deep-sea collection and aquaculture added to the growing recognition of the tremendous biodiversity present in the marine world, and has contributed to the growing interest of exploring the oceans as a potential source of new anticancer candidates. This is reflected in the number of marine-derived compounds undergoing preclinical and early clinical development. In this paper, the authors discuss the available literature on anticancer agents that have reached clinical trials, such as didemnin B, aplidine, dolastatin-10, bryostatin-1 and ecteinascidin-743 (ET-743

  15. Leveraging synergy for multiple agent infotaxis

    SciTech Connect

    Gintautas, Vadas; Hagberg, Aric A; Bettencourt, Luis M A

    2008-01-01

    Social computation, whether in the form of a search performed by a swarm of agents or the predictions of markets, often supplies remarkably good solutions to complex problems, which often elude the best experts. There is an intuition, built upon many anecdotal examples, that pervading principles are at play that allow individuals trying to solve a problem locally to aggregate their information to arrive at an outcome superior than any available to isolated parties. Here we show that the general structure of this problem can be cast in terms of information theory and derive general mathematical conditions for information sharing and coordination that lead to optimal multi-agent searches. Specifically we illustrate the problem in terms of the construction of local search algorithms for autonomous agents looking for the spatial location of a stochastic source. We explore the types of search problems -defined in terms of the properties of the source and the nature of measurements at each sensor -for which coordination among multiple searchers yields an advantage beyond that gained by having the same number of independent searchers. We assert that effective coordination corresponds to synergy and that ineffective coordination corresponds to redundancy as defined using information theory. We classify explicit types of sources in terms of their potential for synergy. We show that sources that emit uncorrelated particles based on a Poisson process, provide no opportunity for synergetic coordination while others, particularly sources that emit correlated signals, do allow for strong synergy between searchers. These general considerations are crucial for designing optimal algorithms for particular search problems in real world settings.

  16. Therapeutic potential of chalcones as cardiovascular agents.

    PubMed

    Mahapatra, Debarshi Kar; Bharti, Sanjay Kumar

    2016-03-01

    Cardiovascular diseases are the leading cause of death affecting 17.3 million people across the globe and are estimated to affect 23.3 million people by year 2030. In recent years, about 7.3 million people died due to coronary heart disease, 9.4 million deaths due to high blood pressure and 6.2 million due to stroke, where obesity and atherosclerotic progression remain the chief pathological factors. The search for newer and better cardiovascular agents is the foremost need to manage cardiac patient population across the world. Several natural and (semi) synthetic chalcones deserve the credit of being potential candidates to inhibit various cardiovascular, hematological and anti-obesity targets like angiotensin converting enzyme (ACE), cholesteryl ester transfer protein (CETP), diacylglycerol acyltransferase (DGAT), acyl-coenzyme A: cholesterol acyltransferase (ACAT), pancreatic lipase (PL), lipoprotein lipase (LPL), calcium (Ca(2+))/potassium (K(+)) channel, COX-1, TXA2 and TXB2. In this review, a comprehensive study of chalcones, their therapeutic targets, structure activity relationships (SARs), mechanisms of actions (MOAs) have been discussed. Chemically diverse chalcone scaffolds, their derivatives including structural manipulation of both aryl rings, replacement with heteroaryl scaffold(s) and hybridization through conjugation with other pharmacologically active scaffold have been highlighted. Chalcones which showed promising activity and have a well-defined MOAs, SARs must be considered as prototype for the design and development of potential anti-hypertensive, anti-anginal, anti-arrhythmic and cardioprotective agents. With the knowledge of these molecular targets, structural insights and SARs, this review may be helpful for (medicinal) chemists to design more potent, safe, selective and cost effective chalcone derivatives as potential cardiovascular agents. PMID:26876916

  17. Thyroid Dysfunction from Antineoplastic Agents

    PubMed Central

    Larsen, P. Reed; Marqusee, Ellen

    2011-01-01

    Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%–50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient’s quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182

  18. Thyroid dysfunction from antineoplastic agents.

    PubMed

    Hamnvik, Ole-Petter Riksfjord; Larsen, P Reed; Marqusee, Ellen

    2011-11-01

    Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%-50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient's quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182

  19. Evaluating Water Demand Using Agent-Based Modeling

    NASA Astrophysics Data System (ADS)

    Lowry, T. S.

    2004-12-01

    The supply and demand of water resources are functions of complex, inter-related systems including hydrology, climate, demographics, economics, and policy. To assess the safety and sustainability of water resources, planners often rely on complex numerical models that relate some or all of these systems using mathematical abstractions. The accuracy of these models relies on how well the abstractions capture the true nature of the systems interactions. Typically, these abstractions are based on analyses of observations and/or experiments that account only for the statistical mean behavior of each system. This limits the approach in two important ways: 1) It cannot capture cross-system disruptive events, such as major drought, significant policy change, or terrorist attack, and 2) it cannot resolve sub-system level responses. To overcome these limitations, we are developing an agent-based water resources model that includes the systems of hydrology, climate, demographics, economics, and policy, to examine water demand during normal and extraordinary conditions. Agent-based modeling (ABM) develops functional relationships between systems by modeling the interaction between individuals (agents), who behave according to a probabilistic set of rules. ABM is a "bottom-up" modeling approach in that it defines macro-system behavior by modeling the micro-behavior of individual agents. While each agent's behavior is often simple and predictable, the aggregate behavior of all agents in each system can be complex, unpredictable, and different than behaviors observed in mean-behavior models. Furthermore, the ABM approach creates a virtual laboratory where the effects of policy changes and/or extraordinary events can be simulated. Our model, which is based on the demographics and hydrology of the Middle Rio Grande Basin in the state of New Mexico, includes agent groups of residential, agricultural, and industrial users. Each agent within each group determines its water usage

  20. Autonomous sensor manager agents (ASMA)

    NASA Astrophysics Data System (ADS)

    Osadciw, Lisa A.

    2004-04-01

    Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

  1. Nature Detectives

    ERIC Educational Resources Information Center

    Harr, Natalie; Lee, Richard E.; Jr.

    2010-01-01

    Richard Louv's "Last Child in the Woods" (2008) added to a growing consensus to get children outside and experiencing nature. Using ideas from place-based education, the authors present a simple year-long project that brings science, nature, and other curriculum standards to life right in your school yard. With a focus on journaling, this project…

  2. Nature plants.

    PubMed

    2014-06-01

    We welcome our new sister journal Nature Plants and the increased commitment to the plant science community that it represents. This is an opportunity for Nature Genetics to emphasize the use of genetic and genomic tools and resources in discovering new plant biology and solving major agricultural challenges.

  3. Matematica Natural.

    ERIC Educational Resources Information Center

    Lozano, Patricia; Medearis, Linda

    Matematica Natural (Natural Mathematics) is a mathematics curriculum for young children based on the assumption that they learn mathematics through concrete, real life, relevant experiences and that educational differences rather than cultural differences influence math achievement. The curriculum uses hands-on materials and activities to teach…

  4. Natural Beauty

    ERIC Educational Resources Information Center

    Coy, Mary

    2006-01-01

    In this article, the author describes how her art class students were able to create, in just four class periods, clay relief plaques depicting nature. A lesson on texture speeds up the completion of such a project. Seeing that clay is a natural material with its own unique texture, it seemed fitting that the final product should depict a variety…

  5. Antimicrobial peptides: Possible anti-infective agents.

    PubMed

    Lakshmaiah Narayana, Jayaram; Chen, Jyh-Yih

    2015-10-01

    Multidrug-resistant bacterial, fungal, viral, and parasitic infections are major health threats. The Infectious Diseases Society of America has expressed concern on the decrease of pharmaceutical companies working on antibiotic research and development. However, small companies, along with academic research institutes, are stepping forward to develop novel therapeutic methods to overcome the present healthcare situation. Among the leading alternatives to current drugs are antimicrobial peptides (AMPs), which are abundantly distributed in nature. AMPs exhibit broad-spectrum activity against a wide variety of bacteria, fungi, viruses, and parasites, and even cancerous cells. They also show potential immunomodulatory properties, and are highly responsive to infectious agents and innate immuno-stimulatory molecules. In recent years, many AMPs have undergone or are undergoing clinical development, and a few are commercially available for topical and other applications. In this review, we outline selected anion and cationic AMPs which are at various stages of development, from preliminary analysis to clinical drug development. Moreover, we also consider current production methods and delivery tools for AMPs, which must be improved for the effective use of these agents.

  6. Quorum Quenching Agents: Resources for Antivirulence Therapy

    PubMed Central

    Tang, Kaihao; Zhang, Xiao-Hua

    2014-01-01

    The continuing emergence of antibiotic-resistant pathogens is a concern to human health and highlights the urgent need for the development of alternative therapeutic strategies. Quorum sensing (QS) regulates virulence in many bacterial pathogens, and thus, is a promising target for antivirulence therapy which may inhibit virulence instead of cell growth and division. This means that there is little selective pressure for the evolution of resistance. Many natural quorum quenching (QQ) agents have been identified. Moreover, it has been shown that many microorganisms are capable of producing small molecular QS inhibitors and/or macromolecular QQ enzymes, which could be regarded as a strategy for bacteria to gain benefits in competitive environments. More than 30 species of marine QQ bacteria have been identified thus far, but only a few of them have been intensively studied. Recent studies indicate that an enormous number of QQ microorganisms are undiscovered in the highly diverse marine environments, and these marine microorganism-derived QQ agents may be valuable resources for antivirulence therapy. PMID:24886865

  7. Ecdysteroids: A novel class of anabolic agents?

    PubMed

    Parr, M K; Botrè, F; Naß, A; Hengevoss, J; Diel, P; Wolber, G

    2015-06-01

    Increasing numbers of dietary supplements with ecdysteroids are marketed as "natural anabolic agents". Results of recent studies suggested that their anabolic effect is mediated by estrogen receptor (ER) binding. Within this study the anabolic potency of ecdysterone was compared to well characterized anabolic substances. Effects on the fiber sizes of the soleus muscle in rats as well the diameter of C2C12 derived myotubes were used as biological readouts. Ecdysterone exhibited a strong hypertrophic effect on the fiber size of rat soleus muscle that was found even stronger compared to the test compounds metandienone (dianabol), estradienedione (trenbolox), and SARM S 1, all administered in the same dose (5 mg/kg body weight, for 21 days). In C2C12 myotubes ecdysterone (1 µM) induced a significant increase of the diameter comparable to dihydrotestosterone (1 µM) and IGF 1 (1.3 nM). Molecular docking experiments supported the ERβ mediated action of ecdysterone. To clarify its status in sports, ecdysterone should be considered to be included in the class "S1.2 Other Anabolic Agents" of the list of prohibited substances of the World Anti-Doping Agency. PMID:26060342

  8. Rodents as potential couriers for bioterrorism agents.

    PubMed

    Lõhmus, Mare; Janse, Ingmar; van de Goot, Frank; van Rotterdam, Bart J

    2013-09-01

    Many pathogens that can cause major public health, economic, and social damage are relatively easily accessible and could be used as biological weapons. Wildlife is a natural reservoir for many potential bioterrorism agents, and, as history has shown, eliminating a pathogen that has dispersed among wild fauna can be extremely challenging. Since a number of wild rodent species live close to humans, rodents constitute a vector for pathogens to circulate among wildlife, domestic animals, and humans. This article reviews the possible consequences of a deliberate spread of rodentborne pathogens. It is relatively easy to infect wild rodents with certain pathogens or to release infected rodents, and the action would be difficult to trace. Rodents can also function as reservoirs for diseases that have been spread during a bioterrorism attack and cause recurring disease outbreaks. As rats and mice are common in both urban and rural settlements, deliberately released rodentborne infections have the capacity to spread very rapidly. The majority of pathogens that are listed as potential agents of bioterrorism by the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases exploit rodents as vectors or reservoirs. In addition to zoonotic diseases, deliberately released rodentborne epizootics can have serious economic consequences for society, for example, in the area of international trade restrictions. The ability to rapidly detect introduced diseases and effectively communicate with the public in crisis situations enables a quick response and is essential for successful and cost-effective disease control.

  9. Probiotics as Antiviral Agents in Shrimp Aquaculture

    PubMed Central

    Lakshmi, Bestha; Sai Gopal, D. V. R.

    2013-01-01

    Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases. PMID:23738078

  10. Quorum quenching agents: resources for antivirulence therapy.

    PubMed

    Tang, Kaihao; Zhang, Xiao-Hua

    2014-06-01

    The continuing emergence of antibiotic-resistant pathogens is a concern to human health and highlights the urgent need for the development of alternative therapeutic strategies. Quorum sensing (QS) regulates virulence in many bacterial pathogens, and thus, is a promising target for antivirulence therapy which may inhibit virulence instead of cell growth and division. This means that there is little selective pressure for the evolution of resistance. Many natural quorum quenching (QQ) agents have been identified. Moreover, it has been shown that many microorganisms are capable of producing small molecular QS inhibitors and/or macromolecular QQ enzymes, which could be regarded as a strategy for bacteria to gain benefits in competitive environments. More than 30 species of marine QQ bacteria have been identified thus far, but only a few of them have been intensively studied. Recent studies indicate that an enormous number of QQ microorganisms are undiscovered in the highly diverse marine environments, and these marine microorganism-derived QQ agents may be valuable resources for antivirulence therapy.

  11. Successful technical trading agents using genetic programming.

    SciTech Connect

    Othling, Andrew S.; Kelly, John A.; Pryor, Richard J.; Farnsworth, Grant V.

    2004-10-01

    Genetic programming (GP) has proved to be a highly versatile and useful tool for identifying relationships in data for which a more precise theoretical construct is unavailable. In this project, we use a GP search to develop trading strategies for agent based economic models. These strategies use stock prices and technical indicators, such as the moving average convergence/divergence and various exponentially weighted moving averages, to generate buy and sell signals. We analyze the effect of complexity constraints on the strategies as well as the relative performance of various indicators. We also present innovations in the classical genetic programming algorithm that appear to improve convergence for this problem. Technical strategies developed by our GP algorithm can be used to control the behavior of agents in economic simulation packages, such as ASPEN-D, adding variety to the current market fundamentals approach. The exploitation of arbitrage opportunities by technical analysts may help increase the efficiency of the simulated stock market, as it does in the real world. By improving the behavior of simulated stock markets, we can better estimate the effects of shocks to the economy due to terrorism or natural disasters.

  12. Rodents as potential couriers for bioterrorism agents.

    PubMed

    Lõhmus, Mare; Janse, Ingmar; van de Goot, Frank; van Rotterdam, Bart J

    2013-09-01

    Many pathogens that can cause major public health, economic, and social damage are relatively easily accessible and could be used as biological weapons. Wildlife is a natural reservoir for many potential bioterrorism agents, and, as history has shown, eliminating a pathogen that has dispersed among wild fauna can be extremely challenging. Since a number of wild rodent species live close to humans, rodents constitute a vector for pathogens to circulate among wildlife, domestic animals, and humans. This article reviews the possible consequences of a deliberate spread of rodentborne pathogens. It is relatively easy to infect wild rodents with certain pathogens or to release infected rodents, and the action would be difficult to trace. Rodents can also function as reservoirs for diseases that have been spread during a bioterrorism attack and cause recurring disease outbreaks. As rats and mice are common in both urban and rural settlements, deliberately released rodentborne infections have the capacity to spread very rapidly. The majority of pathogens that are listed as potential agents of bioterrorism by the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases exploit rodents as vectors or reservoirs. In addition to zoonotic diseases, deliberately released rodentborne epizootics can have serious economic consequences for society, for example, in the area of international trade restrictions. The ability to rapidly detect introduced diseases and effectively communicate with the public in crisis situations enables a quick response and is essential for successful and cost-effective disease control. PMID:23971813

  13. Ecdysteroids: A novel class of anabolic agents?

    PubMed

    Parr, M K; Botrè, F; Naß, A; Hengevoss, J; Diel, P; Wolber, G

    2015-06-01

    Increasing numbers of dietary supplements with ecdysteroids are marketed as "natural anabolic agents". Results of recent studies suggested that their anabolic effect is mediated by estrogen receptor (ER) binding. Within this study the anabolic potency of ecdysterone was compared to well characterized anabolic substances. Effects on the fiber sizes of the soleus muscle in rats as well the diameter of C2C12 derived myotubes were used as biological readouts. Ecdysterone exhibited a strong hypertrophic effect on the fiber size of rat soleus muscle that was found even stronger compared to the test compounds metandienone (dianabol), estradienedione (trenbolox), and SARM S 1, all administered in the same dose (5 mg/kg body weight, for 21 days). In C2C12 myotubes ecdysterone (1 µM) induced a significant increase of the diameter comparable to dihydrotestosterone (1 µM) and IGF 1 (1.3 nM). Molecular docking experiments supported the ERβ mediated action of ecdysterone. To clarify its status in sports, ecdysterone should be considered to be included in the class "S1.2 Other Anabolic Agents" of the list of prohibited substances of the World Anti-Doping Agency.

  14. Probiotics as antiviral agents in shrimp aquaculture.

    PubMed

    Lakshmi, Bestha; Viswanath, Buddolla; Sai Gopal, D V R

    2013-01-01

    Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases.

  15. Transportation dynamics on networks of mobile agents

    NASA Astrophysics Data System (ADS)

    Yang, Han-Xin; Wang, Wen-Xu; Xie, Yan-Bo; Lai, Ying-Cheng; Wang, Bing-Hong

    2011-01-01

    Most existing works on transportation dynamics focus on networks of a fixed structure, but networks whose nodes are mobile have become widespread, such as cell-phone networks. We introduce a model to explore the basic physics of transportation on mobile networks. Of particular interest is the dependence of the throughput on the speed of agent movement and the communication range. Our computations reveal a hierarchical dependence for the former, while an algebraic power law is found between the throughput and the communication range with the exponent determined by the speed. We develop a physical theory based on the Fokker-Planck equation to explain these phenomena. Our findings provide insights into complex transportation dynamics arising commonly in natural and engineering systems.

  16. Biopolymeric agents for skin wrinkle treatment.

    PubMed

    Lourith, Nattaya; Kanlayavattanakul, Mayuree

    2016-10-01

    Skin aging is caused by several factors capable of deteriorating dermal matrix and is visibly noticed in skin color and skin contour deformities. In addition to the prevention of skin aging by application of antioxidants and sunscreens, treatment of skin wrinkles with those of dermal fillers is also recommended. Dermal filler products with enhanced injectability and longer duration are being developed continuously. Biodegradable polymers such as skin elastic fibers and dermal matrix mimetic used for treatment of skin wrinkle are summarized in this article. Additionally, the importance of amino acids, enzymes, and proteins in aesthetic of skin is addressed. Thus, elective agents are proposed for the dermatologists, cosmetic formulators, and the individuals facing skin aging problems. The candidate natural peptides from marine sources are additionally presented for widening the choice of actives application for treating aging. PMID:26963365

  17. Engineering knottins as novel binding agents.

    PubMed

    Moore, Sarah J; Cochran, Jennifer R

    2012-01-01

    Cystine-knot miniproteins, also known as knottins, contain a conserved core of three tightly woven disulfide bonds which impart extraordinary thermal and proteolytic stability. Interspersed between their conserved cysteine residues are constrained loops that possess high levels of sequence diversity among knottin family members. Together these attributes make knottins promising molecular scaffolds for protein engineering and translational applications. While naturally occurring knottins have shown potential as both diagnostic agents and therapeutics, protein engineering is playing an important and increasing role in creating designer molecules that bind to a myriad of biomedical targets. Toward this goal, rational and combinatorial approaches have been used to engineer knottins with novel molecular recognition properties. Here, methods are described for creating and screening knottin libraries using yeast surface display and fluorescence-activated cell sorting. Protocols are also provided for producing knottins by synthetic and recombinant methods, and for measuring the binding affinity of knottins to target proteins expressed on the cell surface.

  18. Exposure to toxic environmental agents.

    PubMed

    2013-10-01

    Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course.Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations,which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure.

  19. Exposure to toxic environmental agents.

    PubMed

    2013-10-01

    : Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course. Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations, which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure.

  20. Triggered pore-forming agents

    DOEpatents

    Bayley, H.; Walker, B.J.; Chang, C.Y.; Niblack, B.; Panchal, R.

    1998-07-07

    An inactive pore-forming agent is revealed which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell. 30 figs.

  1. 7 CFR 4290.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financial Assistance for RBICs (Leverage) Funding Leverage by Use of Guaranteed Trust Certificates (âtcsâ) § 4290.1620 Functions of agents... to: (i) Establish performance criteria for Poolers. (ii) Monitor and evaluate the financial...

  2. Direct Vasodilators and Sympatholytic Agents.

    PubMed

    McComb, Meghan N; Chao, James Y; Ng, Tien M H

    2016-01-01

    Direct vasodilators and sympatholytic agents were some of the first antihypertensive medications discovered and utilized in the past century. However, side effect profiles and the advent of newer antihypertensive drug classes have reduced the use of these agents in recent decades. Outcome data and large randomized trials supporting the efficacy of these medications are limited; however, in general the blood pressure-lowering effect of these agents has repeatedly been shown to be comparable to other more contemporary drug classes. Nevertheless, a landmark hypertension trial found a negative outcome with a doxazosin-based regimen compared to a chlorthalidone-based regimen, leading to the removal of α-1 adrenergic receptor blockers as first-line monotherapy from the hypertension guidelines. In contemporary practice, direct vasodilators and sympatholytic agents, particularly hydralazine and clonidine, are often utilized in refractory hypertension. Hydralazine and minoxidil may also be useful alternatives for patients with renal dysfunction, and both hydralazine and methyldopa are considered first line for the treatment of hypertension in pregnancy. Hydralazine has also found widespread use for the treatment of systolic heart failure in combination with isosorbide dinitrate (ISDN). The data to support use of this combination in African Americans with heart failure are particularly robust. Hydralazine with ISDN may also serve as an alternative for patients with an intolerance to angiotensin antagonists. Given these niche indications, vasodilators and sympatholytics are still useful in clinical practice; therefore, it is prudent to understand the existing data regarding efficacy and the safe use of these medications. PMID:26033778

  3. Nucleotide cleaving agents and method

    DOEpatents

    Que, Jr., Lawrence; Hanson, Richard S.; Schnaith, Leah M. T.

    2000-01-01

    The present invention provides a unique series of nucleotide cleaving agents and a method for cleaving a nucleotide sequence, whether single-stranded or double-stranded DNA or RNA, using and a cationic metal complex having at least one polydentate ligand to cleave the nucleotide sequence phosphate backbone to yield a hydroxyl end and a phosphate end.

  4. 7 CFR 4290.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Functions of agents, including Central Registration..., DEPARTMENT OF AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financial Assistance for RBICs (Leverage) Funding Leverage by Use of Guaranteed Trust Certificates (âtcsâ) § 4290.1620 Functions of...

  5. SEM: A Cultural Change Agent

    ERIC Educational Resources Information Center

    Barnes, Bradley; Bourke, Brian

    2015-01-01

    The authors advance the concept that institutional culture is a purposeful framework by which to view SEM's utility, particularly as a cultural change agent. Through the connection of seemingly independent functions of performance and behavior, implications emerge that deepen the understanding of the influence of culture on performance outcomes…

  6. [Effects of Intensity of Acting Agents on the Manifestation of Synergistic Interaction].

    PubMed

    Petin, V G; Zhurakovskaya, G P

    2015-01-01

    The universal dependence of the synergistic interaction on the intensity of the acting agents was demonstrated. This dependence is not associated with the biological object, as well as the nature of the physical or chemical agents used in the combined exposures. In all cases, with a decrease in the intensity of one of the agents the intensity of the other factor should be also decreased to ensure the greatest synergistic effect. Such relationship of synergy and the intensity of the acting agents is of interest for radiation safety. This regularity indicates the principal possibility of synergistic interaction of harmful environmental factors actually occurring in the biosphere at their low intensities. PMID:26964345

  7. Limonene and tetrahydrofurfuryl alcohol cleaning agent

    DOEpatents

    Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

    1996-05-07

    The present invention is a tetrahydrofurfuryl alcohol and limonene or terpineol cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  8. Limonene and tetrahydrofurfuryl alcohol cleaning agent

    DOEpatents

    Bohnert, G.W.; Carter, R.D.; Hand, T.E.; Powers, M.T.

    1997-10-21

    The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  9. Limonene and tetrahydrofurfurly alcohol cleaning agent

    DOEpatents

    Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

    1997-10-21

    The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  10. Halide test agent replacement study

    SciTech Connect

    Banks, E.M.; Freeman, W.P.; Kovach, B.J.

    1995-02-01

    The intended phaseout of the chlorofluorocarbons (CFCs) from commercial use required the evaluation of substitute materials for the testing for leak paths through both individual adsorbers and installed adsorbent banks. The American Society of Mechanical Engineers (ASME) Committee on Nuclear Air and Gas Treatment (CONAGT) is in charge of maintaining the standards and codes specifying adsorbent leak test methods for the nuclear safety related air cleaning systems. The currently published standards and codes cite the use of R-11, R-12 and R-112 for leak path test agents. All of these compounds are CFCs. There are other agencies and organizations (USDOE, USDOD and USNRC) also specifying testing for leak paths or in some cases for special life tests using the above compounds. The CONAGT has recently developed criteria for the suitability evaluation of substitute test agents. On the basis of these criteria, several compounds were evaluated for their acceptability as adsorbent bed leak and life test agents. The ASME CONAGT Test Agent Qualification Criteria. The test agent qualification is based on the following parameters: (1) Similar retention times on activated carbons at the same concentration levels as one of the following: R-11, R-12, R-112 or R-112a. (2) Similar lower detection limit sensitivity and precision in the concentration range of use as R-11, R-12, R-112 and R-112a. (3) Gives the same in-place leak test results as R-11, R-12, R-112, or R-112a. (4) Chemical and radiological stability under the use conditions. (5) Causes no degradation of the carbon and its impregnant or of the other NATS components under the use conditions. (6) Is listed in the USEPA Toxic Substances Control Act (TSCA) inventory for commercial use.

  11. Specific sequestering agents for iron and the actinides

    SciTech Connect

    Raymond, K.N.

    1983-06-01

    The transuranium actinide ions represent one unique environmental hazard associated with the waste of the nuclear power industry. A major component associated with that waste and a potential hazard is plutonium. The synthesis of metal-ion-specific complexing agents for ions such as Pu(IV) potentially represents a powerful new approach to many of the problems posed by waste treatment. This document is a progress report of a rational approach to the synthesis of such chelating agents based on the similarities of Pu(IV) and Fe(III), the structures of naturally-occurring complexing agents which are highly specific for Fe(III), and the incorporation of the same kinds of ligating groups present in the iron complexes to make octadentate complexes highly specific for plutonium. Both thermodynamic and animal test results indicate that a relatively high degree of success has already been achieved in this aim.

  12. Massively parallel sequencing, a new method for detecting adventitious agents.

    PubMed

    Onions, David; Kolman, John

    2010-05-01

    There has been an upsurge of interest in developing new veterinary and human vaccines and, in turn, this has involved the development of new mammalian and insect cell substrates. Excluding adventitious agents from these cells can be problematic, particularly for cells derived from species with limited virological investigation. Massively parallel sequencing is a powerful new method for the identification of viruses and other adventitious agents, without prior knowledge of the nature of the agent. We have developed methods using random priming to detect viruses in the supernatants from cell substrates or in virus seed stocks. Using these methods we have recently discovered a new parvovirus in bovine serum. When applied to sequencing the transcriptome, massively parallel sequencing can reveal latent or silent infections. Enormous amounts of data are developed in this process usually between 100 and 400 Mbp. Consequently, sophisticated bioinformatic algorithms are required to analyse and verify virus targets.

  13. Sequestering agents for the removal of actinides from waste streams

    SciTech Connect

    Raymond, K.N.; White, D.J.; Xu, Jide; Mohs, T.R.

    1997-10-01

    The goal of this project is to take a biomimetic approach toward developing new separation technologies for the removal of radioactive elements from contaminated DOE sites. To achieve this objective, the authors are investigating the fundamental chemistry of naturally occurring, highly specific metal ion sequestering agents and developing them into liquid/liquid and solid supported actinide extraction agents. Nature produces sideophores (e.g., Enterobactin and Desferrioxamine B) to selectivity sequester Lewis acidic metal ions, in particular Fe(III), from its surroundings. These chelating agents typically use multiple catechols or hydroxamic acids to form polydentate ligands that chelate the metal ion forming very stable complexes. The authors are investigating and developing analogous molecules into selective chelators targeting actinide(IV) ions, which display similar properties to Fe(III). By taking advantage of differences in charge, preferred coordination number, and pH stability range, the transition from nature to actinide sequestering agents has been applied to the development of new and highly selective actinide extraction technologies. Additionally, the authors have shown that these chelating ligands are versatile ligands for chelating U(VI). In particular, they have been studying their coordination chemistry and fundamental interactions with the uranyl ion [UO{sub 2}]{sup 2+}, the dominant form of uranium found in aqueous media. With an understanding of this chemistry, and results obtained from in vivo uranium sequestration studies, it should be possible to apply these actinide(IV) extraction technologies to the development of new extraction agents for the removal of uranium from waste streams.

  14. Natural Products from Mangrove Actinomycetes

    PubMed Central

    Xu, Dong-Bo; Ye, Wan-Wan; Han, Ying; Deng, Zi-Xin; Hong, Kui

    2014-01-01

    Mangroves are woody plants located in tropical and subtropical intertidal coastal regions. The mangrove ecosystem is becoming a hot spot for natural product discovery and bioactivity survey. Diverse mangrove actinomycetes as promising and productive sources are worth being explored and uncovered. At the time of writing, we report 73 novel compounds and 49 known compounds isolated from mangrove actinomycetes including alkaloids, benzene derivatives, cyclopentenone derivatives, dilactones, macrolides, 2-pyranones and sesquiterpenes. Attractive structures such as salinosporamides, xiamycins and novel indolocarbazoles are highlighted. Many exciting compounds have been proven as potential new antibiotics, antitumor and antiviral agents, anti-fibrotic agents and antioxidants. Furthermore, some of their biosynthetic pathways have also been revealed. This review is an attempt to consolidate and summarize the past and the latest studies on mangrove actinomycetes natural product discovery and to draw attention to their immense potential as novel and bioactive compounds for marine drugs discovery. PMID:24798926

  15. Does an Agent Matter? The Effects of Animated Pedagogical Agents on Multimedia Environments.

    ERIC Educational Resources Information Center

    Craig, Scotty D.; Gholson, Barry

    Data are presented on the effects of Animated Agents on multimedia learning environments with specific concerns of split attention and modality effects. The study was a 3 (agent properties: agent only, agent with gestures, no agent) x 3 (picture features: static picture, sudden onset, animation) factorial design with outcome measures of mental…

  16. The New Agent: A Qualitative Study to Strategically Adapt New Agent Professional Development

    ERIC Educational Resources Information Center

    Baker, Lauri M.; Hadley, Gregg

    2014-01-01

    The qualitative study reported here assessed the needs of agents related to new agent professional development to improve the current model. Agents who participated in new agent professional development within the last 5 years were selected to participate in focus groups to determine concerns and continued needs. Agents enjoyed networking and…

  17. Dietary Agents in Cancer Prevention: An Immunological Perspective †

    PubMed Central

    Zheng, Ya Ying; Viswanathan, Bharathi; Kesarwani, Pravin; Mehrotra, Shikhar

    2013-01-01

    Skin cancer is the most common form of cancer diagnosed in the United States. Exposure to solar ultraviolet (UV) radiations is believed to be the primary cause for skin cancer. Excessive UV radiation can lead to genetic mutations and damage in the skin's cellular DNA that in turn can lead to skin cancer. Lately, chemoprevention by administering naturally occurring non-toxic dietary compounds has proven to be a potential strategy to prevent the occurrence of tumors. Attention has been drawn towards several natural dietary agents such as resveratrol, one of the major components found in grapes, red wines, berries and peanuts, proanthocyanidins from grape seeds, (-)-epigallocatechin-3-gallate (EGCG) from green tea etc. However, the effect these dietary agents have on the immune system and the immunological mechanisms involved there in are still being explored. In this review we shall focus on the role of key chemopreventive agents on various immune cells and discuss their potential as anti-tumor agents with an immunological perspective. PMID:22372381

  18. Neuroprotective "agents" in surgery. Secret "agent" man, or common "agent" machine?

    NASA Technical Reports Server (NTRS)

    Andrews, R. J.

    1999-01-01

    The search for clinically-effective neuroprotective agents has received enormous support in recent years--an estimated $200 million by pharmaceutical companies on clinical trials for traumatic brain injury alone. At the same time, the pathophysiology of brain injury has proved increasingly complex, rendering the likelihood of a single agent "magic bullet" even more remote. On the other hand, great progress continues with technology that makes surgery less invasive and less risky. One example is the application of endovascular techniques to treat coronary artery stenosis, where both the invasiveness of sternotomy and the significant neurological complication rate (due to microemboli showering the cerebral vasculature) can be eliminated. In this paper we review aspects of intraoperative neuroprotection both present and future. Explanations for the slow progress on pharmacologic neuroprotection during surgery are presented. Examples of technical advances that have had great impact on neuroprotection during surgery are given both from coronary artery stenosis surgery and from surgery for Parkinson's disease. To date, the progress in neuroprotection resulting from such technical advances is an order of magnitude greater than that resulting from pharmacologic agents used during surgery. The progress over the last 20 years in guidance during surgery (CT and MRI image-guidance) and in surgical access (endoscopic and endovascular techniques) will soon be complemented by advances in our ability to evaluate biological tissue intraoperatively in real-time. As an example of such technology, the NASA Smart Probe project is considered. In the long run (i.e., in 10 years or more), pharmacologic "agents" aimed at the complex pathophysiology of nervous system injury in man will be the key to true intraoperative neuroprotection. In the near term, however, it is more likely that mundane "agents" based on computers, microsensors, and microeffectors will be the major impetus to improved

  19. Development of Class IIa Bacteriocins as Therapeutic Agents

    PubMed Central

    Lohans, Christopher T.; Vederas, John C.

    2012-01-01

    Class IIa bacteriocins have been primarily explored as natural food preservatives, but there is much interest in exploring the application of these peptides as therapeutic antimicrobial agents. Bacteriocins of this class possess antimicrobial activity against several important human pathogens. Therefore, the therapeutic development of these bacteriocins will be reviewed. Biological and chemical modifications to both stabilize and increase the potency of bacteriocins are discussed, as well as the optimization of their production and purification. The suitability of bacteriocins as pharmaceuticals is explored through determinations of cytotoxicity, effects on the natural microbiota, and in vivo efficacy in mouse models. Recent results suggest that class IIa bacteriocins show promise as a class of therapeutic agents. PMID:22187559

  20. CATS-based Agents That Err

    NASA Technical Reports Server (NTRS)

    Callantine, Todd J.

    2002-01-01

    This report describes preliminary research on intelligent agents that make errors. Such agents are crucial to the development of novel agent-based techniques for assessing system safety. The agents extend an agent architecture derived from the Crew Activity Tracking System that has been used as the basis for air traffic controller agents. The report first reviews several error taxonomies. Next, it presents an overview of the air traffic controller agents, then details several mechanisms for causing the agents to err in realistic ways. The report presents a performance assessment of the error-generating agents, and identifies directions for further research. The research was supported by the System-Wide Accident Prevention element of the FAA/NASA Aviation Safety Program.

  1. Advances in the discovery of novel antibacterial agents during the year 2002.

    PubMed

    Harris, Christina R; Thorarensen, Atli

    2004-08-01

    The development of bacterial resistance is a significant problem in the treatment of infection, and the importance of research directed toward the discovery of novel agents to treat infections cannot be underestimated. In the past, discovery programs have focused on modification of natural products or existing classes of marketed antibacterial agents. A significant period of time lapsed between the introduction of the nalidixic acid-based quinolones and the next novel antibacterial agent (Zyvox). However, the advent of the "genomics era" has provided a wealth of new targets that afford the opportunity to discover novel antibacterial agents. This review reports on the state of antibacterial research directed toward the development of novel antibacterial agents with novel mechanisms of action for the calendar year, 2002. While variations on existing drug classes continue to appear, we have chosen to limit our discussion to novel classes of antibacterial agents which have not yet been marketed.

  2. Biomorphic Multi-Agent Architecture for Persistent Computing

    NASA Technical Reports Server (NTRS)

    Lodding, Kenneth N.; Brewster, Paul

    2009-01-01

    A multi-agent software/hardware architecture, inspired by the multicellular nature of living organisms, has been proposed as the basis of design of a robust, reliable, persistent computing system. Just as a multicellular organism can adapt to changing environmental conditions and can survive despite the failure of individual cells, a multi-agent computing system, as envisioned, could adapt to changing hardware, software, and environmental conditions. In particular, the computing system could continue to function (perhaps at a reduced but still reasonable level of performance) if one or more component( s) of the system were to fail. One of the defining characteristics of a multicellular organism is unity of purpose. In biology, the purpose is survival of the organism. The purpose of the proposed multi-agent architecture is to provide a persistent computing environment in harsh conditions in which repair is difficult or impossible. A multi-agent, organism-like computing system would be a single entity built from agents or cells. Each agent or cell would be a discrete hardware processing unit that would include a data processor with local memory, an internal clock, and a suite of communication equipment capable of both local line-of-sight communications and global broadcast communications. Some cells, denoted specialist cells, could contain such additional hardware as sensors and emitters. Each cell would be independent in the sense that there would be no global clock, no global (shared) memory, no pre-assigned cell identifiers, no pre-defined network topology, and no centralized brain or control structure. Like each cell in a living organism, each agent or cell of the computing system would contain a full description of the system encoded as genes, but in this case, the genes would be components of a software genome.

  3. Pro-oxidant activity of dietary chemopreventive agents: an under-appreciated anti-cancer property.

    PubMed

    Azmi, Asfar S; Sarkar, Fazlul H; Hadi, S M

    2013-01-01

    " Let food be thy medicine and medicine be thy food" was quoted by Hippocrates more than two thousand years ago and since ancient times the health benefits of different natural agents have been exploited. In modern research, the disease preventive benefits of many such natural agents, particularly dietary compounds and their derivatives, has been attributed to their well recognized activity as the regulators of redox state of the cell. Nevertheless, most of these studies have focused on their antioxidant activity. A large body of evidence indicates that a major fraction of these agents can elicit pro-oxidant (radical generating) behavior which has been linked to their anti-cancer effects. This editorial provides an overview of the under-appreciated pro-oxidant activity of natural products, with a special focus on their ability to generate reactive oxygen species in the presence of transition metal ions, and discusses their possible use as cancer chemotherapeutic agents. PMID:24358870

  4. Infectious disease agents mediate interaction in food webs and ecosystems.

    PubMed

    Selakovic, Sanja; de Ruiter, Peter C; Heesterbeek, Hans

    2014-02-22

    Infectious agents are part of food webs and ecosystems via the relationship with their host species that, in turn, interact with both hosts and non-hosts. Through these interactions, infectious agents influence food webs in terms of structure, functioning and stability. The present literature shows a broad range of impacts of infectious agents on food webs, and by cataloguing that range, we worked towards defining the various mechanisms and their specific effects. To explore the impact, a direct approach is to study changes in food-web properties with infectious agents as separate species in the web, acting as additional nodes, with links to their host species. An indirect approach concentrates not on adding new nodes and links, but on the ways that infectious agents affect the existing links across host and non-host nodes, by influencing the 'quality' of consumer-resource interaction as it depends on the epidemiological state host involved. Both approaches are natural from an ecological point of view, but the indirect approach may connect more straightforwardly to commonly used tools in infectious disease dynamics.

  5. Infectious disease agents mediate interaction in food webs and ecosystems

    PubMed Central

    Selakovic, Sanja; de Ruiter, Peter C.; Heesterbeek, Hans

    2014-01-01

    Infectious agents are part of food webs and ecosystems via the relationship with their host species that, in turn, interact with both hosts and non-hosts. Through these interactions, infectious agents influence food webs in terms of structure, functioning and stability. The present literature shows a broad range of impacts of infectious agents on food webs, and by cataloguing that range, we worked towards defining the various mechanisms and their specific effects. To explore the impact, a direct approach is to study changes in food-web properties with infectious agents as separate species in the web, acting as additional nodes, with links to their host species. An indirect approach concentrates not on adding new nodes and links, but on the ways that infectious agents affect the existing links across host and non-host nodes, by influencing the ‘quality’ of consumer–resource interaction as it depends on the epidemiological state host involved. Both approaches are natural from an ecological point of view, but the indirect approach may connect more straightforwardly to commonly used tools in infectious disease dynamics. PMID:24403336

  6. Plants' Metabolites as Potential Antiobesity Agents

    PubMed Central

    Gooda Sahib, Najla; Saari, Nazamid; Ismail, Amin; Khatib, Alfi; Mahomoodally, Fawzi; Abdul Hamid, Azizah

    2012-01-01

    Obesity and obesity-related complications are on the increase both in the developed and developing world. Since existing pharmaceuticals fail to come up with long-term solutions to address this issue, there is an ever-pressing need to find and develop new drugs and alternatives. Natural products, particularly medicinal plants, are believed to harbor potential antiobesity agents that can act through various mechanisms either by preventing weight gain or promoting weight loss amongst others. The inhibition of key lipid and carbohydrate hydrolyzing and metabolizing enzymes, disruption of adipogenesis, and modulation of its factors or appetite suppression are some of the plethora of targeted approaches to probe the antiobesity potential of medicinal plants. A new technology such as metabolomics, which deals with the study of the whole metabolome, has been identified to be a promising technique to probe the progression of diseases, elucidate their pathologies, and assess the effects of natural health products on certain pathological conditions. This has been applied to drug research, bone health, and to a limited extent to obesity research. This paper thus endeavors to give an overview of those plants, which have been reported to have antiobesity effects and highlight the potential and relevance of metabolomics in obesity research. PMID:22666121

  7. 2,5-diketopiperazines as neuroprotective agents.

    PubMed

    Cornacchia, C; Cacciatore, I; Baldassarre, L; Mollica, A; Feliciani, F; Pinnen, F

    2012-01-01

    2,5-diketopiperazines are the simplest cyclic peptides found in nature, commonly biosynthesized from amino acids by different organisms, and represent a promising class of biologically active natural products. Their peculiar heterocyclic structure confers high stability against the proteolysis and constitutes a structural requirement for the active intestinal absorption. Furthermore, the diketopiperazine-based motif is considered as a novel brain shuttle for the delivery of drugs with limited ability to cross the blood-brain barrier (BBB) and can be proposed as an ideal candidate for the rational development of new therapeutic agents. Although these cyclic peptides have been known since the beginning of the 20th century, only recently have they attracted substantial interest with respect to the wide spectrum of their biological properties, including antitumor, antiviral, antifungal, antibacterial and antihyperglycemic activities. In addition to these, the most challenging function of the diketopiperazine derivatives is related with their remarkable neuroprotective and nootropic activity. The aim of the present paper is to provide an overview of the two major classes of diketopiperazines, the TRH-related and the unsaturated derivatives both characterized by a significant ability to protect against neurotoxicity in several experimental models. The neuroprotective profile of these compounds suggests that they may have a future utility in the therapy of neuronal degeneration in vivo, potentially through several different mechanisms.

  8. Chaotic neurodynamics for autonomous agents.

    PubMed

    Harter, Derek; Kozma, Robert

    2005-05-01

    Mesoscopic level neurodynamics study the collective dynamical behavior of neural populations. Such models are becoming increasingly important in understanding large-scale brain processes. Brains exhibit aperiodic oscillations with a much more rich dynamical behavior than fixed-point and limit-cycle approximation allow. Here we present a discretized model inspired by Freeman's K-set mesoscopic level population model. We show that this version is capable of replicating the important principles of aperiodic/chaotic neurodynamics while being fast enough for use in real-time autonomous agent applications. This simplification of the K model provides many advantages not only in terms of efficiency but in simplicity and its ability to be analyzed in terms of its dynamical properties. We study the discrete version using a multilayer, highly recurrent model of the neural architecture of perceptual brain areas. We use this architecture to develop example action selection mechanisms in an autonomous agent. PMID:15940987

  9. Novel Antiangiogenic Agents in Dermatology

    PubMed Central

    Berrios, Ricardo L.; Arbiser, Jack L.

    2011-01-01

    Because angiogenesis underlies the pathogenesis of numerous conditions (cancer, psoriasis, macular degeneration), there is a pressing need for continued investigations into angiogenic signaling and potential drug targets. Antiangiogenic agents can be classified as either direct or indirect. Direct antiangiogenics act on untransformed endothelial cells to prevent differentiation and proliferation; indirect antiangiogenics act to inhibit factors involved in proangiogenic signaling. Agents currently available with dermatologic indications are few, while several established and novel biologics targeting various proangiogenic factors are currently being investigated for potential dermatologic uses, but the jury is still out on their efficacy and safety. In this review, we highlight our experience with a group of existing and novel, small molecules that combine several modes of action against angiogenesis in addition to other properties – triarylmethane dyes and fulvene derivatives. PMID:21172300

  10. Bacteriocins as Potential Anticancer Agents

    PubMed Central

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity toward cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies. PMID:26617524

  11. Bacteriocins as Potential Anticancer Agents.

    PubMed

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity toward cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies.

  12. [Pharmacology of bone anabolic agents].

    PubMed

    Matsumoto, Toshio

    2015-10-01

    Bone is constantly remodeled to maintain its volume, structural integrity and strength Currently available bone anabolic agent is teriparatide. Teriparatide increases bone mass and strength via both remodeling-dependent and -independent mechanisms, although remodeling-dependent mechanism overweighs the other. Canonical Wnt signal plays an important role in enhancing osteoblast differentiation and bone formation, and its osteocyte-derived inhibitor, sclerostin, regulates bone formation via the regulation of Wnt signaling. Anti-sclerostin antibody stimulates Wnt signaling and enhances bone formation. Phase II clinical trials with anti-sclerostin antibodies, romosozumab and blosozumab, demonstrated a marked increase in bone mineral density after one year of treatment. The new modality of anabolic agents via remodeling-independent stimulation of bone formation may open up a new avenue for the treatment of osteoporosis.

  13. Oral agents in multiple sclerosis.

    PubMed

    Lorefice, L; Fenu, G; Frau, J; Coghe, G C; Marrosu, M G; Cocco, E

    2015-01-01

    Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system. Disease-modifying drugs licensed for MS treatment have been developed to reduce relapse rates and halt disease progression. The majority of current MS drugs involve regular, parenteral administration, affecting long-term adherence and thus reducing treatment efficacy. Over the last two decades great progress has been made towards developing new MS therapies with different modes of action and biologic effects. In particular, oral drugs have generated much interest because of their convenience and positive impact on medication adherence. Fingolimod was the first launched oral treatment for relapsing-remitting MS; recently, Teriflunomide and Dimethyl fumarate have also been approved as oral disease-modifying agents. In this review, we summarize and discuss the history, pharmacodynamics, efficacy, and safety of oral agents that have been approved or are under development for the selective treatment of MS. PMID:25924620

  14. Hyperlipidemia sink for anesthetic agents.

    PubMed

    Johnson, Thomas J; Porhomayon, Jahan; Nader, Nader D; Eldesouki, Enas; Smith, Kelly; Hobika, Geoffrey G

    2016-11-01

    We present a case that involves anesthetic resistance during anesthesia for electroconvulsive therapy. Despite adequate dosing of both intravenous and inhalation anesthetics, our patient was resistant to induction of the state of general anesthesia. Subsequently, we noticed extreme hyperlipidemia. We hypothesized that the patient's extreme hyperlipidemia served as an anesthetic "sink" and prevented the full dose of intravenous agents from quickly reaching their intended site of action.

  15. Implementation and evaluation of an virtual intelligent agent.

    PubMed

    Moore, Mary; Ahmed, Terry

    2003-01-01

    Reference librarians at the National Library of Medicine answer over 100,000 client questions annually. Although many answers are the NLM Web, clients may have difficulty finding them. Using intelligent virtual agent software, the NLM launched Cosmo, the Customer Service Owl (http://wwwns.nlm.nih.gov/). Cosmo uses natural language pattern matching to answer common questions. Early evaluation shows Cosmo can answer 25% of questions asked, but some users mistake the service for chat reference or a search engine.

  16. Pharmacologic Agents for Chronic Diarrhea.

    PubMed

    Lee, Kwang Jae

    2015-10-01

    Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly. PMID:26576135

  17. Mortality among agricultural extension agents.

    PubMed

    Alavanja, M C; Blair, A; Merkle, S; Teske, J; Eaton, B

    1988-01-01

    The mortality experience of agricultural extension agents in the Cooperative Extension Service (CES) of the U.S. Department of Agriculture who died during the period January 1, 1970-December 31, 1979 (n = 1,495 white males) was evaluated in proportionate-mortality and case-control studies. The proportionate-mortality analysis was used to identify cancers that might be elevated in this occupational group compared with the U.S. white male population. All cancers with a significantly elevated proportionate-mortality ratio were more thoroughly evaluated in the case-control study, where there is presumably less of a selection bias in the comparison. In the case-control study, leukemia demonstrated a statistically significant linear trend with duration of employment as an extension agent. Smaller, but nonsignificant, trends were seen for non-Hodgkin's lymphoma, multiple myeloma, and brain cancer. The odds ratio for Hodgkin's disease and cancers of the colon, prostate, and kidney did not vary with the number of years on the job. These patterns resemble cancer risks seen among farmers, suggesting that agricultural factors may also play a role in the origin of these tumors among extension agents.

  18. Pharmacologic Agents for Chronic Diarrhea

    PubMed Central

    2015-01-01

    Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly. PMID:26576135

  19. Pharmacologic Agents for Chronic Diarrhea.

    PubMed

    Lee, Kwang Jae

    2015-10-01

    Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly.

  20. Multi-agent autonomous system

    NASA Technical Reports Server (NTRS)

    Fink, Wolfgang (Inventor); Dohm, James (Inventor); Tarbell, Mark A. (Inventor)

    2010-01-01

    A multi-agent autonomous system for exploration of hazardous or inaccessible locations. The multi-agent autonomous system includes simple surface-based agents or craft controlled by an airborne tracking and command system. The airborne tracking and command system includes an instrument suite used to image an operational area and any craft deployed within the operational area. The image data is used to identify the craft, targets for exploration, and obstacles in the operational area. The tracking and command system determines paths for the surface-based craft using the identified targets and obstacles and commands the craft using simple movement commands to move through the operational area to the targets while avoiding the obstacles. Each craft includes its own instrument suite to collect information about the operational area that is transmitted back to the tracking and command system. The tracking and command system may be further coupled to a satellite system to provide additional image information about the operational area and provide operational and location commands to the tracking and command system.

  1. Surface decontamination for blister agents Lewisite, sulfur mustard and agent yellow, a Lewisite and sulfur mustard mixture.

    PubMed

    Stone, Harry; See, David; Smiley, Autumn; Ellingson, Anthony; Schimmoeller, Jessica; Oudejans, Lukas

    2016-08-15

    Sulfur mustard (HD) and Lewisite (L) are blister agents that have a high potential for terrorist use; Agent Yellow (HL) is the eutectic mixture of HD and L. Bench-scale testing was used to determine the residual amount of these chemical warfare agents remaining on three building materials (wood, metal and glass) after application of various decontaminants (household bleach, full strength and dilute; hydrogen peroxide 3% solution; and EasyDECON(®) DF200). All decontaminants reduced the amount of L recovered from coupons. Application of dilute bleach showed little or no difference compared to natural attenuation in the amount of HD recovered from coupons. Full-strength bleach was the most effective of four decontaminants at reducing the amount of HD from coupons. Hydrogen peroxide (3% solution) and DF200 did decrease the amount of HD recovered from coupons more than natural attenuation (except DF200 against HD on metal), but substantial amounts of HD remained on some materials. Toxic HD by-products were generated by hydrogen peroxide treatment. The effectiveness of decontaminants was found to depend on agent, material, and decontaminant. Increased decontaminant reaction time (60min rather than 30min) did not significantly increase effectiveness. PMID:27107236

  2. Surface decontamination for blister agents Lewisite, sulfur mustard and agent yellow, a Lewisite and sulfur mustard mixture.

    PubMed

    Stone, Harry; See, David; Smiley, Autumn; Ellingson, Anthony; Schimmoeller, Jessica; Oudejans, Lukas

    2016-08-15

    Sulfur mustard (HD) and Lewisite (L) are blister agents that have a high potential for terrorist use; Agent Yellow (HL) is the eutectic mixture of HD and L. Bench-scale testing was used to determine the residual amount of these chemical warfare agents remaining on three building materials (wood, metal and glass) after application of various decontaminants (household bleach, full strength and dilute; hydrogen peroxide 3% solution; and EasyDECON(®) DF200). All decontaminants reduced the amount of L recovered from coupons. Application of dilute bleach showed little or no difference compared to natural attenuation in the amount of HD recovered from coupons. Full-strength bleach was the most effective of four decontaminants at reducing the amount of HD from coupons. Hydrogen peroxide (3% solution) and DF200 did decrease the amount of HD recovered from coupons more than natural attenuation (except DF200 against HD on metal), but substantial amounts of HD remained on some materials. Toxic HD by-products were generated by hydrogen peroxide treatment. The effectiveness of decontaminants was found to depend on agent, material, and decontaminant. Increased decontaminant reaction time (60min rather than 30min) did not significantly increase effectiveness.

  3. Agent planning in AgScala

    NASA Astrophysics Data System (ADS)

    Tošić, Saša; Mitrović, Dejan; Ivanović, Mirjana

    2013-10-01

    Agent-oriented programming languages are designed to simplify the development of software agents, especially those that exhibit complex, intelligent behavior. This paper presents recent improvements of AgScala, an agent-oriented programming language based on Scala. AgScala includes declarative constructs for managing beliefs, actions and goals of intelligent agents. Combined with object-oriented and functional programming paradigms offered by Scala, it aims to be an efficient framework for developing both purely reactive, and more complex, deliberate agents. Instead of the Prolog back-end used initially, the new version of AgScala relies on Agent Planning Package, a more advanced system for automated planning and reasoning.

  4. Investigation of Vietnamese plants for potential anticancer agents

    PubMed Central

    Pérez, Lynette Bueno; Still, Patrick C.; Naman, C. Benjamin; Ren, Yulin; Pan, Li; Chai, Hee-Byung; Carcache de Blanco, Esperanza J.; Ninh, Tran Ngoc; Van Thanh, Bui; Swanson, Steven M.; Soejarto, Djaja D.

    2014-01-01

    Higher plants continue to afford humankind with many new drugs, for a variety of disease types. In this review, recent phytochemical and biological progress is presented for part of a collaborative multi-institutional project directed towards the discovery of new antitumor agents. The specific focus is on bioactive natural products isolated and characterized structurally from tropical plants collected in Vietnam. The plant collection, identification, and processing steps are described, and the natural products isolated from these species are summarized with their biological activities. PMID:25395897

  5. [Natural selection].

    PubMed

    Mayr, E

    1985-05-01

    Much of the resistance against Darwin's theory of natural selection has been due to misunderstandings. It is shown that natural selection is not a tautology and that it is a two-step process. The first step, the production of variation, is under the control of chance; the second step, selection proper, is an anti-chance process, but subject to many constraints. The target of selection is the individual as a whole, and many neutral mutations can be retained as hitchhikers of successful genotypes. Sexual selection results from selection for pure reproductive success.

  6. Uranium, natural

    Integrated Risk Information System (IRIS)

    Uranium , natural ; CASRN 7440 - 61 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  7. Nature Watch

    ERIC Educational Resources Information Center

    Sterling, Donna R.

    2010-01-01

    Children are naturally curious about the world in which they live. To focus this sense of wonder, have your students investigate their local habitat as it changes over the year. This multiseason study will build connections and add relevance to the habitats that children learn about. This series of activities for grades 4-6 explores the changing…

  8. Nature's Palette

    ERIC Educational Resources Information Center

    McBride, Brooke B.; Brewer, Carol A.

    2010-01-01

    Flower petals, acorn hats, exoskeletons of beetles, and lichens are just a few of the objects students may find in a surprising array of vivid colors. These tiny examples from nature's palette can be discovered in a school yard, a park, or even along the edges of a paved sidewalk...it simply takes careful observation! This article describes a…

  9. Natural restoration

    SciTech Connect

    Kamlet, K.S.

    1993-02-01

    After a company pays millions of dollars to clean up contaminated site, its liability may not be over. It may have to spend tens of millions more to restore damaged natural resources under an oft-overlooked Superfund program. Examples of liability are cited in this report from the Exxon Valdez oil spill and a pcb leak which contaminated a harbor.

  10. Natural ecosystems

    USGS Publications Warehouse

    Fleishman, Erica; Belnap, Jayne; Cobb, Neil; Enquist, Carolyn A.F.; Ford, Karl; MacDonald, Glen; Pellant, Mike; Schoennagel, Tania; Schmit, Lara M.; Schwartz, Mark; van Drunick, Suzanne; Westerling, Anthony LeRoy; Keyser, Alisa; Lucas, Ryan

    2013-01-01

    Natural Ecosystems analyzes the association of observed changes in climate with changes in the geographic distributions and phenology (the timing of blossoms or migrations of birds) for Southwestern ecosystems and their species, portraying ecosystem disturbances—such as wildfires and outbreaks of forest pathogens—and carbon storage and release, in relation to climate change.

  11. Radiation crosslinked thermoplastics natural rubber (TPNR) foams

    NASA Astrophysics Data System (ADS)

    Ghazali, Z.; Johnson, A. F.; Dahlan, K. Z.

    1999-06-01

    Thermoplastic natural rubber is gaining wider interest and like other thermoplastic elastomers, offers the processibility of thermoplastic as well as functional performances and properties of conventional thermoset rubbers. This paper describes an evaluation made of the suitability of foaming blends of natural rubber and EVA using chemical blowing agents. Crosslinking was achieved by exposing the TPNR to electron beam irradiation (EB) at 20, 30, 40, 60, 80, 100, 120, 150 and 200 kGy doses. The relationships between foam density and concentration of blowing agent as well as foaming parameters such as time and temperature were evaluated.

  12. Chemopreventive Agent Development | Division of Cancer Prevention

    Cancer.gov

    This group promotes and supports research on early chemopreventive agent development, from preclinical studies to pha | Research on early chemopreventive agent development, from preclinical studies to phase I clinical trials.

  13. Intelligent Agents as Cognitive Tools for Education.

    ERIC Educational Resources Information Center

    Baylor, Amy

    1999-01-01

    Examines the educational potential for intelligent agents as cognitive tools. Discusses the role of intelligent agents: managing large amounts of information (information overload), serving as a pedagogical expert, and creating programming environments for the learner. (AEF)

  14. 7 CFR 58.720 - Acidifying agents.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.720 Acidifying agents. Acidifying agents if used shall be those permitted by the Food...

  15. 7 CFR 58.628 - Sweetening agents.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.628 Sweetening agents. Sweetening agents shall be clean and wholesome and consist of one...

  16. Learning other agents` preferences in multiagent negotiation

    SciTech Connect

    Bui, H.H.; Kieronska, D.; Venkatesh, S.

    1996-12-31

    In multiagent systems, an agent does not usually have complete information about the preferences and decision making processes of other agents. This might prevent the agents from making coordinated choices, purely due to their ignorance of what others want. This paper describes the integration of a learning module into a communication-intensive negotiating agent architecture. The learning module gives the agents the ability to learn about other agents` preferences via past interactions. Over time, the agents can incrementally update their models of other agents` preferences and use them to make better coordinated decisions. Combining both communication and learning, as two complement knowledge acquisition methods, helps to reduce the amount of communication needed on average, and is justified in situations where communication is computationally costly or simply not desirable (e.g. to preserve the individual privacy).

  17. Extinguishing agent for combustible metal fires

    DOEpatents

    Riley, John F.; Stauffer, Edgar Eugene

    1976-10-12

    A low chloride extinguishing agent for combustible metal fires comprising from substantially 75 to substantially 94 weight percent of sodium carbonate as the basic fire extinguishing material, from substantially 1 to substantially 5 weight percent of a water-repellent agent such as a metal stearate, from substantially 2 to substantially 10 weight percent of a flow promoting agent such as attapulgus clay, and from substantially 3 to substantially 15 weight percent of a polyamide resin as a crusting agent.

  18. Conformity-driven agents support ordered phases in the spatial public goods game

    NASA Astrophysics Data System (ADS)

    Javarone, Marco Alberto; Antonioni, Alberto; Caravelli, Francesco

    2016-05-01

    We investigate the spatial Public Goods Game in the presence of fitness-driven and conformity-driven agents. This framework usually considers only the former type of agents, i.e., agents that tend to imitate the strategy of their fittest neighbors. However, whenever we study social systems, the evolution of a population might be affected also by social behaviors as conformism, stubbornness, altruism, and selfishness. Although the term evolution can assume different meanings depending on the considered domain, here it corresponds to the set of processes that lead a system towards an equilibrium or a steady state. We map fitness to the agents' payoff so that richer agents are those most imitated by fitness-driven agents, while conformity-driven agents tend to imitate the strategy assumed by the majority of their neighbors. Numerical simulations aim to identify the nature of the transition, on varying the amount of the relative density of conformity-driven agents in the population, and to study the nature of related equilibria. Remarkably, we find that conformism generally fosters ordered cooperative phases and may also lead to bistable behaviors.

  19. Pathogenic agents in freshwater resources

    NASA Astrophysics Data System (ADS)

    Geldreich, Edwin E.

    1996-02-01

    Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation. These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters. Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored. The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen.As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary. In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology.Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters. Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters and stormwater runoff. All of these contributions are intensified during periods of major floods. Several water-borne case histories are cited as examples of breakdowns in public health protection related to water supply, recreational waters and the consumption of contaminated salad crops. In the long term, water resource management must focus on pollution prevention from point sources of waste discharges and the spread of pathogens in watershed stormwater runoff.

  20. Agent 2003 Conference on Challenges in Social Simulation

    SciTech Connect

    Margaret Clemmons, ed.

    2003-01-01

    Welcome to the Proceedings of the fourth in a series of agent simulation conferences cosponsored by Argonne National Laboratory and The University of Chicago. Agent 2003 is the second conference in which three Special Interest Groups from the North American Association for Computational Social and Organizational Science (NAACSOS) have been involved in planning the program--Computational Social Theory; Simulation Applications; and Methods, Toolkits and Techniques. The theme of Agent 2003, Challenges in Social Simulation, is especially relevant, as there seems to be no shortage of such challenges. Agent simulation has been applied with increasing frequency to social domains for several decades, and its promise is clear and increasingly visible. Like any nascent scientific methodology, however, it faces a number of problems or issues that must be addressed in order to progress. These challenges include: (1) Validating models relative to the social settings they are designed to represent; (2) Developing agents and interactions simple enough to understand but sufficiently complex to do justice to the social processes of interest; (3) Bridging the gap between empirically spare artificial societies and naturally occurring social phenomena; (4) Building multi-level models that span processes across domains; (5) Promoting a dialog among theoretical, qualitative, and empirical social scientists and area experts, on the one hand, and mathematical and computational modelers and engineers, on the other; (6) Using that dialog to facilitate substantive progress in the social sciences; and (7) Fulfilling the aspirations of users in business, government, and other application areas, while recognizing and addressing the preceding challenges. Although this list hardly exhausts the challenges the field faces, it does identify topics addressed throughout the presentations of Agent 2003. Agent 2003 is part of a much larger process in which new methods and techniques are applied to

  1. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  2. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  3. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  4. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  5. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  6. Hydroxypyridonate chelating agents and synthesis thereof

    DOEpatents

    Raymond, K.N.; Scarrow, R.C.; White, D.L.

    1985-11-12

    Chelating agents having 1-hydroxy-2-pyridinone (HOPO) and related moieties incorporated within their structures, including polydentate HOPO-substituted polyamines such as spermidine and spermine, and HOPO-substituted desferrioxamine. The chelating agents are useful in selectively removing certain cations from solution, and are particularly useful as ferric ion and actinide chelators. Novel syntheses of the chelating agents are provided. 4 tabs.

  7. 24 CFR 232.1011 - Management agents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Management agents. 232.1011 Section... Management agents. (a) An operator or borrower may, with the prior written approval of HUD, execute a management agent agreement setting forth the duties and procedures for matters related to the management...

  8. 24 CFR 232.1011 - Management agents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Management agents. 232.1011 Section... Management agents. (a) An operator or borrower may, with the prior written approval of HUD, execute a management agent agreement setting forth the duties and procedures for matters related to the management...

  9. Construction and Evaluation of Animated Teachable Agents

    ERIC Educational Resources Information Center

    Bodenheimer, Bobby; Williams, Betsy; Kramer, Mattie Ruth; Viswanath, Karun; Balachandran, Ramya; Belynne, Kadira; Biswas, Gautam

    2009-01-01

    This article describes the design decisions, technical approach, and evaluation of the animation and interface components for an agent-based system that allows learners to learn by teaching. Students learn by teaching an animated agent using a visual representation. The agent can answer questions about what she has been taught and take quizzes.…

  10. Online Deception Detection Using BDI Agents

    ERIC Educational Resources Information Center

    Merritts, Richard A.

    2013-01-01

    This research has two facets within separate research areas. The research area of Belief, Desire and Intention (BDI) agent capability development was extended. Deception detection research has been advanced with the development of automation using BDI agents. BDI agents performed tasks automatically and autonomously. This study used these…

  11. Using Intelligent Agents To Assist Educators.

    ERIC Educational Resources Information Center

    Knode, Steve; Knode, Jon-David W.

    This paper begins with background on intelligent agents (software programs built to perform certain specific tasks for the user). A taxonomy that categorizes intelligent agents by the degree of intelligence embedded in the software is presented. Applications of today's intelligent agents are discussed, including specific examples of the following:…

  12. Infants Attribute to Agents Goals and Dispositions

    ERIC Educational Resources Information Center

    Luo, Yuyan; Choi, You-jung

    2012-01-01

    This commentary article is to be published alongside: Hernik, M., & Southgate, V. (2012). What do infants know about agents' goals? The authors see this issue consisting of two closely related questions. First, what is an agent to infants? Second, how do infants attribute goals to agents? Hernik and Southgage (H&S) focused on the second question.…

  13. 7 CFR 1430.210 - MILC agents.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... MILC agents. (a) MILC benefits may be disbursed by a dairy marketing cooperative that serves special... operation may authorize an agent of a dairy cooperative or milk handler affiliated with such cooperative to... 7 Agriculture 10 2010-01-01 2010-01-01 false MILC agents. 1430.210 Section 1430.210...

  14. 46 CFR Sec. 2 - General Agent's requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false General Agent's requirements. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY SLOP CHESTS Sec. 2 General Agent's requirements. The General Agent shall: (a) Obtain from the Master, a requisition for...

  15. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND... AGREEMENT Sec. 2 General Agents' authority. The General Agents are: (a) Hereby delegated authority...

  16. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents'...

  17. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND... AGREEMENT Sec. 2 General Agents' authority. The General Agents are: (a) Hereby delegated authority...

  18. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents'...

  19. 46 CFR Sec. 2 - General Agent's requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false General Agent's requirements. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY SLOP CHESTS Sec. 2 General Agent's requirements. The General Agent shall: (a) Obtain from the Master, a requisition for...

  20. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND... AGREEMENT Sec. 2 General Agents' authority. The General Agents are: (a) Hereby delegated authority...